window.rs

   1use super::{ns_string, renderer, MacDisplay, NSRange, NSStringExt};
   2use crate::{
   3    platform::PlatformInputHandler, point, px, size, AnyWindowHandle, Bounds, DisplayLink,
   4    ExternalPaths, FileDropEvent, ForegroundExecutor, KeyDownEvent, Keystroke, Modifiers,
   5    ModifiersChangedEvent, MouseButton, MouseDownEvent, MouseMoveEvent, MouseUpEvent, Pixels,
   6    PlatformAtlas, PlatformDisplay, PlatformInput, PlatformWindow, Point, PromptLevel,
   7    RequestFrameOptions, ScaledPixels, Size, Timer, WindowAppearance, WindowBackgroundAppearance,
   8    WindowBounds, WindowKind, WindowParams,
   9};
  10use block::ConcreteBlock;
  11use cocoa::{
  12    appkit::{
  13        NSApplication, NSBackingStoreBuffered, NSColor, NSEvent, NSEventModifierFlags,
  14        NSFilenamesPboardType, NSPasteboard, NSScreen, NSView, NSViewHeightSizable,
  15        NSViewWidthSizable, NSWindow, NSWindowButton, NSWindowCollectionBehavior,
  16        NSWindowOcclusionState, NSWindowStyleMask, NSWindowTitleVisibility,
  17    },
  18    base::{id, nil},
  19    foundation::{
  20        NSArray, NSAutoreleasePool, NSDictionary, NSFastEnumeration, NSInteger, NSPoint, NSRect,
  21        NSSize, NSString, NSUInteger,
  22    },
  23};
  24use core_graphics::display::{CGDirectDisplayID, CGPoint, CGRect};
  25use ctor::ctor;
  26use futures::channel::oneshot;
  27use objc::{
  28    class,
  29    declare::ClassDecl,
  30    msg_send,
  31    runtime::{Class, Object, Protocol, Sel, BOOL, NO, YES},
  32    sel, sel_impl,
  33};
  34use parking_lot::Mutex;
  35use raw_window_handle as rwh;
  36use smallvec::SmallVec;
  37use std::{
  38    cell::Cell,
  39    ffi::{c_void, CStr},
  40    mem,
  41    ops::Range,
  42    path::PathBuf,
  43    ptr::{self, NonNull},
  44    rc::Rc,
  45    sync::{Arc, Weak},
  46    time::Duration,
  47};
  48use util::ResultExt;
  49
  50const WINDOW_STATE_IVAR: &str = "windowState";
  51
  52static mut WINDOW_CLASS: *const Class = ptr::null();
  53static mut PANEL_CLASS: *const Class = ptr::null();
  54static mut VIEW_CLASS: *const Class = ptr::null();
  55
  56#[allow(non_upper_case_globals)]
  57const NSWindowStyleMaskNonactivatingPanel: NSWindowStyleMask =
  58    NSWindowStyleMask::from_bits_retain(1 << 7);
  59#[allow(non_upper_case_globals)]
  60const NSNormalWindowLevel: NSInteger = 0;
  61#[allow(non_upper_case_globals)]
  62const NSPopUpWindowLevel: NSInteger = 101;
  63#[allow(non_upper_case_globals)]
  64const NSTrackingMouseEnteredAndExited: NSUInteger = 0x01;
  65#[allow(non_upper_case_globals)]
  66const NSTrackingMouseMoved: NSUInteger = 0x02;
  67#[allow(non_upper_case_globals)]
  68const NSTrackingActiveAlways: NSUInteger = 0x80;
  69#[allow(non_upper_case_globals)]
  70const NSTrackingInVisibleRect: NSUInteger = 0x200;
  71#[allow(non_upper_case_globals)]
  72const NSWindowAnimationBehaviorUtilityWindow: NSInteger = 4;
  73#[allow(non_upper_case_globals)]
  74const NSViewLayerContentsRedrawDuringViewResize: NSInteger = 2;
  75// https://developer.apple.com/documentation/appkit/nsdragoperation
  76type NSDragOperation = NSUInteger;
  77#[allow(non_upper_case_globals)]
  78const NSDragOperationNone: NSDragOperation = 0;
  79#[allow(non_upper_case_globals)]
  80const NSDragOperationCopy: NSDragOperation = 1;
  81
  82#[link(name = "CoreGraphics", kind = "framework")]
  83extern "C" {
  84    // Widely used private APIs; Apple uses them for their Terminal.app.
  85    fn CGSMainConnectionID() -> id;
  86    fn CGSSetWindowBackgroundBlurRadius(
  87        connection_id: id,
  88        window_id: NSInteger,
  89        radius: i64,
  90    ) -> i32;
  91}
  92
  93#[ctor]
  94unsafe fn build_classes() {
  95    WINDOW_CLASS = build_window_class("GPUIWindow", class!(NSWindow));
  96    PANEL_CLASS = build_window_class("GPUIPanel", class!(NSPanel));
  97    VIEW_CLASS = {
  98        let mut decl = ClassDecl::new("GPUIView", class!(NSView)).unwrap();
  99        decl.add_ivar::<*mut c_void>(WINDOW_STATE_IVAR);
 100
 101        decl.add_method(sel!(dealloc), dealloc_view as extern "C" fn(&Object, Sel));
 102
 103        decl.add_method(
 104            sel!(performKeyEquivalent:),
 105            handle_key_equivalent as extern "C" fn(&Object, Sel, id) -> BOOL,
 106        );
 107        decl.add_method(
 108            sel!(keyDown:),
 109            handle_key_down as extern "C" fn(&Object, Sel, id),
 110        );
 111        decl.add_method(
 112            sel!(mouseDown:),
 113            handle_view_event as extern "C" fn(&Object, Sel, id),
 114        );
 115        decl.add_method(
 116            sel!(mouseUp:),
 117            handle_view_event as extern "C" fn(&Object, Sel, id),
 118        );
 119        decl.add_method(
 120            sel!(rightMouseDown:),
 121            handle_view_event as extern "C" fn(&Object, Sel, id),
 122        );
 123        decl.add_method(
 124            sel!(rightMouseUp:),
 125            handle_view_event as extern "C" fn(&Object, Sel, id),
 126        );
 127        decl.add_method(
 128            sel!(otherMouseDown:),
 129            handle_view_event as extern "C" fn(&Object, Sel, id),
 130        );
 131        decl.add_method(
 132            sel!(otherMouseUp:),
 133            handle_view_event as extern "C" fn(&Object, Sel, id),
 134        );
 135        decl.add_method(
 136            sel!(mouseMoved:),
 137            handle_view_event as extern "C" fn(&Object, Sel, id),
 138        );
 139        decl.add_method(
 140            sel!(mouseExited:),
 141            handle_view_event as extern "C" fn(&Object, Sel, id),
 142        );
 143        decl.add_method(
 144            sel!(mouseDragged:),
 145            handle_view_event as extern "C" fn(&Object, Sel, id),
 146        );
 147        decl.add_method(
 148            sel!(scrollWheel:),
 149            handle_view_event as extern "C" fn(&Object, Sel, id),
 150        );
 151        decl.add_method(
 152            sel!(swipeWithEvent:),
 153            handle_view_event as extern "C" fn(&Object, Sel, id),
 154        );
 155        decl.add_method(
 156            sel!(flagsChanged:),
 157            handle_view_event as extern "C" fn(&Object, Sel, id),
 158        );
 159
 160        decl.add_method(
 161            sel!(makeBackingLayer),
 162            make_backing_layer as extern "C" fn(&Object, Sel) -> id,
 163        );
 164
 165        decl.add_protocol(Protocol::get("CALayerDelegate").unwrap());
 166        decl.add_method(
 167            sel!(viewDidChangeBackingProperties),
 168            view_did_change_backing_properties as extern "C" fn(&Object, Sel),
 169        );
 170        decl.add_method(
 171            sel!(setFrameSize:),
 172            set_frame_size as extern "C" fn(&Object, Sel, NSSize),
 173        );
 174        decl.add_method(
 175            sel!(displayLayer:),
 176            display_layer as extern "C" fn(&Object, Sel, id),
 177        );
 178
 179        decl.add_protocol(Protocol::get("NSTextInputClient").unwrap());
 180        decl.add_method(
 181            sel!(validAttributesForMarkedText),
 182            valid_attributes_for_marked_text as extern "C" fn(&Object, Sel) -> id,
 183        );
 184        decl.add_method(
 185            sel!(hasMarkedText),
 186            has_marked_text as extern "C" fn(&Object, Sel) -> BOOL,
 187        );
 188        decl.add_method(
 189            sel!(markedRange),
 190            marked_range as extern "C" fn(&Object, Sel) -> NSRange,
 191        );
 192        decl.add_method(
 193            sel!(selectedRange),
 194            selected_range as extern "C" fn(&Object, Sel) -> NSRange,
 195        );
 196        decl.add_method(
 197            sel!(firstRectForCharacterRange:actualRange:),
 198            first_rect_for_character_range as extern "C" fn(&Object, Sel, NSRange, id) -> NSRect,
 199        );
 200        decl.add_method(
 201            sel!(insertText:replacementRange:),
 202            insert_text as extern "C" fn(&Object, Sel, id, NSRange),
 203        );
 204        decl.add_method(
 205            sel!(setMarkedText:selectedRange:replacementRange:),
 206            set_marked_text as extern "C" fn(&Object, Sel, id, NSRange, NSRange),
 207        );
 208        decl.add_method(sel!(unmarkText), unmark_text as extern "C" fn(&Object, Sel));
 209        decl.add_method(
 210            sel!(attributedSubstringForProposedRange:actualRange:),
 211            attributed_substring_for_proposed_range
 212                as extern "C" fn(&Object, Sel, NSRange, *mut c_void) -> id,
 213        );
 214        decl.add_method(
 215            sel!(viewDidChangeEffectiveAppearance),
 216            view_did_change_effective_appearance as extern "C" fn(&Object, Sel),
 217        );
 218
 219        // Suppress beep on keystrokes with modifier keys.
 220        decl.add_method(
 221            sel!(doCommandBySelector:),
 222            do_command_by_selector as extern "C" fn(&Object, Sel, Sel),
 223        );
 224
 225        decl.add_method(
 226            sel!(acceptsFirstMouse:),
 227            accepts_first_mouse as extern "C" fn(&Object, Sel, id) -> BOOL,
 228        );
 229
 230        decl.register()
 231    };
 232}
 233
 234pub(crate) fn convert_mouse_position(position: NSPoint, window_height: Pixels) -> Point<Pixels> {
 235    point(
 236        px(position.x as f32),
 237        // macOS screen coordinates are relative to bottom left
 238        window_height - px(position.y as f32),
 239    )
 240}
 241
 242unsafe fn build_window_class(name: &'static str, superclass: &Class) -> *const Class {
 243    let mut decl = ClassDecl::new(name, superclass).unwrap();
 244    decl.add_ivar::<*mut c_void>(WINDOW_STATE_IVAR);
 245    decl.add_method(sel!(dealloc), dealloc_window as extern "C" fn(&Object, Sel));
 246    decl.add_method(
 247        sel!(canBecomeMainWindow),
 248        yes as extern "C" fn(&Object, Sel) -> BOOL,
 249    );
 250    decl.add_method(
 251        sel!(canBecomeKeyWindow),
 252        yes as extern "C" fn(&Object, Sel) -> BOOL,
 253    );
 254    decl.add_method(
 255        sel!(windowDidResize:),
 256        window_did_resize as extern "C" fn(&Object, Sel, id),
 257    );
 258    decl.add_method(
 259        sel!(windowDidChangeOcclusionState:),
 260        window_did_change_occlusion_state as extern "C" fn(&Object, Sel, id),
 261    );
 262    decl.add_method(
 263        sel!(windowWillEnterFullScreen:),
 264        window_will_enter_fullscreen as extern "C" fn(&Object, Sel, id),
 265    );
 266    decl.add_method(
 267        sel!(windowDidMove:),
 268        window_did_move as extern "C" fn(&Object, Sel, id),
 269    );
 270    decl.add_method(
 271        sel!(windowDidChangeScreen:),
 272        window_did_change_screen as extern "C" fn(&Object, Sel, id),
 273    );
 274    decl.add_method(
 275        sel!(windowDidBecomeKey:),
 276        window_did_change_key_status as extern "C" fn(&Object, Sel, id),
 277    );
 278    decl.add_method(
 279        sel!(windowDidResignKey:),
 280        window_did_change_key_status as extern "C" fn(&Object, Sel, id),
 281    );
 282    decl.add_method(
 283        sel!(windowShouldClose:),
 284        window_should_close as extern "C" fn(&Object, Sel, id) -> BOOL,
 285    );
 286
 287    decl.add_method(sel!(close), close_window as extern "C" fn(&Object, Sel));
 288
 289    decl.add_method(
 290        sel!(draggingEntered:),
 291        dragging_entered as extern "C" fn(&Object, Sel, id) -> NSDragOperation,
 292    );
 293    decl.add_method(
 294        sel!(draggingUpdated:),
 295        dragging_updated as extern "C" fn(&Object, Sel, id) -> NSDragOperation,
 296    );
 297    decl.add_method(
 298        sel!(draggingExited:),
 299        dragging_exited as extern "C" fn(&Object, Sel, id),
 300    );
 301    decl.add_method(
 302        sel!(performDragOperation:),
 303        perform_drag_operation as extern "C" fn(&Object, Sel, id) -> BOOL,
 304    );
 305    decl.add_method(
 306        sel!(concludeDragOperation:),
 307        conclude_drag_operation as extern "C" fn(&Object, Sel, id),
 308    );
 309
 310    decl.register()
 311}
 312
 313struct MacWindowState {
 314    handle: AnyWindowHandle,
 315    executor: ForegroundExecutor,
 316    native_window: id,
 317    native_view: NonNull<Object>,
 318    display_link: Option<DisplayLink>,
 319    renderer: renderer::Renderer,
 320    request_frame_callback: Option<Box<dyn FnMut(RequestFrameOptions)>>,
 321    event_callback: Option<Box<dyn FnMut(PlatformInput) -> crate::DispatchEventResult>>,
 322    activate_callback: Option<Box<dyn FnMut(bool)>>,
 323    resize_callback: Option<Box<dyn FnMut(Size<Pixels>, f32)>>,
 324    moved_callback: Option<Box<dyn FnMut()>>,
 325    should_close_callback: Option<Box<dyn FnMut() -> bool>>,
 326    close_callback: Option<Box<dyn FnOnce()>>,
 327    appearance_changed_callback: Option<Box<dyn FnMut()>>,
 328    input_handler: Option<PlatformInputHandler>,
 329    last_key_equivalent: Option<KeyDownEvent>,
 330    synthetic_drag_counter: usize,
 331    traffic_light_position: Option<Point<Pixels>>,
 332    previous_modifiers_changed_event: Option<PlatformInput>,
 333    keystroke_for_do_command: Option<Keystroke>,
 334    do_command_handled: Option<bool>,
 335    external_files_dragged: bool,
 336    // Whether the next left-mouse click is also the focusing click.
 337    first_mouse: bool,
 338    fullscreen_restore_bounds: Bounds<Pixels>,
 339}
 340
 341impl MacWindowState {
 342    fn move_traffic_light(&self) {
 343        if let Some(traffic_light_position) = self.traffic_light_position {
 344            if self.is_fullscreen() {
 345                // Moving traffic lights while fullscreen doesn't work,
 346                // see https://github.com/zed-industries/zed/issues/4712
 347                return;
 348            }
 349
 350            let titlebar_height = self.titlebar_height();
 351
 352            unsafe {
 353                let close_button: id = msg_send![
 354                    self.native_window,
 355                    standardWindowButton: NSWindowButton::NSWindowCloseButton
 356                ];
 357                let min_button: id = msg_send![
 358                    self.native_window,
 359                    standardWindowButton: NSWindowButton::NSWindowMiniaturizeButton
 360                ];
 361                let zoom_button: id = msg_send![
 362                    self.native_window,
 363                    standardWindowButton: NSWindowButton::NSWindowZoomButton
 364                ];
 365
 366                let mut close_button_frame: CGRect = msg_send![close_button, frame];
 367                let mut min_button_frame: CGRect = msg_send![min_button, frame];
 368                let mut zoom_button_frame: CGRect = msg_send![zoom_button, frame];
 369                let mut origin = point(
 370                    traffic_light_position.x,
 371                    titlebar_height
 372                        - traffic_light_position.y
 373                        - px(close_button_frame.size.height as f32),
 374                );
 375                let button_spacing =
 376                    px((min_button_frame.origin.x - close_button_frame.origin.x) as f32);
 377
 378                close_button_frame.origin = CGPoint::new(origin.x.into(), origin.y.into());
 379                let _: () = msg_send![close_button, setFrame: close_button_frame];
 380                origin.x += button_spacing;
 381
 382                min_button_frame.origin = CGPoint::new(origin.x.into(), origin.y.into());
 383                let _: () = msg_send![min_button, setFrame: min_button_frame];
 384                origin.x += button_spacing;
 385
 386                zoom_button_frame.origin = CGPoint::new(origin.x.into(), origin.y.into());
 387                let _: () = msg_send![zoom_button, setFrame: zoom_button_frame];
 388                origin.x += button_spacing;
 389            }
 390        }
 391    }
 392
 393    fn start_display_link(&mut self) {
 394        self.stop_display_link();
 395        unsafe {
 396            if !self
 397                .native_window
 398                .occlusionState()
 399                .contains(NSWindowOcclusionState::NSWindowOcclusionStateVisible)
 400            {
 401                return;
 402            }
 403        }
 404        let display_id = unsafe { display_id_for_screen(self.native_window.screen()) };
 405        if let Some(mut display_link) =
 406            DisplayLink::new(display_id, self.native_view.as_ptr() as *mut c_void, step).log_err()
 407        {
 408            display_link.start().log_err();
 409            self.display_link = Some(display_link);
 410        }
 411    }
 412
 413    fn stop_display_link(&mut self) {
 414        self.display_link = None;
 415    }
 416
 417    fn is_maximized(&self) -> bool {
 418        unsafe {
 419            let bounds = self.bounds();
 420            let screen_size = self.native_window.screen().visibleFrame().into();
 421            bounds.size == screen_size
 422        }
 423    }
 424
 425    fn is_fullscreen(&self) -> bool {
 426        unsafe {
 427            let style_mask = self.native_window.styleMask();
 428            style_mask.contains(NSWindowStyleMask::NSFullScreenWindowMask)
 429        }
 430    }
 431
 432    fn bounds(&self) -> Bounds<Pixels> {
 433        let mut window_frame = unsafe { NSWindow::frame(self.native_window) };
 434        let screen_frame = unsafe {
 435            let screen = NSWindow::screen(self.native_window);
 436            NSScreen::frame(screen)
 437        };
 438
 439        // Flip the y coordinate to be top-left origin
 440        window_frame.origin.y =
 441            screen_frame.size.height - window_frame.origin.y - window_frame.size.height;
 442
 443        Bounds::new(
 444            point(
 445                px((window_frame.origin.x - screen_frame.origin.x) as f32),
 446                px((window_frame.origin.y + screen_frame.origin.y) as f32),
 447            ),
 448            size(
 449                px(window_frame.size.width as f32),
 450                px(window_frame.size.height as f32),
 451            ),
 452        )
 453    }
 454
 455    fn content_size(&self) -> Size<Pixels> {
 456        let NSSize { width, height, .. } =
 457            unsafe { NSView::frame(self.native_window.contentView()) }.size;
 458        size(px(width as f32), px(height as f32))
 459    }
 460
 461    fn scale_factor(&self) -> f32 {
 462        get_scale_factor(self.native_window)
 463    }
 464
 465    fn titlebar_height(&self) -> Pixels {
 466        unsafe {
 467            let frame = NSWindow::frame(self.native_window);
 468            let content_layout_rect: CGRect = msg_send![self.native_window, contentLayoutRect];
 469            px((frame.size.height - content_layout_rect.size.height) as f32)
 470        }
 471    }
 472
 473    fn window_bounds(&self) -> WindowBounds {
 474        if self.is_fullscreen() {
 475            WindowBounds::Fullscreen(self.fullscreen_restore_bounds)
 476        } else {
 477            WindowBounds::Windowed(self.bounds())
 478        }
 479    }
 480}
 481
 482unsafe impl Send for MacWindowState {}
 483
 484pub(crate) struct MacWindow(Arc<Mutex<MacWindowState>>);
 485
 486impl MacWindow {
 487    pub fn open(
 488        handle: AnyWindowHandle,
 489        WindowParams {
 490            bounds,
 491            titlebar,
 492            kind,
 493            is_movable,
 494            focus,
 495            show,
 496            display_id,
 497            window_min_size,
 498        }: WindowParams,
 499        executor: ForegroundExecutor,
 500        renderer_context: renderer::Context,
 501    ) -> Self {
 502        unsafe {
 503            let pool = NSAutoreleasePool::new(nil);
 504
 505            let mut style_mask;
 506            if let Some(titlebar) = titlebar.as_ref() {
 507                style_mask = NSWindowStyleMask::NSClosableWindowMask
 508                    | NSWindowStyleMask::NSMiniaturizableWindowMask
 509                    | NSWindowStyleMask::NSResizableWindowMask
 510                    | NSWindowStyleMask::NSTitledWindowMask;
 511
 512                if titlebar.appears_transparent {
 513                    style_mask |= NSWindowStyleMask::NSFullSizeContentViewWindowMask;
 514                }
 515            } else {
 516                style_mask = NSWindowStyleMask::NSTitledWindowMask
 517                    | NSWindowStyleMask::NSFullSizeContentViewWindowMask;
 518            }
 519
 520            let native_window: id = match kind {
 521                WindowKind::Normal => msg_send![WINDOW_CLASS, alloc],
 522                WindowKind::PopUp => {
 523                    style_mask |= NSWindowStyleMaskNonactivatingPanel;
 524                    msg_send![PANEL_CLASS, alloc]
 525                }
 526            };
 527
 528            let display = display_id
 529                .and_then(MacDisplay::find_by_id)
 530                .unwrap_or_else(MacDisplay::primary);
 531
 532            let mut target_screen = nil;
 533            let mut screen_frame = None;
 534
 535            let screens = NSScreen::screens(nil);
 536            let count: u64 = cocoa::foundation::NSArray::count(screens);
 537            for i in 0..count {
 538                let screen = cocoa::foundation::NSArray::objectAtIndex(screens, i);
 539                let frame = NSScreen::frame(screen);
 540                let display_id = display_id_for_screen(screen);
 541                if display_id == display.0 {
 542                    screen_frame = Some(frame);
 543                    target_screen = screen;
 544                }
 545            }
 546
 547            let screen_frame = screen_frame.unwrap_or_else(|| {
 548                let screen = NSScreen::mainScreen(nil);
 549                target_screen = screen;
 550                NSScreen::frame(screen)
 551            });
 552
 553            let window_rect = NSRect::new(
 554                NSPoint::new(
 555                    screen_frame.origin.x + bounds.origin.x.0 as f64,
 556                    screen_frame.origin.y
 557                        + (display.bounds().size.height - bounds.origin.y).0 as f64,
 558                ),
 559                NSSize::new(bounds.size.width.0 as f64, bounds.size.height.0 as f64),
 560            );
 561
 562            let native_window = native_window.initWithContentRect_styleMask_backing_defer_screen_(
 563                window_rect,
 564                style_mask,
 565                NSBackingStoreBuffered,
 566                NO,
 567                target_screen,
 568            );
 569            assert!(!native_window.is_null());
 570            let () = msg_send![
 571                native_window,
 572                registerForDraggedTypes:
 573                    NSArray::arrayWithObject(nil, NSFilenamesPboardType)
 574            ];
 575            let () = msg_send![
 576                native_window,
 577                setReleasedWhenClosed: NO
 578            ];
 579
 580            let native_view: id = msg_send![VIEW_CLASS, alloc];
 581            let native_view = NSView::init(native_view);
 582            assert!(!native_view.is_null());
 583
 584            let mut window = Self(Arc::new(Mutex::new(MacWindowState {
 585                handle,
 586                executor,
 587                native_window,
 588                native_view: NonNull::new_unchecked(native_view),
 589                display_link: None,
 590                renderer: renderer::new_renderer(
 591                    renderer_context,
 592                    native_window as *mut _,
 593                    native_view as *mut _,
 594                    bounds.size.map(|pixels| pixels.0),
 595                    false,
 596                ),
 597                request_frame_callback: None,
 598                event_callback: None,
 599                activate_callback: None,
 600                resize_callback: None,
 601                moved_callback: None,
 602                should_close_callback: None,
 603                close_callback: None,
 604                appearance_changed_callback: None,
 605                input_handler: None,
 606                last_key_equivalent: None,
 607                synthetic_drag_counter: 0,
 608                traffic_light_position: titlebar
 609                    .as_ref()
 610                    .and_then(|titlebar| titlebar.traffic_light_position),
 611                previous_modifiers_changed_event: None,
 612                keystroke_for_do_command: None,
 613                do_command_handled: None,
 614                external_files_dragged: false,
 615                first_mouse: false,
 616                fullscreen_restore_bounds: Bounds::default(),
 617            })));
 618
 619            (*native_window).set_ivar(
 620                WINDOW_STATE_IVAR,
 621                Arc::into_raw(window.0.clone()) as *const c_void,
 622            );
 623            native_window.setDelegate_(native_window);
 624            (*native_view).set_ivar(
 625                WINDOW_STATE_IVAR,
 626                Arc::into_raw(window.0.clone()) as *const c_void,
 627            );
 628
 629            if let Some(title) = titlebar
 630                .as_ref()
 631                .and_then(|t| t.title.as_ref().map(AsRef::as_ref))
 632            {
 633                window.set_title(title);
 634            }
 635
 636            native_window.setMovable_(is_movable as BOOL);
 637
 638            if let Some(window_min_size) = window_min_size {
 639                native_window.setContentMinSize_(NSSize {
 640                    width: window_min_size.width.to_f64(),
 641                    height: window_min_size.height.to_f64(),
 642                });
 643            }
 644
 645            if titlebar.map_or(true, |titlebar| titlebar.appears_transparent) {
 646                native_window.setTitlebarAppearsTransparent_(YES);
 647                native_window.setTitleVisibility_(NSWindowTitleVisibility::NSWindowTitleHidden);
 648            }
 649
 650            native_view.setAutoresizingMask_(NSViewWidthSizable | NSViewHeightSizable);
 651            native_view.setWantsBestResolutionOpenGLSurface_(YES);
 652
 653            // From winit crate: On Mojave, views automatically become layer-backed shortly after
 654            // being added to a native_window. Changing the layer-backedness of a view breaks the
 655            // association between the view and its associated OpenGL context. To work around this,
 656            // on we explicitly make the view layer-backed up front so that AppKit doesn't do it
 657            // itself and break the association with its context.
 658            native_view.setWantsLayer(YES);
 659            let _: () = msg_send![
 660                native_view,
 661                setLayerContentsRedrawPolicy: NSViewLayerContentsRedrawDuringViewResize
 662            ];
 663
 664            native_window.setContentView_(native_view.autorelease());
 665            native_window.makeFirstResponder_(native_view);
 666
 667            match kind {
 668                WindowKind::Normal => {
 669                    native_window.setLevel_(NSNormalWindowLevel);
 670                    native_window.setAcceptsMouseMovedEvents_(YES);
 671                }
 672                WindowKind::PopUp => {
 673                    // Use a tracking area to allow receiving MouseMoved events even when
 674                    // the window or application aren't active, which is often the case
 675                    // e.g. for notification windows.
 676                    let tracking_area: id = msg_send![class!(NSTrackingArea), alloc];
 677                    let _: () = msg_send![
 678                        tracking_area,
 679                        initWithRect: NSRect::new(NSPoint::new(0., 0.), NSSize::new(0., 0.))
 680                        options: NSTrackingMouseEnteredAndExited | NSTrackingMouseMoved | NSTrackingActiveAlways | NSTrackingInVisibleRect
 681                        owner: native_view
 682                        userInfo: nil
 683                    ];
 684                    let _: () =
 685                        msg_send![native_view, addTrackingArea: tracking_area.autorelease()];
 686
 687                    native_window.setLevel_(NSPopUpWindowLevel);
 688                    let _: () = msg_send![
 689                        native_window,
 690                        setAnimationBehavior: NSWindowAnimationBehaviorUtilityWindow
 691                    ];
 692                    native_window.setCollectionBehavior_(
 693                        NSWindowCollectionBehavior::NSWindowCollectionBehaviorCanJoinAllSpaces |
 694                        NSWindowCollectionBehavior::NSWindowCollectionBehaviorFullScreenAuxiliary
 695                    );
 696                }
 697            }
 698
 699            if focus && show {
 700                native_window.makeKeyAndOrderFront_(nil);
 701            } else if show {
 702                native_window.orderFront_(nil);
 703            }
 704
 705            // Set the initial position of the window to the specified origin.
 706            // Although we already specified the position using `initWithContentRect_styleMask_backing_defer_screen_`,
 707            // the window position might be incorrect if the main screen (the screen that contains the window that has focus)
 708            //  is different from the primary screen.
 709            NSWindow::setFrameTopLeftPoint_(native_window, window_rect.origin);
 710            window.0.lock().move_traffic_light();
 711
 712            pool.drain();
 713
 714            window
 715        }
 716    }
 717
 718    pub fn active_window() -> Option<AnyWindowHandle> {
 719        unsafe {
 720            let app = NSApplication::sharedApplication(nil);
 721            let main_window: id = msg_send![app, mainWindow];
 722            if msg_send![main_window, isKindOfClass: WINDOW_CLASS] {
 723                let handle = get_window_state(&*main_window).lock().handle;
 724                Some(handle)
 725            } else {
 726                None
 727            }
 728        }
 729    }
 730
 731    pub fn ordered_windows() -> Vec<AnyWindowHandle> {
 732        unsafe {
 733            let app = NSApplication::sharedApplication(nil);
 734            let windows: id = msg_send![app, orderedWindows];
 735            let count: NSUInteger = msg_send![windows, count];
 736
 737            let mut window_handles = Vec::new();
 738            for i in 0..count {
 739                let window: id = msg_send![windows, objectAtIndex:i];
 740                if msg_send![window, isKindOfClass: WINDOW_CLASS] {
 741                    let handle = get_window_state(&*window).lock().handle;
 742                    window_handles.push(handle);
 743                }
 744            }
 745
 746            window_handles
 747        }
 748    }
 749}
 750
 751impl Drop for MacWindow {
 752    fn drop(&mut self) {
 753        let mut this = self.0.lock();
 754        this.renderer.destroy();
 755        let window = this.native_window;
 756        this.display_link.take();
 757        unsafe {
 758            this.native_window.setDelegate_(nil);
 759        }
 760        this.input_handler.take();
 761        this.executor
 762            .spawn(async move {
 763                unsafe {
 764                    window.close();
 765                    window.autorelease();
 766                }
 767            })
 768            .detach();
 769    }
 770}
 771
 772impl PlatformWindow for MacWindow {
 773    fn bounds(&self) -> Bounds<Pixels> {
 774        self.0.as_ref().lock().bounds()
 775    }
 776
 777    fn window_bounds(&self) -> WindowBounds {
 778        self.0.as_ref().lock().window_bounds()
 779    }
 780
 781    fn is_maximized(&self) -> bool {
 782        self.0.as_ref().lock().is_maximized()
 783    }
 784
 785    fn content_size(&self) -> Size<Pixels> {
 786        self.0.as_ref().lock().content_size()
 787    }
 788
 789    fn scale_factor(&self) -> f32 {
 790        self.0.as_ref().lock().scale_factor()
 791    }
 792
 793    fn appearance(&self) -> WindowAppearance {
 794        unsafe {
 795            let appearance: id = msg_send![self.0.lock().native_window, effectiveAppearance];
 796            WindowAppearance::from_native(appearance)
 797        }
 798    }
 799
 800    fn display(&self) -> Option<Rc<dyn PlatformDisplay>> {
 801        unsafe {
 802            let screen = self.0.lock().native_window.screen();
 803            let device_description: id = msg_send![screen, deviceDescription];
 804            let screen_number: id = NSDictionary::valueForKey_(
 805                device_description,
 806                NSString::alloc(nil).init_str("NSScreenNumber"),
 807            );
 808
 809            let screen_number: u32 = msg_send![screen_number, unsignedIntValue];
 810
 811            Some(Rc::new(MacDisplay(screen_number)))
 812        }
 813    }
 814
 815    fn mouse_position(&self) -> Point<Pixels> {
 816        let position = unsafe {
 817            self.0
 818                .lock()
 819                .native_window
 820                .mouseLocationOutsideOfEventStream()
 821        };
 822        convert_mouse_position(position, self.content_size().height)
 823    }
 824
 825    fn modifiers(&self) -> Modifiers {
 826        unsafe {
 827            let modifiers: NSEventModifierFlags = msg_send![class!(NSEvent), modifierFlags];
 828
 829            let control = modifiers.contains(NSEventModifierFlags::NSControlKeyMask);
 830            let alt = modifiers.contains(NSEventModifierFlags::NSAlternateKeyMask);
 831            let shift = modifiers.contains(NSEventModifierFlags::NSShiftKeyMask);
 832            let command = modifiers.contains(NSEventModifierFlags::NSCommandKeyMask);
 833            let function = modifiers.contains(NSEventModifierFlags::NSFunctionKeyMask);
 834
 835            Modifiers {
 836                control,
 837                alt,
 838                shift,
 839                platform: command,
 840                function,
 841            }
 842        }
 843    }
 844
 845    fn set_input_handler(&mut self, input_handler: PlatformInputHandler) {
 846        self.0.as_ref().lock().input_handler = Some(input_handler);
 847    }
 848
 849    fn take_input_handler(&mut self) -> Option<PlatformInputHandler> {
 850        self.0.as_ref().lock().input_handler.take()
 851    }
 852
 853    fn prompt(
 854        &self,
 855        level: PromptLevel,
 856        msg: &str,
 857        detail: Option<&str>,
 858        answers: &[&str],
 859    ) -> Option<oneshot::Receiver<usize>> {
 860        // macOs applies overrides to modal window buttons after they are added.
 861        // Two most important for this logic are:
 862        // * Buttons with "Cancel" title will be displayed as the last buttons in the modal
 863        // * Last button added to the modal via `addButtonWithTitle` stays focused
 864        // * Focused buttons react on "space"/" " keypresses
 865        // * Usage of `keyEquivalent`, `makeFirstResponder` or `setInitialFirstResponder` does not change the focus
 866        //
 867        // See also https://developer.apple.com/documentation/appkit/nsalert/1524532-addbuttonwithtitle#discussion
 868        // ```
 869        // By default, the first button has a key equivalent of Return,
 870        // any button with a title of “Cancel” has a key equivalent of Escape,
 871        // and any button with the title “Don’t Save” has a key equivalent of Command-D (but only if it’s not the first button).
 872        // ```
 873        //
 874        // To avoid situations when the last element added is "Cancel" and it gets the focus
 875        // (hence stealing both ESC and Space shortcuts), we find and add one non-Cancel button
 876        // last, so it gets focus and a Space shortcut.
 877        // This way, "Save this file? Yes/No/Cancel"-ish modals will get all three buttons mapped with a key.
 878        let latest_non_cancel_label = answers
 879            .iter()
 880            .enumerate()
 881            .rev()
 882            .find(|(_, &label)| label != "Cancel")
 883            .filter(|&(label_index, _)| label_index > 0);
 884
 885        unsafe {
 886            let alert: id = msg_send![class!(NSAlert), alloc];
 887            let alert: id = msg_send![alert, init];
 888            let alert_style = match level {
 889                PromptLevel::Info => 1,
 890                PromptLevel::Warning => 0,
 891                PromptLevel::Critical => 2,
 892            };
 893            let _: () = msg_send![alert, setAlertStyle: alert_style];
 894            let _: () = msg_send![alert, setMessageText: ns_string(msg)];
 895            if let Some(detail) = detail {
 896                let _: () = msg_send![alert, setInformativeText: ns_string(detail)];
 897            }
 898
 899            for (ix, answer) in answers
 900                .iter()
 901                .enumerate()
 902                .filter(|&(ix, _)| Some(ix) != latest_non_cancel_label.map(|(ix, _)| ix))
 903            {
 904                let button: id = msg_send![alert, addButtonWithTitle: ns_string(answer)];
 905                let _: () = msg_send![button, setTag: ix as NSInteger];
 906            }
 907            if let Some((ix, answer)) = latest_non_cancel_label {
 908                let button: id = msg_send![alert, addButtonWithTitle: ns_string(answer)];
 909                let _: () = msg_send![button, setTag: ix as NSInteger];
 910            }
 911
 912            let (done_tx, done_rx) = oneshot::channel();
 913            let done_tx = Cell::new(Some(done_tx));
 914            let block = ConcreteBlock::new(move |answer: NSInteger| {
 915                if let Some(done_tx) = done_tx.take() {
 916                    let _ = done_tx.send(answer.try_into().unwrap());
 917                }
 918            });
 919            let block = block.copy();
 920            let native_window = self.0.lock().native_window;
 921            let executor = self.0.lock().executor.clone();
 922            executor
 923                .spawn(async move {
 924                    let _: () = msg_send![
 925                        alert,
 926                        beginSheetModalForWindow: native_window
 927                        completionHandler: block
 928                    ];
 929                })
 930                .detach();
 931
 932            Some(done_rx)
 933        }
 934    }
 935
 936    fn activate(&self) {
 937        let window = self.0.lock().native_window;
 938        let executor = self.0.lock().executor.clone();
 939        executor
 940            .spawn(async move {
 941                unsafe {
 942                    let _: () = msg_send![window, makeKeyAndOrderFront: nil];
 943                }
 944            })
 945            .detach();
 946    }
 947
 948    fn is_active(&self) -> bool {
 949        unsafe { self.0.lock().native_window.isKeyWindow() == YES }
 950    }
 951
 952    // is_hovered is unused on macOS. See Window::is_window_hovered.
 953    fn is_hovered(&self) -> bool {
 954        false
 955    }
 956
 957    fn set_title(&mut self, title: &str) {
 958        unsafe {
 959            let app = NSApplication::sharedApplication(nil);
 960            let window = self.0.lock().native_window;
 961            let title = ns_string(title);
 962            let _: () = msg_send![app, changeWindowsItem:window title:title filename:false];
 963            let _: () = msg_send![window, setTitle: title];
 964            self.0.lock().move_traffic_light();
 965        }
 966    }
 967
 968    fn set_app_id(&mut self, _app_id: &str) {}
 969
 970    fn set_background_appearance(&self, background_appearance: WindowBackgroundAppearance) {
 971        let mut this = self.0.as_ref().lock();
 972        this.renderer
 973            .update_transparency(background_appearance != WindowBackgroundAppearance::Opaque);
 974
 975        let blur_radius = if background_appearance == WindowBackgroundAppearance::Blurred {
 976            80
 977        } else {
 978            0
 979        };
 980        let opaque = if background_appearance == WindowBackgroundAppearance::Opaque {
 981            YES
 982        } else {
 983            NO
 984        };
 985        unsafe {
 986            this.native_window.setOpaque_(opaque);
 987            // Shadows for transparent windows cause artifacts and performance issues
 988            this.native_window.setHasShadow_(opaque);
 989            let clear_color = if opaque == YES {
 990                NSColor::colorWithSRGBRed_green_blue_alpha_(nil, 0f64, 0f64, 0f64, 1f64)
 991            } else {
 992                NSColor::clearColor(nil)
 993            };
 994            this.native_window.setBackgroundColor_(clear_color);
 995            let window_number = this.native_window.windowNumber();
 996            CGSSetWindowBackgroundBlurRadius(CGSMainConnectionID(), window_number, blur_radius);
 997        }
 998    }
 999
1000    fn set_edited(&mut self, edited: bool) {
1001        unsafe {
1002            let window = self.0.lock().native_window;
1003            msg_send![window, setDocumentEdited: edited as BOOL]
1004        }
1005
1006        // Changing the document edited state resets the traffic light position,
1007        // so we have to move it again.
1008        self.0.lock().move_traffic_light();
1009    }
1010
1011    fn show_character_palette(&self) {
1012        let this = self.0.lock();
1013        let window = this.native_window;
1014        this.executor
1015            .spawn(async move {
1016                unsafe {
1017                    let app = NSApplication::sharedApplication(nil);
1018                    let _: () = msg_send![app, orderFrontCharacterPalette: window];
1019                }
1020            })
1021            .detach();
1022    }
1023
1024    fn minimize(&self) {
1025        let window = self.0.lock().native_window;
1026        unsafe {
1027            window.miniaturize_(nil);
1028        }
1029    }
1030
1031    fn zoom(&self) {
1032        let this = self.0.lock();
1033        let window = this.native_window;
1034        this.executor
1035            .spawn(async move {
1036                unsafe {
1037                    window.zoom_(nil);
1038                }
1039            })
1040            .detach();
1041    }
1042
1043    fn toggle_fullscreen(&self) {
1044        let this = self.0.lock();
1045        let window = this.native_window;
1046        this.executor
1047            .spawn(async move {
1048                unsafe {
1049                    window.toggleFullScreen_(nil);
1050                }
1051            })
1052            .detach();
1053    }
1054
1055    fn is_fullscreen(&self) -> bool {
1056        let this = self.0.lock();
1057        let window = this.native_window;
1058
1059        unsafe {
1060            window
1061                .styleMask()
1062                .contains(NSWindowStyleMask::NSFullScreenWindowMask)
1063        }
1064    }
1065
1066    fn on_request_frame(&self, callback: Box<dyn FnMut(RequestFrameOptions)>) {
1067        self.0.as_ref().lock().request_frame_callback = Some(callback);
1068    }
1069
1070    fn on_input(&self, callback: Box<dyn FnMut(PlatformInput) -> crate::DispatchEventResult>) {
1071        self.0.as_ref().lock().event_callback = Some(callback);
1072    }
1073
1074    fn on_active_status_change(&self, callback: Box<dyn FnMut(bool)>) {
1075        self.0.as_ref().lock().activate_callback = Some(callback);
1076    }
1077
1078    fn on_hover_status_change(&self, _: Box<dyn FnMut(bool)>) {}
1079
1080    fn on_resize(&self, callback: Box<dyn FnMut(Size<Pixels>, f32)>) {
1081        self.0.as_ref().lock().resize_callback = Some(callback);
1082    }
1083
1084    fn on_moved(&self, callback: Box<dyn FnMut()>) {
1085        self.0.as_ref().lock().moved_callback = Some(callback);
1086    }
1087
1088    fn on_should_close(&self, callback: Box<dyn FnMut() -> bool>) {
1089        self.0.as_ref().lock().should_close_callback = Some(callback);
1090    }
1091
1092    fn on_close(&self, callback: Box<dyn FnOnce()>) {
1093        self.0.as_ref().lock().close_callback = Some(callback);
1094    }
1095
1096    fn on_appearance_changed(&self, callback: Box<dyn FnMut()>) {
1097        self.0.lock().appearance_changed_callback = Some(callback);
1098    }
1099
1100    fn draw(&self, scene: &crate::Scene) {
1101        let mut this = self.0.lock();
1102        this.renderer.draw(scene);
1103    }
1104
1105    fn sprite_atlas(&self) -> Arc<dyn PlatformAtlas> {
1106        self.0.lock().renderer.sprite_atlas().clone()
1107    }
1108
1109    fn gpu_specs(&self) -> Option<crate::GpuSpecs> {
1110        None
1111    }
1112
1113    fn update_ime_position(&self, _bounds: Bounds<ScaledPixels>) {
1114        let executor = self.0.lock().executor.clone();
1115        executor
1116            .spawn(async move {
1117                unsafe {
1118                    let input_context: id =
1119                        msg_send![class!(NSTextInputContext), currentInputContext];
1120                    let _: () = msg_send![input_context, invalidateCharacterCoordinates];
1121                }
1122            })
1123            .detach()
1124    }
1125}
1126
1127impl rwh::HasWindowHandle for MacWindow {
1128    fn window_handle(&self) -> Result<rwh::WindowHandle<'_>, rwh::HandleError> {
1129        // SAFETY: The AppKitWindowHandle is a wrapper around a pointer to an NSView
1130        unsafe {
1131            Ok(rwh::WindowHandle::borrow_raw(rwh::RawWindowHandle::AppKit(
1132                rwh::AppKitWindowHandle::new(self.0.lock().native_view.cast()),
1133            )))
1134        }
1135    }
1136}
1137
1138impl rwh::HasDisplayHandle for MacWindow {
1139    fn display_handle(&self) -> Result<rwh::DisplayHandle<'_>, rwh::HandleError> {
1140        // SAFETY: This is a no-op on macOS
1141        unsafe {
1142            Ok(rwh::DisplayHandle::borrow_raw(
1143                rwh::AppKitDisplayHandle::new().into(),
1144            ))
1145        }
1146    }
1147}
1148
1149fn get_scale_factor(native_window: id) -> f32 {
1150    let factor = unsafe {
1151        let screen: id = msg_send![native_window, screen];
1152        NSScreen::backingScaleFactor(screen) as f32
1153    };
1154
1155    // We are not certain what triggers this, but it seems that sometimes
1156    // this method would return 0 (https://github.com/zed-industries/zed/issues/6412)
1157    // It seems most likely that this would happen if the window has no screen
1158    // (if it is off-screen), though we'd expect to see viewDidChangeBackingProperties before
1159    // it was rendered for real.
1160    // Regardless, attempt to avoid the issue here.
1161    if factor == 0.0 {
1162        2.
1163    } else {
1164        factor
1165    }
1166}
1167
1168unsafe fn get_window_state(object: &Object) -> Arc<Mutex<MacWindowState>> {
1169    let raw: *mut c_void = *object.get_ivar(WINDOW_STATE_IVAR);
1170    let rc1 = Arc::from_raw(raw as *mut Mutex<MacWindowState>);
1171    let rc2 = rc1.clone();
1172    mem::forget(rc1);
1173    rc2
1174}
1175
1176unsafe fn drop_window_state(object: &Object) {
1177    let raw: *mut c_void = *object.get_ivar(WINDOW_STATE_IVAR);
1178    Arc::from_raw(raw as *mut Mutex<MacWindowState>);
1179}
1180
1181extern "C" fn yes(_: &Object, _: Sel) -> BOOL {
1182    YES
1183}
1184
1185extern "C" fn dealloc_window(this: &Object, _: Sel) {
1186    unsafe {
1187        drop_window_state(this);
1188        let _: () = msg_send![super(this, class!(NSWindow)), dealloc];
1189    }
1190}
1191
1192extern "C" fn dealloc_view(this: &Object, _: Sel) {
1193    unsafe {
1194        drop_window_state(this);
1195        let _: () = msg_send![super(this, class!(NSView)), dealloc];
1196    }
1197}
1198
1199extern "C" fn handle_key_equivalent(this: &Object, _: Sel, native_event: id) -> BOOL {
1200    handle_key_event(this, native_event, true)
1201}
1202
1203extern "C" fn handle_key_down(this: &Object, _: Sel, native_event: id) {
1204    handle_key_event(this, native_event, false);
1205}
1206
1207// Things to test if you're modifying this method:
1208//  U.S. layout:
1209//   - The IME consumes characters like 'j' and 'k', which makes paging through `less` in
1210//     the terminal behave incorrectly by default. This behavior should be patched by our
1211//     IME integration
1212//   - `alt-t` should open the tasks menu
1213//   - In vim mode, this keybinding should work:
1214//     ```
1215//        {
1216//          "context": "Editor && vim_mode == insert",
1217//          "bindings": {"j j": "vim::NormalBefore"}
1218//        }
1219//     ```
1220//     and typing 'j k' in insert mode with this keybinding should insert the two characters
1221//  Brazilian layout:
1222//   - `" space` should create an unmarked quote
1223//   - `" backspace` should delete the marked quote
1224//   - `" "`should create an unmarked quote and a second marked quote
1225//   - `" up` should insert a quote, unmark it, and move up one line
1226//   - `" cmd-down` should insert a quote, unmark it, and move to the end of the file
1227//   - `cmd-ctrl-space` and clicking on an emoji should type it
1228//  Czech (QWERTY) layout:
1229//   - in vim mode `option-4`  should go to end of line (same as $)
1230//  Japanese (Romaji) layout:
1231//   - type `a i left down up enter enter` should create an unmarked text "愛"
1232extern "C" fn handle_key_event(this: &Object, native_event: id, key_equivalent: bool) -> BOOL {
1233    let window_state = unsafe { get_window_state(this) };
1234    let mut lock = window_state.as_ref().lock();
1235
1236    let window_height = lock.content_size().height;
1237    let event = unsafe { PlatformInput::from_native(native_event, Some(window_height)) };
1238
1239    let Some(PlatformInput::KeyDown(mut event)) = event else {
1240        return NO;
1241    };
1242    // For certain keystrokes, macOS will first dispatch a "key equivalent" event.
1243    // If that event isn't handled, it will then dispatch a "key down" event. GPUI
1244    // makes no distinction between these two types of events, so we need to ignore
1245    // the "key down" event if we've already just processed its "key equivalent" version.
1246    if key_equivalent {
1247        lock.last_key_equivalent = Some(event.clone());
1248    } else if lock.last_key_equivalent.take().as_ref() == Some(&event) {
1249        return NO;
1250    }
1251
1252    drop(lock);
1253
1254    let is_composing = with_input_handler(this, |input_handler| input_handler.marked_text_range())
1255        .flatten()
1256        .is_some();
1257
1258    // If we're composing, send the key to the input handler first;
1259    // otherwise we only send to the input handler if we don't have a matching binding.
1260    // The input handler may call `do_command_by_selector` if it doesn't know how to handle
1261    // a key. If it does so, it will return YES so we won't send the key twice.
1262    // We also do this for non-printing keys (like arrow keys and escape) as the IME menu
1263    // may need them even if there is no marked text;
1264    // however we skip keys with control or the input handler adds control-characters to the buffer.
1265    // and keys with function, as the input handler swallows them.
1266    if is_composing
1267        || (event.keystroke.key_char.is_none()
1268            && !event.keystroke.modifiers.control
1269            && !event.keystroke.modifiers.function)
1270    {
1271        {
1272            let mut lock = window_state.as_ref().lock();
1273            lock.keystroke_for_do_command = Some(event.keystroke.clone());
1274            lock.do_command_handled.take();
1275            drop(lock);
1276        }
1277
1278        let handled: BOOL = unsafe {
1279            let input_context: id = msg_send![this, inputContext];
1280            msg_send![input_context, handleEvent: native_event]
1281        };
1282        window_state.as_ref().lock().keystroke_for_do_command.take();
1283        if let Some(handled) = window_state.as_ref().lock().do_command_handled.take() {
1284            return handled as BOOL;
1285        } else if handled == YES {
1286            return YES;
1287        }
1288
1289        let mut callback = window_state.as_ref().lock().event_callback.take();
1290        let handled: BOOL = if let Some(callback) = callback.as_mut() {
1291            !callback(PlatformInput::KeyDown(event)).propagate as BOOL
1292        } else {
1293            NO
1294        };
1295        window_state.as_ref().lock().event_callback = callback;
1296        return handled as BOOL;
1297    }
1298
1299    let mut callback = window_state.as_ref().lock().event_callback.take();
1300    let handled = if let Some(callback) = callback.as_mut() {
1301        !callback(PlatformInput::KeyDown(event.clone())).propagate as BOOL
1302    } else {
1303        NO
1304    };
1305    window_state.as_ref().lock().event_callback = callback;
1306    if handled == YES {
1307        return YES;
1308    }
1309
1310    if event.is_held {
1311        if let Some(key_char) = event.keystroke.key_char.as_ref() {
1312            let handled = with_input_handler(&this, |input_handler| {
1313                if !input_handler.apple_press_and_hold_enabled() {
1314                    input_handler.replace_text_in_range(None, &key_char);
1315                    return YES;
1316                }
1317                NO
1318            });
1319            if handled == Some(YES) {
1320                return YES;
1321            }
1322        }
1323    }
1324
1325    // Don't send key equivalents to the input handler,
1326    // or macOS shortcuts like cmd-` will stop working.
1327    if key_equivalent {
1328        return NO;
1329    }
1330
1331    unsafe {
1332        let input_context: id = msg_send![this, inputContext];
1333        msg_send![input_context, handleEvent: native_event]
1334    }
1335}
1336
1337extern "C" fn handle_view_event(this: &Object, _: Sel, native_event: id) {
1338    let window_state = unsafe { get_window_state(this) };
1339    let weak_window_state = Arc::downgrade(&window_state);
1340    let mut lock = window_state.as_ref().lock();
1341    let window_height = lock.content_size().height;
1342    let event = unsafe { PlatformInput::from_native(native_event, Some(window_height)) };
1343
1344    if let Some(mut event) = event {
1345        match &mut event {
1346            PlatformInput::MouseDown(
1347                event @ MouseDownEvent {
1348                    button: MouseButton::Left,
1349                    modifiers: Modifiers { control: true, .. },
1350                    ..
1351                },
1352            ) => {
1353                // On mac, a ctrl-left click should be handled as a right click.
1354                *event = MouseDownEvent {
1355                    button: MouseButton::Right,
1356                    modifiers: Modifiers {
1357                        control: false,
1358                        ..event.modifiers
1359                    },
1360                    click_count: 1,
1361                    ..*event
1362                };
1363            }
1364
1365            // Handles focusing click.
1366            PlatformInput::MouseDown(
1367                event @ MouseDownEvent {
1368                    button: MouseButton::Left,
1369                    ..
1370                },
1371            ) if (lock.first_mouse) => {
1372                *event = MouseDownEvent {
1373                    first_mouse: true,
1374                    ..*event
1375                };
1376                lock.first_mouse = false;
1377            }
1378
1379            // Because we map a ctrl-left_down to a right_down -> right_up let's ignore
1380            // the ctrl-left_up to avoid having a mismatch in button down/up events if the
1381            // user is still holding ctrl when releasing the left mouse button
1382            PlatformInput::MouseUp(
1383                event @ MouseUpEvent {
1384                    button: MouseButton::Left,
1385                    modifiers: Modifiers { control: true, .. },
1386                    ..
1387                },
1388            ) => {
1389                *event = MouseUpEvent {
1390                    button: MouseButton::Right,
1391                    modifiers: Modifiers {
1392                        control: false,
1393                        ..event.modifiers
1394                    },
1395                    click_count: 1,
1396                    ..*event
1397                };
1398            }
1399
1400            _ => {}
1401        };
1402
1403        match &event {
1404            PlatformInput::MouseDown(_) => {
1405                drop(lock);
1406                unsafe {
1407                    let input_context: id = msg_send![this, inputContext];
1408                    msg_send![input_context, handleEvent: native_event]
1409                }
1410                lock = window_state.as_ref().lock();
1411            }
1412            PlatformInput::MouseMove(
1413                event @ MouseMoveEvent {
1414                    pressed_button: Some(_),
1415                    ..
1416                },
1417            ) => {
1418                // Synthetic drag is used for selecting long buffer contents while buffer is being scrolled.
1419                // External file drag and drop is able to emit its own synthetic mouse events which will conflict
1420                // with these ones.
1421                if !lock.external_files_dragged {
1422                    lock.synthetic_drag_counter += 1;
1423                    let executor = lock.executor.clone();
1424                    executor
1425                        .spawn(synthetic_drag(
1426                            weak_window_state,
1427                            lock.synthetic_drag_counter,
1428                            event.clone(),
1429                        ))
1430                        .detach();
1431                }
1432            }
1433
1434            PlatformInput::MouseUp(MouseUpEvent { .. }) => {
1435                lock.synthetic_drag_counter += 1;
1436            }
1437
1438            PlatformInput::ModifiersChanged(ModifiersChangedEvent { modifiers }) => {
1439                // Only raise modifiers changed event when they have actually changed
1440                if let Some(PlatformInput::ModifiersChanged(ModifiersChangedEvent {
1441                    modifiers: prev_modifiers,
1442                })) = &lock.previous_modifiers_changed_event
1443                {
1444                    if prev_modifiers == modifiers {
1445                        return;
1446                    }
1447                }
1448
1449                lock.previous_modifiers_changed_event = Some(event.clone());
1450            }
1451
1452            _ => {}
1453        }
1454
1455        if let Some(mut callback) = lock.event_callback.take() {
1456            drop(lock);
1457            callback(event);
1458            window_state.lock().event_callback = Some(callback);
1459        }
1460    }
1461}
1462
1463extern "C" fn window_did_change_occlusion_state(this: &Object, _: Sel, _: id) {
1464    let window_state = unsafe { get_window_state(this) };
1465    let lock = &mut *window_state.lock();
1466    unsafe {
1467        if lock
1468            .native_window
1469            .occlusionState()
1470            .contains(NSWindowOcclusionState::NSWindowOcclusionStateVisible)
1471        {
1472            lock.start_display_link();
1473        } else {
1474            lock.stop_display_link();
1475        }
1476    }
1477}
1478
1479extern "C" fn window_did_resize(this: &Object, _: Sel, _: id) {
1480    let window_state = unsafe { get_window_state(this) };
1481    window_state.as_ref().lock().move_traffic_light();
1482}
1483
1484extern "C" fn window_will_enter_fullscreen(this: &Object, _: Sel, _: id) {
1485    let window_state = unsafe { get_window_state(this) };
1486    let mut lock = window_state.as_ref().lock();
1487    lock.fullscreen_restore_bounds = lock.bounds();
1488}
1489
1490extern "C" fn window_did_move(this: &Object, _: Sel, _: id) {
1491    let window_state = unsafe { get_window_state(this) };
1492    let mut lock = window_state.as_ref().lock();
1493    if let Some(mut callback) = lock.moved_callback.take() {
1494        drop(lock);
1495        callback();
1496        window_state.lock().moved_callback = Some(callback);
1497    }
1498}
1499
1500extern "C" fn window_did_change_screen(this: &Object, _: Sel, _: id) {
1501    let window_state = unsafe { get_window_state(this) };
1502    let mut lock = window_state.as_ref().lock();
1503    lock.start_display_link();
1504}
1505
1506extern "C" fn window_did_change_key_status(this: &Object, selector: Sel, _: id) {
1507    let window_state = unsafe { get_window_state(this) };
1508    let lock = window_state.lock();
1509    let is_active = unsafe { lock.native_window.isKeyWindow() == YES };
1510
1511    // When opening a pop-up while the application isn't active, Cocoa sends a spurious
1512    // `windowDidBecomeKey` message to the previous key window even though that window
1513    // isn't actually key. This causes a bug if the application is later activated while
1514    // the pop-up is still open, making it impossible to activate the previous key window
1515    // even if the pop-up gets closed. The only way to activate it again is to de-activate
1516    // the app and re-activate it, which is a pretty bad UX.
1517    // The following code detects the spurious event and invokes `resignKeyWindow`:
1518    // in theory, we're not supposed to invoke this method manually but it balances out
1519    // the spurious `becomeKeyWindow` event and helps us work around that bug.
1520    if selector == sel!(windowDidBecomeKey:) && !is_active {
1521        unsafe {
1522            let _: () = msg_send![lock.native_window, resignKeyWindow];
1523            return;
1524        }
1525    }
1526
1527    let executor = lock.executor.clone();
1528    drop(lock);
1529    executor
1530        .spawn(async move {
1531            let mut lock = window_state.as_ref().lock();
1532            if let Some(mut callback) = lock.activate_callback.take() {
1533                drop(lock);
1534                callback(is_active);
1535                window_state.lock().activate_callback = Some(callback);
1536            };
1537        })
1538        .detach();
1539}
1540
1541extern "C" fn window_should_close(this: &Object, _: Sel, _: id) -> BOOL {
1542    let window_state = unsafe { get_window_state(this) };
1543    let mut lock = window_state.as_ref().lock();
1544    if let Some(mut callback) = lock.should_close_callback.take() {
1545        drop(lock);
1546        let should_close = callback();
1547        window_state.lock().should_close_callback = Some(callback);
1548        should_close as BOOL
1549    } else {
1550        YES
1551    }
1552}
1553
1554extern "C" fn close_window(this: &Object, _: Sel) {
1555    unsafe {
1556        let close_callback = {
1557            let window_state = get_window_state(this);
1558            let mut lock = window_state.as_ref().lock();
1559            lock.close_callback.take()
1560        };
1561
1562        if let Some(callback) = close_callback {
1563            callback();
1564        }
1565
1566        let _: () = msg_send![super(this, class!(NSWindow)), close];
1567    }
1568}
1569
1570extern "C" fn make_backing_layer(this: &Object, _: Sel) -> id {
1571    let window_state = unsafe { get_window_state(this) };
1572    let window_state = window_state.as_ref().lock();
1573    window_state.renderer.layer_ptr() as id
1574}
1575
1576extern "C" fn view_did_change_backing_properties(this: &Object, _: Sel) {
1577    let window_state = unsafe { get_window_state(this) };
1578    let mut lock = window_state.as_ref().lock();
1579
1580    let scale_factor = lock.scale_factor();
1581    let size = lock.content_size();
1582    let drawable_size = size.to_device_pixels(scale_factor);
1583    unsafe {
1584        let _: () = msg_send![
1585            lock.renderer.layer(),
1586            setContentsScale: scale_factor as f64
1587        ];
1588    }
1589
1590    lock.renderer.update_drawable_size(drawable_size);
1591
1592    if let Some(mut callback) = lock.resize_callback.take() {
1593        let content_size = lock.content_size();
1594        let scale_factor = lock.scale_factor();
1595        drop(lock);
1596        callback(content_size, scale_factor);
1597        window_state.as_ref().lock().resize_callback = Some(callback);
1598    };
1599}
1600
1601extern "C" fn set_frame_size(this: &Object, _: Sel, size: NSSize) {
1602    let window_state = unsafe { get_window_state(this) };
1603    let mut lock = window_state.as_ref().lock();
1604
1605    let new_size = Size::<Pixels>::from(size);
1606    if lock.content_size() == new_size {
1607        return;
1608    }
1609
1610    unsafe {
1611        let _: () = msg_send![super(this, class!(NSView)), setFrameSize: size];
1612    }
1613
1614    let scale_factor = lock.scale_factor();
1615    let drawable_size = new_size.to_device_pixels(scale_factor);
1616    lock.renderer.update_drawable_size(drawable_size);
1617
1618    if let Some(mut callback) = lock.resize_callback.take() {
1619        let content_size = lock.content_size();
1620        let scale_factor = lock.scale_factor();
1621        drop(lock);
1622        callback(content_size, scale_factor);
1623        window_state.lock().resize_callback = Some(callback);
1624    };
1625}
1626
1627extern "C" fn display_layer(this: &Object, _: Sel, _: id) {
1628    let window_state = unsafe { get_window_state(this) };
1629    let mut lock = window_state.lock();
1630    if let Some(mut callback) = lock.request_frame_callback.take() {
1631        #[cfg(not(feature = "macos-blade"))]
1632        lock.renderer.set_presents_with_transaction(true);
1633        lock.stop_display_link();
1634        drop(lock);
1635        callback(Default::default());
1636
1637        let mut lock = window_state.lock();
1638        lock.request_frame_callback = Some(callback);
1639        #[cfg(not(feature = "macos-blade"))]
1640        lock.renderer.set_presents_with_transaction(false);
1641        lock.start_display_link();
1642    }
1643}
1644
1645unsafe extern "C" fn step(view: *mut c_void) {
1646    let view = view as id;
1647    let window_state = unsafe { get_window_state(&*view) };
1648    let mut lock = window_state.lock();
1649
1650    if let Some(mut callback) = lock.request_frame_callback.take() {
1651        drop(lock);
1652        callback(Default::default());
1653        window_state.lock().request_frame_callback = Some(callback);
1654    }
1655}
1656
1657extern "C" fn valid_attributes_for_marked_text(_: &Object, _: Sel) -> id {
1658    unsafe { msg_send![class!(NSArray), array] }
1659}
1660
1661extern "C" fn has_marked_text(this: &Object, _: Sel) -> BOOL {
1662    let has_marked_text_result =
1663        with_input_handler(this, |input_handler| input_handler.marked_text_range()).flatten();
1664
1665    has_marked_text_result.is_some() as BOOL
1666}
1667
1668extern "C" fn marked_range(this: &Object, _: Sel) -> NSRange {
1669    let marked_range_result =
1670        with_input_handler(this, |input_handler| input_handler.marked_text_range()).flatten();
1671
1672    marked_range_result.map_or(NSRange::invalid(), |range| range.into())
1673}
1674
1675extern "C" fn selected_range(this: &Object, _: Sel) -> NSRange {
1676    let selected_range_result = with_input_handler(this, |input_handler| {
1677        input_handler.selected_text_range(false)
1678    })
1679    .flatten();
1680
1681    selected_range_result.map_or(NSRange::invalid(), |selection| selection.range.into())
1682}
1683
1684extern "C" fn first_rect_for_character_range(
1685    this: &Object,
1686    _: Sel,
1687    range: NSRange,
1688    _: id,
1689) -> NSRect {
1690    let frame: NSRect = unsafe {
1691        let state = get_window_state(this);
1692        let lock = state.lock();
1693        let mut frame = NSWindow::frame(lock.native_window);
1694        let content_layout_rect: CGRect = msg_send![lock.native_window, contentLayoutRect];
1695        let style_mask: NSWindowStyleMask = msg_send![lock.native_window, styleMask];
1696        if !style_mask.contains(NSWindowStyleMask::NSFullSizeContentViewWindowMask) {
1697            frame.origin.y -= frame.size.height - content_layout_rect.size.height;
1698        }
1699        frame
1700    };
1701    with_input_handler(this, |input_handler| {
1702        input_handler.bounds_for_range(range.to_range()?)
1703    })
1704    .flatten()
1705    .map_or(
1706        NSRect::new(NSPoint::new(0., 0.), NSSize::new(0., 0.)),
1707        |bounds| {
1708            NSRect::new(
1709                NSPoint::new(
1710                    frame.origin.x + bounds.origin.x.0 as f64,
1711                    frame.origin.y + frame.size.height
1712                        - bounds.origin.y.0 as f64
1713                        - bounds.size.height.0 as f64,
1714                ),
1715                NSSize::new(bounds.size.width.0 as f64, bounds.size.height.0 as f64),
1716            )
1717        },
1718    )
1719}
1720
1721extern "C" fn insert_text(this: &Object, _: Sel, text: id, replacement_range: NSRange) {
1722    unsafe {
1723        let is_attributed_string: BOOL =
1724            msg_send![text, isKindOfClass: [class!(NSAttributedString)]];
1725        let text: id = if is_attributed_string == YES {
1726            msg_send![text, string]
1727        } else {
1728            text
1729        };
1730
1731        let text = text.to_str();
1732        let replacement_range = replacement_range.to_range();
1733        with_input_handler(this, |input_handler| {
1734            input_handler.replace_text_in_range(replacement_range, &text)
1735        });
1736    }
1737}
1738
1739extern "C" fn set_marked_text(
1740    this: &Object,
1741    _: Sel,
1742    text: id,
1743    selected_range: NSRange,
1744    replacement_range: NSRange,
1745) {
1746    unsafe {
1747        let is_attributed_string: BOOL =
1748            msg_send![text, isKindOfClass: [class!(NSAttributedString)]];
1749        let text: id = if is_attributed_string == YES {
1750            msg_send![text, string]
1751        } else {
1752            text
1753        };
1754        let selected_range = selected_range.to_range();
1755        let replacement_range = replacement_range.to_range();
1756        let text = text.to_str();
1757        with_input_handler(this, |input_handler| {
1758            input_handler.replace_and_mark_text_in_range(replacement_range, &text, selected_range)
1759        });
1760    }
1761}
1762extern "C" fn unmark_text(this: &Object, _: Sel) {
1763    with_input_handler(this, |input_handler| input_handler.unmark_text());
1764}
1765
1766extern "C" fn attributed_substring_for_proposed_range(
1767    this: &Object,
1768    _: Sel,
1769    range: NSRange,
1770    actual_range: *mut c_void,
1771) -> id {
1772    with_input_handler(this, |input_handler| {
1773        let range = range.to_range()?;
1774        if range.is_empty() {
1775            return None;
1776        }
1777        let mut adjusted: Option<Range<usize>> = None;
1778
1779        let selected_text = input_handler.text_for_range(range.clone(), &mut adjusted)?;
1780        if let Some(adjusted) = adjusted {
1781            if adjusted != range {
1782                unsafe { (actual_range as *mut NSRange).write(NSRange::from(adjusted)) };
1783            }
1784        }
1785        unsafe {
1786            let string: id = msg_send![class!(NSAttributedString), alloc];
1787            let string: id = msg_send![string, initWithString: ns_string(&selected_text)];
1788            Some(string)
1789        }
1790    })
1791    .flatten()
1792    .unwrap_or(nil)
1793}
1794
1795// We ignore which selector it asks us to do because the user may have
1796// bound the shortcut to something else.
1797extern "C" fn do_command_by_selector(this: &Object, _: Sel, _: Sel) {
1798    let state = unsafe { get_window_state(this) };
1799    let mut lock = state.as_ref().lock();
1800    let keystroke = lock.keystroke_for_do_command.take();
1801    let mut event_callback = lock.event_callback.take();
1802    drop(lock);
1803
1804    if let Some((keystroke, mut callback)) = keystroke.zip(event_callback.as_mut()) {
1805        let handled = (callback)(PlatformInput::KeyDown(KeyDownEvent {
1806            keystroke,
1807            is_held: false,
1808        }));
1809        state.as_ref().lock().do_command_handled = Some(!handled.propagate);
1810    }
1811
1812    state.as_ref().lock().event_callback = event_callback;
1813}
1814
1815extern "C" fn view_did_change_effective_appearance(this: &Object, _: Sel) {
1816    unsafe {
1817        let state = get_window_state(this);
1818        let mut lock = state.as_ref().lock();
1819        if let Some(mut callback) = lock.appearance_changed_callback.take() {
1820            drop(lock);
1821            callback();
1822            state.lock().appearance_changed_callback = Some(callback);
1823        }
1824    }
1825}
1826
1827extern "C" fn accepts_first_mouse(this: &Object, _: Sel, _: id) -> BOOL {
1828    let window_state = unsafe { get_window_state(this) };
1829    let mut lock = window_state.as_ref().lock();
1830    lock.first_mouse = true;
1831    YES
1832}
1833
1834extern "C" fn dragging_entered(this: &Object, _: Sel, dragging_info: id) -> NSDragOperation {
1835    let window_state = unsafe { get_window_state(this) };
1836    let position = drag_event_position(&window_state, dragging_info);
1837    let paths = external_paths_from_event(dragging_info);
1838    if let Some(event) =
1839        paths.map(|paths| PlatformInput::FileDrop(FileDropEvent::Entered { position, paths }))
1840    {
1841        if send_new_event(&window_state, event) {
1842            window_state.lock().external_files_dragged = true;
1843            return NSDragOperationCopy;
1844        }
1845    }
1846    NSDragOperationNone
1847}
1848
1849extern "C" fn dragging_updated(this: &Object, _: Sel, dragging_info: id) -> NSDragOperation {
1850    let window_state = unsafe { get_window_state(this) };
1851    let position = drag_event_position(&window_state, dragging_info);
1852    if send_new_event(
1853        &window_state,
1854        PlatformInput::FileDrop(FileDropEvent::Pending { position }),
1855    ) {
1856        NSDragOperationCopy
1857    } else {
1858        NSDragOperationNone
1859    }
1860}
1861
1862extern "C" fn dragging_exited(this: &Object, _: Sel, _: id) {
1863    let window_state = unsafe { get_window_state(this) };
1864    send_new_event(
1865        &window_state,
1866        PlatformInput::FileDrop(FileDropEvent::Exited),
1867    );
1868    window_state.lock().external_files_dragged = false;
1869}
1870
1871extern "C" fn perform_drag_operation(this: &Object, _: Sel, dragging_info: id) -> BOOL {
1872    let window_state = unsafe { get_window_state(this) };
1873    let position = drag_event_position(&window_state, dragging_info);
1874    if send_new_event(
1875        &window_state,
1876        PlatformInput::FileDrop(FileDropEvent::Submit { position }),
1877    ) {
1878        YES
1879    } else {
1880        NO
1881    }
1882}
1883
1884fn external_paths_from_event(dragging_info: *mut Object) -> Option<ExternalPaths> {
1885    let mut paths = SmallVec::new();
1886    let pasteboard: id = unsafe { msg_send![dragging_info, draggingPasteboard] };
1887    let filenames = unsafe { NSPasteboard::propertyListForType(pasteboard, NSFilenamesPboardType) };
1888    if filenames == nil {
1889        return None;
1890    }
1891    for file in unsafe { filenames.iter() } {
1892        let path = unsafe {
1893            let f = NSString::UTF8String(file);
1894            CStr::from_ptr(f).to_string_lossy().into_owned()
1895        };
1896        paths.push(PathBuf::from(path))
1897    }
1898    Some(ExternalPaths(paths))
1899}
1900
1901extern "C" fn conclude_drag_operation(this: &Object, _: Sel, _: id) {
1902    let window_state = unsafe { get_window_state(this) };
1903    send_new_event(
1904        &window_state,
1905        PlatformInput::FileDrop(FileDropEvent::Exited),
1906    );
1907}
1908
1909async fn synthetic_drag(
1910    window_state: Weak<Mutex<MacWindowState>>,
1911    drag_id: usize,
1912    event: MouseMoveEvent,
1913) {
1914    loop {
1915        Timer::after(Duration::from_millis(16)).await;
1916        if let Some(window_state) = window_state.upgrade() {
1917            let mut lock = window_state.lock();
1918            if lock.synthetic_drag_counter == drag_id {
1919                if let Some(mut callback) = lock.event_callback.take() {
1920                    drop(lock);
1921                    callback(PlatformInput::MouseMove(event.clone()));
1922                    window_state.lock().event_callback = Some(callback);
1923                }
1924            } else {
1925                break;
1926            }
1927        }
1928    }
1929}
1930
1931fn send_new_event(window_state_lock: &Mutex<MacWindowState>, e: PlatformInput) -> bool {
1932    let window_state = window_state_lock.lock().event_callback.take();
1933    if let Some(mut callback) = window_state {
1934        callback(e);
1935        window_state_lock.lock().event_callback = Some(callback);
1936        true
1937    } else {
1938        false
1939    }
1940}
1941
1942fn drag_event_position(window_state: &Mutex<MacWindowState>, dragging_info: id) -> Point<Pixels> {
1943    let drag_location: NSPoint = unsafe { msg_send![dragging_info, draggingLocation] };
1944    convert_mouse_position(drag_location, window_state.lock().content_size().height)
1945}
1946
1947fn with_input_handler<F, R>(window: &Object, f: F) -> Option<R>
1948where
1949    F: FnOnce(&mut PlatformInputHandler) -> R,
1950{
1951    let window_state = unsafe { get_window_state(window) };
1952    let mut lock = window_state.as_ref().lock();
1953    if let Some(mut input_handler) = lock.input_handler.take() {
1954        drop(lock);
1955        let result = f(&mut input_handler);
1956        window_state.lock().input_handler = Some(input_handler);
1957        Some(result)
1958    } else {
1959        None
1960    }
1961}
1962
1963unsafe fn display_id_for_screen(screen: id) -> CGDirectDisplayID {
1964    let device_description = NSScreen::deviceDescription(screen);
1965    let screen_number_key: id = NSString::alloc(nil).init_str("NSScreenNumber");
1966    let screen_number = device_description.objectForKey_(screen_number_key);
1967    let screen_number: NSUInteger = msg_send![screen_number, unsignedIntegerValue];
1968    screen_number as CGDirectDisplayID
1969}