From 53add253b604cd75ab1574a891d6b31e66b2233d Mon Sep 17 00:00:00 2001
From: K Simmons <keith@zed.dev>
Date: Thu, 21 Jul 2022 22:23:56 -0700
Subject: [PATCH] wip new mouse region events

---
 crates/gpui/src/scene/mouse_region.rs | 17 +++++++++++++++++
 crates/workspace/src/pane.rs          | 13 +++++++++++++
 2 files changed, 30 insertions(+)

diff --git a/crates/gpui/src/scene/mouse_region.rs b/crates/gpui/src/scene/mouse_region.rs
index 704567450a..01bb9fde69 100644
--- a/crates/gpui/src/scene/mouse_region.rs
+++ b/crates/gpui/src/scene/mouse_region.rs
@@ -273,10 +273,12 @@ impl HandlerSet {
 pub enum MouseRegionEvent {
     Move(MouseMovedEvent),
     Drag(Vector2F, MouseMovedEvent),
+    DragOver(Vector2F, MouseMovedEvent),
     Hover(bool, MouseMovedEvent),
     Down(MouseButtonEvent),
     Up(MouseButtonEvent),
     Click(MouseButtonEvent),
+    UpOut(MouseButtonEvent),
     DownOut(MouseButtonEvent),
     ScrollWheel(ScrollWheelEvent),
 }
@@ -291,6 +293,12 @@ impl MouseRegionEvent {
             Default::default(),
         ))
     }
+    pub fn drag_over_disc() -> Discriminant<MouseRegionEvent> {
+        std::mem::discriminant(&MouseRegionEvent::DragOver(
+            Default::default(),
+            Default::default(),
+        ))
+    }
     pub fn hover_disc() -> Discriminant<MouseRegionEvent> {
         std::mem::discriminant(&MouseRegionEvent::Hover(
             Default::default(),
@@ -303,6 +311,9 @@ impl MouseRegionEvent {
     pub fn up_disc() -> Discriminant<MouseRegionEvent> {
         std::mem::discriminant(&MouseRegionEvent::Up(Default::default()))
     }
+    pub fn up_out_disc() -> Discriminant<MouseRegionEvent> {
+        std::mem::discriminant(&MouseRegionEvent::UpOut(Default::default()))
+    }
     pub fn click_disc() -> Discriminant<MouseRegionEvent> {
         std::mem::discriminant(&MouseRegionEvent::Click(Default::default()))
     }
@@ -319,6 +330,9 @@ impl MouseRegionEvent {
             MouseRegionEvent::Drag(_, MouseMovedEvent { pressed_button, .. }) => {
                 (Self::drag_disc(), *pressed_button)
             }
+            MouseRegionEvent::DragOver(_, MouseMovedEvent { pressed_button, .. }) => {
+                (Self::drag_over_disc(), *pressed_button)
+            }
             MouseRegionEvent::Hover(_, _) => (Self::hover_disc(), None),
             MouseRegionEvent::Down(MouseButtonEvent { button, .. }) => {
                 (Self::down_disc(), Some(*button))
@@ -329,6 +343,9 @@ impl MouseRegionEvent {
             MouseRegionEvent::Click(MouseButtonEvent { button, .. }) => {
                 (Self::click_disc(), Some(*button))
             }
+            MouseRegionEvent::UpOut(MouseButtonEvent { button, .. }) => {
+                (Self::up_out_disc(), Some(*button))
+            }
             MouseRegionEvent::DownOut(MouseButtonEvent { button, .. }) => {
                 (Self::down_out_disc(), Some(*button))
             }
diff --git a/crates/workspace/src/pane.rs b/crates/workspace/src/pane.rs
index 34108eef5e..eb21c2ac83 100644
--- a/crates/workspace/src/pane.rs
+++ b/crates/workspace/src/pane.rs
@@ -1022,6 +1022,19 @@ impl Pane {
                         cx.dispatch_action(ActivateItem(ix));
                     })
                     .on_click(MouseButton::Middle, close_tab_callback)
+                    .on_drag(MouseButton::Left, |_, cx| {
+                        cx.global::<DragAndDrop>().dragging(some view handle)
+                    })
+                    .on_mouse_up_out(MouseButton::Left, |_, cx| {
+                        cx.global::<DragAndDrop>().stopped_dragging(some view handle)
+                    })
+                    .on_drag_over(MouseButton::Left, |started, _, cx| {
+                        if started {
+                            if let Some(tab) = cx.global::<DragAndDrop>().current_dragged::<Tab>() {
+                                cx.dispatch_action(ReceivingTab)
+                            }
+                        }
+                    })
                     .boxed()
                 })
             }