chore: update libghostty vendor

refs #276

17 files changed, 5405 insertions, 74 deletions

diff --git a/vendor/libghostty-vt/src/terminal/PageList.zig b/vendor/libghostty-vt/src/terminal/PageList.zig
index 17eea73d..8e5cd193 100644
--- a/vendor/libghostty-vt/src/terminal/PageList.zig
+++ b/vendor/libghostty-vt/src/terminal/PageList.zig
@@ -658,6 +658,11 @@ pub fn deinit(self: *PageList) void {
 pub fn reset(self: *PageList) void {
     defer self.assertIntegrity();
 
+    // Invalidate all external page refs to the previous list. The reset below
+    // rebuilds the page list from the pools, so old untracked refs must be
+    // rejected before any validation attempts to inspect their node pointers.
+    self.page_serial_min = self.page_serial;
+
     // We need enough pages/nodes to keep our active area. This should
     // never fail since we by definition have allocated a page already
     // that fits our size but I'm not confident to make that assertion.
@@ -935,6 +940,10 @@ pub const Resize = struct {
     pub const Cursor = struct {
         x: size.CellCountInt,
         y: size.CellCountInt,
+
+        /// When set, this pin preserves right-side blank cells up to the cursor
+        /// during reflow.
+        pin: ?*Pin = null,
     };
 };
 
@@ -1013,10 +1022,6 @@ fn resizeCols(
 ) Allocator.Error!void {
     assert(cols != self.cols);
 
-    // Update our cols. We have to do this early because grow() that we
-    // may call below relies on this to calculate the proper page size.
-    self.cols = cols;
-
     // If we have a cursor position (x,y), then we try under any col resizing
     // to keep the same number remaining active rows beneath it. This is a
     // very special case if you can imagine clearing the screen (i.e.
@@ -1025,10 +1030,11 @@ fn resizeCols(
     // pull down scrollback.
     const preserved_cursor: ?struct {
         tracked_pin: *Pin,
+        untrack: bool,
         remaining_rows: usize,
         wrapped_rows: usize,
     } = if (cursor) |c| cursor: {
-        const p = self.pin(.{ .active = .{
+        const p = if (c.pin) |cursor_pin| cursor_pin.* else self.pin(.{ .active = .{
             .x = c.x,
             .y = c.y,
         } }) orelse break :cursor null;
@@ -1051,12 +1057,21 @@ fn resizeCols(
         };
 
         break :cursor .{
-            .tracked_pin = try self.trackPin(p),
+            .tracked_pin = c.pin orelse try self.trackPin(p),
+            .untrack = c.pin == null,
             .remaining_rows = self.rows - c.y - 1,
             .wrapped_rows = wrapped,
         };
     } else null;
-    defer if (preserved_cursor) |c| self.untrackPin(c.tracked_pin);
+    defer if (preserved_cursor) |c| {
+        if (c.untrack) self.untrackPin(c.tracked_pin);
+    };
+
+    // Update our cols. We have to do this early because grow() that we
+    // may call below relies on this to calculate the proper page size, but
+    // after preserved_cursor so that the cursor pin can resolve coordinates in
+    // the old active coordinate space.
+    self.cols = cols;
 
     // Create the first node that contains our reflow.
     const first_rewritten_node = node: {
@@ -1110,7 +1125,11 @@ fn resizeCols(
     {
         var reflow_cursor: ReflowCursor = .init(first_rewritten_node);
         while (it.next()) |row| {
-            try reflow_cursor.reflowRow(self, row);
+            try reflow_cursor.reflowRow(
+                self,
+                row,
+                if (preserved_cursor) |c| c.tracked_pin else null,
+            );
 
             // Once we're done reflowing a page, destroy it immediately.
             // This frees memory and makes it more likely in memory
@@ -1226,6 +1245,7 @@ const ReflowCursor = struct {
         self: *ReflowCursor,
         list: *PageList,
         row: Pin,
+        cursor_pin: ?*Pin,
     ) Allocator.Error!void {
         const src_page: *Page = &row.node.data;
         const src_row = row.rowAndCell().row;
@@ -1253,6 +1273,8 @@ const ReflowCursor = struct {
                 if (&p.node.data != src_page or
                     p.y != src_y) continue;
 
+                if (cursor_pin != null and p == cursor_pin.?) continue;
+
                 // If this pin is in the blanks on the right and past the end
                 // of the dst col width then we move it to the end of the dst
                 // col width instead.
@@ -1268,6 +1290,14 @@ const ReflowCursor = struct {
             }
         }
 
+        // If the cursor is after blanks on the right, those cells are still
+        // before the next write and must reflow with it.
+        if (cursor_pin) |p| {
+            if (&p.node.data == src_page and p.y == src_y) {
+                cols_len = @max(cols_len, p.x + 1);
+            }
+        }
+
         // Defer processing of blank rows so that blank rows
         // at the end of the page list are never written.
         if (cols_len == 0) {
@@ -13518,6 +13548,30 @@ test "PageList reset" {
     }, s.getTopLeft(.active));
 }
 
+test "PageList reset invalidates stale untracked refs even if node memory is reused" {
+    const testing = std.testing;
+    const alloc = testing.allocator;
+
+    var s = try init(alloc, 80, 24, null);
+    defer s.deinit();
+
+    const old_serial = s.pages.first.?.serial;
+    try testing.expect(old_serial >= s.page_serial_min);
+    try testing.expect(old_serial < s.page_serial);
+
+    s.reset();
+
+    // The important safety property is that stale serials are rejected before
+    // the node pointer is inspected. Reset rebuilds the page list from the
+    // pools, so old untracked refs may contain node pointers that are no
+    // longer safe to dereference.
+    try testing.expect(old_serial < s.page_serial_min);
+
+    const new_serial = s.pages.first.?.serial;
+    try testing.expect(new_serial >= s.page_serial_min);
+    try testing.expect(new_serial < s.page_serial);
+}
+
 test "PageList reset across two pages" {
     const testing = std.testing;
     const alloc = testing.allocator;
diff --git a/vendor/libghostty-vt/src/terminal/Screen.zig b/vendor/libghostty-vt/src/terminal/Screen.zig
index 39fdd610..becda78b 100644
--- a/vendor/libghostty-vt/src/terminal/Screen.zig
+++ b/vendor/libghostty-vt/src/terminal/Screen.zig
@@ -13,6 +13,7 @@ const tripwire = @import("../tripwire.zig");
 const unicode = @import("../unicode/main.zig");
 const Selection = @import("Selection.zig");
 const PageList = @import("PageList.zig");
+const selection_codepoints = @import("selection_codepoints.zig");
 const StringMap = @import("StringMap.zig");
 const ScreenFormatter = @import("formatter.zig").ScreenFormatter;
 const osc = @import("osc.zig");
@@ -1766,7 +1767,11 @@ pub inline fn resize(
         .rows = opts.rows,
         .cols = opts.cols,
         .reflow = opts.reflow,
-        .cursor = .{ .x = self.cursor.x, .y = self.cursor.y },
+        .cursor = .{
+            .x = self.cursor.x,
+            .y = self.cursor.y,
+            .pin = self.cursor.page_pin,
+        },
     });
 
     // If we have no scrollback and we shrunk our rows, we must explicitly
@@ -2512,7 +2517,7 @@ pub const SelectLine = struct {
 
     /// These are the codepoints to consider whitespace to trim
     /// from the ends of the selection.
-    whitespace: ?[]const u21 = &.{ 0, ' ', '\t' },
+    whitespace: ?[]const u21 = &selection_codepoints.default_line_whitespace,
 
     /// If true, line selection will consider semantic prompt
     /// state changing a boundary. State changing is ANY state
@@ -2648,10 +2653,10 @@ pub fn selectLine(self: *const Screen, opts: SelectLine) ?Selection {
             if (!cell.hasText()) continue;
 
             // Non-empty means we found it.
-            const this_whitespace = std.mem.indexOfAny(
+            const this_whitespace = std.mem.indexOfScalar(
                 u21,
                 whitespace,
-                &[_]u21{cell.content.codepoint},
+                cell.content.codepoint,
             ) != null;
             if (this_whitespace) continue;
 
@@ -2670,10 +2675,10 @@ pub fn selectLine(self: *const Screen, opts: SelectLine) ?Selection {
             if (!cell.hasText()) continue;
 
             // Non-empty means we found it.
-            const this_whitespace = std.mem.indexOfAny(
+            const this_whitespace = std.mem.indexOfScalar(
                 u21,
                 whitespace,
-                &[_]u21{cell.content.codepoint},
+                cell.content.codepoint,
             ) != null;
             if (this_whitespace) continue;
 
@@ -2794,10 +2799,10 @@ pub fn selectWord(
     if (!start_cell.hasText()) return null;
 
     // Determine if we are a boundary or not to determine what our boundary is.
-    const expect_boundary = std.mem.indexOfAny(
+    const expect_boundary = std.mem.indexOfScalar(
         u21,
         boundary_codepoints,
-        &[_]u21{start_cell.content.codepoint},
+        start_cell.content.codepoint,
     ) != null;
 
     // Go forwards to find our end boundary
@@ -2812,10 +2817,10 @@ pub fn selectWord(
             if (!cell.hasText()) break :end prev;
 
             // If we do not match our expected set, we hit a boundary
-            const this_boundary = std.mem.indexOfAny(
+            const this_boundary = std.mem.indexOfScalar(
                 u21,
                 boundary_codepoints,
-                &[_]u21{cell.content.codepoint},
+                cell.content.codepoint,
             ) != null;
             if (this_boundary != expect_boundary) break :end prev;
 
@@ -2849,10 +2854,10 @@ pub fn selectWord(
             if (!cell.hasText()) break :start prev;
 
             // If we do not match our expected set, we hit a boundary
-            const this_boundary = std.mem.indexOfAny(
+            const this_boundary = std.mem.indexOfScalar(
                 u21,
                 boundary_codepoints,
-                &[_]u21{cell.content.codepoint},
+                cell.content.codepoint,
             ) != null;
             if (this_boundary != expect_boundary) break :start prev;
 
@@ -7277,6 +7282,41 @@ test "Screen: resize less cols to eliminate wide char with row space" {
     }
 }
 
+test "Screen: resize less cols reflows cursor after wrapped text" {
+    const testing = std.testing;
+    const alloc = testing.allocator;
+    var s = try Screen.init(alloc, .{ .cols = 50, .rows = 7, .max_scrollback = 0 });
+    defer s.deinit();
+
+    for (0..30) |_| try s.testWriteString("a");
+
+    try testing.expectEqual(@as(usize, 0), s.cursor.y);
+    try testing.expectEqual(@as(usize, 30), s.cursor.x);
+
+    try s.resize(.{ .cols = 25, .rows = 7 });
+
+    try testing.expectEqual(@as(usize, 1), s.cursor.y);
+    try testing.expectEqual(@as(usize, 5), s.cursor.x);
+}
+
+test "Screen: resize less cols reflows cursor after empty cells" {
+    const testing = std.testing;
+    const alloc = testing.allocator;
+    var s = try Screen.init(alloc, .{ .cols = 10, .rows = 3, .max_scrollback = 0 });
+    defer s.deinit();
+
+    try s.testWriteString("abc");
+    s.cursorRight(6);
+
+    try testing.expectEqual(@as(usize, 0), s.cursor.y);
+    try testing.expectEqual(@as(usize, 9), s.cursor.x);
+
+    try s.resize(.{ .cols = 5, .rows = 3 });
+
+    try testing.expectEqual(@as(usize, 1), s.cursor.y);
+    try testing.expectEqual(@as(usize, 4), s.cursor.x);
+}
+
 test "Screen: resize more cols with wide spacer head" {
     const testing = std.testing;
     const alloc = testing.allocator;
diff --git a/vendor/libghostty-vt/src/terminal/ScreenSet.zig b/vendor/libghostty-vt/src/terminal/ScreenSet.zig
index d0856da5..4d3689e3 100644
--- a/vendor/libghostty-vt/src/terminal/ScreenSet.zig
+++ b/vendor/libghostty-vt/src/terminal/ScreenSet.zig
@@ -30,6 +30,11 @@ active: *Screen,
 /// All screens that are initialized.
 all: std.EnumMap(Key, *Screen),
 
+/// Monotonic generation counter for each screen key. This changes whenever a
+/// screen is removed so external handles can distinguish a newly initialized
+/// screen from stale references into destroyed screen storage.
+generations: std.EnumMap(Key, usize),
+
 pub fn init(
     alloc: Allocator,
     opts: Screen.Options,
@@ -42,6 +47,7 @@ pub fn init(
         .active_key = .primary,
         .active = screen,
         .all = .init(.{ .primary = screen }),
+        .generations = .initFull(0),
     };
 }
 
@@ -59,6 +65,11 @@ pub fn get(self: *const ScreenSet, key: Key) ?*Screen {
     return self.all.get(key);
 }
 
+/// Get the current generation for the given screen key.
+pub fn generation(self: *const ScreenSet, key: Key) usize {
+    return self.generations.get(key).?;
+}
+
 /// Get the screen for the given key, initializing it if necessary.
 pub fn getInit(
     self: *ScreenSet,
@@ -82,6 +93,7 @@ pub fn remove(
 ) void {
     assert(key != .primary);
     if (self.all.fetchRemove(key)) |screen| {
+        self.generations.put(key, self.generation(key) +% 1);
         screen.deinit();
         alloc.destroy(screen);
     }
@@ -99,9 +111,40 @@ test ScreenSet {
     var set: ScreenSet = try .init(alloc, .default);
     defer set.deinit(alloc);
     try testing.expectEqual(.primary, set.active_key);
+    try testing.expectEqual(@as(usize, 0), set.generation(.primary));
+    try testing.expectEqual(@as(usize, 0), set.generation(.alternate));
 
     // Initialize a secondary screen
     _ = try set.getInit(alloc, .alternate, .default);
+    try testing.expectEqual(@as(usize, 0), set.generation(.alternate));
+
     set.switchTo(.alternate);
     try testing.expectEqual(.alternate, set.active_key);
 }
+
+test "ScreenSet generations" {
+    const alloc = testing.allocator;
+    var set: ScreenSet = try .init(alloc, .default);
+    defer set.deinit(alloc);
+
+    try testing.expectEqual(@as(usize, 0), set.generation(.primary));
+    try testing.expectEqual(@as(usize, 0), set.generation(.alternate));
+
+    // A no-op removal doesn't change the generation.
+    set.remove(alloc, .alternate);
+    try testing.expectEqual(@as(usize, 0), set.generation(.alternate));
+
+    // Initializing a screen doesn't change the generation.
+    _ = try set.getInit(alloc, .alternate, .default);
+    try testing.expectEqual(@as(usize, 0), set.generation(.alternate));
+
+    const alternate_generation = set.generation(.alternate);
+    set.remove(alloc, .alternate);
+    try testing.expectEqual(alternate_generation +% 1, set.generation(.alternate));
+
+    // Reinitializing keeps the generation from the last removal, so stale
+    // handles can distinguish the new screen from the destroyed screen.
+    _ = try set.getInit(alloc, .alternate, .default);
+    try testing.expectEqual(alternate_generation +% 1, set.generation(.alternate));
+    try testing.expectEqual(@as(usize, 0), set.generation(.primary));
+}
diff --git a/vendor/libghostty-vt/src/terminal/Selection.zig b/vendor/libghostty-vt/src/terminal/Selection.zig
index 8cb52816..5258210c 100644
--- a/vendor/libghostty-vt/src/terminal/Selection.zig
+++ b/vendor/libghostty-vt/src/terminal/Selection.zig
@@ -4,6 +4,7 @@ const Selection = @This();
 const std = @import("std");
 const assert = @import("../quirks.zig").inlineAssert;
 const Allocator = std.mem.Allocator;
+const lib = @import("lib.zig");
 const page = @import("page.zig");
 const point = @import("point.zig");
 const PageList = @import("PageList.zig");
@@ -195,7 +196,12 @@ pub fn bottomRight(self: Selection, s: *const Screen) Pin {
 ///  operations only flip the x or y axis, not both. Depending on the y axis
 ///  direction, this is either mirrored_forward or mirrored_reverse.
 ///
-pub const Order = enum { forward, reverse, mirrored_forward, mirrored_reverse };
+pub const Order = lib.Enum(lib.target, &.{
+    "forward",
+    "reverse",
+    "mirrored_forward",
+    "mirrored_reverse",
+});
 
 pub fn order(self: Selection, s: *const Screen) Order {
     const start_pt = s.pages.pointFromPin(.screen, self.start()).?.screen;
@@ -389,18 +395,18 @@ pub fn containedRowCached(
 }
 
 /// Possible adjustments to the selection.
-pub const Adjustment = enum {
-    left,
-    right,
-    up,
-    down,
-    home,
-    end,
-    page_up,
-    page_down,
-    beginning_of_line,
-    end_of_line,
-};
+pub const Adjustment = lib.Enum(lib.target, &.{
+    "left",
+    "right",
+    "up",
+    "down",
+    "home",
+    "end",
+    "page_up",
+    "page_down",
+    "beginning_of_line",
+    "end_of_line",
+});
 
 /// Adjust the selection by some given adjustment. An adjustment allows
 /// a selection to be expanded slightly left, right, up, down, etc.
diff --git a/vendor/libghostty-vt/src/terminal/SelectionGesture.zig b/vendor/libghostty-vt/src/terminal/SelectionGesture.zig
new file mode 100644
index 00000000..f0e11f63
--- /dev/null
+++ b/vendor/libghostty-vt/src/terminal/SelectionGesture.zig
@@ -0,0 +1,2024 @@
+/// SelectionGesture manages gesture-based terminal text selection for one
+/// pointer stream: press, drag, release, autoscroll, and pressure/deep-press
+/// selection.
+///
+/// This type owns only the state required to interpret a gesture. It does not
+/// modify the terminal selection directly, except for scrolling the viewport
+/// during `autoscrollTick`. The caller feeds platform events into this type and
+/// applies the returned `Selection` to the active screen when appropriate.
+///
+/// A typical single-click drag flow looks like this:
+///
+/// ```zig
+/// const selection = try gesture.press(terminal, .{ ... });
+/// try terminal.screens.active.select(selection);
+/// if (gesture.drag(terminal, .{ ... })) |selection| {
+///     try terminal.screens.active.select(selection);
+/// }
+/// gesture.release(terminal, .{ ... });
+/// ```
+///
+/// Double- and triple-click gestures use the same event flow. Repeated presses
+/// inside `Press.repeat_interval` and within `Press.max_distance` increment the
+/// internal click count up to three. `Press.behaviors` maps single-, double-,
+/// and triple-clicks to behavior. By default, a single press returns null to
+/// clear any existing selection, a double-click returns a word selection, and a
+/// triple-click returns a line selection. Drags use the behavior selected by the
+/// corresponding press. A new press that is too late, too far away, or on
+/// another active screen starts a new single-click gesture.
+///
+/// # Resetting and lifetime
+///
+/// `release` ends the active drag/autoscroll phase but intentionally preserves
+/// enough state for a subsequent press to become a double- or triple-click.
+/// Call `reset` when the gesture is cancelled rather than released normally, or
+/// when another subsystem takes ownership of pointer input. Examples include
+/// enabling mouse reporting for an application, losing pointer/button state,
+/// destroying the surface, switching to a mode that must not continue text
+/// selection, or otherwise abandoning the current click sequence. Call `deinit`
+/// once before discarding the gesture object so any tracked click pin is
+/// released.
+///
+/// # Terminal and screen changes
+///
+/// The initial press pin is tracked in the active screen's `PageList`, so normal
+/// terminal output and viewport scrolling can move rows without making the
+/// gesture immediately stale. Selection results are computed against the current
+/// terminal contents at the time of each call. For example, a double-click drag
+/// selects word boundaries from the screen as it exists during `drag`, not from a
+/// snapshot captured at `press`.
+///
+/// The tracked pin is tied to both a `ScreenSet.Key` and that screen's
+/// generation. If the active screen changes, or a screen is removed/recycled,
+/// `validatedLeftClickPin` returns null and drag-style operations stop producing
+/// selections. `autoscrollTick` treats this as cancellation and calls `reset` so
+/// callers can stop their timers. This avoids exposing pins from inactive or
+/// freed screens, but it does not make a historical snapshot of terminal data.
+///
+/// # Concurrency
+///
+/// SelectionGesture is not concurrency safe. It has mutable gesture state and
+/// mutates/tracks pins inside the terminal page list without taking locks. The
+/// caller must serialize all calls that touch the same gesture and terminal,
+/// typically by holding the same terminal/renderer mutex used for other screen
+/// mutations. Do not call `press`, `drag`, `release`, `reset`, `deinit`, or
+/// `autoscrollTick` concurrently with each other or with unrelated terminal
+/// mutations unless the caller provides that synchronization.
+const SelectionGesture = @This();
+
+const std = @import("std");
+const builtin = @import("builtin");
+const assert = std.debug.assert;
+const testing = std.testing;
+const Allocator = std.mem.Allocator;
+const lib = @import("lib.zig");
+const PageList = @import("PageList.zig");
+const Pin = PageList.Pin;
+const Screen = @import("Screen.zig");
+const ScreenSet = @import("ScreenSet.zig");
+const Selection = @import("Selection.zig");
+const Terminal = @import("Terminal.zig");
+const point = @import("point.zig");
+
+const freestanding_wasm = builtin.target.cpu.arch == .wasm32 and
+    builtin.target.os.tag == .freestanding;
+
+/// Monotonic timestamp type for click-repeat detection.
+///
+/// Freestanding wasm cannot reference std.time.Instant because Zig's stdlib
+/// Instant type depends on POSIX timespec for that target, so represent the C
+/// API nanosecond timestamp directly as a u64 there.
+pub const Time = if (freestanding_wasm) u64 else std.time.Instant;
+
+/// The tracked pin of the initial left click along with the screen
+/// that the pin is part of.
+left_click_pin: ?*Pin,
+left_click_screen: ScreenSet.Key,
+left_click_screen_generation: usize,
+
+/// The count of clicks to count double and triple clicks and so on.
+/// The left click time was the last time the left click was done, if the
+/// caller could provide one. If this is null then we only support single clicks.
+left_click_count: u3,
+left_click_time: ?Time,
+
+/// The selection behavior chosen for the active left-click gesture.
+left_click_behavior: Behavior,
+
+/// The starting xpos/ypos of the left click. Note that if scrolling occurs,
+/// these will point to different cells, but the xpos/ypos will stay
+/// stable during scrolling relative to the surface.
+left_click_xpos: f64,
+left_click_ypos: f64,
+
+/// True once the active left-click gesture has moved away from the initially
+/// pressed cell. This is reset on every press that starts or continues a
+/// multi-click sequence, and is left available for callers to inspect while
+/// handling the corresponding release.
+left_click_dragged: bool,
+
+/// The current autoscroll state for the active left-click drag gesture.
+left_drag_autoscroll: Autoscroll,
+
+/// The direction that selection dragging should autoscroll the viewport.
+/// This is derived from the most recent drag position relative to the
+/// surface bounds and reset whenever there is no active drag gesture.
+///
+/// When autoscroll is non-none, the caller should setup a timer
+/// to periodically call autoscrollTick. The timer interval is up to the
+/// caller but reasonable defaults are approximately every 15 milliseconds.
+///
+/// This is used to implement selection above/below the viewport that
+/// wants to drag the viewport.
+pub const Autoscroll = lib.Enum(lib.target, &.{
+    "none",
+    "up",
+    "down",
+});
+
+/// The selection behavior for a click and subsequent drag.
+pub const Behavior = lib.Enum(lib.target, &.{
+    // Cell-granular drag selection. Press returns null to clear selection.
+    "cell",
+
+    // Word selection on press and word-granular drag selection.
+    "word",
+
+    // Line selection on press and line-granular drag selection.
+    "line",
+
+    // Semantic command output selection on press and drag.
+    "output",
+});
+
+/// Standard terminal selection behavior for single-, double-, and triple-clicks.
+///
+/// A single click uses cell behavior, which returns null on press so callers can
+/// clear any existing selection and then drag by cell. A double-click selects and
+/// drags by word. A triple-click selects and drags by line.
+pub const default_behaviors: [3]Behavior = .{ .cell, .word, .line };
+
+/// Distance from the top or bottom surface edge, in pixels, where dragging
+/// should request autoscroll. This preserves the historical 1px buffer used
+/// so fullscreen-edge drags can still trigger autoscroll.
+const autoscroll_buffer: f64 = 1;
+
+pub const init: SelectionGesture = .{
+    .left_click_pin = null,
+    .left_click_count = 0,
+    .left_click_time = null,
+    .left_click_behavior = .cell,
+    .left_click_screen = .primary,
+    .left_click_screen_generation = 0,
+    .left_click_xpos = 0,
+    .left_click_ypos = 0,
+    .left_click_dragged = false,
+    .left_drag_autoscroll = .none,
+};
+
+pub fn deinit(self: *SelectionGesture, t: *Terminal) void {
+    // Grab our pagelist that is associated with the pin. If it doesn't
+    // exist anymore then our tracked pin is already free.
+    const pin = self.left_click_pin orelse return;
+    if (t.screens.generation(self.left_click_screen) != self.left_click_screen_generation) return;
+    const screen = t.screens.get(self.left_click_screen) orelse return;
+    screen.pages.untrackPin(pin);
+}
+
+/// Reset any active gesture state and untrack the tracked click pin.
+///
+/// Use this for cancellation/abandonment, not for the ordinary left-button
+/// release path. `release` deliberately keeps the last press time/count so a
+/// following press can become a double- or triple-click; `reset` clears that
+/// sequence and makes the next press a fresh single click.
+///
+/// Examples of reset-worthy events are: mouse reporting taking over, pointer
+/// capture being lost, a surface/window being torn down, or another interaction
+/// mode deciding that text selection must stop immediately. If the active screen
+/// was already removed or recycled, this safely drops the stale reference without
+/// trying to untrack a pin from the wrong screen generation.
+pub fn reset(self: *SelectionGesture, t: *Terminal) void {
+    self.left_click_count = 0;
+    self.left_click_time = null;
+    self.left_click_behavior = .cell;
+    self.left_click_dragged = false;
+    self.left_drag_autoscroll = .none;
+    self.untrackPin(t);
+}
+
+/// Return the tracked left-click pin only if it still belongs to the current
+/// active screen instance.
+///
+/// This validates both the screen key and generation so a pin from a removed,
+/// recycled, or inactive screen is never exposed to callers. A null result means
+/// callers should treat the in-progress gesture as temporarily or permanently
+/// unable to produce a selection. For a normal drag this usually means "do
+/// nothing for this event"; for autoscroll it is treated as cancellation because
+/// a timer should not continue firing for a gesture that no longer has a valid
+/// anchor.
+pub fn validatedLeftClickPin(
+    self: *const SelectionGesture,
+    screens: *const ScreenSet,
+) ?*Pin {
+    const pin = self.left_click_pin orelse return null;
+    if (self.left_click_screen != screens.active_key) return null;
+    if (screens.generation(self.left_click_screen) != self.left_click_screen_generation) return null;
+    _ = screens.get(self.left_click_screen) orelse return null;
+    return pin;
+}
+
+pub const Press = struct {
+    /// The time when the press event occurred. Use a monotonic timer.
+    /// This can be null if you're on a system that doesn't support
+    /// time for some reason. In that case, we only support single clicks.
+    time: ?Time,
+
+    /// The cell where the click was.
+    ///
+    /// `press` stores a tracked copy of this pin. The caller does not need to
+    /// keep `p.pin` alive after the call returns, but the pin must belong to the
+    /// terminal's active screen when passed in.
+    pin: Pin,
+
+    /// The x/y value of the click relative to the surface with (0,0) being
+    /// top-left. This is used for distance detection for multi-clicks so
+    /// double/triple clicks too far away from each other will reset the click
+    /// count as well more accurate drag behaviors.
+    xpos: f64,
+    ypos: f64,
+
+    /// Maximum distance a click can be from the original click to register
+    /// as a repeat. If uncertain, set this to cell width.
+    max_distance: f64,
+
+    /// The maximum interval in nanoseconds that a press is considered
+    /// a repeat e.g. to record double/triple clicks.
+    repeat_interval: u64,
+
+    /// The codepoints that delimit words for double-click selection.
+    word_boundary_codepoints: []const u21,
+
+    /// Selection behaviors for single-, double-, and triple-clicks.
+    behaviors: *const [3]Behavior = &default_behaviors,
+};
+
+/// Record a press event and return the standard selection for this click.
+///
+/// If this press continues the existing click sequence, the click count is
+/// incremented up to three and the original anchor pin is kept. Otherwise, the
+/// previous gesture state is cleared and this press becomes the new anchor.
+/// The returned selection is untracked and represents the standard terminal
+/// click behavior for the resulting click count. The caller is responsible for
+/// applying it to the screen, usually with `Screen.select`, and for arranging
+/// any copy-on-select behavior.
+///
+/// Examples:
+///
+/// * first press: `left_click_count == 1`, defaults to cell behavior;
+/// * second nearby press within the repeat interval: `left_click_count == 2`,
+///   defaults to word behavior;
+/// * third nearby press within the repeat interval: `left_click_count == 3`,
+///   defaults to line behavior;
+/// * press after the interval, too far away, or after a screen generation
+///   change: starts over at `left_click_count == 1` and returns null.
+pub fn press(
+    self: *SelectionGesture,
+    t: *Terminal,
+    p: Press,
+) Allocator.Error!?Selection {
+    if (self.left_click_count > 0) {
+        if (self.pressRepeat(t, p)) {
+            // Successful repeat.
+            return self.pressSelection(t.screens.active, p);
+        } else |err| switch (err) {
+            error.PressRequiresReset => {},
+        }
+    }
+
+    // Initial click or the repeat failed for some reason such as
+    // the subsequent click being too far away.
+    try self.pressInitial(t, p);
+    return self.pressSelection(t.screens.active, p);
+}
+
+pub const Drag = struct {
+    /// The cell where the current drag position is. This is used
+    /// synchronously to calculate the selection and is not tracked.
+    pin: Pin,
+
+    /// The x/y value of the drag relative to the surface with (0,0) being
+    /// top-left.
+    xpos: f64,
+    ypos: f64,
+
+    /// True if the current drag should produce a rectangular selection.
+    rectangle: bool,
+
+    /// The codepoints that delimit words for double-click drag selection.
+    word_boundary_codepoints: []const u21,
+
+    /// Geometry required for selection threshold and autoscroll calculations.
+    geometry: Geometry,
+
+    /// Display geometry needed to translate surface-relative pointer positions
+    /// into selection behavior.
+    pub const Geometry = struct {
+        /// The number of columns in the rendered terminal grid.
+        columns: u32,
+
+        /// The width of one terminal cell in surface pixels.
+        cell_width: u32,
+
+        /// The left padding before the terminal grid begins, in surface pixels.
+        padding_left: u32,
+
+        /// The height of the rendered terminal surface in surface pixels.
+        screen_height: u32,
+    };
+};
+
+/// Record a drag event and return the current untracked drag selection.
+///
+/// The returned selection is untracked and represents the best selection for the
+/// terminal contents at the time of this call. The caller is responsible for
+/// applying it to the screen, usually with `Screen.select`, and for arranging any
+/// copy-on-select behavior. A null result means either there is no active
+/// selection gesture, the original press is no longer valid for the active
+/// screen, or the drag has not crossed the threshold required to select a cell.
+///
+/// This method also updates `left_click_dragged` and `left_drag_autoscroll`.
+/// If `left_drag_autoscroll` becomes `.up` or `.down`, the caller should start or
+/// keep a timer that calls `autoscrollTick` while the button remains pressed. If
+/// it becomes `.none`, the caller should stop that timer.
+///
+/// Normal terminal output and viewport movement between drag events are allowed:
+/// the tracked press pin follows the page list, and the drag pin is used only
+/// synchronously. Content-sensitive selections such as word and line selection
+/// are recalculated from the current active screen every time.
+pub fn drag(
+    self: *SelectionGesture,
+    t: *Terminal,
+    d: Drag,
+) ?Selection {
+    // If we aren't currently clicked then we don't do any dragging
+    // behavior.
+    if (self.left_click_count == 0) {
+        assert(self.left_drag_autoscroll == .none);
+        return null;
+    }
+
+    // Get our click pin. We get a validated pin because if our
+    // screen changed out from under us then we aren't actually
+    // clicking anymore.
+    const click_pin = self.validatedLeftClickPin(&t.screens) orelse return null;
+    if (!d.pin.eql(click_pin.*)) self.left_click_dragged = true;
+
+    // Determine if we should autoscroll. If our drag position is above
+    // the top, we go up. If its below the bottom we go down. Easy.
+    const max_y: f64 = @floatFromInt(d.geometry.screen_height);
+    self.left_drag_autoscroll = if (d.ypos <= autoscroll_buffer)
+        .up
+    else if (d.ypos > max_y - autoscroll_buffer)
+        .down
+    else
+        .none;
+
+    const selection = switch (self.left_click_behavior) {
+        .cell => dragSelection(
+            click_pin.*,
+            d.pin,
+            @intFromFloat(@max(0, self.left_click_xpos)),
+            @intFromFloat(@max(0, d.xpos)),
+            d.rectangle,
+            d.geometry,
+        ),
+
+        .word => dragSelectionWord(
+            t.screens.active,
+            click_pin.*,
+            d.pin,
+            d.word_boundary_codepoints,
+        ),
+
+        .line => dragSelectionLine(
+            t.screens.active,
+            click_pin.*,
+            d.pin,
+        ),
+
+        .output => dragSelectionOutput(
+            t.screens.active,
+            click_pin.*,
+            d.pin,
+        ),
+    };
+
+    // Same-cell cell selections can still become real selections when the drag
+    // crosses the within-cell threshold. Treat those as drags so callers don't
+    // also process click-only actions such as opening links.
+    if (self.left_click_behavior == .cell and selection != null) {
+        self.left_click_dragged = true;
+    }
+
+    return selection;
+}
+
+pub const AutoscrollTick = struct {
+    /// The viewport cell where the current drag position is. This is resolved
+    /// after the viewport is scrolled so the selection tracks the newly visible
+    /// row under the pointer.
+    viewport: point.Coordinate,
+
+    /// The x/y value of the drag relative to the surface with (0,0) being
+    /// top-left.
+    xpos: f64,
+    ypos: f64,
+
+    /// True if the current drag should produce a rectangular selection.
+    rectangle: bool,
+
+    /// The codepoints that delimit words for double-click drag selection.
+    word_boundary_codepoints: []const u21,
+
+    /// Geometry required for selection threshold and autoscroll calculations.
+    geometry: Drag.Geometry,
+};
+
+/// Record a selection autoscroll tick for the active left-click drag gesture.
+///
+/// This scrolls the viewport in the active autoscroll direction and then
+/// continues the drag at the provided viewport position. The viewport position
+/// is resolved to a pin after scrolling so the drag applies to the row now under
+/// the pointer.
+///
+/// This always scrolls the viewport by exactly one row in the current
+/// autoscroll direction. If you want to scroll by more, increase your
+/// tick rate.
+///
+/// If the original press pin no longer belongs to the active screen, this calls
+/// `reset` and returns null. That is a signal for the caller to stop its
+/// autoscroll timer and leave any existing terminal selection alone unless some
+/// other event says otherwise.
+pub fn autoscrollTick(
+    self: *SelectionGesture,
+    t: *Terminal,
+    tick: AutoscrollTick,
+) ?Selection {
+    if (self.left_click_count == 0) {
+        assert(self.left_drag_autoscroll == .none);
+        return null;
+    }
+
+    const delta: isize = switch (self.left_drag_autoscroll) {
+        .none => return null,
+        .up => -1,
+        .down => 1,
+    };
+
+    // If our click pin no longer belongs to the active screen, the gesture is
+    // no longer valid. Stop it so callers can stop their autoscroll timer
+    // without clearing the current selection as if this were a real drag.
+    _ = self.validatedLeftClickPin(&t.screens) orelse {
+        self.reset(t);
+        return null;
+    };
+
+    t.scrollViewport(.{ .delta = delta });
+
+    const pin = t.screens.active.pages.pin(.{ .viewport = tick.viewport }) orelse return null;
+    return self.drag(t, .{
+        .pin = pin,
+        .xpos = tick.xpos,
+        .ypos = tick.ypos,
+        .rectangle = tick.rectangle,
+        .word_boundary_codepoints = tick.word_boundary_codepoints,
+        .geometry = tick.geometry,
+    });
+}
+
+/// A pressure-based activation during an existing left-click gesture.
+///
+/// This is the terminal gesture model for platform features such as macOS
+/// force click / deep click on pressure-sensitive trackpads. It is not a
+/// distinct mouse button and it is not part of the normal single/double/triple
+/// click count sequence; it can only occur after a left press is already
+/// active.
+pub const DeepPress = struct {
+    /// The codepoints that delimit words for the word selection produced by
+    /// the deep press.
+    word_boundary_codepoints: []const u21,
+};
+
+/// Record a deep press event for the active left-click gesture.
+///
+/// A deep press is a force/pressure activation while the primary pointer is
+/// already down. Ghostty treats it like the platform text-selection affordance:
+/// select the word under the original press, then consume the gesture so
+/// further cursor movement while the button remains pressed does not drag or
+/// autoscroll the selection.
+///
+/// After a successful deep press, the click sequence is cleared and the tracked
+/// pin is untracked. The returned selection should be applied by the caller. A
+/// null result means there was no valid active left-click anchor, commonly
+/// because the screen changed or the gesture had already been cancelled.
+pub fn deepPress(
+    self: *SelectionGesture,
+    t: *Terminal,
+    p: DeepPress,
+) ?Selection {
+    const click_pin = self.validatedLeftClickPin(&t.screens) orelse return null;
+    const sel = t.screens.active.selectWord(
+        click_pin.*,
+        p.word_boundary_codepoints,
+    );
+
+    self.left_click_count = 0;
+    self.left_click_time = null;
+    self.left_click_behavior = .cell;
+    self.left_click_dragged = true;
+    self.left_drag_autoscroll = .none;
+    self.untrackPin(t);
+
+    return sel;
+}
+
+pub const Release = struct {
+    /// The cell where the release occurred, if the release position mapped to
+    /// a valid cell. This is used synchronously to update gesture state and is
+    /// not tracked.
+    pin: ?Pin,
+};
+
+/// Record a release event for the active left-click gesture.
+///
+/// This stops autoscroll and updates `left_click_dragged`, but it does not clear
+/// the click count or time. Keeping that state is what lets the next nearby press
+/// become a double- or triple-click. Call `reset` instead if the release should
+/// cancel the click sequence entirely.
+///
+/// Pass the release pin when the pointer position maps to a valid terminal cell.
+/// If it does not, pass null; the gesture then conservatively records that the
+/// pointer moved away from the original pressed cell. This is useful for callers
+/// that use `left_click_dragged` after release to decide whether a click should
+/// activate links or other hit targets.
+pub fn release(
+    self: *SelectionGesture,
+    t: *Terminal,
+    r: Release,
+) void {
+    if (self.left_click_count == 0) {
+        assert(self.left_drag_autoscroll == .none);
+        return;
+    }
+
+    if (r.pin) |release_pin| {
+        if (self.validatedLeftClickPin(&t.screens)) |click_pin| {
+            if (!release_pin.eql(click_pin.*)) self.left_click_dragged = true;
+        } else {
+            // If the original anchor is no longer valid, conservatively treat
+            // this as a drag/cancelled click so callers don't perform click-only
+            // actions on a different or recycled screen.
+            self.left_click_dragged = true;
+        }
+    } else {
+        self.left_click_dragged = true;
+    }
+    self.left_drag_autoscroll = .none;
+}
+
+fn pressInitial(
+    self: *SelectionGesture,
+    t: *Terminal,
+    p: Press,
+) Allocator.Error!void {
+    // Setup our pin first, reusing our existing pin if we can.
+    if (self.left_click_pin) |pin| {
+        if (comptime std.debug.runtime_safety) {
+            assert(self.left_click_screen == t.screens.active_key);
+            assert(self.left_click_screen_generation == t.screens.generation(t.screens.active_key));
+        }
+        pin.* = p.pin;
+    } else {
+        const screens: *const ScreenSet = &t.screens;
+        self.left_click_pin = try screens.active.pages.trackPin(p.pin);
+        errdefer comptime unreachable;
+        self.left_click_screen = screens.active_key;
+        self.left_click_screen_generation = screens.generation(screens.active_key);
+    }
+    errdefer comptime unreachable;
+    self.left_click_count = 1;
+    self.left_click_behavior = p.behaviors[0];
+    self.left_click_xpos = p.xpos;
+    self.left_click_ypos = p.ypos;
+    self.left_click_time = p.time;
+    self.left_click_dragged = false;
+    self.left_drag_autoscroll = .none;
+}
+
+fn pressRepeat(
+    self: *SelectionGesture,
+    t: *Terminal,
+    p: Press,
+) error{PressRequiresReset}!void {
+    errdefer {
+        self.left_click_count = 0;
+        self.left_click_behavior = .cell;
+        self.untrackPin(t);
+    }
+
+    // If too much time has passed then we always reset.
+    const time = p.time orelse return error.PressRequiresReset;
+    {
+        const prev_time = self.left_click_time orelse return error.PressRequiresReset;
+        const since = timeSince(time, prev_time);
+        if (since > p.repeat_interval) return error.PressRequiresReset;
+    }
+
+    // If the click is too far away from the initial click we can't continue.
+    const distance = @sqrt(
+        std.math.pow(f64, p.xpos - self.left_click_xpos, 2) +
+            std.math.pow(f64, p.ypos - self.left_click_ypos, 2),
+    );
+    if (distance > p.max_distance) return error.PressRequiresReset;
+
+    // If our prior click was on another screen then free and reset. "Another screen"
+    // doesn't just mean alt vs primary, it could mean an alt screen that was
+    // recycled since we free tracked pins on recycle.
+    const screens: *const ScreenSet = &t.screens;
+    if (self.left_click_screen != screens.active_key or
+        screens.generation(self.left_click_screen) !=
+            self.left_click_screen_generation)
+    {
+        // The error return will trigger the top-level errdefer which
+        // will reset our pin.
+        return error.PressRequiresReset;
+    }
+
+    self.left_click_time = time;
+    self.left_click_dragged = false;
+    self.left_drag_autoscroll = .none;
+    self.left_click_count = @min(
+        self.left_click_count + 1,
+        3, // We only support triple clicks max
+    );
+    self.left_click_behavior = p.behaviors[self.left_click_count - 1];
+}
+
+fn timeSince(time: Time, prev_time: Time) u64 {
+    if (comptime freestanding_wasm) return time -| prev_time;
+    return time.since(prev_time);
+}
+
+fn pressSelection(
+    self: *const SelectionGesture,
+    screen: *Screen,
+    p: Press,
+) ?Selection {
+    return switch (self.left_click_behavior) {
+        .cell => null,
+        .word => screen.selectWord(p.pin, p.word_boundary_codepoints),
+        .line => screen.selectLine(.{ .pin = p.pin }),
+        .output => screen.selectOutput(p.pin),
+    };
+}
+
+/// Calculates the appropriate selection given pins and pixel x positions for
+/// the click point and the drag point, as well as selection mode and geometry.
+fn dragSelection(
+    click_pin: Pin,
+    drag_pin: Pin,
+    click_x: u32,
+    drag_x: u32,
+    rectangle_selection: bool,
+    geometry: Drag.Geometry,
+) ?Selection {
+    // Explanation:
+    //
+    // # Normal selections
+    //
+    // ## Left-to-right selections
+    // - The clicked cell is included if it was clicked to the left of its
+    //   threshold point and the drag location is right of the threshold point.
+    // - The cell under the cursor (the "drag cell") is included if the drag
+    //   location is right of its threshold point.
+    //
+    // ## Right-to-left selections
+    // - The clicked cell is included if it was clicked to the right of its
+    //   threshold point and the drag location is left of the threshold point.
+    // - The cell under the cursor (the "drag cell") is included if the drag
+    //   location is left of its threshold point.
+    //
+    // # Rectangular selections
+    //
+    // Rectangular selections are handled similarly, except that
+    // entire columns are considered rather than individual cells.
+
+    // We only include cells in the selection if the threshold point lies
+    // between the start and end points of the selection. A threshold of
+    // 60% of the cell width was chosen empirically because it felt good.
+    const threshold_point: u32 = @intFromFloat(@round(
+        @as(f64, @floatFromInt(geometry.cell_width)) * 0.6,
+    ));
+
+    // We use this to clamp the pixel positions below.
+    const max_x = geometry.columns * geometry.cell_width - 1;
+
+    // We need to know how far across in the cell the drag pos is, so
+    // we subtract the padding and then take it modulo the cell width.
+    const drag_x_frac = @min(max_x, drag_x -| geometry.padding_left) % geometry.cell_width;
+
+    // We figure out the fractional part of the click x position similarly.
+    const click_x_frac = @min(max_x, click_x -| geometry.padding_left) % geometry.cell_width;
+
+    // Whether the click pin and drag pin are equal.
+    const same_pin = drag_pin.eql(click_pin);
+
+    // Whether or not the end point of our selection is before the start point.
+    const end_before_start = ebs: {
+        if (same_pin) {
+            break :ebs drag_x_frac < click_x_frac;
+        }
+
+        // Special handling for rectangular selections, we only use x position.
+        if (rectangle_selection) {
+            break :ebs switch (std.math.order(drag_pin.x, click_pin.x)) {
+                .eq => drag_x_frac < click_x_frac,
+                .lt => true,
+                .gt => false,
+            };
+        }
+
+        break :ebs drag_pin.before(click_pin);
+    };
+
+    // Whether or not the click pin cell
+    // should be included in the selection.
+    const include_click_cell = if (end_before_start)
+        click_x_frac >= threshold_point
+    else
+        click_x_frac < threshold_point;
+
+    // Whether or not the drag pin cell
+    // should be included in the selection.
+    const include_drag_cell = if (end_before_start)
+        drag_x_frac < threshold_point
+    else
+        drag_x_frac >= threshold_point;
+
+    // If the click cell should be included in the selection then it's the
+    // start, otherwise we get the previous or next cell to it depending on
+    // the type and direction of the selection.
+    const start_pin =
+        if (include_click_cell)
+            click_pin
+        else if (end_before_start)
+            if (rectangle_selection)
+                click_pin.leftClamp(1)
+            else
+                click_pin.leftWrap(1) orelse click_pin
+        else if (rectangle_selection)
+            click_pin.rightClamp(1)
+        else
+            click_pin.rightWrap(1) orelse click_pin;
+
+    // Likewise for the end pin with the drag cell.
+    const end_pin =
+        if (include_drag_cell)
+            drag_pin
+        else if (end_before_start)
+            if (rectangle_selection)
+                drag_pin.rightClamp(1)
+            else
+                drag_pin.rightWrap(1) orelse drag_pin
+        else if (rectangle_selection)
+            drag_pin.leftClamp(1)
+        else
+            drag_pin.leftWrap(1) orelse drag_pin;
+
+    // If the click cell is the same as the drag cell and the click cell
+    // shouldn't be included, or if the cells are adjacent such that the
+    // start or end pin becomes the other cell, and that cell should not
+    // be included, then we have no selection, so we set it to null.
+    //
+    // If in rectangular selection mode, we compare columns as well.
+    //
+    // TODO(qwerasd): this can/should probably be refactored, it's a bit
+    //                repetitive and does excess work in rectangle mode.
+    if ((!include_click_cell and same_pin) or
+        (!include_click_cell and rectangle_selection and click_pin.x == drag_pin.x) or
+        (!include_click_cell and end_pin.eql(click_pin)) or
+        (!include_click_cell and rectangle_selection and end_pin.x == click_pin.x) or
+        (!include_drag_cell and start_pin.eql(drag_pin)) or
+        (!include_drag_cell and rectangle_selection and start_pin.x == drag_pin.x))
+    {
+        return null;
+    }
+
+    // TODO: Clamp selection to the screen area, don't
+    //       let it extend past the last written row.
+
+    return .init(
+        start_pin,
+        end_pin,
+        rectangle_selection,
+    );
+}
+
+/// Calculates the appropriate word-wise selection for a double-click drag.
+fn dragSelectionWord(
+    screen: *Screen,
+    click_pin: Pin,
+    drag_pin: Pin,
+    boundary_codepoints: []const u21,
+) ?Selection {
+    // Get the word closest to our starting click.
+    const word_start = screen.selectWordBetween(
+        click_pin,
+        drag_pin,
+        boundary_codepoints,
+    ) orelse return null;
+
+    // Get the word closest to our current point.
+    const word_current = screen.selectWordBetween(
+        drag_pin,
+        click_pin,
+        boundary_codepoints,
+    ) orelse return null;
+
+    // If our current mouse position is before the starting position,
+    // then the selection start is the word nearest our current position.
+    return if (drag_pin.before(click_pin))
+        .init(
+            word_current.start(),
+            word_start.end(),
+            false,
+        )
+    else
+        .init(
+            word_start.start(),
+            word_current.end(),
+            false,
+        );
+}
+
+/// Calculates the appropriate line-wise selection for a triple-click drag.
+fn dragSelectionLine(
+    screen: *Screen,
+    click_pin: Pin,
+    drag_pin: Pin,
+) ?Selection {
+    // Get the line selection under our current drag point. If there isn't a
+    // line, do nothing.
+    const line = screen.selectLine(.{ .pin = drag_pin }) orelse return null;
+
+    // Get the selection under our click point. We first try to trim
+    // whitespace if we've selected a word. But if no word exists then
+    // we select the blank line.
+    const sel_ = screen.selectLine(.{ .pin = click_pin }) orelse
+        screen.selectLine(.{ .pin = click_pin, .whitespace = null });
+
+    var sel = sel_ orelse return null;
+    if (drag_pin.before(click_pin)) {
+        sel.startPtr().* = line.start();
+    } else {
+        sel.endPtr().* = line.end();
+    }
+    return sel;
+}
+
+/// Calculates the appropriate semantic-output-wise selection for an output
+/// drag. This expands from the output block under the click point to the output
+/// block under the current drag point. If the drag point is not output, keep the
+/// original output selection.
+fn dragSelectionOutput(
+    screen: *Screen,
+    click_pin: Pin,
+    drag_pin: Pin,
+) ?Selection {
+    var sel = screen.selectOutput(click_pin) orelse return null;
+    const current = screen.selectOutput(drag_pin) orelse return sel;
+
+    if (drag_pin.before(click_pin)) {
+        sel.startPtr().* = current.start();
+    } else {
+        sel.endPtr().* = current.end();
+    }
+    return sel;
+}
+
+fn untrackPin(self: *SelectionGesture, t: *Terminal) void {
+    // Can't untrack unless we have a pin.
+    const pin = self.left_click_pin orelse return;
+    self.left_click_pin = null;
+
+    // If the generation changed our pin is already invalid.
+    const screens: *const ScreenSet = &t.screens;
+    if (screens.generation(self.left_click_screen) != self.left_click_screen_generation) return;
+
+    // If we can't get a screen then its already freed.
+    const screen = screens.get(self.left_click_screen) orelse return;
+    screen.pages.untrackPin(pin);
+}
+
+fn testPress(t: *Terminal, x: u16, y: u32, time: ?std.time.Instant) Press {
+    return .{
+        .time = time,
+        .pin = t.screens.active.pages.pin(.{ .active = .{
+            .x = x,
+            .y = y,
+        } }).?,
+        .xpos = @floatFromInt(x),
+        .ypos = @floatFromInt(y),
+        .max_distance = 1,
+        .repeat_interval = std.math.maxInt(u64),
+        .word_boundary_codepoints = &.{},
+    };
+}
+
+fn testDrag(t: *Terminal, x: u16, y: u32, xpos: f64, ypos: f64) Drag {
+    return .{
+        .pin = t.screens.active.pages.pin(.{ .active = .{
+            .x = x,
+            .y = y,
+        } }).?,
+        .xpos = xpos,
+        .ypos = ypos,
+        .rectangle = false,
+        .word_boundary_codepoints = &.{},
+        .geometry = .{
+            .columns = 5,
+            .cell_width = 10,
+            .padding_left = 0,
+            .screen_height = 100,
+        },
+    };
+}
+
+fn testAutoscrollTick(
+    viewport: point.Coordinate,
+    xpos: f64,
+    ypos: f64,
+) AutoscrollTick {
+    return .{
+        .viewport = viewport,
+        .xpos = xpos,
+        .ypos = ypos,
+        .rectangle = false,
+        .word_boundary_codepoints = &.{},
+        .geometry = .{
+            .columns = 5,
+            .cell_width = 10,
+            .padding_left = 0,
+            .screen_height = 100,
+        },
+    };
+}
+
+fn testPin(t: *Terminal, x: u16, y: u32) Pin {
+    return t.screens.active.pages.pin(.{ .active = .{
+        .x = x,
+        .y = y,
+    } }).?;
+}
+
+/// Utility function for the unit tests for drag selection logic.
+///
+/// Tests a click and drag on a 10x5 cell grid, x positions are given in
+/// fractional cells, e.g. 3.1 would be 10% through the cell at x = 3.
+///
+/// NOTE: The geometry tested with has 10px wide cells, meaning only one digit
+///       after the decimal place has any meaning, e.g. 3.14 is equal to 3.1.
+///
+/// The provided start_x/y and end_x/y are the expected start and end points
+/// of the resulting selection.
+fn testDragSelection(
+    click_x: f64,
+    click_y: u32,
+    drag_x: f64,
+    drag_y: u32,
+    start_x: u16,
+    start_y: u32,
+    end_x: u16,
+    end_y: u32,
+    rect: bool,
+) !void {
+    assert(@import("builtin").is_test);
+
+    // Our screen size is 10x5 cells that are
+    // 10x20 px, with 5px padding on all sides.
+    const geometry: Drag.Geometry = .{
+        .columns = 10,
+        .cell_width = 10,
+        .padding_left = 5,
+        .screen_height = 110,
+    };
+    var screen = try Screen.init(testing.allocator, .{ .cols = 10, .rows = 5, .max_scrollback = 0 });
+    defer screen.deinit();
+
+    const click_pin = screen.pages.pin(.{
+        .viewport = .{ .x = @intFromFloat(@floor(click_x)), .y = click_y },
+    }) orelse unreachable;
+    const drag_pin = screen.pages.pin(.{
+        .viewport = .{ .x = @intFromFloat(@floor(drag_x)), .y = drag_y },
+    }) orelse unreachable;
+
+    const cell_width_f64: f64 = @floatFromInt(geometry.cell_width);
+    const click_x_pos: u32 =
+        @as(u32, @intFromFloat(@floor(click_x * cell_width_f64))) +
+        geometry.padding_left;
+    const drag_x_pos: u32 =
+        @as(u32, @intFromFloat(@floor(drag_x * cell_width_f64))) +
+        geometry.padding_left;
+
+    const start_pin = screen.pages.pin(.{
+        .viewport = .{ .x = start_x, .y = start_y },
+    }) orelse unreachable;
+    const end_pin = screen.pages.pin(.{
+        .viewport = .{ .x = end_x, .y = end_y },
+    }) orelse unreachable;
+
+    try testing.expectEqualDeep(Selection{
+        .bounds = .{ .untracked = .{
+            .start = start_pin,
+            .end = end_pin,
+        } },
+        .rectangle = rect,
+    }, dragSelection(
+        click_pin,
+        drag_pin,
+        click_x_pos,
+        drag_x_pos,
+        rect,
+        geometry,
+    ));
+}
+
+/// Like `testDragSelection` but checks that the resulting selection is null.
+///
+/// See `testDragSelection` for more details.
+fn testDragSelectionIsNull(
+    click_x: f64,
+    click_y: u32,
+    drag_x: f64,
+    drag_y: u32,
+    rect: bool,
+) !void {
+    assert(@import("builtin").is_test);
+
+    // Our screen size is 10x5 cells that are
+    // 10x20 px, with 5px padding on all sides.
+    const geometry: Drag.Geometry = .{
+        .columns = 10,
+        .cell_width = 10,
+        .padding_left = 5,
+        .screen_height = 110,
+    };
+    var screen = try Screen.init(testing.allocator, .{ .cols = 10, .rows = 5, .max_scrollback = 0 });
+    defer screen.deinit();
+
+    const click_pin = screen.pages.pin(.{
+        .viewport = .{ .x = @intFromFloat(@floor(click_x)), .y = click_y },
+    }) orelse unreachable;
+    const drag_pin = screen.pages.pin(.{
+        .viewport = .{ .x = @intFromFloat(@floor(drag_x)), .y = drag_y },
+    }) orelse unreachable;
+
+    const cell_width_f64: f64 = @floatFromInt(geometry.cell_width);
+    const click_x_pos: u32 =
+        @as(u32, @intFromFloat(@floor(click_x * cell_width_f64))) +
+        geometry.padding_left;
+    const drag_x_pos: u32 =
+        @as(u32, @intFromFloat(@floor(drag_x * cell_width_f64))) +
+        geometry.padding_left;
+
+    try testing.expectEqual(
+        null,
+        dragSelection(
+            click_pin,
+            drag_pin,
+            click_x_pos,
+            drag_x_pos,
+            rect,
+            geometry,
+        ),
+    );
+}
+
+test "SelectionGesture drag selection logic" {
+    // We disable format to make these easier to
+    // read by pairing sets of coordinates per line.
+    // zig fmt: off
+
+    // -- LTR
+    // single cell selection
+    try testDragSelection(
+        3.0, 3, // click
+        3.9, 3, // drag
+        3, 3, // expected start
+        3, 3, // expected end
+        false, // regular selection
+    );
+    // including click and drag pin cells
+    try testDragSelection(
+        3.0, 3, // click
+        5.9, 3, // drag
+        3, 3, // expected start
+        5, 3, // expected end
+        false, // regular selection
+    );
+    // including click pin cell but not drag pin cell
+    try testDragSelection(
+        3.0, 3, // click
+        5.0, 3, // drag
+        3, 3, // expected start
+        4, 3, // expected end
+        false, // regular selection
+    );
+    // including drag pin cell but not click pin cell
+    try testDragSelection(
+        3.9, 3, // click
+        5.9, 3, // drag
+        4, 3, // expected start
+        5, 3, // expected end
+        false, // regular selection
+    );
+    // including neither click nor drag pin cells
+    try testDragSelection(
+        3.9, 3, // click
+        5.0, 3, // drag
+        4, 3, // expected start
+        4, 3, // expected end
+        false, // regular selection
+    );
+    // empty selection (single cell on only left half)
+    try testDragSelectionIsNull(
+        3.0, 3, // click
+        3.1, 3, // drag
+        false, // regular selection
+    );
+    // empty selection (single cell on only right half)
+    try testDragSelectionIsNull(
+        3.8, 3, // click
+        3.9, 3, // drag
+        false, // regular selection
+    );
+    // empty selection (between two cells, not crossing threshold)
+    try testDragSelectionIsNull(
+        3.9, 3, // click
+        4.0, 3, // drag
+        false, // regular selection
+    );
+
+    // -- RTL
+    // single cell selection
+    try testDragSelection(
+        3.9, 3, // click
+        3.0, 3, // drag
+        3, 3, // expected start
+        3, 3, // expected end
+        false, // regular selection
+    );
+    // including click and drag pin cells
+    try testDragSelection(
+        5.9, 3, // click
+        3.0, 3, // drag
+        5, 3, // expected start
+        3, 3, // expected end
+        false, // regular selection
+    );
+    // including click pin cell but not drag pin cell
+    try testDragSelection(
+        5.9, 3, // click
+        3.9, 3, // drag
+        5, 3, // expected start
+        4, 3, // expected end
+        false, // regular selection
+    );
+    // including drag pin cell but not click pin cell
+    try testDragSelection(
+        5.0, 3, // click
+        3.0, 3, // drag
+        4, 3, // expected start
+        3, 3, // expected end
+        false, // regular selection
+    );
+    // including neither click nor drag pin cells
+    try testDragSelection(
+        5.0, 3, // click
+        3.9, 3, // drag
+        4, 3, // expected start
+        4, 3, // expected end
+        false, // regular selection
+    );
+    // empty selection (single cell on only left half)
+    try testDragSelectionIsNull(
+        3.1, 3, // click
+        3.0, 3, // drag
+        false, // regular selection
+    );
+    // empty selection (single cell on only right half)
+    try testDragSelectionIsNull(
+        3.9, 3, // click
+        3.8, 3, // drag
+        false, // regular selection
+    );
+    // empty selection (between two cells, not crossing threshold)
+    try testDragSelectionIsNull(
+        4.0, 3, // click
+        3.9, 3, // drag
+        false, // regular selection
+    );
+
+    // -- Wrapping
+    // LTR, wrap excluded cells
+    try testDragSelection(
+        9.9, 2, // click
+        0.0, 4, // drag
+        0, 3, // expected start
+        9, 3, // expected end
+        false, // regular selection
+    );
+    // RTL, wrap excluded cells
+    try testDragSelection(
+        0.0, 4, // click
+        9.9, 2, // drag
+        9, 3, // expected start
+        0, 3, // expected end
+        false, // regular selection
+    );
+}
+
+test "SelectionGesture rectangle drag selection logic" {
+    // We disable format to make these easier to
+    // read by pairing sets of coordinates per line.
+    // zig fmt: off
+
+    // -- LTR
+    // single column selection
+    try testDragSelection(
+        3.0, 2, // click
+        3.9, 4, // drag
+        3, 2, // expected start
+        3, 4, // expected end
+        true, //rectangle selection
+    );
+    // including click and drag pin columns
+    try testDragSelection(
+        3.0, 2, // click
+        5.9, 4, // drag
+        3, 2, // expected start
+        5, 4, // expected end
+        true, //rectangle selection
+    );
+    // including click pin column but not drag pin column
+    try testDragSelection(
+        3.0, 2, // click
+        5.0, 4, // drag
+        3, 2, // expected start
+        4, 4, // expected end
+        true, //rectangle selection
+    );
+    // including drag pin column but not click pin column
+    try testDragSelection(
+        3.9, 2, // click
+        5.9, 4, // drag
+        4, 2, // expected start
+        5, 4, // expected end
+        true, //rectangle selection
+    );
+    // including neither click nor drag pin columns
+    try testDragSelection(
+        3.9, 2, // click
+        5.0, 4, // drag
+        4, 2, // expected start
+        4, 4, // expected end
+        true, //rectangle selection
+    );
+    // empty selection (single column on only left half)
+    try testDragSelectionIsNull(
+        3.0, 2, // click
+        3.1, 4, // drag
+        true, //rectangle selection
+    );
+    // empty selection (single column on only right half)
+    try testDragSelectionIsNull(
+        3.8, 2, // click
+        3.9, 4, // drag
+        true, //rectangle selection
+    );
+    // empty selection (between two columns, not crossing threshold)
+    try testDragSelectionIsNull(
+        3.9, 2, // click
+        4.0, 4, // drag
+        true, //rectangle selection
+    );
+
+    // -- RTL
+    // single column selection
+    try testDragSelection(
+        3.9, 2, // click
+        3.0, 4, // drag
+        3, 2, // expected start
+        3, 4, // expected end
+        true, //rectangle selection
+    );
+    // including click and drag pin columns
+    try testDragSelection(
+        5.9, 2, // click
+        3.0, 4, // drag
+        5, 2, // expected start
+        3, 4, // expected end
+        true, //rectangle selection
+    );
+    // including click pin column but not drag pin column
+    try testDragSelection(
+        5.9, 2, // click
+        3.9, 4, // drag
+        5, 2, // expected start
+        4, 4, // expected end
+        true, //rectangle selection
+    );
+    // including drag pin column but not click pin column
+    try testDragSelection(
+        5.0, 2, // click
+        3.0, 4, // drag
+        4, 2, // expected start
+        3, 4, // expected end
+        true, //rectangle selection
+    );
+    // including neither click nor drag pin columns
+    try testDragSelection(
+        5.0, 2, // click
+        3.9, 4, // drag
+        4, 2, // expected start
+        4, 4, // expected end
+        true, //rectangle selection
+    );
+    // empty selection (single column on only left half)
+    try testDragSelectionIsNull(
+        3.1, 2, // click
+        3.0, 4, // drag
+        true, //rectangle selection
+    );
+    // empty selection (single column on only right half)
+    try testDragSelectionIsNull(
+        3.9, 2, // click
+        3.8, 4, // drag
+        true, //rectangle selection
+    );
+    // empty selection (between two columns, not crossing threshold)
+    try testDragSelectionIsNull(
+        4.0, 2, // click
+        3.9, 4, // drag
+        true, //rectangle selection
+    );
+
+    // -- Wrapping
+    // LTR, do not wrap
+    try testDragSelection(
+        9.9, 2, // click
+        0.0, 4, // drag
+        9, 2, // expected start
+        0, 4, // expected end
+        true, //rectangle selection
+    );
+    // RTL, do not wrap
+    try testDragSelection(
+        0.0, 4, // click
+        9.9, 2, // drag
+        0, 4, // expected start
+        9, 2, // expected end
+        true, //rectangle selection
+    );
+}
+
+test "SelectionGesture press records initial click" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 5, .rows = 5 });
+    defer t.deinit(testing.allocator);
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    const time = try std.time.Instant.now();
+    _ = try gesture.press(&t, testPress(&t, 1, 2, time));
+
+    try testing.expectEqual(@as(u3, 1), gesture.left_click_count);
+    try testing.expectEqual(time, gesture.left_click_time.?);
+    try testing.expectEqual(@as(f64, 1), gesture.left_click_xpos);
+    try testing.expectEqual(@as(f64, 2), gesture.left_click_ypos);
+    try testing.expectEqual(false, gesture.left_click_dragged);
+}
+
+test "SelectionGesture press returns standard click selections" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 20, .rows = 5 });
+    defer t.deinit(testing.allocator);
+    try t.printString("alpha beta\none two");
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    const time = try std.time.Instant.now();
+    var event = testPress(&t, 1, 0, time);
+    event.word_boundary_codepoints = &.{ ' ' };
+
+    try testing.expectEqual(null, try gesture.press(&t, event));
+
+    try testing.expectEqualDeep(Selection.init(
+        testPin(&t, 0, 0),
+        testPin(&t, 4, 0),
+        false,
+    ), (try gesture.press(&t, event)).?);
+
+    try testing.expectEqualDeep(Selection.init(
+        testPin(&t, 0, 0),
+        testPin(&t, 9, 0),
+        false,
+    ), (try gesture.press(&t, event)).?);
+}
+
+test "SelectionGesture press behaviors choose press and drag behavior" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 20, .rows = 5 });
+    defer t.deinit(testing.allocator);
+    try t.printString("alpha beta\none two\nthree four");
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    const time = try std.time.Instant.now();
+    var event = testPress(&t, 1, 0, time);
+    event.behaviors = &.{ .cell, .line, .word };
+    event.word_boundary_codepoints = &.{ ' ' };
+
+    _ = try gesture.press(&t, event);
+    try testing.expectEqual(.cell, gesture.left_click_behavior);
+
+    const double_click = (try gesture.press(&t, event)).?;
+    try testing.expectEqual(.line, gesture.left_click_behavior);
+    try testing.expectEqualDeep(Selection.init(
+        testPin(&t, 0, 0),
+        testPin(&t, 9, 0),
+        false,
+    ), double_click);
+
+    const line_drag = gesture.drag(&t, testDrag(&t, 2, 2, 20, 50)).?;
+    try testing.expectEqualDeep(Selection.init(
+        testPin(&t, 0, 0),
+        testPin(&t, 9, 2),
+        false,
+    ), line_drag);
+}
+
+test "SelectionGesture output behavior selects and drags semantic output" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 10, .rows = 6 });
+    defer t.deinit(testing.allocator);
+
+    const screen = t.screens.active;
+    screen.cursorSetSemanticContent(.output);
+    try screen.testWriteString("out1\n");
+    screen.cursorSetSemanticContent(.{ .prompt = .initial });
+    try screen.testWriteString("$ ");
+    screen.cursorSetSemanticContent(.{ .input = .clear_explicit });
+    try screen.testWriteString("cmd\n");
+    screen.cursorSetSemanticContent(.output);
+    try screen.testWriteString("out2");
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    var event = testPress(&t, 1, 0, try std.time.Instant.now());
+    event.behaviors = &.{ .output, .word, .line };
+
+    const press_selection = (try gesture.press(&t, event)).?;
+    try testing.expectEqual(.output, gesture.left_click_behavior);
+    try testing.expectEqualDeep(Selection.init(
+        testPin(&t, 0, 0),
+        testPin(&t, 3, 0),
+        false,
+    ), press_selection);
+
+    const output_drag = gesture.drag(&t, testDrag(&t, 1, 2, 10, 50)).?;
+    try testing.expectEqualDeep(Selection.init(
+        testPin(&t, 0, 0),
+        testPin(&t, 3, 2),
+        false,
+    ), output_drag);
+}
+
+test "SelectionGesture drag returns selection and records autoscroll" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 5, .rows = 5 });
+    defer t.deinit(testing.allocator);
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    var press_event = testPress(&t, 1, 1, try std.time.Instant.now());
+    press_event.xpos = 10;
+    _ = try gesture.press(&t, press_event);
+
+    const sel = gesture.drag(&t, testDrag(&t, 3, 1, 39, 50)).?;
+    try testing.expectEqual(.none, gesture.left_drag_autoscroll);
+    try testing.expectEqual(true, gesture.left_click_dragged);
+
+    try testing.expectEqualDeep(Selection.init(
+        t.screens.active.pages.pin(.{ .active = .{ .x = 1, .y = 1 } }).?,
+        t.screens.active.pages.pin(.{ .active = .{ .x = 3, .y = 1 } }).?,
+        false,
+    ), sel);
+
+    _ = gesture.drag(&t, testDrag(&t, 3, 1, 39, 1));
+    try testing.expectEqual(.up, gesture.left_drag_autoscroll);
+
+    _ = gesture.drag(&t, testDrag(&t, 3, 1, 39, 100));
+    try testing.expectEqual(.down, gesture.left_drag_autoscroll);
+}
+
+test "SelectionGesture release clears autoscroll and records drag" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 5, .rows = 5 });
+    defer t.deinit(testing.allocator);
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    _ = try gesture.press(&t, testPress(&t, 1, 1, try std.time.Instant.now()));
+    try testing.expectEqual(false, gesture.left_click_dragged);
+
+    _ = gesture.drag(&t, testDrag(&t, 1, 1, 10, 1));
+    try testing.expectEqual(.up, gesture.left_drag_autoscroll);
+    try testing.expectEqual(false, gesture.left_click_dragged);
+
+    gesture.release(&t, .{
+        .pin = testPin(&t, 2, 1),
+    });
+    try testing.expectEqual(.none, gesture.left_drag_autoscroll);
+    try testing.expectEqual(true, gesture.left_click_dragged);
+}
+
+test "SelectionGesture release with invalidated click records drag" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 5, .rows = 5 });
+    defer t.deinit(testing.allocator);
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    _ = try gesture.press(&t, testPress(&t, 1, 1, try std.time.Instant.now()));
+    try testing.expectEqual(false, gesture.left_click_dragged);
+
+    _ = try t.screens.getInit(testing.allocator, .alternate, .{
+        .cols = t.cols,
+        .rows = t.rows,
+    });
+    t.screens.switchTo(.alternate);
+
+    gesture.release(&t, .{ .pin = testPin(&t, 1, 1) });
+    try testing.expectEqual(true, gesture.left_click_dragged);
+    try testing.expectEqual(.none, gesture.left_drag_autoscroll);
+}
+
+test "SelectionGesture same-cell threshold selection records drag" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 5, .rows = 5 });
+    defer t.deinit(testing.allocator);
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    var press_event = testPress(&t, 1, 1, try std.time.Instant.now());
+    press_event.xpos = 10;
+    _ = try gesture.press(&t, press_event);
+    try testing.expectEqual(false, gesture.left_click_dragged);
+
+    const sel = gesture.drag(&t, testDrag(&t, 1, 1, 19, 50)).?;
+    try testing.expectEqual(true, gesture.left_click_dragged);
+    try testing.expectEqualDeep(Selection.init(
+        testPin(&t, 1, 1),
+        testPin(&t, 1, 1),
+        false,
+    ), sel);
+}
+
+test "SelectionGesture drag without press returns null" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 5, .rows = 5 });
+    defer t.deinit(testing.allocator);
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    try testing.expectEqual(null, gesture.drag(&t, testDrag(&t, 1, 1, 10, 50)));
+    try testing.expectEqual(.none, gesture.left_drag_autoscroll);
+}
+
+test "SelectionGesture drag autoscroll edge boundaries" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 5, .rows = 5 });
+    defer t.deinit(testing.allocator);
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    var press_event = testPress(&t, 1, 1, try std.time.Instant.now());
+    press_event.xpos = 10;
+    _ = try gesture.press(&t, press_event);
+
+    _ = gesture.drag(&t, testDrag(&t, 2, 1, 20, 1));
+    try testing.expectEqual(.up, gesture.left_drag_autoscroll);
+
+    _ = gesture.drag(&t, testDrag(&t, 2, 1, 20, 1.1));
+    try testing.expectEqual(.none, gesture.left_drag_autoscroll);
+
+    _ = gesture.drag(&t, testDrag(&t, 2, 1, 20, 99));
+    try testing.expectEqual(.none, gesture.left_drag_autoscroll);
+
+    _ = gesture.drag(&t, testDrag(&t, 2, 1, 20, 99.1));
+    try testing.expectEqual(.down, gesture.left_drag_autoscroll);
+}
+
+test "SelectionGesture autoscroll tick scrolls and continues drag" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 5, .rows = 5 });
+    defer t.deinit(testing.allocator);
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    var press_event = testPress(&t, 1, 1, try std.time.Instant.now());
+    press_event.xpos = 10;
+    _ = try gesture.press(&t, press_event);
+
+    _ = gesture.drag(&t, testDrag(&t, 3, 1, 39, 100));
+    try testing.expectEqual(.down, gesture.left_drag_autoscroll);
+
+    const sel = gesture.autoscrollTick(&t, testAutoscrollTick(.{ .x = 3, .y = 2 }, 39, 100)).?;
+    try testing.expectEqual(.down, gesture.left_drag_autoscroll);
+    try testing.expectEqual(true, gesture.left_click_dragged);
+    try testing.expectEqualDeep(Selection.init(
+        testPin(&t, 1, 1),
+        testPin(&t, 3, 2),
+        false,
+    ), sel);
+}
+
+test "SelectionGesture autoscroll tick resolves drag pin after scrolling" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 5, .rows = 3, .max_scrollback = 10 });
+    defer t.deinit(testing.allocator);
+    try t.printString("1111\n2222\n3333\n4444\n5555");
+    t.scrollViewport(.{ .delta = -2 });
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    var press_event = testPress(&t, 1, 1, try std.time.Instant.now());
+    press_event.xpos = 10;
+    _ = try gesture.press(&t, press_event);
+
+    _ = gesture.drag(&t, testDrag(&t, 3, 2, 39, 100));
+    try testing.expectEqual(.down, gesture.left_drag_autoscroll);
+
+    const viewport: point.Coordinate = .{ .x = 3, .y = 2 };
+    const pre_scroll_pin = t.screens.active.pages.pin(.{ .viewport = viewport }).?;
+    const sel = gesture.autoscrollTick(&t, testAutoscrollTick(viewport, 39, 100)).?;
+    const post_scroll_pin = t.screens.active.pages.pin(.{ .viewport = viewport }).?;
+
+    try testing.expect(!pre_scroll_pin.eql(post_scroll_pin));
+    try testing.expectEqualDeep(Selection.init(
+        testPin(&t, 1, 1),
+        post_scroll_pin,
+        false,
+    ), sel);
+}
+
+test "SelectionGesture autoscroll tick stops with invalidated click" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 5, .rows = 5 });
+    defer t.deinit(testing.allocator);
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    var press_event = testPress(&t, 1, 1, try std.time.Instant.now());
+    press_event.xpos = 10;
+    _ = try gesture.press(&t, press_event);
+
+    _ = gesture.drag(&t, testDrag(&t, 2, 1, 20, 1));
+    try testing.expectEqual(.up, gesture.left_drag_autoscroll);
+
+    _ = try t.screens.getInit(testing.allocator, .alternate, .{
+        .cols = t.cols,
+        .rows = t.rows,
+    });
+    t.screens.switchTo(.alternate);
+
+    try testing.expectEqual(null, gesture.autoscrollTick(&t, testAutoscrollTick(.{ .x = 2, .y = 1 }, 20, 1)));
+    try testing.expectEqual(.none, gesture.left_drag_autoscroll);
+    try testing.expectEqual(@as(u3, 0), gesture.left_click_count);
+}
+
+test "SelectionGesture deep press selects word and consumes drag" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 20, .rows = 5 });
+    defer t.deinit(testing.allocator);
+    try t.printString("alpha beta");
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    _ = try gesture.press(&t, testPress(&t, 1, 0, try std.time.Instant.now()));
+    _ = gesture.drag(&t, testDrag(&t, 1, 0, 10, 1));
+    try testing.expectEqual(.up, gesture.left_drag_autoscroll);
+
+    const sel = gesture.deepPress(&t, .{
+        .word_boundary_codepoints = &.{ ' ' },
+    }).?;
+
+    try testing.expectEqualDeep(Selection.init(
+        testPin(&t, 0, 0),
+        testPin(&t, 4, 0),
+        false,
+    ), sel);
+    try testing.expectEqual(@as(u3, 0), gesture.left_click_count);
+    try testing.expectEqual(@as(?std.time.Instant, null), gesture.left_click_time);
+    try testing.expectEqual(true, gesture.left_click_dragged);
+    try testing.expectEqual(.none, gesture.left_drag_autoscroll);
+    try testing.expect(gesture.left_click_pin == null);
+
+    try testing.expectEqual(null, gesture.drag(&t, testDrag(&t, 7, 0, 70, 50)));
+    gesture.release(&t, .{ .pin = testPin(&t, 7, 0) });
+    try testing.expectEqual(true, gesture.left_click_dragged);
+}
+
+test "SelectionGesture drag with invalidated click returns null" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 5, .rows = 5 });
+    defer t.deinit(testing.allocator);
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    var press_event = testPress(&t, 1, 1, try std.time.Instant.now());
+    press_event.xpos = 10;
+    _ = try gesture.press(&t, press_event);
+
+    _ = gesture.drag(&t, testDrag(&t, 2, 1, 20, 1));
+    try testing.expectEqual(.up, gesture.left_drag_autoscroll);
+
+    _ = try t.screens.getInit(testing.allocator, .alternate, .{
+        .cols = t.cols,
+        .rows = t.rows,
+    });
+    t.screens.switchTo(.alternate);
+
+    try testing.expectEqual(null, gesture.drag(&t, testDrag(&t, 2, 1, 20, 50)));
+    try testing.expectEqual(.up, gesture.left_drag_autoscroll);
+}
+
+test "SelectionGesture double-click drag selects by word" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 20, .rows = 5 });
+    defer t.deinit(testing.allocator);
+    try t.printString("alpha beta gamma");
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    const time = try std.time.Instant.now();
+    _ = try gesture.press(&t, testPress(&t, 1, 0, time));
+    _ = try gesture.press(&t, testPress(&t, 1, 0, time));
+
+    var drag_event = testDrag(&t, 7, 0, 70, 50);
+    drag_event.word_boundary_codepoints = &.{ ' ' };
+    const sel = gesture.drag(&t, drag_event).?;
+
+    try testing.expectEqualDeep(Selection.init(
+        testPin(&t, 0, 0),
+        testPin(&t, 9, 0),
+        false,
+    ), sel);
+}
+
+test "SelectionGesture double-click drag selects by word backwards" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 20, .rows = 5 });
+    defer t.deinit(testing.allocator);
+    try t.printString("alpha beta gamma");
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    const time = try std.time.Instant.now();
+    _ = try gesture.press(&t, testPress(&t, 7, 0, time));
+    _ = try gesture.press(&t, testPress(&t, 7, 0, time));
+
+    var drag_event = testDrag(&t, 1, 0, 10, 50);
+    drag_event.word_boundary_codepoints = &.{ ' ' };
+    const sel = gesture.drag(&t, drag_event).?;
+
+    try testing.expectEqualDeep(Selection.init(
+        testPin(&t, 0, 0),
+        testPin(&t, 9, 0),
+        false,
+    ), sel);
+}
+
+test "SelectionGesture double-click drag on empty cell selects nearest word" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 20, .rows = 5 });
+    defer t.deinit(testing.allocator);
+    try t.printString("alpha beta");
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    const time = try std.time.Instant.now();
+    _ = try gesture.press(&t, testPress(&t, 1, 0, time));
+    _ = try gesture.press(&t, testPress(&t, 1, 0, time));
+
+    var drag_event = testDrag(&t, 15, 0, 150, 50);
+    drag_event.word_boundary_codepoints = &.{ ' ' };
+    const sel = gesture.drag(&t, drag_event).?;
+
+    try testing.expectEqualDeep(Selection.init(
+        testPin(&t, 0, 0),
+        testPin(&t, 9, 0),
+        false,
+    ), sel);
+}
+
+test "SelectionGesture triple-click drag selects by line" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 20, .rows = 5 });
+    defer t.deinit(testing.allocator);
+    try t.printString("alpha beta\none two\nthree four");
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    const time = try std.time.Instant.now();
+    _ = try gesture.press(&t, testPress(&t, 1, 0, time));
+    _ = try gesture.press(&t, testPress(&t, 1, 0, time));
+    _ = try gesture.press(&t, testPress(&t, 1, 0, time));
+
+    const sel = gesture.drag(&t, testDrag(&t, 2, 2, 20, 50)).?;
+
+    try testing.expectEqualDeep(Selection.init(
+        testPin(&t, 0, 0),
+        testPin(&t, 9, 2),
+        false,
+    ), sel);
+}
+
+test "SelectionGesture triple-click drag selects by line backwards" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 20, .rows = 5 });
+    defer t.deinit(testing.allocator);
+    try t.printString("alpha beta\none two\nthree four");
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    const time = try std.time.Instant.now();
+    _ = try gesture.press(&t, testPress(&t, 2, 2, time));
+    _ = try gesture.press(&t, testPress(&t, 2, 2, time));
+    _ = try gesture.press(&t, testPress(&t, 2, 2, time));
+
+    const sel = gesture.drag(&t, testDrag(&t, 1, 0, 10, 50)).?;
+
+    try testing.expectEqualDeep(Selection.init(
+        testPin(&t, 0, 0),
+        testPin(&t, 9, 2),
+        false,
+    ), sel);
+}
+
+test "SelectionGesture repeat increments click count" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 5, .rows = 5 });
+    defer t.deinit(testing.allocator);
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    const time = try std.time.Instant.now();
+    _ = try gesture.press(&t, testPress(&t, 1, 1, time));
+    _ = try gesture.press(&t, testPress(&t, 1, 1, time));
+
+    try testing.expectEqual(@as(u3, 2), gesture.left_click_count);
+}
+
+test "SelectionGesture repeat clamps at triple click" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 5, .rows = 5 });
+    defer t.deinit(testing.allocator);
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    const time = try std.time.Instant.now();
+    for (0..4) |_| _ = try gesture.press(&t, testPress(&t, 1, 1, time));
+
+    try testing.expectEqual(@as(u3, 3), gesture.left_click_count);
+}
+
+test "SelectionGesture null initial time stays single click" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 5, .rows = 5 });
+    defer t.deinit(testing.allocator);
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    _ = try gesture.press(&t, testPress(&t, 1, 1, null));
+    _ = try gesture.press(&t, testPress(&t, 1, 1, try std.time.Instant.now()));
+
+    try testing.expectEqual(@as(u3, 1), gesture.left_click_count);
+    try testing.expect(gesture.left_click_time != null);
+}
+
+test "SelectionGesture null repeat time stays single click" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 5, .rows = 5 });
+    defer t.deinit(testing.allocator);
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    _ = try gesture.press(&t, testPress(&t, 1, 1, try std.time.Instant.now()));
+    _ = try gesture.press(&t, testPress(&t, 1, 1, null));
+
+    try testing.expectEqual(@as(u3, 1), gesture.left_click_count);
+    try testing.expectEqual(@as(?std.time.Instant, null), gesture.left_click_time);
+}
+
+test "SelectionGesture distant press resets click count" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 5, .rows = 5 });
+    defer t.deinit(testing.allocator);
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    const time = try std.time.Instant.now();
+    _ = try gesture.press(&t, testPress(&t, 1, 1, time));
+    _ = try gesture.press(&t, testPress(&t, 4, 1, time));
+
+    try testing.expectEqual(@as(u3, 1), gesture.left_click_count);
+    try testing.expectEqual(@as(f64, 4), gesture.left_click_xpos);
+}
+
+test "SelectionGesture expired repeat resets click count" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 5, .rows = 5 });
+    defer t.deinit(testing.allocator);
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    var event = testPress(&t, 1, 1, try std.time.Instant.now());
+    event.repeat_interval = 0;
+    _ = try gesture.press(&t, event);
+
+    std.Thread.sleep(std.time.ns_per_ms);
+    event.time = try std.time.Instant.now();
+    _ = try gesture.press(&t, event);
+
+    try testing.expectEqual(@as(u3, 1), gesture.left_click_count);
+}
+
+test "SelectionGesture screen switch resets click count" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 5, .rows = 5 });
+    defer t.deinit(testing.allocator);
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    const time = try std.time.Instant.now();
+    const primary_tracked = t.screens.active.pages.countTrackedPins();
+    _ = try gesture.press(&t, testPress(&t, 1, 1, time));
+
+    _ = try t.screens.getInit(testing.allocator, .alternate, .{
+        .cols = t.cols,
+        .rows = t.rows,
+    });
+    t.screens.switchTo(.alternate);
+    _ = try gesture.press(&t, testPress(&t, 1, 1, time));
+
+    try testing.expectEqual(@as(u3, 1), gesture.left_click_count);
+    try testing.expectEqual(.alternate, gesture.left_click_screen);
+    try testing.expectEqual(primary_tracked, t.screens.get(.primary).?.pages.countTrackedPins());
+}
+
+test "SelectionGesture removed screen resets without untracking stale pin" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 5, .rows = 5 });
+    defer t.deinit(testing.allocator);
+
+    var gesture: SelectionGesture = .init;
+    defer gesture.deinit(&t);
+
+    _ = try t.screens.getInit(testing.allocator, .alternate, .{
+        .cols = t.cols,
+        .rows = t.rows,
+    });
+    t.screens.switchTo(.alternate);
+    _ = try gesture.press(&t, testPress(&t, 1, 1, try std.time.Instant.now()));
+
+    t.screens.switchTo(.primary);
+    t.screens.remove(testing.allocator, .alternate);
+    _ = try gesture.press(&t, testPress(&t, 1, 1, try std.time.Instant.now()));
+
+    try testing.expectEqual(@as(u3, 1), gesture.left_click_count);
+    try testing.expectEqual(.primary, gesture.left_click_screen);
+}
+
+test "SelectionGesture deinit untracks pin" {
+    var t = try Terminal.init(testing.allocator, .{ .cols = 5, .rows = 5 });
+    defer t.deinit(testing.allocator);
+
+    var gesture: SelectionGesture = .init;
+    const tracked = t.screens.active.pages.countTrackedPins();
+    _ = try gesture.press(&t, testPress(&t, 1, 1, try std.time.Instant.now()));
+    try testing.expectEqual(tracked + 1, t.screens.active.pages.countTrackedPins());
+
+    gesture.deinit(&t);
+    try testing.expectEqual(tracked, t.screens.active.pages.countTrackedPins());
+}
diff --git a/vendor/libghostty-vt/src/terminal/Terminal.zig b/vendor/libghostty-vt/src/terminal/Terminal.zig
index 6740a93e..d41e4750 100644
--- a/vendor/libghostty-vt/src/terminal/Terminal.zig
+++ b/vendor/libghostty-vt/src/terminal/Terminal.zig
@@ -377,20 +377,20 @@ pub fn print(self: *Terminal, c: u21) !void {
         // necessarily a grapheme break.
         if (prev.cell.codepoint() == 0) break :grapheme;
 
+        var previous_codepoint: u21 = prev.cell.content.codepoint;
         const grapheme_break = brk: {
             var state: uucode.grapheme.BreakState = .default;
-            var cp1: u21 = prev.cell.content.codepoint;
             if (prev.cell.hasGrapheme()) {
                 const cps = self.screens.active.cursor.page_pin.node.data.lookupGrapheme(prev.cell).?;
                 for (cps) |cp2| {
-                    // log.debug("cp1={x} cp2={x}", .{ cp1, cp2 });
-                    assert(!unicode.graphemeBreak(cp1, cp2, &state));
-                    cp1 = cp2;
+                    // log.debug("cp1={x} cp2={x}", .{ previous_codepoint, cp2 });
+                    assert(!unicode.graphemeBreak(previous_codepoint, cp2, &state));
+                    previous_codepoint = cp2;
                 }
             }
 
-            // log.debug("cp1={x} cp2={x} end", .{ cp1, c });
-            break :brk unicode.graphemeBreak(cp1, c, &state);
+            // log.debug("cp1={x} cp2={x} end", .{ previous_codepoint, c });
+            break :brk unicode.graphemeBreak(previous_codepoint, c, &state);
         };
 
         // If we can NOT break, this means that "c" is part of a grapheme
@@ -402,7 +402,7 @@ pub fn print(self: *Terminal, c: u21) !void {
             // the cell width accordingly. VS16 makes the character wide and
             // VS15 makes it narrow.
             if (c == 0xFE0F or c == 0xFE0E) {
-                const prev_props = unicode.table.get(prev.cell.content.codepoint);
+                const prev_props = unicode.table.get(previous_codepoint);
                 // Check if it is a valid variation sequence in
                 // emoji-variation-sequences.txt, and if not, ignore the char.
                 if (!prev_props.emoji_vs_base) return;
@@ -3318,7 +3318,7 @@ test "Terminal: zero-width character at start" {
     try testing.expect(!t.isDirty(.{ .screen = .{ .x = 0, .y = 0 } }));
 }
 
-// https://github.com/ghostty-org/ghostty/issues/12581
+// https://github.com/ghostty-org/ghostty/pull/12581
 test "Terminal: zero-width character attaches to pending wrap cell" {
     var t = try init(testing.allocator, .{ .cols = 2, .rows = 2 });
     defer t.deinit(testing.allocator);
@@ -3741,6 +3741,27 @@ test "Terminal: invalid VS16 doesn't mark dirty" {
     try testing.expect(!t.isDirty(.{ .screen = .{ .x = 0, .y = 0 } }));
 }
 
+// https://github.com/ghostty-org/ghostty/pull/12596
+test "Terminal: variation selectors apply to preceding codepoint" {
+    var t = try init(testing.allocator, .{ .cols = 5, .rows = 5 });
+    defer t.deinit(testing.allocator);
+
+    // Enable grapheme clustering
+    t.modes.set(.grapheme_cluster, true);
+
+    // Pirate flag: black flag + ZWJ + skull and crossbones + VS16.
+    try t.print(0x1F3F4);
+    try t.print(0x200D);
+    try t.print(0x2620);
+    try t.print(0xFE0F);
+
+    const list_cell = t.screens.active.pages.getCell(.{ .screen = .{ .x = 0, .y = 0 } }).?;
+    const cell = list_cell.cell;
+    try testing.expectEqual(@as(u21, 0x1F3F4), cell.content.codepoint);
+    try testing.expect(cell.hasGrapheme());
+    try testing.expectEqualSlices(u21, &.{ 0x200D, 0x2620, 0xFE0F }, list_cell.node.data.lookupGrapheme(cell).?);
+}
+
 test "Terminal: print multicodepoint grapheme, mode 2027" {
     var t = try init(testing.allocator, .{ .cols = 80, .rows = 80 });
     defer t.deinit(testing.allocator);
diff --git a/vendor/libghostty-vt/src/terminal/c/grid_ref_tracked.zig b/vendor/libghostty-vt/src/terminal/c/grid_ref_tracked.zig
new file mode 100644
index 00000000..60091715
--- /dev/null
+++ b/vendor/libghostty-vt/src/terminal/c/grid_ref_tracked.zig
@@ -0,0 +1,225 @@
+const std = @import("std");
+const testing = std.testing;
+const lib = @import("../lib.zig");
+const PageList = @import("../PageList.zig");
+const point = @import("../point.zig");
+const grid_ref_c = @import("grid_ref.zig");
+const terminal_c = @import("terminal.zig");
+const Result = @import("result.zig").Result;
+
+/// C: GhosttyTrackedGridRef
+///
+/// An owned tracked reference to a position in the terminal grid. The
+/// underlying PageList pin is automatically updated as the PageList changes.
+pub const CTrackedGridRef = ?*TrackedGridRef;
+
+pub const TrackedGridRef = struct {
+    alloc: std.mem.Allocator,
+    terminal: terminal_c.Terminal,
+    screen_key: terminal_c.TerminalScreen,
+    screen_generation: usize,
+    pin: *PageList.Pin,
+
+    /// Return the PageList that owns this tracked ref's pin, or null if the
+    /// owning screen has been removed/reinitialized since the ref was created.
+    fn pageList(ref: *const TrackedGridRef) ?*PageList {
+        const wrapper = ref.terminal orelse return null;
+        const t = wrapper.terminal;
+        if (t.screens.generation(ref.screen_key) != ref.screen_generation) return null;
+        const screen = t.screens.get(ref.screen_key) orelse return null;
+        return &screen.pages;
+    }
+};
+
+pub fn tracked_grid_ref_free(ref_: CTrackedGridRef) callconv(lib.calling_conv) void {
+    const ref = ref_ orelse return;
+    if (ref.terminal) |wrapper| {
+        _ = wrapper.tracked_grid_refs.swapRemove(ref);
+    }
+    if (ref.pageList()) |list| list.untrackPin(ref.pin);
+    ref.alloc.destroy(ref);
+}
+
+pub fn tracked_grid_ref_has_value(ref_: CTrackedGridRef) callconv(lib.calling_conv) bool {
+    const ref = ref_ orelse return false;
+    _ = ref.pageList() orelse return false;
+    return !ref.pin.garbage;
+}
+
+pub fn tracked_grid_ref_snapshot(
+    ref_: CTrackedGridRef,
+    out_ref: ?*grid_ref_c.CGridRef,
+) callconv(lib.calling_conv) Result {
+    const ref = ref_ orelse return .invalid_value;
+    _ = ref.pageList() orelse return .no_value;
+    if (ref.pin.garbage) return .no_value;
+    if (out_ref) |out| out.* = grid_ref_c.CGridRef.fromPin(ref.pin.*);
+    return .success;
+}
+
+pub fn tracked_grid_ref_point(
+    ref_: CTrackedGridRef,
+    tag: point.Tag,
+    out: ?*point.Coordinate,
+) callconv(lib.calling_conv) Result {
+    const ref = ref_ orelse return .invalid_value;
+    const list = ref.pageList() orelse return .no_value;
+    if (ref.pin.garbage) return .no_value;
+    const pt = list.pointFromPin(tag, ref.pin.*) orelse return .no_value;
+    if (out) |o| o.* = pt.coord();
+    return .success;
+}
+
+pub fn tracked_grid_ref_set(
+    ref_: CTrackedGridRef,
+    terminal_: terminal_c.Terminal,
+    pt: point.Point.C,
+) callconv(lib.calling_conv) Result {
+    const ref = ref_ orelse return .invalid_value;
+    const wrapper = terminal_ orelse return .invalid_value;
+    if (ref.terminal != terminal_) return .invalid_value;
+
+    const t = wrapper.terminal;
+    const list = &t.screens.active.pages;
+    const p = list.pin(point.Point.fromC(pt)) orelse return .invalid_value;
+    const tracked_pin = list.trackPin(p) catch return .out_of_memory;
+
+    if (ref.pageList()) |old_list| old_list.untrackPin(ref.pin);
+    ref.screen_key = t.screens.active_key;
+    ref.screen_generation = t.screens.generation(ref.screen_key);
+    ref.pin = tracked_pin;
+    return .success;
+}
+
+test "tracked_grid_ref snapshots after terminal scroll" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{ .cols = 5, .rows = 2, .max_scrollback = 10_000 },
+    ));
+    defer terminal_c.free(terminal);
+
+    terminal_c.vt_write(terminal, "A", 1);
+
+    var ref: CTrackedGridRef = null;
+    try testing.expectEqual(Result.success, terminal_c.grid_ref_track(
+        terminal,
+        point.Point.cval(.{ .active = .{ .x = 0, .y = 0 } }),
+        &ref,
+    ));
+    defer tracked_grid_ref_free(ref);
+
+    terminal_c.vt_write(terminal, "\r\nB\r\nC", 6);
+    try testing.expect(tracked_grid_ref_has_value(ref));
+
+    var snapshot: grid_ref_c.CGridRef = undefined;
+    try testing.expectEqual(Result.success, tracked_grid_ref_snapshot(ref, &snapshot));
+
+    var buf: [1]u32 = undefined;
+    var len: usize = undefined;
+    try testing.expectEqual(Result.success, grid_ref_c.grid_ref_graphemes(&snapshot, &buf, buf.len, &len));
+    try testing.expectEqual(@as(usize, 1), len);
+    try testing.expectEqual(@as(u32, 'A'), buf[0]);
+}
+
+test "tracked_grid_ref reports no value after reset" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{ .cols = 5, .rows = 2, .max_scrollback = 10_000 },
+    ));
+    defer terminal_c.free(terminal);
+
+    terminal_c.vt_write(terminal, "A", 1);
+
+    var ref: CTrackedGridRef = null;
+    try testing.expectEqual(Result.success, terminal_c.grid_ref_track(
+        terminal,
+        point.Point.cval(.{ .active = .{ .x = 0, .y = 0 } }),
+        &ref,
+    ));
+    defer tracked_grid_ref_free(ref);
+
+    terminal_c.reset(terminal);
+    try testing.expect(!tracked_grid_ref_has_value(ref));
+
+    var snapshot: grid_ref_c.CGridRef = undefined;
+    try testing.expectEqual(Result.no_value, tracked_grid_ref_snapshot(ref, &snapshot));
+}
+
+test "tracked_grid_ref reports no value after alternate screen reset" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{ .cols = 5, .rows = 2, .max_scrollback = 10_000 },
+    ));
+    defer terminal_c.free(terminal);
+
+    terminal_c.vt_write(terminal, "\x1b[?1049hA", 9);
+
+    var ref: CTrackedGridRef = null;
+    try testing.expectEqual(Result.success, terminal_c.grid_ref_track(
+        terminal,
+        point.Point.cval(.{ .active = .{ .x = 0, .y = 0 } }),
+        &ref,
+    ));
+    defer tracked_grid_ref_free(ref);
+
+    terminal_c.vt_write(terminal, "\x1bc", 2);
+    try testing.expect(!tracked_grid_ref_has_value(ref));
+
+    var snapshot: grid_ref_c.CGridRef = undefined;
+    try testing.expectEqual(Result.no_value, tracked_grid_ref_snapshot(ref, &snapshot));
+
+    var coord: point.Coordinate = undefined;
+    try testing.expectEqual(Result.no_value, tracked_grid_ref_point(ref, .active, &coord));
+
+    terminal_c.vt_write(terminal, "\x1b[?1049h", 8);
+    try testing.expect(!tracked_grid_ref_has_value(ref));
+
+    try testing.expectEqual(Result.success, tracked_grid_ref_set(
+        ref,
+        terminal,
+        point.Point.cval(.{ .active = .{ .x = 0, .y = 0 } }),
+    ));
+    try testing.expect(tracked_grid_ref_has_value(ref));
+    try testing.expectEqual(Result.success, tracked_grid_ref_snapshot(ref, &snapshot));
+}
+
+test "tracked_grid_ref reports no value after terminal free" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{ .cols = 5, .rows = 2, .max_scrollback = 10_000 },
+    ));
+
+    terminal_c.vt_write(terminal, "A", 1);
+
+    var ref: CTrackedGridRef = null;
+    try testing.expectEqual(Result.success, terminal_c.grid_ref_track(
+        terminal,
+        point.Point.cval(.{ .active = .{ .x = 0, .y = 0 } }),
+        &ref,
+    ));
+
+    terminal_c.free(terminal);
+    try testing.expect(!tracked_grid_ref_has_value(ref));
+
+    var snapshot: grid_ref_c.CGridRef = undefined;
+    try testing.expectEqual(Result.no_value, tracked_grid_ref_snapshot(ref, &snapshot));
+
+    var coord: point.Coordinate = undefined;
+    try testing.expectEqual(Result.no_value, tracked_grid_ref_point(ref, .active, &coord));
+
+    try testing.expectEqual(Result.invalid_value, tracked_grid_ref_set(
+        ref,
+        terminal,
+        point.Point.cval(.{ .active = .{ .x = 0, .y = 0 } }),
+    ));
+
+    tracked_grid_ref_free(ref);
+}
diff --git a/vendor/libghostty-vt/src/terminal/c/main.zig b/vendor/libghostty-vt/src/terminal/c/main.zig
index 126b6640..648bdbe5 100644
--- a/vendor/libghostty-vt/src/terminal/c/main.zig
+++ b/vendor/libghostty-vt/src/terminal/c/main.zig
@@ -8,6 +8,7 @@ pub const color = @import("color.zig");
 pub const focus = @import("focus.zig");
 pub const formatter = @import("formatter.zig");
 pub const grid_ref = @import("grid_ref.zig");
+pub const grid_ref_tracked = @import("grid_ref_tracked.zig");
 pub const kitty_graphics = @import("kitty_graphics.zig");
 pub const kitty_graphics_get = kitty_graphics.get;
 pub const kitty_graphics_image = kitty_graphics.image_get_handle;
@@ -30,6 +31,7 @@ pub const modes = @import("modes.zig");
 pub const osc = @import("osc.zig");
 pub const render = @import("render.zig");
 pub const selection = @import("selection.zig");
+pub const selection_gesture = @import("selection_gesture.zig");
 pub const key_event = @import("key_event.zig");
 pub const key_encode = @import("key_encode.zig");
 pub const mouse_event = @import("mouse_event.zig");
@@ -169,7 +171,29 @@ pub const terminal_mode_get = terminal.mode_get;
 pub const terminal_mode_set = terminal.mode_set;
 pub const terminal_get = terminal.get;
 pub const terminal_get_multi = terminal.get_multi;
+pub const terminal_select_word = selection.word;
+pub const terminal_select_word_between = selection.word_between;
+pub const terminal_select_line = selection.line;
+pub const terminal_select_all = selection.all;
+pub const terminal_select_output = selection.output;
+pub const terminal_selection_format_buf = selection.format_buf;
+pub const terminal_selection_format_alloc = selection.format_alloc;
+pub const terminal_selection_adjust = selection.adjust;
+pub const terminal_selection_order = selection.order;
+pub const terminal_selection_ordered = selection.ordered;
+pub const terminal_selection_contains = selection.contains;
+pub const terminal_selection_equal = selection.equal;
+pub const selection_gesture_new = selection_gesture.new;
+pub const selection_gesture_free = selection_gesture.free;
+pub const selection_gesture_reset = selection_gesture.reset;
+pub const selection_gesture_event = selection_gesture.handle_event;
+pub const selection_gesture_get = selection_gesture.get;
+pub const selection_gesture_get_multi = selection_gesture.get_multi;
+pub const selection_gesture_event_new = selection_gesture.event_new;
+pub const selection_gesture_event_free = selection_gesture.event_free;
+pub const selection_gesture_event_set = selection_gesture.event_set;
 pub const terminal_grid_ref = terminal.grid_ref;
+pub const terminal_grid_ref_track = terminal.grid_ref_track;
 pub const terminal_point_from_grid_ref = terminal.point_from_grid_ref;
 
 pub const type_json = types.get_json;
@@ -179,6 +203,11 @@ pub const grid_ref_row = grid_ref.grid_ref_row;
 pub const grid_ref_graphemes = grid_ref.grid_ref_graphemes;
 pub const grid_ref_hyperlink_uri = grid_ref.grid_ref_hyperlink_uri;
 pub const grid_ref_style = grid_ref.grid_ref_style;
+pub const tracked_grid_ref_free = grid_ref_tracked.tracked_grid_ref_free;
+pub const tracked_grid_ref_has_value = grid_ref_tracked.tracked_grid_ref_has_value;
+pub const tracked_grid_ref_point = grid_ref_tracked.tracked_grid_ref_point;
+pub const tracked_grid_ref_set = grid_ref_tracked.tracked_grid_ref_set;
+pub const tracked_grid_ref_snapshot = grid_ref_tracked.tracked_grid_ref_snapshot;
 
 test {
     _ = allocator;
@@ -186,6 +215,7 @@ test {
     _ = cell;
     _ = color;
     _ = grid_ref;
+    _ = grid_ref_tracked;
     _ = kitty_graphics;
     _ = row;
     _ = focus;
@@ -194,6 +224,7 @@ test {
     _ = osc;
     _ = render;
     _ = selection;
+    _ = selection_gesture;
     _ = key_event;
     _ = key_encode;
     _ = mouse_event;
diff --git a/vendor/libghostty-vt/src/terminal/c/render.zig b/vendor/libghostty-vt/src/terminal/c/render.zig
index af82ddfa..0f3b2e78 100644
--- a/vendor/libghostty-vt/src/terminal/c/render.zig
+++ b/vendor/libghostty-vt/src/terminal/c/render.zig
@@ -31,6 +31,7 @@ const RowIteratorWrapper = struct {
     /// These are the raw pointers into the render state data.
     raws: []const page.Row,
     cells: []const std.MultiArrayList(renderpkg.RenderState.Cell),
+    selection: []const ?[2]size.CellCountInt,
     dirty: []bool,
 
     /// The color palette from the render state, needed to resolve
@@ -44,6 +45,7 @@ const RowCellsWrapper = struct {
     raws: []const page.Cell,
     graphemes: []const []const u21,
     styles: []const Style,
+    selection: ?[2]size.CellCountInt,
 
     /// The color palette, needed to resolve palette-indexed background colors.
     palette: *const colorpkg.Palette,
@@ -61,6 +63,13 @@ pub const RowCells = ?*RowCellsWrapper;
 /// C: GhosttyRenderStateDirty
 pub const Dirty = renderpkg.RenderState.Dirty;
 
+/// C: GhosttyRenderStateRowSelection
+pub const RowSelection = extern struct {
+    size: usize = @sizeOf(RowSelection),
+    start_x: u16 = 0,
+    end_x: u16 = 0,
+};
+
 /// C: GhosttyRenderStateCursorVisualStyle
 pub const CursorVisualStyle = enum(c_int) {
     bar = 0,
@@ -241,6 +250,7 @@ fn getTyped(
                 .y = null,
                 .raws = row_data.items(.raw),
                 .cells = row_data.items(.cells),
+                .selection = row_data.items(.selection),
                 .dirty = row_data.items(.dirty),
                 .palette = &state.state.colors.palette,
             };
@@ -381,6 +391,7 @@ pub fn row_iterator_new(
         .y = undefined,
         .raws = undefined,
         .cells = undefined,
+        .selection = undefined,
         .dirty = undefined,
         .palette = undefined,
     };
@@ -417,6 +428,7 @@ pub fn row_cells_new(
         .raws = undefined,
         .graphemes = undefined,
         .styles = undefined,
+        .selection = undefined,
         .palette = undefined,
     };
     result.* = ptr;
@@ -453,6 +465,9 @@ pub const RowCellsData = enum(c_int) {
     graphemes_buf = 4,
     bg_color = 5,
     fg_color = 6,
+    selected = 7,
+    has_styling = 8,
+    graphemes_utf8 = 9,
 
     /// Output type expected for querying the data of the given kind.
     pub fn OutType(comptime self: RowCellsData) type {
@@ -463,6 +478,8 @@ pub const RowCellsData = enum(c_int) {
             .graphemes_len => u32,
             .graphemes_buf => u32,
             .bg_color, .fg_color => colorpkg.RGB.C,
+            .selected, .has_styling => bool,
+            .graphemes_utf8 => lib.Buffer,
         };
     }
 };
@@ -478,6 +495,7 @@ pub fn row_cells_get(
             return .invalid_value;
         };
     }
+    if (out == null) return .invalid_value;
 
     return switch (data) {
         .invalid => .invalid_value,
@@ -553,17 +571,56 @@ fn rowCellsGetTyped(
             const fg = s.fg(.{ .default = .{}, .palette = cells.palette });
             out.* = fg.cval();
         },
+        .selected => out.* = if (cells.selection) |sel|
+            x >= sel[0] and x <= sel[1]
+        else
+            false,
+        .has_styling => out.* = cell.hasStyling(),
+        .graphemes_utf8 => return rowCellsGetGraphemesUtf8(cell, if (cell.hasGrapheme()) cells.graphemes[x] else &.{}, out),
     }
 
     return .success;
 }
 
+fn rowCellsGetGraphemesUtf8(
+    cell: page.Cell,
+    extra: []const u21,
+    out: *lib.Buffer,
+) Result {
+    out.len = 0;
+
+    if (!cell.hasText()) return .success;
+
+    var needed = std.unicode.utf8CodepointSequenceLength(cell.codepoint()) catch
+        return .invalid_value;
+    for (extra) |cp| {
+        needed += std.unicode.utf8CodepointSequenceLength(cp) catch
+            return .invalid_value;
+    }
+    out.len = needed;
+
+    if (out.ptr == null or out.cap < needed) return .out_of_space;
+
+    const buf = out.ptr.?[0..out.cap];
+    var i: usize = 0;
+    i += std.unicode.utf8Encode(cell.codepoint(), buf[i..]) catch
+        return .invalid_value;
+    for (extra) |cp| {
+        i += std.unicode.utf8Encode(cp, buf[i..]) catch
+            return .invalid_value;
+    }
+
+    out.len = i;
+    return .success;
+}
+
 /// C: GhosttyRenderStateRowData
 pub const RowData = enum(c_int) {
     invalid = 0,
     dirty = 1,
     raw = 2,
     cells = 3,
+    selection = 4,
 
     /// Output type expected for querying the data of the given kind.
     pub fn OutType(comptime self: RowData) type {
@@ -572,6 +629,7 @@ pub const RowData = enum(c_int) {
             .dirty => bool,
             .raw => row.CRow,
             .cells => RowCells,
+            .selection => RowSelection,
         };
     }
 };
@@ -651,9 +709,18 @@ fn rowGetTyped(
                 .raws = cell_data.items(.raw),
                 .graphemes = cell_data.items(.grapheme),
                 .styles = cell_data.items(.style),
+                .selection = it.selection[y],
                 .palette = it.palette,
             };
         },
+        .selection => {
+            const out_size = out.size;
+            if (out_size < @sizeOf(RowSelection)) return .invalid_value;
+
+            const sel = it.selection[y] orelse return .no_value;
+            out.start_x = sel[0];
+            out.end_x = sel[1];
+        },
     }
 
     return .success;
@@ -845,6 +912,7 @@ test "render: row iterator new/free" {
     try testing.expectEqual(@as(?size.CellCountInt, null), iterator_ptr.y);
     try testing.expectEqual(row_data.items(.raw).len, iterator_ptr.raws.len);
     try testing.expectEqual(row_data.items(.cells).len, iterator_ptr.cells.len);
+    try testing.expectEqual(row_data.items(.selection).len, iterator_ptr.selection.len);
     try testing.expectEqual(row_data.items(.dirty).len, iterator_ptr.dirty.len);
 }
 
@@ -1026,6 +1094,267 @@ test "render: row get/set dirty" {
     try testing.expect(!dirty);
 }
 
+test "render: row get selection" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{
+            .cols = 10,
+            .rows = 3,
+            .max_scrollback = 10_000,
+        },
+    ));
+    defer terminal_c.free(terminal);
+
+    const t = terminal.?.terminal;
+    const screen = t.screens.active;
+    try screen.select(.init(
+        screen.pages.pin(.{ .active = .{ .x = 2, .y = 1 } }).?,
+        screen.pages.pin(.{ .active = .{ .x = 4, .y = 1 } }).?,
+        false,
+    ));
+
+    var state: RenderState = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &state,
+    ));
+    defer free(state);
+
+    try testing.expectEqual(Result.success, update(state, terminal));
+
+    var it: RowIterator = null;
+    try testing.expectEqual(Result.success, row_iterator_new(
+        &lib.alloc.test_allocator,
+        &it,
+    ));
+    defer row_iterator_free(it);
+
+    try testing.expectEqual(Result.success, get(state, .row_iterator, @ptrCast(&it)));
+
+    var sel: RowSelection = .{};
+    try testing.expect(row_iterator_next(it));
+    try testing.expectEqual(Result.no_value, row_get(it, .selection, @ptrCast(&sel)));
+
+    try testing.expect(row_iterator_next(it));
+    sel = .{};
+    try testing.expectEqual(Result.success, row_get(it, .selection, @ptrCast(&sel)));
+    try testing.expectEqual(@as(u16, 2), sel.start_x);
+    try testing.expectEqual(@as(u16, 4), sel.end_x);
+
+    try testing.expect(row_iterator_next(it));
+    sel = .{};
+    try testing.expectEqual(Result.no_value, row_get(it, .selection, @ptrCast(&sel)));
+}
+
+test "render: row cells get selected" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{
+            .cols = 10,
+            .rows = 3,
+            .max_scrollback = 10_000,
+        },
+    ));
+    defer terminal_c.free(terminal);
+
+    const t = terminal.?.terminal;
+    const screen = t.screens.active;
+    try screen.select(.init(
+        screen.pages.pin(.{ .active = .{ .x = 2, .y = 1 } }).?,
+        screen.pages.pin(.{ .active = .{ .x = 4, .y = 1 } }).?,
+        false,
+    ));
+
+    var state: RenderState = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &state,
+    ));
+    defer free(state);
+
+    try testing.expectEqual(Result.success, update(state, terminal));
+
+    var it: RowIterator = null;
+    try testing.expectEqual(Result.success, row_iterator_new(
+        &lib.alloc.test_allocator,
+        &it,
+    ));
+    defer row_iterator_free(it);
+
+    var cells: RowCells = null;
+    try testing.expectEqual(Result.success, row_cells_new(
+        &lib.alloc.test_allocator,
+        &cells,
+    ));
+    defer row_cells_free(cells);
+
+    try testing.expectEqual(Result.success, get(state, .row_iterator, @ptrCast(&it)));
+
+    try testing.expect(row_iterator_next(it));
+    try testing.expectEqual(Result.success, row_get(it, .cells, @ptrCast(&cells)));
+
+    var selected: bool = true;
+    try testing.expectEqual(Result.success, row_cells_select(cells, 0));
+    try testing.expectEqual(Result.success, row_cells_get(cells, .selected, @ptrCast(&selected)));
+    try testing.expect(!selected);
+
+    try testing.expect(row_iterator_next(it));
+    try testing.expectEqual(Result.success, row_get(it, .cells, @ptrCast(&cells)));
+
+    try testing.expectEqual(Result.success, row_cells_select(cells, 1));
+    try testing.expectEqual(Result.success, row_cells_get(cells, .selected, @ptrCast(&selected)));
+    try testing.expect(!selected);
+
+    try testing.expectEqual(Result.success, row_cells_select(cells, 2));
+    try testing.expectEqual(Result.success, row_cells_get(cells, .selected, @ptrCast(&selected)));
+    try testing.expect(selected);
+
+    try testing.expectEqual(Result.success, row_cells_select(cells, 4));
+    try testing.expectEqual(Result.success, row_cells_get(cells, .selected, @ptrCast(&selected)));
+    try testing.expect(selected);
+
+    try testing.expectEqual(Result.success, row_cells_select(cells, 5));
+    try testing.expectEqual(Result.success, row_cells_get(cells, .selected, @ptrCast(&selected)));
+    try testing.expect(!selected);
+
+    try testing.expectEqual(Result.success, row_cells_select(cells, 3));
+    selected = false;
+    var written: usize = 0;
+    const keys = [_]RowCellsData{.selected};
+    var values = [_]?*anyopaque{@ptrCast(&selected)};
+    try testing.expectEqual(Result.success, row_cells_get_multi(cells, keys.len, &keys, &values, &written));
+    try testing.expectEqual(keys.len, written);
+    try testing.expect(selected);
+}
+
+test "render: row cells get has_styling" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{
+            .cols = 10,
+            .rows = 3,
+            .max_scrollback = 10_000,
+        },
+    ));
+    defer terminal_c.free(terminal);
+
+    const input = "A\x1b[31mB";
+    terminal_c.vt_write(terminal, input, input.len);
+
+    var state: RenderState = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &state,
+    ));
+    defer free(state);
+
+    try testing.expectEqual(Result.success, update(state, terminal));
+
+    var it: RowIterator = null;
+    try testing.expectEqual(Result.success, row_iterator_new(
+        &lib.alloc.test_allocator,
+        &it,
+    ));
+    defer row_iterator_free(it);
+
+    var cells: RowCells = null;
+    try testing.expectEqual(Result.success, row_cells_new(
+        &lib.alloc.test_allocator,
+        &cells,
+    ));
+    defer row_cells_free(cells);
+
+    try testing.expectEqual(Result.success, get(state, .row_iterator, @ptrCast(&it)));
+    try testing.expect(row_iterator_next(it));
+    try testing.expectEqual(Result.success, row_get(it, .cells, @ptrCast(&cells)));
+
+    var has_styling = true;
+    try testing.expectEqual(Result.success, row_cells_select(cells, 0));
+    try testing.expectEqual(Result.success, row_cells_get(cells, .has_styling, @ptrCast(&has_styling)));
+    try testing.expect(!has_styling);
+
+    try testing.expectEqual(Result.success, row_cells_select(cells, 1));
+    try testing.expectEqual(Result.success, row_cells_get(cells, .has_styling, @ptrCast(&has_styling)));
+    try testing.expect(has_styling);
+
+    has_styling = false;
+    var written: usize = 0;
+    const keys = [_]RowCellsData{.has_styling};
+    var values = [_]?*anyopaque{@ptrCast(&has_styling)};
+    try testing.expectEqual(Result.success, row_cells_get_multi(cells, keys.len, &keys, &values, &written));
+    try testing.expectEqual(keys.len, written);
+    try testing.expect(has_styling);
+}
+
+test "render: row cells get graphemes utf8" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{ .cols = 10, .rows = 3, .max_scrollback = 10_000 },
+    ));
+    defer terminal_c.free(terminal);
+
+    const input = "e\u{301}";
+    terminal_c.vt_write(terminal, input, input.len);
+
+    var state: RenderState = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &state,
+    ));
+    defer free(state);
+
+    try testing.expectEqual(Result.success, update(state, terminal));
+
+    var it: RowIterator = null;
+    try testing.expectEqual(Result.success, row_iterator_new(
+        &lib.alloc.test_allocator,
+        &it,
+    ));
+    defer row_iterator_free(it);
+
+    var cells: RowCells = null;
+    try testing.expectEqual(Result.success, row_cells_new(
+        &lib.alloc.test_allocator,
+        &cells,
+    ));
+    defer row_cells_free(cells);
+
+    try testing.expectEqual(Result.success, get(state, .row_iterator, @ptrCast(&it)));
+    try testing.expect(row_iterator_next(it));
+    try testing.expectEqual(Result.success, row_get(it, .cells, @ptrCast(&cells)));
+
+    try testing.expectEqual(Result.success, row_cells_select(cells, 0));
+
+    var text: lib.Buffer = .{};
+    try testing.expectEqual(Result.out_of_space, row_cells_get(cells, .graphemes_utf8, @ptrCast(&text)));
+    try testing.expectEqual(@as(usize, input.len), text.len);
+
+    var small = [_]u8{ 'x', 'x' };
+    text = .{ .ptr = &small, .cap = small.len };
+    try testing.expectEqual(Result.out_of_space, row_cells_get(cells, .graphemes_utf8, @ptrCast(&text)));
+    try testing.expectEqual(@as(usize, input.len), text.len);
+    try testing.expectEqualSlices(u8, &.{ 'x', 'x' }, &small);
+
+    var buf: [8]u8 = undefined;
+    text = .{ .ptr = &buf, .cap = buf.len };
+    try testing.expectEqual(Result.success, row_cells_get(cells, .graphemes_utf8, @ptrCast(&text)));
+    try testing.expectEqual(input.len, text.len);
+    try testing.expectEqualStrings(input, buf[0..text.len]);
+
+    try testing.expectEqual(Result.success, row_cells_select(cells, 1));
+    text = .{ .ptr = &buf, .cap = buf.len };
+    try testing.expectEqual(Result.success, row_cells_get(cells, .graphemes_utf8, @ptrCast(&text)));
+    try testing.expectEqual(@as(usize, 0), text.len);
+}
+
 test "render: row iterator next" {
     var terminal: terminal_c.Terminal = null;
     try testing.expectEqual(Result.success, terminal_c.new(
diff --git a/vendor/libghostty-vt/src/terminal/c/selection.zig b/vendor/libghostty-vt/src/terminal/c/selection.zig
index 74e96598..cb574ecc 100644
--- a/vendor/libghostty-vt/src/terminal/c/selection.zig
+++ b/vendor/libghostty-vt/src/terminal/c/selection.zig
@@ -1,5 +1,20 @@
+const std = @import("std");
+const testing = std.testing;
+const lib = @import("../lib.zig");
+const CAllocator = lib.alloc.Allocator;
+const formatterpkg = @import("../formatter.zig");
 const grid_ref = @import("grid_ref.zig");
+const point = @import("../point.zig");
+const selection_codepoints = @import("../selection_codepoints.zig");
 const Selection = @import("../Selection.zig");
+const Result = @import("result.zig").Result;
+const terminal_c = @import("terminal.zig");
+
+const log = std.log.scoped(.selection_c);
+
+pub const Adjustment = Selection.Adjustment;
+pub const Order = Selection.Order;
+pub const Format = formatterpkg.Format;
 
 /// C: GhosttySelection
 pub const CSelection = extern struct {
@@ -13,4 +28,504 @@ pub const CSelection = extern struct {
         const end_pin = self.end.toPin() orelse return null;
         return Selection.init(start_pin, end_pin, self.rectangle);
     }
+
+    pub fn fromZig(sel: Selection) CSelection {
+        return .{
+            .start = .fromPin(sel.start()),
+            .end = .fromPin(sel.end()),
+            .rectangle = sel.rectangle,
+        };
+    }
+};
+
+/// C: GhosttyTerminalSelectWordOptions
+pub const SelectWordOptions = extern struct {
+    size: usize = @sizeOf(SelectWordOptions),
+    ref: grid_ref.CGridRef,
+    boundary_codepoints: ?[*]const u32 = null,
+    boundary_codepoints_len: usize = 0,
+};
+
+/// C: GhosttyTerminalSelectWordBetweenOptions
+pub const SelectWordBetweenOptions = extern struct {
+    size: usize = @sizeOf(SelectWordBetweenOptions),
+    start: grid_ref.CGridRef,
+    end: grid_ref.CGridRef,
+    boundary_codepoints: ?[*]const u32 = null,
+    boundary_codepoints_len: usize = 0,
 };
+
+/// C: GhosttyTerminalSelectLineOptions
+pub const SelectLineOptions = extern struct {
+    size: usize = @sizeOf(SelectLineOptions),
+    ref: grid_ref.CGridRef,
+    whitespace: ?[*]const u32 = null,
+    whitespace_len: usize = 0,
+    semantic_prompt_boundary: bool = false,
+};
+
+/// C: GhosttyTerminalSelectionFormatOptions
+pub const FormatOptions = extern struct {
+    size: usize = @sizeOf(FormatOptions),
+    emit: Format,
+    unwrap: bool,
+    trim: bool,
+    selection: ?*const CSelection = null,
+};
+
+pub fn word(
+    terminal: terminal_c.Terminal,
+    options: ?*const SelectWordOptions,
+    out_selection: ?*CSelection,
+) callconv(lib.calling_conv) Result {
+    const t = terminal_c.zigTerminal(terminal) orelse return .invalid_value;
+    const opts = options orelse return .invalid_value;
+    if (opts.size < @sizeOf(SelectWordOptions)) return .invalid_value;
+    const out = out_selection orelse return .invalid_value;
+
+    const boundary_codepoints = codepointSlice(
+        opts.boundary_codepoints,
+        opts.boundary_codepoints_len,
+    ) catch return .invalid_value;
+
+    const screen = t.screens.active;
+    const pin = opts.ref.toPin() orelse return .invalid_value;
+    out.* = .fromZig(screen.selectWord(
+        pin,
+        boundary_codepoints orelse &selection_codepoints.default_word_boundaries,
+    ) orelse
+        return .no_value);
+    return .success;
+}
+
+pub fn word_between(
+    terminal: terminal_c.Terminal,
+    options: ?*const SelectWordBetweenOptions,
+    out_selection: ?*CSelection,
+) callconv(lib.calling_conv) Result {
+    const t = terminal_c.zigTerminal(terminal) orelse return .invalid_value;
+    const opts = options orelse return .invalid_value;
+    if (opts.size < @sizeOf(SelectWordBetweenOptions)) return .invalid_value;
+    const out = out_selection orelse return .invalid_value;
+
+    const boundary_codepoints = codepointSlice(
+        opts.boundary_codepoints,
+        opts.boundary_codepoints_len,
+    ) catch return .invalid_value;
+
+    const screen = t.screens.active;
+    const start = opts.start.toPin() orelse return .invalid_value;
+    const end = opts.end.toPin() orelse return .invalid_value;
+    out.* = .fromZig(screen.selectWordBetween(
+        start,
+        end,
+        boundary_codepoints orelse &selection_codepoints.default_word_boundaries,
+    ) orelse
+        return .no_value);
+    return .success;
+}
+
+pub fn line(
+    terminal: terminal_c.Terminal,
+    options: ?*const SelectLineOptions,
+    out_selection: ?*CSelection,
+) callconv(lib.calling_conv) Result {
+    const t = terminal_c.zigTerminal(terminal) orelse return .invalid_value;
+    const opts = options orelse return .invalid_value;
+    if (opts.size < @sizeOf(SelectLineOptions)) return .invalid_value;
+    const out = out_selection orelse return .invalid_value;
+
+    const whitespace = codepointSlice(
+        opts.whitespace,
+        opts.whitespace_len,
+    ) catch return .invalid_value;
+
+    const screen = t.screens.active;
+    const pin = opts.ref.toPin() orelse return .invalid_value;
+    out.* = .fromZig(screen.selectLine(.{
+        .pin = pin,
+        .whitespace = whitespace orelse &selection_codepoints.default_line_whitespace,
+        .semantic_prompt_boundary = opts.semantic_prompt_boundary,
+    }) orelse return .no_value);
+    return .success;
+}
+
+pub fn all(
+    terminal: terminal_c.Terminal,
+    out_selection: ?*CSelection,
+) callconv(lib.calling_conv) Result {
+    const t = terminal_c.zigTerminal(terminal) orelse return .invalid_value;
+    const out = out_selection orelse return .invalid_value;
+
+    out.* = .fromZig(t.screens.active.selectAll() orelse return .no_value);
+    return .success;
+}
+
+pub fn output(
+    terminal: terminal_c.Terminal,
+    ref: grid_ref.CGridRef,
+    out_selection: ?*CSelection,
+) callconv(lib.calling_conv) Result {
+    const t = terminal_c.zigTerminal(terminal) orelse return .invalid_value;
+    const out = out_selection orelse return .invalid_value;
+
+    const screen = t.screens.active;
+    const pin = ref.toPin() orelse return .invalid_value;
+    out.* = .fromZig(screen.selectOutput(pin) orelse return .no_value);
+    return .success;
+}
+
+pub fn format_buf(
+    terminal: terminal_c.Terminal,
+    opts: FormatOptions,
+    out_: ?[*]u8,
+    out_len: usize,
+    out_written: *usize,
+) callconv(lib.calling_conv) Result {
+    const t = terminal_c.zigTerminal(terminal) orelse return .invalid_value;
+
+    if (out_ == null) {
+        var discarding: std.Io.Writer.Discarding = .init(&.{});
+        formatSelection(t, opts, &discarding.writer) catch |err| return switch (err) {
+            error.InvalidValue => .invalid_value,
+            error.NoValue => .no_value,
+            error.WriteFailed => unreachable,
+        };
+        out_written.* = @intCast(discarding.count);
+        return .out_of_space;
+    }
+
+    var writer: std.Io.Writer = .fixed(out_.?[0..out_len]);
+    formatSelection(t, opts, &writer) catch |err| switch (err) {
+        error.InvalidValue => return .invalid_value,
+        error.NoValue => return .no_value,
+        error.WriteFailed => {
+            var discarding: std.Io.Writer.Discarding = .init(&.{});
+            formatSelection(t, opts, &discarding.writer) catch unreachable;
+            out_written.* = @intCast(discarding.count);
+            return .out_of_space;
+        },
+    };
+
+    out_written.* = writer.end;
+    return .success;
+}
+
+pub fn format_alloc(
+    terminal: terminal_c.Terminal,
+    alloc_: ?*const CAllocator,
+    opts: FormatOptions,
+    out_ptr: *?[*]u8,
+    out_len: *usize,
+) callconv(lib.calling_conv) Result {
+    out_ptr.* = null;
+    out_len.* = 0;
+
+    const t = terminal_c.zigTerminal(terminal) orelse return .invalid_value;
+    const alloc = lib.alloc.default(alloc_);
+
+    var aw: std.Io.Writer.Allocating = .init(alloc);
+    defer aw.deinit();
+
+    formatSelection(t, opts, &aw.writer) catch |err| return switch (err) {
+        error.InvalidValue => .invalid_value,
+        error.NoValue => .no_value,
+        error.WriteFailed => .out_of_memory,
+    };
+
+    const buf = aw.toOwnedSlice() catch return .out_of_memory;
+    out_ptr.* = buf.ptr;
+    out_len.* = buf.len;
+    return .success;
+}
+
+fn formatSelection(
+    t: *terminal_c.ZigTerminal,
+    opts: FormatOptions,
+    writer: *std.Io.Writer,
+) error{ InvalidValue, NoValue, WriteFailed }!void {
+    var formatter = selectionFormatter(t, opts) catch |err| return err;
+    try formatter.format(writer);
+}
+
+fn selectionFormatter(
+    t: *terminal_c.ZigTerminal,
+    opts: FormatOptions,
+) error{ InvalidValue, NoValue }!formatterpkg.TerminalFormatter {
+    if (opts.size < @sizeOf(FormatOptions)) return error.InvalidValue;
+    _ = std.meta.intToEnum(Format, @intFromEnum(opts.emit)) catch
+        return error.InvalidValue;
+
+    const sel = if (opts.selection) |sel|
+        sel.toZig() orelse return error.InvalidValue
+    else
+        t.screens.active.selection orelse return error.NoValue;
+
+    var formatter: formatterpkg.TerminalFormatter = .init(t, .{
+        .emit = opts.emit,
+        .unwrap = opts.unwrap,
+        .trim = opts.trim,
+    });
+    formatter.content = .{ .selection = sel };
+    return formatter;
+}
+
+/// Return the borrowed C array of `uint32_t` codepoints as a `[]const u21`.
+///
+/// `NULL + len 0` returns null, which callers treat as “use the API default
+/// set.” A non-null pointer with `len 0` returns an empty slice, meaning “use an
+/// explicitly empty set.” A non-zero length requires a non-null pointer.
+///
+/// This is intentionally zero-copy. In the C ABI, codepoints are `uint32_t`,
+/// but selection internals use Zig's `u21` to represent valid Unicode scalar
+/// values. Zig currently stores `u21` in the same size and alignment as `u32`,
+/// so we assert that layout relationship and reinterpret the borrowed slice.
+/// If Zig ever changes that representation, these comptime assertions fail
+/// loudly rather than silently making this cast wrong.
+fn codepointSlice(
+    ptr: ?[*]const u32,
+    len: usize,
+) error{InvalidValue}!?[]const u21 {
+    comptime {
+        std.debug.assert(@sizeOf(u21) == @sizeOf(u32));
+        std.debug.assert(@alignOf(u21) == @alignOf(u32));
+    }
+
+    if (len == 0) {
+        const p = ptr orelse return null;
+        _ = p;
+        return &.{};
+    }
+
+    const p = ptr orelse return error.InvalidValue;
+    const cps: [*]const u21 = @ptrCast(p);
+    return cps[0..len];
+}
+
+pub fn adjust(
+    terminal: terminal_c.Terminal,
+    selection: ?*CSelection,
+    adjustment: Selection.Adjustment,
+) callconv(lib.calling_conv) Result {
+    if (comptime std.debug.runtime_safety) {
+        _ = std.meta.intToEnum(Selection.Adjustment, @intFromEnum(adjustment)) catch {
+            log.warn("terminal_selection_adjust invalid adjustment value={d}", .{@intFromEnum(adjustment)});
+            return .invalid_value;
+        };
+    }
+
+    const t = terminal_c.zigTerminal(terminal) orelse return .invalid_value;
+    const sel_ptr = selection orelse return .invalid_value;
+    var sel = sel_ptr.toZig() orelse return .invalid_value;
+    sel.adjust(t.screens.active, adjustment);
+    sel_ptr.* = .fromZig(sel);
+    return .success;
+}
+
+pub fn order(
+    terminal: terminal_c.Terminal,
+    selection: ?*const CSelection,
+    out_order: ?*Selection.Order,
+) callconv(lib.calling_conv) Result {
+    const t = terminal_c.zigTerminal(terminal) orelse return .invalid_value;
+    const sel = (selection orelse return .invalid_value).toZig() orelse
+        return .invalid_value;
+    const out = out_order orelse return .invalid_value;
+
+    out.* = sel.order(t.screens.active);
+    return .success;
+}
+
+pub fn ordered(
+    terminal: terminal_c.Terminal,
+    selection: ?*const CSelection,
+    desired: Selection.Order,
+    out_selection: ?*CSelection,
+) callconv(lib.calling_conv) Result {
+    if (comptime std.debug.runtime_safety) {
+        _ = std.meta.intToEnum(Selection.Order, @intFromEnum(desired)) catch {
+            log.warn("terminal_selection_ordered invalid desired value={d}", .{@intFromEnum(desired)});
+            return .invalid_value;
+        };
+    }
+
+    const t = terminal_c.zigTerminal(terminal) orelse return .invalid_value;
+    const sel = (selection orelse return .invalid_value).toZig() orelse
+        return .invalid_value;
+    const out = out_selection orelse return .invalid_value;
+
+    out.* = .fromZig(sel.ordered(t.screens.active, desired));
+    return .success;
+}
+
+pub fn contains(
+    terminal: terminal_c.Terminal,
+    selection: ?*const CSelection,
+    pt: point.Point.C,
+    out_contains: ?*bool,
+) callconv(lib.calling_conv) Result {
+    const t = terminal_c.zigTerminal(terminal) orelse return .invalid_value;
+    const sel = (selection orelse return .invalid_value).toZig() orelse
+        return .invalid_value;
+    const out = out_contains orelse return .invalid_value;
+
+    const screen = t.screens.active;
+    const pin = screen.pages.pin(.fromC(pt)) orelse return .invalid_value;
+    out.* = sel.contains(screen, pin);
+    return .success;
+}
+
+pub fn equal(
+    terminal: terminal_c.Terminal,
+    a: ?*const CSelection,
+    b: ?*const CSelection,
+    out_equal: ?*bool,
+) callconv(lib.calling_conv) Result {
+    _ = terminal_c.zigTerminal(terminal) orelse return .invalid_value;
+    const sel_a = (a orelse return .invalid_value).toZig() orelse
+        return .invalid_value;
+    const sel_b = (b orelse return .invalid_value).toZig() orelse
+        return .invalid_value;
+    const out = out_equal orelse return .invalid_value;
+
+    out.* = sel_a.eql(sel_b);
+    return .success;
+}
+
+test "selection_format_alloc uses active selection" {
+    var t: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &t,
+        .{ .cols = 80, .rows = 24, .max_scrollback = 10_000 },
+    ));
+    defer terminal_c.free(t);
+
+    terminal_c.vt_write(t, "Hello World", 11);
+
+    var start_ref: grid_ref.CGridRef = .{};
+    try testing.expectEqual(Result.success, terminal_c.grid_ref(t, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 6, .y = 0 } },
+    }, &start_ref));
+
+    var end_ref: grid_ref.CGridRef = .{};
+    try testing.expectEqual(Result.success, terminal_c.grid_ref(t, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 10, .y = 0 } },
+    }, &end_ref));
+
+    const sel: CSelection = .{
+        .start = start_ref,
+        .end = end_ref,
+    };
+    try testing.expectEqual(Result.success, terminal_c.set(t, .selection, @ptrCast(&sel)));
+
+    const opts: FormatOptions = .{
+        .emit = .plain,
+        .unwrap = true,
+        .trim = true,
+    };
+
+    var required: usize = 0;
+    try testing.expectEqual(Result.out_of_space, format_buf(
+        t,
+        opts,
+        null,
+        0,
+        &required,
+    ));
+    try testing.expectEqual(@as(usize, 5), required);
+
+    var out_ptr: ?[*]u8 = null;
+    var out_len: usize = 0;
+    try testing.expectEqual(Result.success, format_alloc(
+        t,
+        &lib.alloc.test_allocator,
+        opts,
+        &out_ptr,
+        &out_len,
+    ));
+    const ptr = out_ptr orelse return error.TestExpectedEqual;
+    defer lib.alloc.default(&lib.alloc.test_allocator).free(ptr[0..out_len]);
+
+    try testing.expectEqualStrings("World", ptr[0..out_len]);
+}
+
+test "selection_format_buf uses provided selection" {
+    var t: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &t,
+        .{ .cols = 80, .rows = 24, .max_scrollback = 10_000 },
+    ));
+    defer terminal_c.free(t);
+
+    terminal_c.vt_write(t, "Hello World", 11);
+
+    var start_ref: grid_ref.CGridRef = .{};
+    try testing.expectEqual(Result.success, terminal_c.grid_ref(t, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 0, .y = 0 } },
+    }, &start_ref));
+
+    var end_ref: grid_ref.CGridRef = .{};
+    try testing.expectEqual(Result.success, terminal_c.grid_ref(t, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 4, .y = 0 } },
+    }, &end_ref));
+
+    const sel: CSelection = .{
+        .start = start_ref,
+        .end = end_ref,
+    };
+    const opts: FormatOptions = .{
+        .emit = .plain,
+        .unwrap = true,
+        .trim = true,
+        .selection = &sel,
+    };
+
+    var small: [2]u8 = undefined;
+    var written: usize = 0;
+    try testing.expectEqual(Result.out_of_space, format_buf(
+        t,
+        opts,
+        &small,
+        small.len,
+        &written,
+    ));
+    try testing.expectEqual(@as(usize, 5), written);
+
+    var buf: [32]u8 = undefined;
+    try testing.expectEqual(Result.success, format_buf(
+        t,
+        opts,
+        &buf,
+        buf.len,
+        &written,
+    ));
+    try testing.expectEqualStrings("Hello", buf[0..written]);
+}
+
+test "selection_format_alloc returns no_value without active selection" {
+    var t: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &t,
+        .{ .cols = 80, .rows = 24, .max_scrollback = 10_000 },
+    ));
+    defer terminal_c.free(t);
+
+    var out_ptr: ?[*]u8 = @ptrFromInt(1);
+    var out_len: usize = 123;
+    try testing.expectEqual(Result.no_value, format_alloc(
+        t,
+        &lib.alloc.test_allocator,
+        .{ .emit = .plain, .unwrap = true, .trim = true },
+        &out_ptr,
+        &out_len,
+    ));
+    try testing.expect(out_ptr == null);
+    try testing.expectEqual(@as(usize, 0), out_len);
+}
diff --git a/vendor/libghostty-vt/src/terminal/c/selection_gesture.zig b/vendor/libghostty-vt/src/terminal/c/selection_gesture.zig
new file mode 100644
index 00000000..cc56da3c
--- /dev/null
+++ b/vendor/libghostty-vt/src/terminal/c/selection_gesture.zig
@@ -0,0 +1,1488 @@
+const std = @import("std");
+const testing = std.testing;
+const builtin = @import("builtin");
+const lib = @import("../lib.zig");
+const CAllocator = lib.alloc.Allocator;
+const SelectionGesture = @import("../SelectionGesture.zig");
+const selection_codepoints = @import("../selection_codepoints.zig");
+const grid_ref = @import("grid_ref.zig");
+const point = @import("../point.zig");
+const selection_c = @import("selection.zig");
+const terminal_c = @import("terminal.zig");
+const types = @import("types.zig");
+const Result = @import("result.zig").Result;
+
+const log = std.log.scoped(.selection_gesture_c);
+
+/// C: GhosttySelectionGesture
+pub const Gesture = ?*GestureWrapper;
+
+/// C: GhosttySelectionGestureEvent
+pub const Event = ?*EventWrapper;
+
+const GestureWrapper = struct {
+    alloc: std.mem.Allocator,
+    gesture: SelectionGesture = .init,
+};
+
+const EventWrapper = struct {
+    alloc: std.mem.Allocator,
+    event: union(EventType) {
+        press: SelectionGesture.Press,
+        release: SelectionGesture.Release,
+        drag: SelectionGesture.Drag,
+        autoscroll_tick: SelectionGesture.AutoscrollTick,
+        deep_press: SelectionGesture.DeepPress,
+    },
+
+    // Validation sidecar for required event fields that don't have safe
+    // sentinels in the real SelectionGesture payloads. For example, PageList.Pin
+    // contains a non-null node pointer and Geometry has no meaningful zero
+    // value. Keep these as one-bit flags so dispatch can reject incomplete C
+    // events instead of using undefined placeholder data.
+    event_validation: packed struct {
+        press_pin_set: bool = false,
+        drag_pin_set: bool = false,
+        drag_geometry_set: bool = false,
+        autoscroll_tick_viewport_set: bool = false,
+        autoscroll_tick_geometry_set: bool = false,
+    } = .{},
+
+    // Backing storage for Press/Drag/AutoscrollTick.word_boundary_codepoints.
+    // The C API receives codepoints as borrowed uint32_t values, but
+    // SelectionGesture stores a []const u21 slice. We copy/convert into
+    // event-owned storage so the real payload can safely point at it until the
+    // event is changed or freed.
+    word_boundary_codepoints: ?[]u21 = null,
+
+    // Backing storage for Press.behaviors. The C API sets behaviors as a value
+    // struct, but SelectionGesture.Press stores a pointer to a [3]Behavior.
+    // Keep the array on the event wrapper so the Press payload can point at a
+    // stable location for the lifetime of the event.
+    behaviors: [3]Behavior = SelectionGesture.default_behaviors,
+
+    fn init(self: *EventWrapper, event_type: EventType) void {
+        self.event = switch (event_type) {
+            .press => .{ .press = self.defaultPress() },
+            .release => .{ .release = self.defaultRelease() },
+            .drag => .{ .drag = self.defaultDrag() },
+            .autoscroll_tick => .{ .autoscroll_tick = self.defaultAutoscrollTick() },
+            .deep_press => .{ .deep_press = self.defaultDeepPress() },
+        };
+    }
+
+    fn defaultPress(self: *EventWrapper) SelectionGesture.Press {
+        return .{
+            .time = null,
+            .pin = undefined,
+            .xpos = 0,
+            .ypos = 0,
+            .max_distance = 0,
+            .repeat_interval = 0,
+            .word_boundary_codepoints = &selection_codepoints.default_word_boundaries,
+            .behaviors = &self.behaviors,
+        };
+    }
+
+    fn defaultRelease(self: *EventWrapper) SelectionGesture.Release {
+        _ = self;
+        return .{ .pin = null };
+    }
+
+    fn defaultDrag(self: *EventWrapper) SelectionGesture.Drag {
+        _ = self;
+        return .{
+            .pin = undefined,
+            .xpos = 0,
+            .ypos = 0,
+            .rectangle = false,
+            .word_boundary_codepoints = &selection_codepoints.default_word_boundaries,
+            .geometry = undefined,
+        };
+    }
+
+    fn defaultAutoscrollTick(self: *EventWrapper) SelectionGesture.AutoscrollTick {
+        _ = self;
+        return .{
+            .viewport = undefined,
+            .xpos = 0,
+            .ypos = 0,
+            .rectangle = false,
+            .word_boundary_codepoints = &selection_codepoints.default_word_boundaries,
+            .geometry = undefined,
+        };
+    }
+
+    fn defaultDeepPress(self: *EventWrapper) SelectionGesture.DeepPress {
+        _ = self;
+        return .{
+            .word_boundary_codepoints = &selection_codepoints.default_word_boundaries,
+        };
+    }
+
+    fn deinit(self: *EventWrapper) void {
+        if (self.word_boundary_codepoints) |cps| {
+            if (cps.len > 0) self.alloc.free(cps);
+        }
+    }
+};
+
+/// C: GhosttySelectionGestureBehavior
+pub const Behavior = SelectionGesture.Behavior;
+
+/// C: GhosttySelectionGestureAutoscroll
+pub const Autoscroll = SelectionGesture.Autoscroll;
+
+/// C: GhosttySelectionGestureBehaviors
+pub const Behaviors = extern struct {
+    single_click: Behavior,
+    double_click: Behavior,
+    triple_click: Behavior,
+};
+
+/// C: GhosttySelectionGestureData
+pub const Data = enum(c_int) {
+    click_count = 0,
+    dragged = 1,
+    autoscroll = 2,
+    behavior = 3,
+    anchor = 4,
+
+    pub fn OutType(comptime self: Data) type {
+        return switch (self) {
+            .click_count => u8,
+            .dragged => bool,
+            .autoscroll => Autoscroll,
+            .behavior => Behavior,
+            .anchor => grid_ref.CGridRef,
+        };
+    }
+};
+
+/// C: GhosttySelectionGestureEventType
+pub const EventType = enum(c_int) {
+    press = 0,
+    release = 1,
+    drag = 2,
+    autoscroll_tick = 3,
+    deep_press = 4,
+};
+
+/// C: GhosttySelectionGestureEventOption
+pub const EventOption = enum(c_int) {
+    ref = 0,
+    position = 1,
+    repeat_distance = 2,
+    time_ns = 3,
+    repeat_interval_ns = 4,
+    word_boundary_codepoints = 5,
+    behaviors = 6,
+    rectangle = 7,
+    geometry = 8,
+    viewport = 9,
+
+    pub fn Type(comptime self: EventOption) type {
+        return switch (self) {
+            .ref => grid_ref.CGridRef,
+            .position => types.SurfacePosition,
+            .repeat_distance => f64,
+            .time_ns => u64,
+            .repeat_interval_ns => u64,
+            .word_boundary_codepoints => types.Codepoints,
+            .behaviors => Behaviors,
+            .rectangle => bool,
+            .geometry => Geometry,
+            .viewport => point.Coordinate,
+        };
+    }
+};
+
+/// C: GhosttySelectionGestureGeometry
+pub const Geometry = extern struct {
+    columns: u32,
+    cell_width: u32,
+    padding_left: u32,
+    screen_height: u32,
+
+    fn toZig(self: Geometry) ?SelectionGesture.Drag.Geometry {
+        if (self.columns == 0) return null;
+        if (self.cell_width == 0) return null;
+        if (self.screen_height == 0) return null;
+        return .{
+            .columns = self.columns,
+            .cell_width = self.cell_width,
+            .padding_left = self.padding_left,
+            .screen_height = self.screen_height,
+        };
+    }
+};
+
+pub fn new(
+    alloc_: ?*const CAllocator,
+    out_gesture: ?*Gesture,
+) callconv(lib.calling_conv) Result {
+    const out = out_gesture orelse return .invalid_value;
+
+    const alloc = lib.alloc.default(alloc_);
+    const gesture = alloc.create(GestureWrapper) catch {
+        out.* = null;
+        return .out_of_memory;
+    };
+    gesture.* = .{
+        .alloc = alloc,
+    };
+    out.* = gesture;
+    return .success;
+}
+
+pub fn event_new(
+    alloc_: ?*const CAllocator,
+    out_event: ?*Event,
+    event_type: EventType,
+) callconv(lib.calling_conv) Result {
+    const out = out_event orelse return .invalid_value;
+    _ = std.meta.intToEnum(EventType, @intFromEnum(event_type)) catch
+        return .invalid_value;
+
+    const alloc = lib.alloc.default(alloc_);
+    const event = alloc.create(EventWrapper) catch {
+        out.* = null;
+        return .out_of_memory;
+    };
+    event.* = .{
+        .alloc = alloc,
+        .event = undefined,
+    };
+    event.init(event_type);
+    out.* = event;
+    return .success;
+}
+
+pub fn free(
+    gesture_: Gesture,
+    terminal: terminal_c.Terminal,
+) callconv(lib.calling_conv) void {
+    const wrapper = gesture_ orelse return;
+    if (terminal_c.zigTerminal(terminal)) |t| {
+        wrapper.gesture.deinit(t);
+    }
+    const alloc = wrapper.alloc;
+    alloc.destroy(wrapper);
+}
+
+pub fn event_free(event_: Event) callconv(lib.calling_conv) void {
+    const event = event_ orelse return;
+    event.deinit();
+    const alloc = event.alloc;
+    alloc.destroy(event);
+}
+
+pub fn reset(
+    gesture_: Gesture,
+    terminal: terminal_c.Terminal,
+) callconv(lib.calling_conv) void {
+    const wrapper = gesture_ orelse return;
+    const t = terminal_c.zigTerminal(terminal) orelse return;
+    wrapper.gesture.reset(t);
+}
+
+pub fn handle_event(
+    gesture_: Gesture,
+    terminal: terminal_c.Terminal,
+    event_: Event,
+    out_selection: ?*selection_c.CSelection,
+) callconv(lib.calling_conv) Result {
+    const wrapper = gesture_ orelse return .invalid_value;
+    const t = terminal_c.zigTerminal(terminal) orelse return .invalid_value;
+    const event_wrapper = event_ orelse return .invalid_value;
+
+    return switch (event_wrapper.event) {
+        .press => |press| {
+            if (!event_wrapper.event_validation.press_pin_set) return .invalid_value;
+            const sel = wrapper.gesture.press(t, press) catch return .out_of_memory;
+            if (out_selection) |out| {
+                out.* = selection_c.CSelection.fromZig(sel orelse return .no_value);
+            } else if (sel == null) return .no_value;
+            return .success;
+        },
+        .release => |release| {
+            wrapper.gesture.release(t, release);
+            return .no_value;
+        },
+        .drag => |drag| {
+            if (!event_wrapper.event_validation.drag_pin_set) return .invalid_value;
+            if (!event_wrapper.event_validation.drag_geometry_set) return .invalid_value;
+            const sel = wrapper.gesture.drag(t, drag);
+            if (out_selection) |out| {
+                out.* = selection_c.CSelection.fromZig(sel orelse return .no_value);
+            } else if (sel == null) return .no_value;
+            return .success;
+        },
+        .autoscroll_tick => |tick| {
+            if (!event_wrapper.event_validation.autoscroll_tick_viewport_set) return .invalid_value;
+            if (!event_wrapper.event_validation.autoscroll_tick_geometry_set) return .invalid_value;
+            const sel = wrapper.gesture.autoscrollTick(t, tick);
+            if (out_selection) |out| {
+                out.* = selection_c.CSelection.fromZig(sel orelse return .no_value);
+            } else if (sel == null) return .no_value;
+            return .success;
+        },
+        .deep_press => |deep_press| {
+            const sel = wrapper.gesture.deepPress(t, deep_press);
+            if (out_selection) |out| {
+                out.* = selection_c.CSelection.fromZig(sel orelse return .no_value);
+            } else if (sel == null) return .no_value;
+            return .success;
+        },
+    };
+}
+
+pub fn event_set(
+    event_: Event,
+    option: EventOption,
+    value: ?*const anyopaque,
+) callconv(lib.calling_conv) Result {
+    if (comptime std.debug.runtime_safety) {
+        _ = std.meta.intToEnum(EventOption, @intFromEnum(option)) catch {
+            log.warn("selection_gesture_event_set invalid option value={d}", .{@intFromEnum(option)});
+            return .invalid_value;
+        };
+    }
+
+    return switch (option) {
+        inline else => |comptime_option| eventSetTyped(
+            event_,
+            comptime_option,
+            if (value) |ptr| @ptrCast(@alignCast(ptr)) else null,
+        ),
+    };
+}
+
+pub fn get(
+    gesture_: Gesture,
+    terminal: terminal_c.Terminal,
+    data: Data,
+    out: ?*anyopaque,
+) callconv(lib.calling_conv) Result {
+    if (comptime std.debug.runtime_safety) {
+        _ = std.meta.intToEnum(Data, @intFromEnum(data)) catch {
+            log.warn("selection_gesture_get invalid data value={d}", .{@intFromEnum(data)});
+            return .invalid_value;
+        };
+    }
+
+    const out_ptr = out orelse return .invalid_value;
+    return switch (data) {
+        inline else => |comptime_data| getTyped(
+            gesture_,
+            terminal,
+            comptime_data,
+            @ptrCast(@alignCast(out_ptr)),
+        ),
+    };
+}
+
+pub fn get_multi(
+    gesture_: Gesture,
+    terminal: terminal_c.Terminal,
+    count: usize,
+    keys: ?[*]const Data,
+    values: ?[*]?*anyopaque,
+    out_written: ?*usize,
+) callconv(lib.calling_conv) Result {
+    const k = keys orelse return .invalid_value;
+    const v = values orelse return .invalid_value;
+
+    for (0..count) |i| {
+        const result = get(gesture_, terminal, k[i], v[i]);
+        if (result != .success) {
+            if (out_written) |w| w.* = i;
+            return result;
+        }
+    }
+    if (out_written) |w| w.* = count;
+    return .success;
+}
+
+fn getTyped(
+    gesture_: Gesture,
+    terminal: terminal_c.Terminal,
+    comptime data: Data,
+    out: *data.OutType(),
+) Result {
+    const wrapper = gesture_ orelse return .invalid_value;
+    const t = terminal_c.zigTerminal(terminal) orelse return .invalid_value;
+
+    switch (data) {
+        .click_count => out.* = wrapper.gesture.left_click_count,
+        .dragged => out.* = wrapper.gesture.left_click_dragged,
+        .autoscroll => out.* = wrapper.gesture.left_drag_autoscroll,
+        .behavior => out.* = wrapper.gesture.left_click_behavior,
+        .anchor => {
+            const pin = wrapper.gesture.validatedLeftClickPin(&t.screens) orelse
+                return .no_value;
+            out.* = .fromPin(pin.*);
+        },
+    }
+
+    return .success;
+}
+
+fn eventSetTyped(
+    event_: Event,
+    comptime option: EventOption,
+    value: ?*const option.Type(),
+) Result {
+    const event = event_ orelse return .invalid_value;
+    return switch (event.event) {
+        .press => |*press| pressSetTyped(event, press, option, value),
+        .release => |*release| releaseSetTyped(release, option, value),
+        .drag => |*drag| dragSetTyped(event, drag, option, value),
+        .autoscroll_tick => |*tick| autoscrollTickSetTyped(event, tick, option, value),
+        .deep_press => |*deep_press| deepPressSetTyped(event, deep_press, option, value),
+    };
+}
+
+fn pressSetTyped(
+    event: *EventWrapper,
+    press: *SelectionGesture.Press,
+    comptime option: EventOption,
+    value: ?*const option.Type(),
+) Result {
+    const v = value orelse {
+        switch (option) {
+            .ref => event.event_validation.press_pin_set = false,
+            .position => {
+                press.xpos = 0;
+                press.ypos = 0;
+            },
+            .repeat_distance => press.max_distance = 0,
+            .time_ns => press.time = null,
+            .repeat_interval_ns => press.repeat_interval = 0,
+            .word_boundary_codepoints => clearWordBoundaryCodepoints(
+                event,
+                &press.word_boundary_codepoints,
+            ),
+            .behaviors => {
+                event.behaviors = SelectionGesture.default_behaviors;
+                press.behaviors = &event.behaviors;
+            },
+            .rectangle,
+            .geometry,
+            .viewport,
+            => return .invalid_value,
+        }
+        return .success;
+    };
+
+    switch (option) {
+        .ref => {
+            press.pin = v.toPin() orelse return .invalid_value;
+            event.event_validation.press_pin_set = true;
+        },
+        .position => {
+            press.xpos = v.x;
+            press.ypos = v.y;
+        },
+        .repeat_distance => press.max_distance = v.*,
+        .time_ns => press.time = instantFromNs(v.*),
+        .repeat_interval_ns => press.repeat_interval = v.*,
+        .word_boundary_codepoints => return trySetWordBoundaryCodepoints(
+            event,
+            &press.word_boundary_codepoints,
+            v,
+        ),
+        .behaviors => {
+            if (!validBehavior(v.single_click) or
+                !validBehavior(v.double_click) or
+                !validBehavior(v.triple_click)) return .invalid_value;
+            event.behaviors = .{ v.single_click, v.double_click, v.triple_click };
+            press.behaviors = &event.behaviors;
+        },
+        .rectangle,
+        .geometry,
+        .viewport,
+        => return .invalid_value,
+    }
+
+    return .success;
+}
+
+fn releaseSetTyped(
+    release: *SelectionGesture.Release,
+    comptime option: EventOption,
+    value: ?*const option.Type(),
+) Result {
+    switch (option) {
+        .ref => {
+            const v = value orelse {
+                release.pin = null;
+                return .success;
+            };
+            release.pin = v.toPin() orelse return .invalid_value;
+        },
+
+        .position,
+        .repeat_distance,
+        .time_ns,
+        .repeat_interval_ns,
+        .word_boundary_codepoints,
+        .behaviors,
+        .rectangle,
+        .geometry,
+        .viewport,
+        => return .invalid_value,
+    }
+
+    return .success;
+}
+
+fn dragSetTyped(
+    event: *EventWrapper,
+    drag: *SelectionGesture.Drag,
+    comptime option: EventOption,
+    value: ?*const option.Type(),
+) Result {
+    const v = value orelse {
+        switch (option) {
+            .ref => event.event_validation.drag_pin_set = false,
+            .position => {
+                drag.xpos = 0;
+                drag.ypos = 0;
+            },
+            .word_boundary_codepoints => clearWordBoundaryCodepoints(
+                event,
+                &drag.word_boundary_codepoints,
+            ),
+            .rectangle => drag.rectangle = false,
+            .geometry => event.event_validation.drag_geometry_set = false,
+            .viewport => return .invalid_value,
+
+            .repeat_distance,
+            .time_ns,
+            .repeat_interval_ns,
+            .behaviors,
+            => return .invalid_value,
+        }
+        return .success;
+    };
+
+    switch (option) {
+        .ref => {
+            drag.pin = v.toPin() orelse return .invalid_value;
+            event.event_validation.drag_pin_set = true;
+        },
+        .position => {
+            drag.xpos = v.x;
+            drag.ypos = v.y;
+        },
+        .word_boundary_codepoints => return trySetWordBoundaryCodepoints(
+            event,
+            &drag.word_boundary_codepoints,
+            v,
+        ),
+        .rectangle => drag.rectangle = v.*,
+        .geometry => {
+            drag.geometry = v.toZig() orelse return .invalid_value;
+            event.event_validation.drag_geometry_set = true;
+        },
+        .viewport => return .invalid_value,
+
+        .repeat_distance,
+        .time_ns,
+        .repeat_interval_ns,
+        .behaviors,
+        => return .invalid_value,
+    }
+
+    return .success;
+}
+
+fn autoscrollTickSetTyped(
+    event: *EventWrapper,
+    tick: *SelectionGesture.AutoscrollTick,
+    comptime option: EventOption,
+    value: ?*const option.Type(),
+) Result {
+    const v = value orelse {
+        switch (option) {
+            .viewport => event.event_validation.autoscroll_tick_viewport_set = false,
+            .position => {
+                tick.xpos = 0;
+                tick.ypos = 0;
+            },
+            .word_boundary_codepoints => clearWordBoundaryCodepoints(
+                event,
+                &tick.word_boundary_codepoints,
+            ),
+            .rectangle => tick.rectangle = false,
+            .geometry => event.event_validation.autoscroll_tick_geometry_set = false,
+
+            .ref,
+            .repeat_distance,
+            .time_ns,
+            .repeat_interval_ns,
+            .behaviors,
+            => return .invalid_value,
+        }
+        return .success;
+    };
+
+    switch (option) {
+        .viewport => {
+            tick.viewport = v.*;
+            event.event_validation.autoscroll_tick_viewport_set = true;
+        },
+        .position => {
+            tick.xpos = v.x;
+            tick.ypos = v.y;
+        },
+        .word_boundary_codepoints => return trySetWordBoundaryCodepoints(
+            event,
+            &tick.word_boundary_codepoints,
+            v,
+        ),
+        .rectangle => tick.rectangle = v.*,
+        .geometry => {
+            tick.geometry = v.toZig() orelse return .invalid_value;
+            event.event_validation.autoscroll_tick_geometry_set = true;
+        },
+
+        .ref,
+        .repeat_distance,
+        .time_ns,
+        .repeat_interval_ns,
+        .behaviors,
+        => return .invalid_value,
+    }
+
+    return .success;
+}
+
+fn deepPressSetTyped(
+    event: *EventWrapper,
+    deep_press: *SelectionGesture.DeepPress,
+    comptime option: EventOption,
+    value: ?*const option.Type(),
+) Result {
+    const v = value orelse {
+        switch (option) {
+            .word_boundary_codepoints => clearWordBoundaryCodepoints(
+                event,
+                &deep_press.word_boundary_codepoints,
+            ),
+
+            .ref,
+            .position,
+            .repeat_distance,
+            .time_ns,
+            .repeat_interval_ns,
+            .behaviors,
+            .rectangle,
+            .geometry,
+            .viewport,
+            => return .invalid_value,
+        }
+        return .success;
+    };
+
+    switch (option) {
+        .word_boundary_codepoints => return trySetWordBoundaryCodepoints(
+            event,
+            &deep_press.word_boundary_codepoints,
+            v,
+        ),
+
+        .ref,
+        .position,
+        .repeat_distance,
+        .time_ns,
+        .repeat_interval_ns,
+        .behaviors,
+        .rectangle,
+        .geometry,
+        .viewport,
+        => return .invalid_value,
+    }
+
+    return .success;
+}
+
+fn trySetWordBoundaryCodepoints(
+    event: *EventWrapper,
+    target: *[]const u21,
+    value: *const types.Codepoints,
+) Result {
+    if (value.len > 0 and value.ptr == null) return .invalid_value;
+    clearWordBoundaryCodepoints(event, target);
+    const ptr = value.ptr orelse {
+        event.word_boundary_codepoints = &.{};
+        target.* = event.word_boundary_codepoints.?;
+        return .success;
+    };
+    const copy = event.alloc.alloc(u21, value.len) catch return .out_of_memory;
+    errdefer event.alloc.free(copy);
+    for (copy, ptr[0..value.len]) |*dst, cp| {
+        dst.* = std.math.cast(u21, cp) orelse return .invalid_value;
+    }
+    event.word_boundary_codepoints = copy;
+    target.* = copy;
+    return .success;
+}
+
+fn clearWordBoundaryCodepoints(event: *EventWrapper, target: *[]const u21) void {
+    if (event.word_boundary_codepoints) |cps| {
+        if (cps.len > 0) event.alloc.free(cps);
+    }
+    event.word_boundary_codepoints = null;
+    target.* = &selection_codepoints.default_word_boundaries;
+}
+
+fn instantFromNs(ns: u64) SelectionGesture.Time {
+    if (comptime builtin.target.cpu.arch == .wasm32 and
+        builtin.target.os.tag == .freestanding)
+    {
+        return ns;
+    }
+
+    return switch (builtin.os.tag) {
+        .windows, .uefi, .wasi => .{ .timestamp = ns },
+        else => .{ .timestamp = .{
+            .sec = @intCast(ns / std.time.ns_per_s),
+            .nsec = @intCast(ns % std.time.ns_per_s),
+        } },
+    };
+}
+
+fn validBehavior(behavior: Behavior) bool {
+    _ = std.meta.intToEnum(Behavior, @intFromEnum(behavior)) catch return false;
+    return true;
+}
+
+test "selection gesture lifecycle and get" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{ .cols = 5, .rows = 2, .max_scrollback = 10_000 },
+    ));
+    defer terminal_c.free(terminal);
+
+    var gesture: Gesture = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &gesture,
+    ));
+    defer free(gesture, terminal);
+
+    var click_count: u8 = 255;
+    try testing.expectEqual(Result.success, get(gesture, terminal, .click_count, &click_count));
+    try testing.expectEqual(@as(u8, 0), click_count);
+
+    var dragged = true;
+    try testing.expectEqual(Result.success, get(gesture, terminal, .dragged, &dragged));
+    try testing.expect(!dragged);
+
+    var autoscroll: Autoscroll = .up;
+    try testing.expectEqual(Result.success, get(gesture, terminal, .autoscroll, &autoscroll));
+    try testing.expectEqual(Autoscroll.none, autoscroll);
+
+    var behavior: Behavior = .word;
+    try testing.expectEqual(Result.success, get(gesture, terminal, .behavior, &behavior));
+    try testing.expectEqual(Behavior.cell, behavior);
+
+    var anchor: grid_ref.CGridRef = undefined;
+    try testing.expectEqual(Result.no_value, get(gesture, terminal, .anchor, &anchor));
+}
+
+test "selection gesture get_multi" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{ .cols = 5, .rows = 2, .max_scrollback = 10_000 },
+    ));
+    defer terminal_c.free(terminal);
+
+    var gesture: Gesture = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &gesture,
+    ));
+    defer free(gesture, terminal);
+
+    const keys = [_]Data{ .click_count, .dragged, .autoscroll, .behavior };
+    var click_count: u8 = 255;
+    var dragged = true;
+    var autoscroll: Autoscroll = .up;
+    var behavior: Behavior = .word;
+    var values = [_]?*anyopaque{
+        &click_count,
+        &dragged,
+        &autoscroll,
+        &behavior,
+    };
+    var written: usize = 0;
+
+    try testing.expectEqual(Result.success, get_multi(
+        gesture,
+        terminal,
+        keys.len,
+        &keys,
+        &values,
+        &written,
+    ));
+    try testing.expectEqual(keys.len, written);
+    try testing.expectEqual(@as(u8, 0), click_count);
+    try testing.expect(!dragged);
+    try testing.expectEqual(Autoscroll.none, autoscroll);
+    try testing.expectEqual(Behavior.cell, behavior);
+}
+
+test "selection gesture get_multi returns first failing index" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{ .cols = 5, .rows = 2, .max_scrollback = 10_000 },
+    ));
+    defer terminal_c.free(terminal);
+
+    var gesture: Gesture = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &gesture,
+    ));
+    defer free(gesture, terminal);
+
+    const keys = [_]Data{ .click_count, .anchor, .dragged };
+    var click_count: u8 = 255;
+    var anchor: grid_ref.CGridRef = undefined;
+    var dragged = true;
+    var values = [_]?*anyopaque{ &click_count, &anchor, &dragged };
+    var written: usize = 0;
+
+    try testing.expectEqual(Result.no_value, get_multi(
+        gesture,
+        terminal,
+        keys.len,
+        &keys,
+        &values,
+        &written,
+    ));
+    try testing.expectEqual(@as(usize, 1), written);
+    try testing.expectEqual(@as(u8, 0), click_count);
+    try testing.expect(dragged);
+}
+
+test "selection gesture event set clear and free" {
+    var event: Event = null;
+    try testing.expectEqual(Result.success, event_new(
+        &lib.alloc.test_allocator,
+        &event,
+        .press,
+    ));
+    defer event_free(event);
+
+    const in_pos: types.SurfacePosition = .{ .x = 12.5, .y = -3.25 };
+    try testing.expectEqual(Result.success, event_set(event, .position, &in_pos));
+    try testing.expectEqual(@as(f64, 12.5), event.?.event.press.xpos);
+    try testing.expectEqual(@as(f64, -3.25), event.?.event.press.ypos);
+
+    try testing.expectEqual(Result.success, event_set(event, .position, null));
+    try testing.expectEqual(@as(f64, 0), event.?.event.press.xpos);
+    try testing.expectEqual(@as(f64, 0), event.?.event.press.ypos);
+
+    const repeat_distance: f64 = 4.0;
+    try testing.expectEqual(Result.success, event_set(event, .repeat_distance, &repeat_distance));
+    try testing.expectEqual(repeat_distance, event.?.event.press.max_distance);
+}
+
+test "selection gesture event copies clears and frees codepoints" {
+    var event: Event = null;
+    try testing.expectEqual(Result.success, event_new(
+        &lib.alloc.test_allocator,
+        &event,
+        .press,
+    ));
+    defer event_free(event);
+
+    var values = [_]u32{ ' ', '\t' };
+    const in: types.Codepoints = .{ .ptr = &values, .len = values.len };
+    try testing.expectEqual(Result.success, event_set(event, .word_boundary_codepoints, &in));
+
+    values[0] = 'x';
+
+    try testing.expectEqual(@as(usize, 2), event.?.event.press.word_boundary_codepoints.len);
+    try testing.expectEqual(@as(u21, ' '), event.?.event.press.word_boundary_codepoints[0]);
+    try testing.expectEqual(@as(u21, '\t'), event.?.event.press.word_boundary_codepoints[1]);
+
+    const invalid: types.Codepoints = .{ .ptr = null, .len = 1 };
+    try testing.expectEqual(Result.invalid_value, event_set(event, .word_boundary_codepoints, &invalid));
+
+    try testing.expectEqual(Result.success, event_set(event, .word_boundary_codepoints, null));
+    try testing.expectEqual(
+        selection_codepoints.default_word_boundaries.len,
+        event.?.event.press.word_boundary_codepoints.len,
+    );
+
+    const empty: types.Codepoints = .{ .ptr = null, .len = 0 };
+    try testing.expectEqual(Result.success, event_set(event, .word_boundary_codepoints, &empty));
+    try testing.expectEqual(@as(usize, 0), event.?.event.press.word_boundary_codepoints.len);
+}
+
+test "selection gesture event behaviors" {
+    var event: Event = null;
+    try testing.expectEqual(Result.success, event_new(
+        &lib.alloc.test_allocator,
+        &event,
+        .press,
+    ));
+    defer event_free(event);
+
+    const in: Behaviors = .{
+        .single_click = .cell,
+        .double_click = .word,
+        .triple_click = .line,
+    };
+    try testing.expectEqual(Result.success, event_set(event, .behaviors, &in));
+    try testing.expectEqual(Behavior.cell, event.?.event.press.behaviors[0]);
+    try testing.expectEqual(Behavior.word, event.?.event.press.behaviors[1]);
+    try testing.expectEqual(Behavior.line, event.?.event.press.behaviors[2]);
+}
+
+test "selection gesture event applies press" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{ .cols = 5, .rows = 2, .max_scrollback = 10_000 },
+    ));
+    defer terminal_c.free(terminal);
+
+    var gesture: Gesture = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &gesture,
+    ));
+    defer free(gesture, terminal);
+
+    var press_event: Event = null;
+    try testing.expectEqual(Result.success, event_new(
+        &lib.alloc.test_allocator,
+        &press_event,
+        .press,
+    ));
+    defer event_free(press_event);
+
+    terminal_c.vt_write(terminal, "abc", 3);
+
+    var ref: grid_ref.CGridRef = undefined;
+    try testing.expectEqual(Result.success, terminal_c.grid_ref(terminal, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 1, .y = 0 } },
+    }, &ref));
+    try testing.expectEqual(Result.success, event_set(press_event, .ref, &ref));
+    const behaviors: Behaviors = .{
+        .single_click = .word,
+        .double_click = .word,
+        .triple_click = .line,
+    };
+    try testing.expectEqual(Result.success, event_set(press_event, .behaviors, &behaviors));
+
+    var sel: selection_c.CSelection = undefined;
+    try testing.expectEqual(Result.success, handle_event(gesture, terminal, press_event, &sel));
+    try testing.expectEqual(@as(u16, 0), sel.start.toPin().?.x);
+    try testing.expectEqual(@as(u16, 2), sel.end.toPin().?.x);
+
+    try testing.expectEqual(Result.success, handle_event(gesture, terminal, press_event, null));
+}
+
+test "selection gesture event press requires ref" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{ .cols = 5, .rows = 2, .max_scrollback = 10_000 },
+    ));
+    defer terminal_c.free(terminal);
+
+    var gesture: Gesture = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &gesture,
+    ));
+    defer free(gesture, terminal);
+
+    var press_event: Event = null;
+    try testing.expectEqual(Result.success, event_new(
+        &lib.alloc.test_allocator,
+        &press_event,
+        .press,
+    ));
+    defer event_free(press_event);
+
+    var sel: selection_c.CSelection = undefined;
+    try testing.expectEqual(Result.invalid_value, handle_event(gesture, terminal, press_event, &sel));
+}
+
+test "selection gesture event null output still reports no selection" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{ .cols = 5, .rows = 2, .max_scrollback = 10_000 },
+    ));
+    defer terminal_c.free(terminal);
+
+    var gesture: Gesture = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &gesture,
+    ));
+    defer free(gesture, terminal);
+
+    var press_event: Event = null;
+    try testing.expectEqual(Result.success, event_new(
+        &lib.alloc.test_allocator,
+        &press_event,
+        .press,
+    ));
+    defer event_free(press_event);
+
+    var ref: grid_ref.CGridRef = undefined;
+    try testing.expectEqual(Result.success, terminal_c.grid_ref(terminal, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 1, .y = 0 } },
+    }, &ref));
+    try testing.expectEqual(Result.success, event_set(press_event, .ref, &ref));
+
+    try testing.expectEqual(Result.no_value, handle_event(gesture, terminal, press_event, null));
+}
+
+test "selection gesture event applies release" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{ .cols = 5, .rows = 2, .max_scrollback = 10_000 },
+    ));
+    defer terminal_c.free(terminal);
+
+    var gesture: Gesture = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &gesture,
+    ));
+    defer free(gesture, terminal);
+
+    var press_event: Event = null;
+    try testing.expectEqual(Result.success, event_new(
+        &lib.alloc.test_allocator,
+        &press_event,
+        .press,
+    ));
+    defer event_free(press_event);
+
+    var release_event: Event = null;
+    try testing.expectEqual(Result.success, event_new(
+        &lib.alloc.test_allocator,
+        &release_event,
+        .release,
+    ));
+    defer event_free(release_event);
+
+    var ref: grid_ref.CGridRef = undefined;
+    try testing.expectEqual(Result.success, terminal_c.grid_ref(terminal, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 1, .y = 0 } },
+    }, &ref));
+    try testing.expectEqual(Result.success, event_set(press_event, .ref, &ref));
+    try testing.expectEqual(Result.success, event_set(release_event, .ref, &ref));
+
+    try testing.expectEqual(Result.no_value, handle_event(gesture, terminal, press_event, null));
+    try testing.expectEqual(Result.no_value, handle_event(gesture, terminal, release_event, null));
+
+    var dragged = true;
+    try testing.expectEqual(Result.success, get(gesture, terminal, .dragged, &dragged));
+    try testing.expect(!dragged);
+
+    const pos: types.SurfacePosition = .{ .x = 0, .y = 0 };
+    try testing.expectEqual(Result.invalid_value, event_set(release_event, .position, &pos));
+}
+
+test "selection gesture release without ref marks dragged" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{ .cols = 5, .rows = 2, .max_scrollback = 10_000 },
+    ));
+    defer terminal_c.free(terminal);
+
+    var gesture: Gesture = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &gesture,
+    ));
+    defer free(gesture, terminal);
+
+    var press_event: Event = null;
+    try testing.expectEqual(Result.success, event_new(
+        &lib.alloc.test_allocator,
+        &press_event,
+        .press,
+    ));
+    defer event_free(press_event);
+
+    var release_event: Event = null;
+    try testing.expectEqual(Result.success, event_new(
+        &lib.alloc.test_allocator,
+        &release_event,
+        .release,
+    ));
+    defer event_free(release_event);
+
+    var ref: grid_ref.CGridRef = undefined;
+    try testing.expectEqual(Result.success, terminal_c.grid_ref(terminal, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 1, .y = 0 } },
+    }, &ref));
+    try testing.expectEqual(Result.success, event_set(press_event, .ref, &ref));
+
+    try testing.expectEqual(Result.no_value, handle_event(gesture, terminal, press_event, null));
+    try testing.expectEqual(Result.no_value, handle_event(gesture, terminal, release_event, null));
+
+    var dragged = false;
+    try testing.expectEqual(Result.success, get(gesture, terminal, .dragged, &dragged));
+    try testing.expect(dragged);
+}
+
+test "selection gesture event applies drag" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{ .cols = 5, .rows = 2, .max_scrollback = 10_000 },
+    ));
+    defer terminal_c.free(terminal);
+
+    terminal_c.vt_write(terminal, "abcde", 5);
+
+    var gesture: Gesture = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &gesture,
+    ));
+    defer free(gesture, terminal);
+
+    var press_event: Event = null;
+    try testing.expectEqual(Result.success, event_new(
+        &lib.alloc.test_allocator,
+        &press_event,
+        .press,
+    ));
+    defer event_free(press_event);
+
+    var drag_event: Event = null;
+    try testing.expectEqual(Result.success, event_new(
+        &lib.alloc.test_allocator,
+        &drag_event,
+        .drag,
+    ));
+    defer event_free(drag_event);
+
+    var press_ref: grid_ref.CGridRef = undefined;
+    try testing.expectEqual(Result.success, terminal_c.grid_ref(terminal, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 1, .y = 0 } },
+    }, &press_ref));
+    try testing.expectEqual(Result.success, event_set(press_event, .ref, &press_ref));
+
+    const press_pos: types.SurfacePosition = .{ .x = 10, .y = 10 };
+    try testing.expectEqual(Result.success, event_set(press_event, .position, &press_pos));
+    try testing.expectEqual(Result.no_value, handle_event(gesture, terminal, press_event, null));
+
+    var drag_ref: grid_ref.CGridRef = undefined;
+    try testing.expectEqual(Result.success, terminal_c.grid_ref(terminal, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 3, .y = 0 } },
+    }, &drag_ref));
+    try testing.expectEqual(Result.success, event_set(drag_event, .ref, &drag_ref));
+
+    const drag_pos: types.SurfacePosition = .{ .x = 36, .y = 10 };
+    try testing.expectEqual(Result.success, event_set(drag_event, .position, &drag_pos));
+    const geometry: Geometry = .{
+        .columns = 5,
+        .cell_width = 10,
+        .padding_left = 0,
+        .screen_height = 20,
+    };
+    try testing.expectEqual(Result.success, event_set(drag_event, .geometry, &geometry));
+
+    var sel: selection_c.CSelection = undefined;
+    try testing.expectEqual(Result.success, handle_event(gesture, terminal, drag_event, &sel));
+    try testing.expectEqual(@as(u16, 1), sel.start.toPin().?.x);
+    try testing.expectEqual(@as(u16, 3), sel.end.toPin().?.x);
+
+    var dragged = false;
+    try testing.expectEqual(Result.success, get(gesture, terminal, .dragged, &dragged));
+    try testing.expect(dragged);
+}
+
+test "selection gesture drag requires ref and geometry" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{ .cols = 5, .rows = 2, .max_scrollback = 10_000 },
+    ));
+    defer terminal_c.free(terminal);
+
+    var gesture: Gesture = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &gesture,
+    ));
+    defer free(gesture, terminal);
+
+    var drag_event: Event = null;
+    try testing.expectEqual(Result.success, event_new(
+        &lib.alloc.test_allocator,
+        &drag_event,
+        .drag,
+    ));
+    defer event_free(drag_event);
+
+    var sel: selection_c.CSelection = undefined;
+    try testing.expectEqual(Result.invalid_value, handle_event(gesture, terminal, drag_event, &sel));
+
+    var ref: grid_ref.CGridRef = undefined;
+    try testing.expectEqual(Result.success, terminal_c.grid_ref(terminal, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 1, .y = 0 } },
+    }, &ref));
+    try testing.expectEqual(Result.success, event_set(drag_event, .ref, &ref));
+    try testing.expectEqual(Result.invalid_value, handle_event(gesture, terminal, drag_event, &sel));
+
+    const invalid_geometry: Geometry = .{
+        .columns = 5,
+        .cell_width = 0,
+        .padding_left = 0,
+        .screen_height = 20,
+    };
+    try testing.expectEqual(Result.invalid_value, event_set(drag_event, .geometry, &invalid_geometry));
+}
+
+test "selection gesture event applies autoscroll tick" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{ .cols = 5, .rows = 2, .max_scrollback = 10_000 },
+    ));
+    defer terminal_c.free(terminal);
+
+    terminal_c.vt_write(terminal, "abcde\r\nfghij", 12);
+
+    var gesture: Gesture = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &gesture,
+    ));
+    defer free(gesture, terminal);
+
+    var press_event: Event = null;
+    try testing.expectEqual(Result.success, event_new(
+        &lib.alloc.test_allocator,
+        &press_event,
+        .press,
+    ));
+    defer event_free(press_event);
+
+    var drag_event: Event = null;
+    try testing.expectEqual(Result.success, event_new(
+        &lib.alloc.test_allocator,
+        &drag_event,
+        .drag,
+    ));
+    defer event_free(drag_event);
+
+    var tick_event: Event = null;
+    try testing.expectEqual(Result.success, event_new(
+        &lib.alloc.test_allocator,
+        &tick_event,
+        .autoscroll_tick,
+    ));
+    defer event_free(tick_event);
+
+    const geometry: Geometry = .{
+        .columns = 5,
+        .cell_width = 10,
+        .padding_left = 0,
+        .screen_height = 20,
+    };
+
+    var press_ref: grid_ref.CGridRef = undefined;
+    try testing.expectEqual(Result.success, terminal_c.grid_ref(terminal, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 1, .y = 0 } },
+    }, &press_ref));
+    try testing.expectEqual(Result.success, event_set(press_event, .ref, &press_ref));
+    const press_pos: types.SurfacePosition = .{ .x = 10, .y = 10 };
+    try testing.expectEqual(Result.success, event_set(press_event, .position, &press_pos));
+    try testing.expectEqual(Result.no_value, handle_event(gesture, terminal, press_event, null));
+
+    var drag_ref: grid_ref.CGridRef = undefined;
+    try testing.expectEqual(Result.success, terminal_c.grid_ref(terminal, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 3, .y = 1 } },
+    }, &drag_ref));
+    try testing.expectEqual(Result.success, event_set(drag_event, .ref, &drag_ref));
+    const drag_pos: types.SurfacePosition = .{ .x = 36, .y = 20 };
+    try testing.expectEqual(Result.success, event_set(drag_event, .position, &drag_pos));
+    try testing.expectEqual(Result.success, event_set(drag_event, .geometry, &geometry));
+    var sel: selection_c.CSelection = undefined;
+    try testing.expectEqual(Result.success, handle_event(gesture, terminal, drag_event, &sel));
+
+    var autoscroll: Autoscroll = .none;
+    try testing.expectEqual(Result.success, get(gesture, terminal, .autoscroll, &autoscroll));
+    try testing.expectEqual(Autoscroll.down, autoscroll);
+
+    const viewport: point.Coordinate = .{ .x = 3, .y = 1 };
+    try testing.expectEqual(Result.success, event_set(tick_event, .viewport, &viewport));
+    try testing.expectEqual(Result.success, event_set(tick_event, .position, &drag_pos));
+    try testing.expectEqual(Result.success, event_set(tick_event, .geometry, &geometry));
+
+    try testing.expectEqual(Result.success, handle_event(gesture, terminal, tick_event, &sel));
+}
+
+test "selection gesture autoscroll tick requires viewport and geometry" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{ .cols = 5, .rows = 2, .max_scrollback = 10_000 },
+    ));
+    defer terminal_c.free(terminal);
+
+    var gesture: Gesture = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &gesture,
+    ));
+    defer free(gesture, terminal);
+
+    var tick_event: Event = null;
+    try testing.expectEqual(Result.success, event_new(
+        &lib.alloc.test_allocator,
+        &tick_event,
+        .autoscroll_tick,
+    ));
+    defer event_free(tick_event);
+
+    var sel: selection_c.CSelection = undefined;
+    try testing.expectEqual(Result.invalid_value, handle_event(gesture, terminal, tick_event, &sel));
+
+    const viewport: point.Coordinate = .{ .x = 1, .y = 0 };
+    try testing.expectEqual(Result.success, event_set(tick_event, .viewport, &viewport));
+    try testing.expectEqual(Result.invalid_value, handle_event(gesture, terminal, tick_event, &sel));
+
+    var ref: grid_ref.CGridRef = undefined;
+    try testing.expectEqual(Result.success, terminal_c.grid_ref(terminal, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 1, .y = 0 } },
+    }, &ref));
+    try testing.expectEqual(Result.invalid_value, event_set(tick_event, .ref, &ref));
+}
+
+test "selection gesture event applies deep press" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{ .cols = 5, .rows = 2, .max_scrollback = 10_000 },
+    ));
+    defer terminal_c.free(terminal);
+
+    terminal_c.vt_write(terminal, "abcde", 5);
+
+    var gesture: Gesture = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &gesture,
+    ));
+    defer free(gesture, terminal);
+
+    var press_event: Event = null;
+    try testing.expectEqual(Result.success, event_new(
+        &lib.alloc.test_allocator,
+        &press_event,
+        .press,
+    ));
+    defer event_free(press_event);
+
+    var deep_press_event: Event = null;
+    try testing.expectEqual(Result.success, event_new(
+        &lib.alloc.test_allocator,
+        &deep_press_event,
+        .deep_press,
+    ));
+    defer event_free(deep_press_event);
+
+    var ref: grid_ref.CGridRef = undefined;
+    try testing.expectEqual(Result.success, terminal_c.grid_ref(terminal, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 2, .y = 0 } },
+    }, &ref));
+    try testing.expectEqual(Result.success, event_set(press_event, .ref, &ref));
+    try testing.expectEqual(Result.no_value, handle_event(gesture, terminal, press_event, null));
+
+    var sel: selection_c.CSelection = undefined;
+    try testing.expectEqual(Result.success, handle_event(gesture, terminal, deep_press_event, &sel));
+    try testing.expectEqual(@as(u16, 0), sel.start.toPin().?.x);
+    try testing.expectEqual(@as(u16, 4), sel.end.toPin().?.x);
+
+    var dragged = false;
+    try testing.expectEqual(Result.success, get(gesture, terminal, .dragged, &dragged));
+    try testing.expect(dragged);
+
+    const pos: types.SurfacePosition = .{ .x = 0, .y = 0 };
+    try testing.expectEqual(Result.invalid_value, event_set(deep_press_event, .position, &pos));
+}
+
+test "selection gesture deep press without active anchor returns no value" {
+    var terminal: terminal_c.Terminal = null;
+    try testing.expectEqual(Result.success, terminal_c.new(
+        &lib.alloc.test_allocator,
+        &terminal,
+        .{ .cols = 5, .rows = 2, .max_scrollback = 10_000 },
+    ));
+    defer terminal_c.free(terminal);
+
+    var gesture: Gesture = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &gesture,
+    ));
+    defer free(gesture, terminal);
+
+    var deep_press_event: Event = null;
+    try testing.expectEqual(Result.success, event_new(
+        &lib.alloc.test_allocator,
+        &deep_press_event,
+        .deep_press,
+    ));
+    defer event_free(deep_press_event);
+
+    var sel: selection_c.CSelection = undefined;
+    try testing.expectEqual(Result.no_value, handle_event(gesture, terminal, deep_press_event, &sel));
+}
+
+test "selection gesture free null" {
+    free(null, null);
+}
+
+test "selection gesture event free null" {
+    event_free(null);
+}
diff --git a/vendor/libghostty-vt/src/terminal/c/terminal.zig b/vendor/libghostty-vt/src/terminal/c/terminal.zig
index d3293f3b..5a5db2d6 100644
--- a/vendor/libghostty-vt/src/terminal/c/terminal.zig
+++ b/vendor/libghostty-vt/src/terminal/c/terminal.zig
@@ -3,7 +3,7 @@ const testing = std.testing;
 const build_options = @import("terminal_options");
 const lib = @import("../lib.zig");
 const CAllocator = lib.alloc.Allocator;
-const ZigTerminal = @import("../Terminal.zig");
+pub const ZigTerminal = @import("../Terminal.zig");
 const Stream = @import("../stream_terminal.zig").Stream;
 const ScreenSet = @import("../ScreenSet.zig");
 const PageList = @import("../PageList.zig");
@@ -19,6 +19,8 @@ const size_report = @import("../size_report.zig");
 const cell_c = @import("cell.zig");
 const row_c = @import("row.zig");
 const grid_ref_c = @import("grid_ref.zig");
+const grid_ref_tracked_c = @import("grid_ref_tracked.zig");
+const selection_c = @import("selection.zig");
 const style_c = @import("style.zig");
 const color = @import("../color.zig");
 const Result = @import("result.zig").Result;
@@ -34,6 +36,7 @@ const TerminalWrapper = struct {
     terminal: *ZigTerminal,
     stream: Stream,
     effects: Effects = .{},
+    tracked_grid_refs: std.AutoArrayHashMapUnmanaged(*grid_ref_tracked_c.TrackedGridRef, void) = .{},
 };
 
 /// C callback state for terminal effects. Trampolines are always
@@ -208,6 +211,10 @@ const Effects = struct {
 /// C: GhosttyTerminal
 pub const Terminal = ?*TerminalWrapper;
 
+pub fn zigTerminal(terminal_: Terminal) ?*ZigTerminal {
+    return (terminal_ orelse return null).terminal;
+}
+
 /// C: GhosttyTerminalOptions
 pub const Options = extern struct {
     cols: size.CellCountInt,
@@ -259,6 +266,11 @@ fn new_(
     });
     errdefer t.deinit(alloc);
 
+    // libghostty-vt embedders don't necessarily install Ghostty's shell
+    // integration, so don't assume OSC 133 prompts can be redrawn on resize.
+    // Shells can still opt in with OSC 133;A;redraw=1.
+    t.flags.shell_redraws_prompt = .false;
+
     // Setup our stream with trampolines always installed so that
     // setting C callbacks at any time takes effect immediately.
     var handler: Stream.Handler = t.vtHandler();
@@ -313,6 +325,7 @@ pub const Option = enum(c_int) {
     kitty_image_medium_shared_mem = 18,
     apc_max_bytes = 19,
     apc_max_bytes_kitty = 20,
+    selection = 21,
 
     /// Input type expected for setting the option.
     pub fn InType(comptime self: Option) type {
@@ -335,6 +348,7 @@ pub const Option = enum(c_int) {
             .kitty_image_medium_shared_mem,
             => ?*const bool,
             .apc_max_bytes, .apc_max_bytes_kitty => ?*const usize,
+            .selection => ?*const selection_c.CSelection,
         };
     }
 };
@@ -442,6 +456,14 @@ fn setTyped(
                 wrapper.stream.handler.apc_handler.max_bytes.remove(.kitty);
             }
         },
+        .selection => {
+            if (value) |ptr| {
+                const sel = ptr.toZig() orelse return .invalid_value;
+                wrapper.terminal.screens.active.select(sel) catch return .out_of_memory;
+            } else {
+                wrapper.terminal.screens.active.clearSelection();
+            }
+        },
     }
     return .success;
 }
@@ -575,13 +597,15 @@ pub const TerminalData = enum(c_int) {
     kitty_image_medium_temp_file = 28,
     kitty_image_medium_shared_mem = 29,
     kitty_graphics = 30,
+    selection = 31,
+    viewport_active = 32,
 
     /// Output type expected for querying the data of the given kind.
     pub fn OutType(comptime self: TerminalData) type {
         return switch (self) {
             .invalid => void,
             .cols, .rows, .cursor_x, .cursor_y => size.CellCountInt,
-            .cursor_pending_wrap, .cursor_visible, .mouse_tracking => bool,
+            .cursor_pending_wrap, .cursor_visible, .mouse_tracking, .viewport_active => bool,
             .active_screen => TerminalScreen,
             .kitty_keyboard_flags => u8,
             .scrollbar => TerminalScrollbar,
@@ -603,6 +627,7 @@ pub const TerminalData = enum(c_int) {
             .kitty_image_medium_shared_mem,
             => bool,
             .kitty_graphics => KittyGraphics,
+            .selection => selection_c.CSelection,
         };
     }
 };
@@ -712,6 +737,10 @@ fn getTyped(
             if (comptime !build_options.kitty_graphics) return .no_value;
             out.* = &t.screens.active.kitty_images;
         },
+        .selection => out.* = selection_c.CSelection.fromZig(
+            t.screens.active.selection orelse return .no_value,
+        ),
+        .viewport_active => out.* = t.screens.active.pages.viewport == .active,
     }
 
     return .success;
@@ -723,18 +752,56 @@ pub fn grid_ref(
     out_ref: ?*grid_ref_c.CGridRef,
 ) callconv(lib.calling_conv) Result {
     const t: *ZigTerminal = (terminal_ orelse return .invalid_value).terminal;
-    const zig_pt: point.Point = switch (pt.tag) {
-        .active => .{ .active = pt.value.active },
-        .viewport => .{ .viewport = pt.value.viewport },
-        .screen => .{ .screen = pt.value.screen },
-        .history => .{ .history = pt.value.history },
-    };
+    const zig_pt: point.Point = .fromC(pt);
     const p = t.screens.active.pages.pin(zig_pt) orelse
         return .invalid_value;
     if (out_ref) |out| out.* = grid_ref_c.CGridRef.fromPin(p);
     return .success;
 }
 
+pub fn grid_ref_track(
+    terminal_: Terminal,
+    pt: point.Point.C,
+    out_ref: ?*grid_ref_tracked_c.CTrackedGridRef,
+) callconv(lib.calling_conv) Result {
+    const wrapper = terminal_ orelse return .invalid_value;
+    const out = out_ref orelse return .invalid_value;
+    out.* = null;
+
+    const t: *ZigTerminal = wrapper.terminal;
+    const list = &t.screens.active.pages;
+    const p = list.pin(.fromC(pt)) orelse return .invalid_value;
+    const tracked_pin = list.trackPin(p) catch return .out_of_memory;
+
+    const alloc = t.gpa();
+    const ref = alloc.create(grid_ref_tracked_c.TrackedGridRef) catch {
+        list.untrackPin(tracked_pin);
+        return .out_of_memory;
+    };
+    ref.* = .{
+        .alloc = alloc,
+        .terminal = wrapper,
+        .screen_key = t.screens.active_key,
+        .screen_generation = t.screens.generation(t.screens.active_key),
+        .pin = tracked_pin,
+    };
+
+    // Store the tracked ref in the terminal so that when we free
+    // the terminal the tracked ref can be detached safely.
+    wrapper.tracked_grid_refs.putNoClobber(
+        alloc,
+        ref,
+        {},
+    ) catch {
+        list.untrackPin(tracked_pin);
+        alloc.destroy(ref);
+        return .out_of_memory;
+    };
+
+    out.* = ref;
+    return .success;
+}
+
 pub fn point_from_grid_ref(
     terminal_: Terminal,
     ref: *const grid_ref_c.CGridRef,
@@ -752,9 +819,11 @@ pub fn point_from_grid_ref(
 pub fn free(terminal_: Terminal) callconv(lib.calling_conv) void {
     const wrapper = terminal_ orelse return;
     const t = wrapper.terminal;
+    const alloc = t.gpa();
 
+    for (wrapper.tracked_grid_refs.keys()) |ref| ref.terminal = null;
+    wrapper.tracked_grid_refs.deinit(alloc);
     wrapper.stream.deinit();
-    const alloc = t.gpa();
     t.deinit(alloc);
     alloc.destroy(t);
     alloc.destroy(wrapper);
@@ -821,6 +890,10 @@ test "scroll_viewport" {
 
     const zt = t.?.terminal;
 
+    var viewport_active: bool = false;
+    try testing.expectEqual(Result.success, get(t, .viewport_active, @ptrCast(&viewport_active)));
+    try testing.expect(viewport_active);
+
     // Write "hello" on the first line
     vt_write(t, "hello", 5);
 
@@ -835,6 +908,8 @@ test "scroll_viewport" {
 
     // Scroll to top: "hello" should be visible again
     scroll_viewport(t, .{ .tag = .top, .value = undefined });
+    try testing.expectEqual(Result.success, get(t, .viewport_active, @ptrCast(&viewport_active)));
+    try testing.expect(!viewport_active);
     {
         const str = try zt.plainString(testing.allocator);
         defer testing.allocator.free(str);
@@ -843,6 +918,8 @@ test "scroll_viewport" {
 
     // Scroll to bottom: viewport should be empty again
     scroll_viewport(t, .{ .tag = .bottom, .value = undefined });
+    try testing.expectEqual(Result.success, get(t, .viewport_active, @ptrCast(&viewport_active)));
+    try testing.expect(viewport_active);
     {
         const str = try zt.plainString(testing.allocator);
         defer testing.allocator.free(str);
@@ -851,6 +928,8 @@ test "scroll_viewport" {
 
     // Scroll up by delta to bring "hello" back into view
     scroll_viewport(t, .{ .tag = .delta, .value = .{ .delta = -3 } });
+    try testing.expectEqual(Result.success, get(t, .viewport_active, @ptrCast(&viewport_active)));
+    try testing.expect(!viewport_active);
     {
         const str = try zt.plainString(testing.allocator);
         defer testing.allocator.free(str);
@@ -1298,6 +1377,410 @@ test "get invalid" {
     try testing.expectEqual(Result.invalid_value, get(t, .invalid, null));
 }
 
+test "set and get selection" {
+    var t: Terminal = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &t,
+        .{
+            .cols = 80,
+            .rows = 24,
+            .max_scrollback = 0,
+        },
+    ));
+    defer free(t);
+
+    vt_write(t, "Hello", 5);
+
+    var start_ref: grid_ref_c.CGridRef = .{};
+    try testing.expectEqual(Result.success, grid_ref(t, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 0, .y = 0 } },
+    }, &start_ref));
+
+    var end_ref: grid_ref_c.CGridRef = .{};
+    try testing.expectEqual(Result.success, grid_ref(t, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 4, .y = 0 } },
+    }, &end_ref));
+
+    var out: selection_c.CSelection = undefined;
+    try testing.expectEqual(Result.no_value, get(t, .selection, @ptrCast(&out)));
+
+    const sel: selection_c.CSelection = .{
+        .start = start_ref,
+        .end = end_ref,
+        .rectangle = true,
+    };
+    try testing.expectEqual(Result.success, set(t, .selection, @ptrCast(&sel)));
+    try testing.expect(t.?.terminal.screens.active.selection.?.tracked());
+
+    try testing.expectEqual(Result.success, get(t, .selection, @ptrCast(&out)));
+    try testing.expect(out.start.toPin().?.eql(start_ref.toPin().?));
+    try testing.expect(out.end.toPin().?.eql(end_ref.toPin().?));
+    try testing.expect(out.rectangle);
+
+    try testing.expectEqual(Result.success, set(t, .selection, null));
+    try testing.expect(t.?.terminal.screens.active.selection == null);
+    try testing.expectEqual(Result.no_value, get(t, .selection, @ptrCast(&out)));
+}
+
+test "selection derivation helpers" {
+    var t: Terminal = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &t,
+        .{
+            .cols = 80,
+            .rows = 24,
+            .max_scrollback = 0,
+        },
+    ));
+    defer free(t);
+
+    vt_write(t, "  Hello  \r\nWorld", 16);
+
+    var out: selection_c.CSelection = undefined;
+
+    var word_ref: grid_ref_c.CGridRef = .{};
+    try testing.expectEqual(Result.success, grid_ref(t, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 3, .y = 0 } },
+    }, &word_ref));
+
+    var empty_ref: grid_ref_c.CGridRef = .{};
+    try testing.expectEqual(Result.success, grid_ref(t, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 20, .y = 0 } },
+    }, &empty_ref));
+
+    var line_ref: grid_ref_c.CGridRef = .{};
+    try testing.expectEqual(Result.success, grid_ref(t, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 0, .y = 0 } },
+    }, &line_ref));
+
+    var word_opts: selection_c.SelectWordOptions = .{
+        .ref = word_ref,
+    };
+    try testing.expectEqual(Result.success, selection_c.word(t, &word_opts, &out));
+    try testing.expectEqual(@as(u16, 2), out.start.toPin().?.x);
+    try testing.expectEqual(@as(u16, 6), out.end.toPin().?.x);
+
+    word_opts.ref = empty_ref;
+    try testing.expectEqual(Result.no_value, selection_c.word(t, &word_opts, &out));
+
+    var between_start_ref: grid_ref_c.CGridRef = .{};
+    try testing.expectEqual(Result.success, grid_ref(t, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 20, .y = 1 } },
+    }, &between_start_ref));
+
+    var between_end_ref: grid_ref_c.CGridRef = .{};
+    try testing.expectEqual(Result.success, grid_ref(t, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 0, .y = 1 } },
+    }, &between_end_ref));
+
+    var word_between_opts: selection_c.SelectWordBetweenOptions = .{
+        .start = between_start_ref,
+        .end = between_end_ref,
+    };
+    try testing.expectEqual(Result.success, selection_c.word_between(t, &word_between_opts, &out));
+    try testing.expectEqual(@as(u16, 0), out.start.toPin().?.x);
+    try testing.expectEqual(@as(u16, 1), out.start.toPin().?.y);
+    try testing.expectEqual(@as(u16, 4), out.end.toPin().?.x);
+    try testing.expectEqual(@as(u16, 1), out.end.toPin().?.y);
+
+    var line_opts: selection_c.SelectLineOptions = .{
+        .ref = line_ref,
+    };
+    try testing.expectEqual(Result.success, selection_c.line(t, &line_opts, &out));
+    try testing.expectEqual(@as(u16, 2), out.start.toPin().?.x);
+    try testing.expectEqual(@as(u16, 6), out.end.toPin().?.x);
+
+    try testing.expectEqual(Result.success, selection_c.all(t, &out));
+    try testing.expectEqual(@as(u16, 2), out.start.toPin().?.x);
+    try testing.expectEqual(@as(u16, 0), out.start.toPin().?.y);
+    try testing.expectEqual(@as(u16, 4), out.end.toPin().?.x);
+    try testing.expectEqual(@as(u16, 1), out.end.toPin().?.y);
+
+    try testing.expectEqual(Result.no_value, selection_c.output(t, line_ref, &out));
+
+    line_opts.size = @sizeOf(usize) - 1;
+    try testing.expectEqual(Result.invalid_value, selection_c.line(t, &line_opts, &out));
+    try testing.expectEqual(Result.invalid_value, selection_c.word(t, null, &out));
+    try testing.expectEqual(Result.invalid_value, selection_c.word(t, &word_opts, null));
+    try testing.expectEqual(Result.invalid_value, selection_c.word_between(t, null, &out));
+    try testing.expectEqual(Result.invalid_value, selection_c.word_between(t, &word_between_opts, null));
+}
+
+test "selection_adjust mutates snapshot end" {
+    var t: Terminal = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &t,
+        .{
+            .cols = 80,
+            .rows = 24,
+            .max_scrollback = 0,
+        },
+    ));
+    defer free(t);
+
+    vt_write(t, "Hello", 5);
+
+    var start_ref: grid_ref_c.CGridRef = .{};
+    try testing.expectEqual(Result.success, grid_ref(t, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 0, .y = 0 } },
+    }, &start_ref));
+
+    var end_ref: grid_ref_c.CGridRef = .{};
+    try testing.expectEqual(Result.success, grid_ref(t, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 1, .y = 0 } },
+    }, &end_ref));
+
+    var sel: selection_c.CSelection = .{
+        .start = start_ref,
+        .end = end_ref,
+    };
+    try testing.expectEqual(Result.success, selection_c.adjust(t, &sel, .right));
+    try testing.expectEqual(@as(u16, 0), sel.start.toPin().?.x);
+    try testing.expectEqual(@as(u16, 2), sel.end.toPin().?.x);
+
+    try testing.expectEqual(Result.success, selection_c.adjust(t, &sel, .left));
+    try testing.expectEqual(@as(u16, 0), sel.start.toPin().?.x);
+    try testing.expectEqual(@as(u16, 1), sel.end.toPin().?.x);
+
+    sel = .{
+        .start = end_ref,
+        .end = start_ref,
+    };
+    try testing.expectEqual(Result.success, selection_c.adjust(t, &sel, .right));
+    try testing.expectEqual(@as(u16, 1), sel.start.toPin().?.x);
+    try testing.expectEqual(@as(u16, 1), sel.end.toPin().?.x);
+}
+
+test "selection_order and selection_ordered" {
+    var t: Terminal = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &t,
+        .{
+            .cols = 80,
+            .rows = 24,
+            .max_scrollback = 0,
+        },
+    ));
+    defer free(t);
+
+    vt_write(t, "Hello\r\nWorld", 12);
+
+    var start_ref: grid_ref_c.CGridRef = .{};
+    try testing.expectEqual(Result.success, grid_ref(t, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 3, .y = 0 } },
+    }, &start_ref));
+
+    var end_ref: grid_ref_c.CGridRef = .{};
+    try testing.expectEqual(Result.success, grid_ref(t, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 1, .y = 1 } },
+    }, &end_ref));
+
+    const sel: selection_c.CSelection = .{
+        .start = start_ref,
+        .end = end_ref,
+        .rectangle = true,
+    };
+
+    var order: selection_c.Order = undefined;
+    try testing.expectEqual(Result.success, selection_c.order(t, &sel, &order));
+    try testing.expectEqual(selection_c.Order.mirrored_forward, order);
+
+    var out: selection_c.CSelection = undefined;
+    try testing.expectEqual(Result.success, selection_c.ordered(t, &sel, .forward, &out));
+    try testing.expectEqual(@as(u16, 1), out.start.toPin().?.x);
+    try testing.expectEqual(@as(u16, 0), out.start.toPin().?.y);
+    try testing.expectEqual(@as(u16, 3), out.end.toPin().?.x);
+    try testing.expectEqual(@as(u16, 1), out.end.toPin().?.y);
+    try testing.expect(out.rectangle);
+
+    try testing.expectEqual(Result.success, selection_c.ordered(t, &sel, .reverse, &out));
+    try testing.expectEqual(@as(u16, 3), out.start.toPin().?.x);
+    try testing.expectEqual(@as(u16, 1), out.start.toPin().?.y);
+    try testing.expectEqual(@as(u16, 1), out.end.toPin().?.x);
+    try testing.expectEqual(@as(u16, 0), out.end.toPin().?.y);
+    try testing.expect(out.rectangle);
+}
+
+test "selection_contains" {
+    var t: Terminal = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &t,
+        .{
+            .cols = 80,
+            .rows = 24,
+            .max_scrollback = 0,
+        },
+    ));
+    defer free(t);
+
+    vt_write(t, "Hello\r\nWorld", 12);
+
+    var start_ref: grid_ref_c.CGridRef = .{};
+    try testing.expectEqual(Result.success, grid_ref(t, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 3, .y = 0 } },
+    }, &start_ref));
+
+    var end_ref: grid_ref_c.CGridRef = .{};
+    try testing.expectEqual(Result.success, grid_ref(t, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 1, .y = 1 } },
+    }, &end_ref));
+
+    const linear: selection_c.CSelection = .{
+        .start = start_ref,
+        .end = end_ref,
+    };
+
+    var contains: bool = undefined;
+    try testing.expectEqual(Result.success, selection_c.contains(t, &linear, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 4, .y = 0 } },
+    }, &contains));
+    try testing.expect(contains);
+
+    try testing.expectEqual(Result.success, selection_c.contains(t, &linear, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 2, .y = 0 } },
+    }, &contains));
+    try testing.expect(!contains);
+
+    const rectangle: selection_c.CSelection = .{
+        .start = start_ref,
+        .end = end_ref,
+        .rectangle = true,
+    };
+
+    try testing.expectEqual(Result.success, selection_c.contains(t, &rectangle, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 2, .y = 0 } },
+    }, &contains));
+    try testing.expect(contains);
+}
+
+test "selection_equal" {
+    var t: Terminal = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &t,
+        .{
+            .cols = 80,
+            .rows = 24,
+            .max_scrollback = 0,
+        },
+    ));
+    defer free(t);
+
+    var other_t: Terminal = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &other_t,
+        .{
+            .cols = 80,
+            .rows = 24,
+            .max_scrollback = 0,
+        },
+    ));
+    defer free(other_t);
+
+    vt_write(t, "Hello", 5);
+    vt_write(other_t, "Hello", 5);
+
+    var start_ref: grid_ref_c.CGridRef = .{};
+    try testing.expectEqual(Result.success, grid_ref(t, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 0, .y = 0 } },
+    }, &start_ref));
+
+    var end_ref: grid_ref_c.CGridRef = .{};
+    try testing.expectEqual(Result.success, grid_ref(t, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 1, .y = 0 } },
+    }, &end_ref));
+
+    var other_end_ref: grid_ref_c.CGridRef = .{};
+    try testing.expectEqual(Result.success, grid_ref(t, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 2, .y = 0 } },
+    }, &other_end_ref));
+
+    var cross_terminal_ref: grid_ref_c.CGridRef = .{};
+    try testing.expectEqual(Result.success, grid_ref(other_t, .{
+        .tag = .active,
+        .value = .{ .active = .{ .x = 1, .y = 0 } },
+    }, &cross_terminal_ref));
+
+    const sel: selection_c.CSelection = .{
+        .start = start_ref,
+        .end = end_ref,
+    };
+    const equal_sel: selection_c.CSelection = .{
+        .start = start_ref,
+        .end = end_ref,
+    };
+    const different_endpoint: selection_c.CSelection = .{
+        .start = start_ref,
+        .end = other_end_ref,
+    };
+    const different_rectangle: selection_c.CSelection = .{
+        .start = start_ref,
+        .end = end_ref,
+        .rectangle = true,
+    };
+    const cross_terminal: selection_c.CSelection = .{
+        .start = start_ref,
+        .end = cross_terminal_ref,
+    };
+
+    var equal: bool = undefined;
+    try testing.expectEqual(Result.success, selection_c.equal(t, &sel, &equal_sel, &equal));
+    try testing.expect(equal);
+
+    try testing.expectEqual(Result.success, selection_c.equal(t, &sel, &different_endpoint, &equal));
+    try testing.expect(!equal);
+
+    try testing.expectEqual(Result.success, selection_c.equal(t, &sel, &different_rectangle, &equal));
+    try testing.expect(!equal);
+
+    try testing.expectEqual(Result.success, selection_c.equal(t, &sel, &cross_terminal, &equal));
+    try testing.expect(!equal);
+    try testing.expectEqual(Result.invalid_value, selection_c.equal(t, &sel, &equal_sel, null));
+}
+
+test "selection_order invalid values" {
+    var t: Terminal = null;
+    try testing.expectEqual(Result.success, new(
+        &lib.alloc.test_allocator,
+        &t,
+        .{
+            .cols = 80,
+            .rows = 24,
+            .max_scrollback = 0,
+        },
+    ));
+    defer free(t);
+
+    var order: selection_c.Order = undefined;
+    try testing.expectEqual(Result.invalid_value, selection_c.order(null, null, &order));
+    try testing.expectEqual(Result.invalid_value, selection_c.order(t, null, &order));
+}
+
 test "grid_ref" {
     var t: Terminal = null;
     try testing.expectEqual(Result.success, new(
diff --git a/vendor/libghostty-vt/src/terminal/c/types.zig b/vendor/libghostty-vt/src/terminal/c/types.zig
index 500809d9..de043a03 100644
--- a/vendor/libghostty-vt/src/terminal/c/types.zig
+++ b/vendor/libghostty-vt/src/terminal/c/types.zig
@@ -14,36 +14,60 @@ const size_report = @import("size_report.zig");
 const terminal = @import("terminal.zig");
 const formatter = @import("formatter.zig");
 const selection = @import("selection.zig");
+const selection_gesture = @import("selection_gesture.zig");
 const render = @import("render.zig");
 const style_c = @import("style.zig");
 const mouse_encode = @import("mouse_encode.zig");
 const grid_ref = @import("grid_ref.zig");
 
+/// C: GhosttySurfacePosition
+pub const SurfacePosition = extern struct {
+    x: f64,
+    y: f64,
+};
+
+/// C: GhosttyCodepoints
+pub const Codepoints = extern struct {
+    ptr: ?[*]const u32 = null,
+    len: usize = 0,
+};
+
 /// All C API structs and their Ghostty C names.
-pub const structs: std.StaticStringMap(StructInfo) = .initComptime(.{
-    .{ "GhosttyColorRgb", StructInfo.init(color.RGB.C) },
-    .{ "GhosttyDeviceAttributes", StructInfo.init(terminal.DeviceAttributes) },
-    .{ "GhosttyDeviceAttributesPrimary", StructInfo.init(terminal.DeviceAttributes.Primary) },
-    .{ "GhosttyDeviceAttributesSecondary", StructInfo.init(terminal.DeviceAttributes.Secondary) },
-    .{ "GhosttyDeviceAttributesTertiary", StructInfo.init(terminal.DeviceAttributes.Tertiary) },
-    .{ "GhosttyFormatterTerminalOptions", StructInfo.init(formatter.TerminalOptions) },
-    .{ "GhosttySelection", StructInfo.init(selection.CSelection) },
-    .{ "GhosttyFormatterTerminalExtra", StructInfo.init(formatter.TerminalOptions.Extra) },
-    .{ "GhosttyFormatterScreenExtra", StructInfo.init(formatter.ScreenOptions.Extra) },
-    .{ "GhosttyGridRef", StructInfo.init(grid_ref.CGridRef) },
-    .{ "GhosttyMouseEncoderSize", StructInfo.init(mouse_encode.Size) },
-    .{ "GhosttyMousePosition", StructInfo.init(mouse_event.Position) },
-    .{ "GhosttyPoint", StructInfo.init(point.Point.C) },
-    .{ "GhosttyPointCoordinate", StructInfo.init(point.Coordinate) },
-    .{ "GhosttyRenderStateColors", StructInfo.init(render.Colors) },
-    .{ "GhosttySizeReportSize", StructInfo.init(size_report.Size) },
-    .{ "GhosttyString", StructInfo.init(lib.String) },
-    .{ "GhosttyStyle", StructInfo.init(style_c.Style) },
-    .{ "GhosttyStyleColor", StructInfo.init(style_c.Color) },
-    .{ "GhosttyTerminalOptions", StructInfo.init(terminal.Options) },
-    .{ "GhosttyTerminalScrollbar", StructInfo.init(terminal.TerminalScrollbar) },
-    .{ "GhosttyTerminalScrollViewport", StructInfo.init(terminal.ScrollViewport) },
-});
+pub const structs: std.StaticStringMap(StructInfo) = structs: {
+    @setEvalBranchQuota(10_000);
+    break :structs .initComptime(.{
+        .{ "GhosttyBuffer", StructInfo.init(lib.Buffer) },
+        .{ "GhosttyCodepoints", StructInfo.init(Codepoints) },
+        .{ "GhosttyColorRgb", StructInfo.init(color.RGB.C) },
+        .{ "GhosttyDeviceAttributes", StructInfo.init(terminal.DeviceAttributes) },
+        .{ "GhosttyDeviceAttributesPrimary", StructInfo.init(terminal.DeviceAttributes.Primary) },
+        .{ "GhosttyDeviceAttributesSecondary", StructInfo.init(terminal.DeviceAttributes.Secondary) },
+        .{ "GhosttyDeviceAttributesTertiary", StructInfo.init(terminal.DeviceAttributes.Tertiary) },
+        .{ "GhosttyFormatterTerminalOptions", StructInfo.init(formatter.TerminalOptions) },
+        .{ "GhosttySelection", StructInfo.init(selection.CSelection) },
+        .{ "GhosttyTerminalSelectWordOptions", StructInfo.init(selection.SelectWordOptions) },
+        .{ "GhosttyTerminalSelectWordBetweenOptions", StructInfo.init(selection.SelectWordBetweenOptions) },
+        .{ "GhosttyTerminalSelectLineOptions", StructInfo.init(selection.SelectLineOptions) },
+        .{ "GhosttyFormatterTerminalExtra", StructInfo.init(formatter.TerminalOptions.Extra) },
+        .{ "GhosttyFormatterScreenExtra", StructInfo.init(formatter.ScreenOptions.Extra) },
+        .{ "GhosttyGridRef", StructInfo.init(grid_ref.CGridRef) },
+        .{ "GhosttyMouseEncoderSize", StructInfo.init(mouse_encode.Size) },
+        .{ "GhosttyMousePosition", StructInfo.init(mouse_event.Position) },
+        .{ "GhosttyPoint", StructInfo.init(point.Point.C) },
+        .{ "GhosttyPointCoordinate", StructInfo.init(point.Coordinate) },
+        .{ "GhosttyRenderStateColors", StructInfo.init(render.Colors) },
+        .{ "GhosttySelectionGestureBehaviors", StructInfo.init(selection_gesture.Behaviors) },
+        .{ "GhosttySelectionGestureGeometry", StructInfo.init(selection_gesture.Geometry) },
+        .{ "GhosttySizeReportSize", StructInfo.init(size_report.Size) },
+        .{ "GhosttyString", StructInfo.init(lib.String) },
+        .{ "GhosttySurfacePosition", StructInfo.init(SurfacePosition) },
+        .{ "GhosttyStyle", StructInfo.init(style_c.Style) },
+        .{ "GhosttyStyleColor", StructInfo.init(style_c.Color) },
+        .{ "GhosttyTerminalOptions", StructInfo.init(terminal.Options) },
+        .{ "GhosttyTerminalScrollbar", StructInfo.init(terminal.TerminalScrollbar) },
+        .{ "GhosttyTerminalScrollViewport", StructInfo.init(terminal.ScrollViewport) },
+    });
+};
 
 /// The comptime-generated JSON string of all structs.
 pub const json: [:0]const u8 = json: {
@@ -144,6 +168,11 @@ fn jsonWriteAll(writer: *std.Io.Writer) std.Io.Writer.Error!void {
 fn typeName(comptime T: type) []const u8 {
     return switch (@typeInfo(T)) {
         .bool => "bool",
+        .float => |info| switch (info.bits) {
+            32 => "f32",
+            64 => "f64",
+            else => @compileError("unsupported float size"),
+        },
         .int => |info| switch (info.signedness) {
             .signed => switch (info.bits) {
                 8 => "i8",
diff --git a/vendor/libghostty-vt/src/terminal/lib.zig b/vendor/libghostty-vt/src/terminal/lib.zig
index 3cd657b4..921d831b 100644
--- a/vendor/libghostty-vt/src/terminal/lib.zig
+++ b/vendor/libghostty-vt/src/terminal/lib.zig
@@ -14,6 +14,7 @@ pub const calling_conv: std.builtin.CallingConvention = .c;
 
 /// Forwarded decls from lib that are used.
 pub const alloc = lib.allocator;
+pub const Buffer = lib.Buffer;
 pub const Enum = lib.Enum;
 pub const TaggedUnion = lib.TaggedUnion;
 pub const Struct = lib.Struct;
diff --git a/vendor/libghostty-vt/src/terminal/main.zig b/vendor/libghostty-vt/src/terminal/main.zig
index 87a9aded..53491a00 100644
--- a/vendor/libghostty-vt/src/terminal/main.zig
+++ b/vendor/libghostty-vt/src/terminal/main.zig
@@ -49,6 +49,7 @@ pub const Screen = @import("Screen.zig");
 pub const ScreenSet = @import("ScreenSet.zig");
 pub const Scrollbar = PageList.Scrollbar;
 pub const Selection = @import("Selection.zig");
+pub const SelectionGesture = @import("SelectionGesture.zig");
 pub const SizeReportStyle = csi.SizeReportStyle;
 pub const StringMap = @import("StringMap.zig");
 pub const Style = style.Style;
diff --git a/vendor/libghostty-vt/src/terminal/point.zig b/vendor/libghostty-vt/src/terminal/point.zig
index 4297bf5b..f6bf25c3 100644
--- a/vendor/libghostty-vt/src/terminal/point.zig
+++ b/vendor/libghostty-vt/src/terminal/point.zig
@@ -76,6 +76,16 @@ pub const Point = union(Tag) {
     pub const C = c_union.C;
     pub const CValue = c_union.CValue;
     pub const cval = c_union.cval;
+
+    /// Convert a C ABI point into the native Zig tagged union.
+    pub fn fromC(pt: C) Point {
+        return switch (pt.tag) {
+            .active => .{ .active = pt.value.active },
+            .viewport => .{ .viewport = pt.value.viewport },
+            .screen => .{ .screen = pt.value.screen },
+            .history => .{ .history = pt.value.history },
+        };
+    }
 };
 
 pub const Coordinate = extern struct {
diff --git a/vendor/libghostty-vt/src/terminal/selection_codepoints.zig b/vendor/libghostty-vt/src/terminal/selection_codepoints.zig
new file mode 100644
index 00000000..4c318403
--- /dev/null
+++ b/vendor/libghostty-vt/src/terminal/selection_codepoints.zig
@@ -0,0 +1,31 @@
+// This file contains various default word boundaries used for
+// selection logic. We put it in a separate file so that different
+// subsystems can import it without introducing a number of
+// dependencies.
+
+/// Default boundary characters for word selection: ` \t'"│`|:;,()[]{}<>$`
+pub const default_word_boundaries = [_]u21{
+    0, // null
+    ' ', // space
+    '\t', // tab
+    '\'', // single quote
+    '"', // double quote
+    '│', // U+2502 box drawing
+    '`', // backtick
+    '|', // pipe
+    ':', // colon
+    ';', // semicolon
+    ',', // comma
+    '(', // left paren
+    ')', // right paren
+    '[', // left bracket
+    ']', // right bracket
+    '{', // left brace
+    '}', // right brace
+    '<', // less than
+    '>', // greater than
+    '$', // dollar
+};
+
+/// Default whitespace characters trimmed from line selections.
+pub const default_line_whitespace = [_]u21{ 0, ' ', '\t' };