From b0232ca225256e8543116c289bcd60ef54ee28cb Mon Sep 17 00:00:00 2001
From: Ryan McGrath <ryan@rymc.io>
Date: Wed, 25 Mar 2020 19:57:47 -0700
Subject: [PATCH] Window movement delegate callback support

---
 appkit/window/class.rs          | 69 ++++++++++++++++++++++++++++++++-
 appkit/window/controller/mod.rs | 16 --------
 appkit/window/traits.rs         |  8 ++++
 3 files changed, 76 insertions(+), 17 deletions(-)

diff --git a/appkit/window/class.rs b/appkit/window/class.rs
index 2782895..4a3f360 100644
--- a/appkit/window/class.rs
+++ b/appkit/window/class.rs
@@ -12,7 +12,7 @@ use crate::foundation::id;
 use crate::utils::load;
 use crate::window::{WindowDelegate, WINDOW_DELEGATE_PTR};
 
-/// Called when an `NSWindow` receives a `windowWillClose:` event.
+/// Called when an `NSWindowDelegate` receives a `windowWillClose:` event.
 /// Good place to clean up memory and what not.
 extern fn will_close<T: WindowDelegate>(this: &Object, _: Sel, _: id) {
     let window = load::<T>(this, WINDOW_DELEGATE_PTR);
@@ -25,6 +25,66 @@ extern fn will_close<T: WindowDelegate>(this: &Object, _: Sel, _: id) {
     Rc::into_raw(window);
 }
 
+/// Called when an `NSWindowDelegate` receives a `windowWillMove:` event.
+extern fn will_move<T: WindowDelegate>(this: &Object, _: Sel, _: id) {
+    let window = load::<T>(this, WINDOW_DELEGATE_PTR);
+
+    {
+        let window = window.borrow();
+        (*window).will_move();
+    }
+
+    Rc::into_raw(window);
+}
+
+/// Called when an `NSWindowDelegate` receives a `windowDidMove:` event.
+extern fn did_move<T: WindowDelegate>(this: &Object, _: Sel, _: id) {
+    let window = load::<T>(this, WINDOW_DELEGATE_PTR);
+
+    {
+        let window = window.borrow();
+        (*window).did_move();
+    }
+
+    Rc::into_raw(window);
+}
+
+/// Called when an `NSWindowDelegate` receives a `windowDidChangeScreen:` event.
+extern fn did_change_screen<T: WindowDelegate>(this: &Object, _: Sel, _: id) {
+    let window = load::<T>(this, WINDOW_DELEGATE_PTR);
+
+    {
+        let window = window.borrow();
+        (*window).did_change_screen();
+    }
+
+    Rc::into_raw(window);
+}
+
+/// Called when an `NSWindowDelegate` receives a `windowDidChangeScreenProfile:` event.
+extern fn did_change_screen_profile<T: WindowDelegate>(this: &Object, _: Sel, _: id) {
+    let window = load::<T>(this, WINDOW_DELEGATE_PTR);
+
+    {
+        let window = window.borrow();
+        (*window).did_change_screen_profile();
+    }
+
+    Rc::into_raw(window);
+}
+
+/// Called when an `NSWindowDelegate` receives a `windowDidChangeBackingProperties:` event.
+extern fn did_change_backing_properties<T: WindowDelegate>(this: &Object, _: Sel, _: id) {
+    let window = load::<T>(this, WINDOW_DELEGATE_PTR);
+
+    {
+        let window = window.borrow();
+        (*window).did_change_backing_properties();
+    }
+
+    Rc::into_raw(window);
+}
+
 /// Injects an `NSWindow` subclass, with some callback and pointer ivars for what we
 /// need to do.
 pub(crate) fn register_window_class() -> *const Class {
@@ -58,6 +118,13 @@ pub(crate) fn register_window_class_with_delegate<T: WindowDelegate>() -> *const
 
         // NSWindowDelegate methods
         decl.add_method(sel!(windowWillClose:), will_close::<T> as extern fn(&Object, _, _));
+
+        // Moving Windows
+        decl.add_method(sel!(windowWillMove:), will_move::<T> as extern fn(&Object, _, _));
+        decl.add_method(sel!(windowDidMove:), did_move::<T> as extern fn(&Object, _, _));
+        decl.add_method(sel!(windowDidChangeScreen:), did_change_screen::<T> as extern fn(&Object, _, _));
+        decl.add_method(sel!(windowDidChangeScreenProfile:), did_change_screen_profile::<T> as extern fn(&Object, _, _));
+        decl.add_method(sel!(windowDidChangeBackingProperties:), did_change_backing_properties::<T> as extern fn(&Object, _, _));
         
         DELEGATE_CLASS = decl.register();
     });
diff --git a/appkit/window/controller/mod.rs b/appkit/window/controller/mod.rs
index ca4552b..f8ce31a 100644
--- a/appkit/window/controller/mod.rs
+++ b/appkit/window/controller/mod.rs
@@ -74,19 +74,3 @@ impl<T> WindowController<T> where T: WindowDelegate + 'static {
         }
     }
 }
-
-/*impl<T> Drop for Window<T> {
-    /// When a Window is dropped on the Rust side, we want to ensure that we break the delegate
-    /// link on the Objective-C side. While this shouldn't actually be an issue, I'd rather be
-    /// safer than sorry.
-    ///
-    /// We also clean up our loopback pointer that we use for callbacks.
-    fn drop(&mut self) {
-        unsafe { 
-                let window: id = msg_send![*objc_controller, window];
-                let _: () = msg_send![window, setDelegate:nil];
-
-            let _ = Rc::from_raw(self.internal_callback_ptr);
-        }
-    }
-}*/
diff --git a/appkit/window/traits.rs b/appkit/window/traits.rs
index e0a5e1c..af82826 100644
--- a/appkit/window/traits.rs
+++ b/appkit/window/traits.rs
@@ -28,6 +28,14 @@ pub trait WindowDelegate {
     /// such as rendering in retina vs non-retina environments.
     fn did_change_screen(&self) {}
 
+    /// Fired when the window profile changes screens - you might find this useful for certain scenarios,
+    /// such as rendering in retina vs non-retina environments.
+    fn did_change_screen_profile(&self) {}
+
+    /// Fired when the window backing properties change - you might find this useful for certain scenarios,
+    /// such as rendering in retina vs non-retina environments. It's rare to need this though.
+    fn did_change_backing_properties(&self) {}
+
     /// Fires when this window is about to become the key window.
     fn did_become_key(&self) {}