fix: forward any-motion pane mouse events

refs #419

2 files changed, 91 insertions, 2 deletions

diff --git a/src/pane/input.rs b/src/pane/input.rs
index 262e036d..6906e77d 100644
--- a/src/pane/input.rs
+++ b/src/pane/input.rs
@@ -58,6 +58,14 @@ pub(super) fn ghostty_mouse_encoder_for_terminal(
 ) -> Option<crate::ghostty::MouseEncoder> {
     let mut encoder = crate::ghostty::MouseEncoder::new().ok()?;
     encoder.set_from_terminal(terminal);
+    if terminal
+        .mode_get(crate::ghostty::MODE_MOUSE_SGR_PIXELS)
+        .ok()?
+    {
+        // Herdr receives host mouse positions in terminal cells. Downgrade
+        // SGR-pixels to normal SGR so forwarded coordinates stay cell-local.
+        encoder.set_format(crate::ghostty::MOUSE_FORMAT_SGR);
+    }
     let cols = terminal.cols().ok()? as u32;
     let rows = terminal.rows().ok()? as u32;
     encoder.set_size(cols, rows, 1, 1);
@@ -121,6 +129,24 @@ pub(super) fn ghostty_mouse_event_from_button_kind(
     Some(event)
 }
 
+pub(super) fn ghostty_mouse_event_from_motion_kind(
+    kind: crossterm::event::MouseEventKind,
+    column: u16,
+    row: u16,
+    modifiers: crossterm::event::KeyModifiers,
+) -> Option<crate::ghostty::MouseEvent> {
+    if kind != crossterm::event::MouseEventKind::Moved {
+        return None;
+    }
+
+    let mut event = crate::ghostty::MouseEvent::new().ok()?;
+    event.set_action(crate::ghostty::MOUSE_ACTION_MOTION);
+    event.clear_button();
+    event.set_mods(ghostty_mods_from_key_modifiers(modifiers));
+    event.set_position(column as f32, row as f32);
+    Some(event)
+}
+
 pub(super) fn ghostty_mouse_event_from_wheel_kind(
     kind: crossterm::event::MouseEventKind,
     column: u16,
diff --git a/src/pane/terminal.rs b/src/pane/terminal.rs
index be1200e6..0a67f11a 100644
--- a/src/pane/terminal.rs
+++ b/src/pane/terminal.rs
@@ -16,8 +16,8 @@ use crate::protocol::CellData;
 use super::{
     input::{
         ghostty_key_event_from_terminal_key, ghostty_mouse_encoder_for_terminal,
-        ghostty_mouse_event_from_button_kind, ghostty_mouse_event_from_wheel_kind,
-        ghostty_prefers_herdr_text_encoding,
+        ghostty_mouse_event_from_button_kind, ghostty_mouse_event_from_motion_kind,
+        ghostty_mouse_event_from_wheel_kind, ghostty_prefers_herdr_text_encoding,
     },
     kitty_keyboard::KittyKeyboardTracker,
     osc::{
@@ -283,6 +283,17 @@ impl PaneTerminal {
             .encode_mouse_button(kind, column, row, modifiers)
     }
 
+    pub fn encode_mouse_motion(
+        &self,
+        kind: crossterm::event::MouseEventKind,
+        column: u16,
+        row: u16,
+        modifiers: crossterm::event::KeyModifiers,
+    ) -> Option<Vec<u8>> {
+        self.ghostty
+            .encode_mouse_motion(kind, column, row, modifiers)
+    }
+
     pub fn encode_mouse_wheel(
         &self,
         kind: crossterm::event::MouseEventKind,
@@ -887,6 +898,24 @@ impl GhosttyPaneTerminal {
         encoder.encode(&event).ok()
     }
 
+    pub fn encode_mouse_motion(
+        &self,
+        kind: crossterm::event::MouseEventKind,
+        column: u16,
+        row: u16,
+        modifiers: crossterm::event::KeyModifiers,
+    ) -> Option<Vec<u8>> {
+        let Ok(core) = self.core.lock() else {
+            return None;
+        };
+        if !core.terminal.mode_get(MODE_MOUSE_ANY_MOTION).ok()? {
+            return None;
+        }
+        let mut encoder = ghostty_mouse_encoder_for_terminal(&core.terminal)?;
+        let event = ghostty_mouse_event_from_motion_kind(kind, column, row, modifiers)?;
+        encoder.encode(&event).ok()
+    }
+
     pub fn encode_mouse_wheel(
         &self,
         kind: crossterm::event::MouseEventKind,
@@ -2351,6 +2380,40 @@ mod tests {
     }
 
     #[test]
+    fn ghostty_mouse_moved_encoding_uses_any_motion_state() {
+        let (tx, _rx) = mpsc::channel(4);
+        let mut terminal = crate::ghostty::Terminal::new(80, 24, 0).unwrap();
+        terminal.write(b"\x1b[?1003h\x1b[?1006h");
+        let pane = GhosttyPaneTerminal::new(terminal, tx).unwrap();
+
+        let encoded = pane.encode_mouse_motion(
+            crossterm::event::MouseEventKind::Moved,
+            4,
+            6,
+            crossterm::event::KeyModifiers::empty(),
+        );
+
+        assert_eq!(encoded.as_deref(), Some(&b"\x1b[<35;5;7M"[..]));
+    }
+
+    #[test]
+    fn ghostty_mouse_sgr_pixels_downgrades_to_cell_coordinates() {
+        let (tx, _rx) = mpsc::channel(4);
+        let mut terminal = crate::ghostty::Terminal::new(80, 24, 0).unwrap();
+        terminal.write(b"\x1b[?1003h\x1b[?1006h\x1b[?1016h");
+        let pane = GhosttyPaneTerminal::new(terminal, tx).unwrap();
+
+        let encoded = pane.encode_mouse_motion(
+            crossterm::event::MouseEventKind::Moved,
+            4,
+            6,
+            crossterm::event::KeyModifiers::empty(),
+        );
+
+        assert_eq!(encoded.as_deref(), Some(&b"\x1b[<35;5;7M"[..]));
+    }
+
+    #[test]
     fn ghostty_normalize_buffer_symbol_prefers_grapheme_width_when_metadata_disagrees() {
         const WIDE_GRAPHEME: &str = "🙂";
         const VS16_GRAPHEME: &str = "⚠️";