feat: support bottom tab bar placement (#2118)

* feat: support bottom tab bar placement

* fix: preserve mouse cleanup under bottom mode bar

refs #2117

3 files changed, 82 insertions, 2 deletions

diff --git a/src/app/input/mouse.rs b/src/app/input/mouse.rs
index 56b9b676..2c32c95a 100644
--- a/src/app/input/mouse.rs
+++ b/src/app/input/mouse.rs
@@ -483,6 +483,10 @@ impl AppState {
                     }
                 }
 
+                if self.mode_bar_covers_tab_row(mouse.column, mouse.row) {
+                    return None;
+                }
+
                 if self.on_tab_scroll_left_button(mouse.column, mouse.row) {
                     self.scroll_tabs_left();
                     return None;
@@ -913,6 +917,9 @@ impl AppState {
             }
 
             MouseEventKind::ScrollUp | MouseEventKind::ScrollDown
+                if self.mode_bar_covers_tab_row(mouse.column, mouse.row) => {}
+
+            MouseEventKind::ScrollUp | MouseEventKind::ScrollDown
                 if self.on_tab_bar(mouse.column, mouse.row) =>
             {
                 match mouse.kind {
@@ -1063,7 +1070,8 @@ impl AppState {
             }
 
             MouseEventKind::Down(MouseButton::Right)
-                if self.tab_at(mouse.column, mouse.row).is_some() =>
+                if !self.mode_bar_covers_tab_row(mouse.column, mouse.row)
+                    && self.tab_at(mouse.column, mouse.row).is_some() =>
             {
                 if let (Some(ws_idx), Some(tab_idx)) =
                     (self.active, self.tab_at(mouse.column, mouse.row))
@@ -1272,6 +1280,15 @@ impl AppState {
             })
     }
 
+    fn mode_bar_covers_tab_row(&self, col: u16, row: u16) -> bool {
+        self.tab_bar_position == crate::config::TabBarPositionConfig::Bottom
+            && matches!(
+                self.mode,
+                Mode::Navigate | Mode::Prefix | Mode::Copy | Mode::Resize
+            )
+            && self.on_tab_bar(col, row)
+    }
+
     pub(super) fn on_tab_bar(&self, col: u16, row: u16) -> bool {
         let area = self.view.tab_bar_rect;
         area.width > 0
@@ -3393,6 +3410,63 @@ mod tests {
     }
 
     #[test]
+    fn bottom_mode_bar_consumes_hidden_tab_mouse_actions() {
+        let mut app = app_for_mouse_test();
+        let mut ws = Workspace::test_new("one");
+        ws.test_add_tab(Some("two"));
+        app.state.workspaces = vec![ws];
+        app.state.active = Some(0);
+        app.state.selected = 0;
+        app.state.mode = Mode::Prefix;
+        app.state.tab_bar_position = crate::config::TabBarPositionConfig::Bottom;
+
+        crate::ui::compute_view(&mut app.state, Rect::new(0, 0, 106, 20));
+        let second_tab = app.state.view.tab_hit_areas[1];
+        let new_tab = app.state.view.new_tab_hit_area;
+
+        app.handle_mouse(mouse(
+            MouseEventKind::Down(MouseButton::Left),
+            second_tab.x,
+            second_tab.y,
+        ));
+        app.handle_mouse(mouse(
+            MouseEventKind::Up(MouseButton::Left),
+            second_tab.x,
+            second_tab.y,
+        ));
+        app.handle_mouse(mouse(
+            MouseEventKind::ScrollDown,
+            second_tab.x,
+            second_tab.y,
+        ));
+        app.handle_mouse(mouse(
+            MouseEventKind::Down(MouseButton::Right),
+            second_tab.x,
+            second_tab.y,
+        ));
+        app.handle_mouse(mouse(
+            MouseEventKind::Down(MouseButton::Left),
+            new_tab.x,
+            new_tab.y,
+        ));
+
+        app.state.drag = Some(DragState {
+            target: DragTarget::SidebarDivider,
+        });
+        app.handle_mouse(mouse(
+            MouseEventKind::Up(MouseButton::Left),
+            second_tab.x,
+            second_tab.y,
+        ));
+
+        assert_eq!(app.state.workspaces[0].active_tab, 0);
+        assert_eq!(app.state.workspaces[0].tabs.len(), 2);
+        assert!(app.state.context_menu.is_none());
+        assert!(app.state.tab_press.is_none());
+        assert!(app.state.drag.is_none());
+    }
+
+    #[test]
     fn right_click_inactive_tab_opens_menu_without_switching_tabs() {
         let mut app = app_for_mouse_test();
         let mut ws = Workspace::test_new("one");
diff --git a/src/app/mod.rs b/src/app/mod.rs
index 2530a05b..f4bc5008 100644
--- a/src/app/mod.rs
+++ b/src/app/mod.rs
@@ -642,6 +642,7 @@ impl App {
             pane_gaps: config.ui.pane_gaps,
             show_agent_labels_on_pane_borders: config.ui.show_agent_labels_on_pane_borders,
             hide_tab_bar_when_single_tab: config.ui.hide_tab_bar_when_single_tab,
+            tab_bar_position: config.ui.tab_bar_position,
             pane_history_persistence: config.experimental.pane_history,
             reveal_hidden_cursor_for_cjk_ime: config.experimental.reveal_hidden_cursor_for_cjk_ime,
             cjk_ime_agent_filter_configured: !config.experimental.cjk_ime_agents.is_empty(),
@@ -1450,6 +1451,7 @@ impl App {
                 self.state.show_agent_labels_on_pane_borders =
                     config.ui.show_agent_labels_on_pane_borders;
                 self.state.hide_tab_bar_when_single_tab = config.ui.hide_tab_bar_when_single_tab;
+                self.state.tab_bar_position = config.ui.tab_bar_position;
                 self.state.agent_panel_sort =
                     agent_panel_sort_from_config(config.ui.agent_panel_sort);
                 self.state.sidebar_agents = config.ui.sidebar.agents.clone();
diff --git a/src/app/state.rs b/src/app/state.rs
index a1c5afc1..975144b4 100644
--- a/src/app/state.rs
+++ b/src/app/state.rs
@@ -1,4 +1,6 @@
-use crate::config::{Keybinds, NewTerminalCwdConfig, SoundConfig, ToastConfig, ToastDelivery};
+use crate::config::{
+    Keybinds, NewTerminalCwdConfig, SoundConfig, TabBarPositionConfig, ToastConfig, ToastDelivery,
+};
 use crossterm::event::{KeyCode, KeyModifiers};
 use ratatui::layout::{Direction, Rect};
 use ratatui::style::Color;
@@ -1525,6 +1527,7 @@ pub struct AppState {
     pub pane_gaps: bool,
     pub show_agent_labels_on_pane_borders: bool,
     pub hide_tab_bar_when_single_tab: bool,
+    pub tab_bar_position: TabBarPositionConfig,
     pub pane_history_persistence: bool,
     /// Expose the focused pane's cursor anchor to the outer terminal even when
     /// the pane requested `?25l`. See `[experimental] reveal_hidden_cursor_for_cjk_ime`.
@@ -1899,6 +1902,7 @@ impl AppState {
             pane_gaps: false,
             show_agent_labels_on_pane_borders: false,
             hide_tab_bar_when_single_tab: false,
+            tab_bar_position: TabBarPositionConfig::Top,
             pane_history_persistence: false,
             reveal_hidden_cursor_for_cjk_ime: false,
             cjk_ime_agent_filter_configured: false,