Open a MIDI clip in the MIDI Editor by double-clicking it with the Grabber

Double-clicking a MIDI clip in the Edit window only selected it, so the
MIDI Editor had to be opened from Window › MIDI Editor or the dock tabs.
In Pro Tools a Grabber double-click on a MIDI clip opens it in a MIDI
Editor (the "Double-Clicking a MIDI Clip Opens" MIDI preference, which
defaults to an editor); SoundCraft has one, docked, editor.

- A double-click with the Grabber on a MIDI or instrument clip selects
  the clip, as before, and opens the docked MIDI Editor on it. An editor
  that's already open stays open and switches to the clip.
- The Smart Tool follows its zones: its lower half is the Grabber and
  opens the editor; its upper half is the Selector, where a double-click
  still only selects the clip, as in Pro Tools.
- Audio clips are unchanged: a double-click selects them.

Tests: a Grabber double-click opens the editor on the clip; with the
Smart Tool, the upper half selects without opening it and the lower half
opens it; an audio clip leaves the editor closed. The first two fail on
main.

crates/ui-egui/src/edit_window.rs

@@ -1650,6 +1650,9 @@ fn lane_interaction(app: &mut SoundApp, ui: &mut Ui, track: &Track, lane: Rect,
         && let Some(c) = &hit
     {
         let _ = app.run("edit.select", json!({"clips": [c.id.0]}));
+        if eff == Tool::Grabber && matches!(c.content, ClipContent::Midi { .. }) {
+            app.ui.show_midi_editor = true;
+        }
     }
 }
 

crates/ui-egui/tests/midi_double_click.rs

@@ -0,0 +1,93 @@
+//! Double-clicking a MIDI clip with the Grabber opens it in the MIDI Editor, as in Pro Tools.
+
+use egui::{Event, Modifiers, PointerButton, Pos2, RawInput, Rect, pos2, vec2};
+use serde_json::json;
+use soundcraft_engine::model::ClipId;
+use soundcraft_ui_egui::{Services, SoundApp, edit_window, midi_editor};
+
+struct Rig {
+    ctx: egui::Context,
+    app: SoundApp,
+}
+
+impl Rig {
+    fn new(tool: &str) -> Rig {
+        let mut app = SoundApp::new(soundcraft_engine::demo::demo_engine(), None, Services::default());
+        app.engine.execute("edit.tool", &json!({"tool": tool})).unwrap();
+        let mut r = Rig { ctx: egui::Context::default(), app };
+        for _ in 0..4 {
+            r.frame(vec![]);
+        }
+        r
+    }
+
+    fn frame(&mut self, events: Vec<Event>) {
+        let raw = RawInput { screen_rect: Some(Rect::from_min_size(Pos2::ZERO, vec2(1600.0, 1000.0))), events, ..Default::default() };
+        self.ctx
+            .run_ui(raw, |ui| {
+                self.app.logic(ui.ctx());
+                self.app.ui(ui);
+            })
+            .textures_delta
+            .clear();
+    }
+
+    /// The first clip on `track` and its rectangle on screen.
+    fn clip(&self, track: &str) -> (ClipId, Rect) {
+        let s = self.app.engine.session();
+        let t = s.track_by_name(track).unwrap();
+        let c = &t.clips()[0];
+        let tl = edit_window::rect(self.app.edit_layout.timeline);
+        let row = self.app.edit_layout.rows.iter().find(|(id, _)| *id == t.id.0).unwrap().1;
+        let x0 = edit_window::x_of(s, tl, c.start).max(tl.min.x);
+        let x1 = edit_window::x_of(s, tl, c.end()).min(tl.max.x);
+        (c.id, Rect::from_min_max(pos2(x0, row[1]), pos2(x1, row[1] + t.height.points())))
+    }
+
+    fn double_click(&mut self, at: Pos2) {
+        // A second of frames first: egui counts a click within 0.6 s of the one before last as a triple-click.
+        for _ in 0..60 {
+            self.frame(vec![]);
+        }
+        for pressed in [true, false, true, false] {
+            self.frame(vec![
+                Event::PointerMoved(at),
+                Event::PointerButton { pos: at, button: PointerButton::Primary, pressed, modifiers: Modifiers::NONE },
+            ]);
+        }
+        self.frame(vec![]);
+    }
+
+    fn editing(&self) -> Option<ClipId> {
+        self.app.ui.show_midi_editor.then(|| midi_editor::target_clip(&self.app)).flatten()
+    }
+}
+
+#[test]
+fn double_clicking_a_midi_clip_with_the_grabber_opens_the_midi_editor() {
+    let mut r = Rig::new("grabber");
+    let (keys, at) = r.clip("Keys");
+    assert_eq!(r.editing(), None);
+    r.double_click(at.center());
+    assert_eq!(r.editing(), Some(keys));
+}
+
+#[test]
+fn the_smart_tool_opens_it_from_the_lower_half_and_selects_from_the_upper_half() {
+    let mut r = Rig::new("smart");
+    let (keys, at) = r.clip("Keys");
+    r.double_click(pos2(at.center().x, at.top() + at.height() * 0.25));
+    assert!(!r.app.ui.show_midi_editor);
+    assert_eq!(r.app.engine.session().edit.selected_clips, vec![keys]);
+    r.double_click(pos2(at.center().x, at.top() + at.height() * 0.75));
+    assert_eq!(r.editing(), Some(keys));
+}
+
+#[test]
+fn double_clicking_an_audio_clip_leaves_the_midi_editor_closed() {
+    let mut r = Rig::new("grabber");
+    let (kick, at) = r.clip("Kick");
+    r.double_click(at.center());
+    assert!(!r.app.ui.show_midi_editor);
+    assert_eq!(r.app.engine.session().edit.selected_clips, vec![kick]);
+}