events.rs

   1use std::rc::Rc;
   2
   3use ::util::ResultExt;
   4use anyhow::Context as _;
   5use windows::{
   6    Win32::{
   7        Foundation::*,
   8        Graphics::Gdi::*,
   9        System::SystemServices::*,
  10        UI::{
  11            Controls::*,
  12            HiDpi::*,
  13            Input::{Ime::*, KeyboardAndMouse::*},
  14            WindowsAndMessaging::*,
  15        },
  16    },
  17    core::PCWSTR,
  18};
  19
  20use crate::*;
  21use gpui::*;
  22
  23pub(crate) const WM_GPUI_CURSOR_STYLE_CHANGED: u32 = WM_USER + 1;
  24pub(crate) const WM_GPUI_CLOSE_ONE_WINDOW: u32 = WM_USER + 2;
  25pub(crate) const WM_GPUI_TASK_DISPATCHED_ON_MAIN_THREAD: u32 = WM_USER + 3;
  26pub(crate) const WM_GPUI_DOCK_MENU_ACTION: u32 = WM_USER + 4;
  27pub(crate) const WM_GPUI_FORCE_UPDATE_WINDOW: u32 = WM_USER + 5;
  28pub(crate) const WM_GPUI_KEYBOARD_LAYOUT_CHANGED: u32 = WM_USER + 6;
  29pub(crate) const WM_GPUI_GPU_DEVICE_LOST: u32 = WM_USER + 7;
  30pub(crate) const WM_GPUI_KEYDOWN: u32 = WM_USER + 8;
  31
  32const SIZE_MOVE_LOOP_TIMER_ID: usize = 1;
  33
  34impl WindowsWindowInner {
  35    pub(crate) fn handle_msg(
  36        self: &Rc<Self>,
  37        handle: HWND,
  38        msg: u32,
  39        wparam: WPARAM,
  40        lparam: LPARAM,
  41    ) -> LRESULT {
  42        let handled = match msg {
  43            // eagerly activate the window, so calls to `active_window` will work correctly
  44            WM_MOUSEACTIVATE => {
  45                unsafe { SetActiveWindow(handle).ok() };
  46                None
  47            }
  48            WM_ACTIVATE => self.handle_activate_msg(wparam),
  49            WM_CREATE => self.handle_create_msg(handle),
  50            WM_MOVE => self.handle_move_msg(handle, lparam),
  51            WM_SIZE => self.handle_size_msg(wparam, lparam),
  52            WM_GETMINMAXINFO => self.handle_get_min_max_info_msg(lparam),
  53            WM_ENTERSIZEMOVE | WM_ENTERMENULOOP => self.handle_size_move_loop(handle),
  54            WM_EXITSIZEMOVE | WM_EXITMENULOOP => self.handle_size_move_loop_exit(handle),
  55            WM_TIMER => self.handle_timer_msg(handle, wparam),
  56            WM_NCCALCSIZE => self.handle_calc_client_size(handle, wparam, lparam),
  57            WM_DPICHANGED => self.handle_dpi_changed_msg(handle, wparam, lparam),
  58            WM_DISPLAYCHANGE => self.handle_display_change_msg(handle),
  59            WM_NCHITTEST => self.handle_hit_test_msg(handle, lparam),
  60            WM_PAINT => self.handle_paint_msg(handle),
  61            WM_CLOSE => self.handle_close_msg(),
  62            WM_DESTROY => self.handle_destroy_msg(handle),
  63            WM_MOUSEMOVE => self.handle_mouse_move_msg(handle, lparam, wparam),
  64            WM_MOUSELEAVE | WM_NCMOUSELEAVE => self.handle_mouse_leave_msg(),
  65            WM_NCMOUSEMOVE => self.handle_nc_mouse_move_msg(handle, lparam),
  66            // Treat double click as a second single click, since we track the double clicks ourselves.
  67            // If you don't interact with any elements, this will fall through to the windows default
  68            // behavior of toggling whether the window is maximized.
  69            WM_NCLBUTTONDBLCLK | WM_NCLBUTTONDOWN => {
  70                self.handle_nc_mouse_down_msg(handle, MouseButton::Left, wparam, lparam)
  71            }
  72            WM_NCRBUTTONDOWN => {
  73                self.handle_nc_mouse_down_msg(handle, MouseButton::Right, wparam, lparam)
  74            }
  75            WM_NCMBUTTONDOWN => {
  76                self.handle_nc_mouse_down_msg(handle, MouseButton::Middle, wparam, lparam)
  77            }
  78            WM_NCLBUTTONUP => {
  79                self.handle_nc_mouse_up_msg(handle, MouseButton::Left, wparam, lparam)
  80            }
  81            WM_NCRBUTTONUP => {
  82                self.handle_nc_mouse_up_msg(handle, MouseButton::Right, wparam, lparam)
  83            }
  84            WM_NCMBUTTONUP => {
  85                self.handle_nc_mouse_up_msg(handle, MouseButton::Middle, wparam, lparam)
  86            }
  87            WM_LBUTTONDOWN => self.handle_mouse_down_msg(handle, MouseButton::Left, lparam),
  88            WM_RBUTTONDOWN => self.handle_mouse_down_msg(handle, MouseButton::Right, lparam),
  89            WM_MBUTTONDOWN => self.handle_mouse_down_msg(handle, MouseButton::Middle, lparam),
  90            WM_XBUTTONDOWN => {
  91                self.handle_xbutton_msg(handle, wparam, lparam, Self::handle_mouse_down_msg)
  92            }
  93            WM_LBUTTONUP => self.handle_mouse_up_msg(handle, MouseButton::Left, lparam),
  94            WM_RBUTTONUP => self.handle_mouse_up_msg(handle, MouseButton::Right, lparam),
  95            WM_MBUTTONUP => self.handle_mouse_up_msg(handle, MouseButton::Middle, lparam),
  96            WM_XBUTTONUP => {
  97                self.handle_xbutton_msg(handle, wparam, lparam, Self::handle_mouse_up_msg)
  98            }
  99            WM_MOUSEWHEEL => self.handle_mouse_wheel_msg(handle, wparam, lparam),
 100            WM_MOUSEHWHEEL => self.handle_mouse_horizontal_wheel_msg(handle, wparam, lparam),
 101            WM_SYSKEYUP => self.handle_syskeyup_msg(wparam, lparam),
 102            WM_KEYUP => self.handle_keyup_msg(wparam, lparam),
 103            WM_GPUI_KEYDOWN => self.handle_keydown_msg(wparam, lparam),
 104            WM_CHAR => self.handle_char_msg(wparam),
 105            WM_IME_STARTCOMPOSITION => self.handle_ime_position(handle),
 106            WM_IME_COMPOSITION => self.handle_ime_composition(handle, lparam),
 107            WM_SETCURSOR => self.handle_set_cursor(handle, lparam),
 108            WM_SETTINGCHANGE => self.handle_system_settings_changed(handle, wparam, lparam),
 109            WM_INPUTLANGCHANGE => self.handle_input_language_changed(),
 110            WM_SHOWWINDOW => self.handle_window_visibility_changed(handle, wparam),
 111            WM_GPUI_CURSOR_STYLE_CHANGED => self.handle_cursor_changed(lparam),
 112            WM_GPUI_FORCE_UPDATE_WINDOW => self.draw_window(handle, true),
 113            WM_GPUI_GPU_DEVICE_LOST => self.handle_device_lost(lparam),
 114            DM_POINTERHITTEST => self.handle_dm_pointer_hit_test(wparam),
 115            _ => None,
 116        };
 117        if let Some(n) = handled {
 118            LRESULT(n)
 119        } else {
 120            unsafe { DefWindowProcW(handle, msg, wparam, lparam) }
 121        }
 122    }
 123
 124    fn handle_move_msg(&self, handle: HWND, lparam: LPARAM) -> Option<isize> {
 125        let origin = logical_point(
 126            lparam.signed_loword() as f32,
 127            lparam.signed_hiword() as f32,
 128            self.state.scale_factor.get(),
 129        );
 130        self.state.origin.set(origin);
 131        let size = self.state.logical_size.get();
 132        let center_x = origin.x.as_f32() + size.width.as_f32() / 2.;
 133        let center_y = origin.y.as_f32() + size.height.as_f32() / 2.;
 134        let monitor_bounds = self.state.display.get().bounds();
 135        if center_x < monitor_bounds.left().as_f32()
 136            || center_x > monitor_bounds.right().as_f32()
 137            || center_y < monitor_bounds.top().as_f32()
 138            || center_y > monitor_bounds.bottom().as_f32()
 139        {
 140            // center of the window may have moved to another monitor
 141            let monitor = unsafe { MonitorFromWindow(handle, MONITOR_DEFAULTTONULL) };
 142            // minimize the window can trigger this event too, in this case,
 143            // monitor is invalid, we do nothing.
 144            if !monitor.is_invalid() && self.state.display.get().handle != monitor {
 145                // we will get the same monitor if we only have one
 146                self.state
 147                    .display
 148                    .set(WindowsDisplay::new_with_handle(monitor).log_err()?);
 149            }
 150        }
 151        if let Some(mut callback) = self.state.callbacks.moved.take() {
 152            callback();
 153            self.state.callbacks.moved.set(Some(callback));
 154        }
 155        Some(0)
 156    }
 157
 158    fn handle_get_min_max_info_msg(&self, lparam: LPARAM) -> Option<isize> {
 159        let min_size = self.state.min_size?;
 160        let scale_factor = self.state.scale_factor.get();
 161        let boarder_offset = &self.state.border_offset;
 162
 163        unsafe {
 164            let minmax_info = &mut *(lparam.0 as *mut MINMAXINFO);
 165            minmax_info.ptMinTrackSize.x = min_size.width.scale(scale_factor).as_f32() as i32
 166                + boarder_offset.width_offset.get();
 167            minmax_info.ptMinTrackSize.y = min_size.height.scale(scale_factor).as_f32() as i32
 168                + boarder_offset.height_offset.get();
 169        }
 170        Some(0)
 171    }
 172
 173    fn handle_size_msg(&self, wparam: WPARAM, lparam: LPARAM) -> Option<isize> {
 174        // Don't resize the renderer when the window is minimized, but record that it was minimized so
 175        // that on restore the swap chain can be recreated via `update_drawable_size_even_if_unchanged`.
 176        if wparam.0 == SIZE_MINIMIZED as usize {
 177            self.state
 178                .restore_from_minimized
 179                .set(self.state.callbacks.request_frame.take());
 180            return Some(0);
 181        }
 182
 183        let width = lparam.loword().max(1) as i32;
 184        let height = lparam.hiword().max(1) as i32;
 185        let new_size = size(DevicePixels(width), DevicePixels(height));
 186
 187        let scale_factor = self.state.scale_factor.get();
 188        let mut should_resize_renderer = false;
 189        if let Some(restore_from_minimized) = self.state.restore_from_minimized.take() {
 190            self.state
 191                .callbacks
 192                .request_frame
 193                .set(Some(restore_from_minimized));
 194        } else {
 195            should_resize_renderer = true;
 196        }
 197
 198        self.handle_size_change(new_size, scale_factor, should_resize_renderer);
 199        Some(0)
 200    }
 201
 202    fn handle_size_change(
 203        &self,
 204        device_size: Size<DevicePixels>,
 205        scale_factor: f32,
 206        should_resize_renderer: bool,
 207    ) {
 208        let new_logical_size = device_size.to_pixels(scale_factor);
 209
 210        self.state.logical_size.set(new_logical_size);
 211        if should_resize_renderer
 212            && let Err(e) = self.state.renderer.borrow_mut().resize(device_size)
 213        {
 214            log::error!("Failed to resize renderer, invalidating devices: {}", e);
 215            self.state
 216                .invalidate_devices
 217                .store(true, std::sync::atomic::Ordering::Release);
 218        }
 219        if let Some(mut callback) = self.state.callbacks.resize.take() {
 220            callback(new_logical_size, scale_factor);
 221            self.state.callbacks.resize.set(Some(callback));
 222        }
 223    }
 224
 225    fn handle_size_move_loop(&self, handle: HWND) -> Option<isize> {
 226        unsafe {
 227            let ret = SetTimer(
 228                Some(handle),
 229                SIZE_MOVE_LOOP_TIMER_ID,
 230                USER_TIMER_MINIMUM,
 231                None,
 232            );
 233            if ret == 0 {
 234                log::error!(
 235                    "unable to create timer: {}",
 236                    std::io::Error::last_os_error()
 237                );
 238            }
 239        }
 240        None
 241    }
 242
 243    fn handle_size_move_loop_exit(&self, handle: HWND) -> Option<isize> {
 244        unsafe {
 245            KillTimer(Some(handle), SIZE_MOVE_LOOP_TIMER_ID).log_err();
 246        }
 247        None
 248    }
 249
 250    fn handle_timer_msg(&self, handle: HWND, wparam: WPARAM) -> Option<isize> {
 251        if wparam.0 == SIZE_MOVE_LOOP_TIMER_ID {
 252            let mut runnables = self.main_receiver.clone().try_iter();
 253            while let Some(Ok(runnable)) = runnables.next() {
 254                WindowsDispatcher::execute_runnable(runnable);
 255            }
 256            self.handle_paint_msg(handle)
 257        } else {
 258            None
 259        }
 260    }
 261
 262    fn handle_paint_msg(&self, handle: HWND) -> Option<isize> {
 263        self.draw_window(handle, false)
 264    }
 265
 266    fn handle_close_msg(&self) -> Option<isize> {
 267        let mut callback = self.state.callbacks.should_close.take()?;
 268        let should_close = callback();
 269        self.state.callbacks.should_close.set(Some(callback));
 270        if should_close { None } else { Some(0) }
 271    }
 272
 273    fn handle_destroy_msg(&self, handle: HWND) -> Option<isize> {
 274        let callback = { self.state.callbacks.close.take() };
 275        // Re-enable parent window if this was a modal dialog
 276        if let Some(parent_hwnd) = self.parent_hwnd {
 277            unsafe {
 278                let _ = EnableWindow(parent_hwnd, true);
 279                let _ = SetForegroundWindow(parent_hwnd);
 280            }
 281        }
 282
 283        if let Some(callback) = callback {
 284            callback();
 285        }
 286        unsafe {
 287            PostMessageW(
 288                Some(self.platform_window_handle),
 289                WM_GPUI_CLOSE_ONE_WINDOW,
 290                WPARAM(self.validation_number),
 291                LPARAM(handle.0 as isize),
 292            )
 293            .log_err();
 294        }
 295        Some(0)
 296    }
 297
 298    fn handle_mouse_move_msg(&self, handle: HWND, lparam: LPARAM, wparam: WPARAM) -> Option<isize> {
 299        self.start_tracking_mouse(handle, TME_LEAVE);
 300
 301        let Some(mut func) = self.state.callbacks.input.take() else {
 302            return Some(1);
 303        };
 304        let scale_factor = self.state.scale_factor.get();
 305
 306        let pressed_button = match MODIFIERKEYS_FLAGS(wparam.loword() as u32) {
 307            flags if flags.contains(MK_LBUTTON) => Some(MouseButton::Left),
 308            flags if flags.contains(MK_RBUTTON) => Some(MouseButton::Right),
 309            flags if flags.contains(MK_MBUTTON) => Some(MouseButton::Middle),
 310            flags if flags.contains(MK_XBUTTON1) => {
 311                Some(MouseButton::Navigate(NavigationDirection::Back))
 312            }
 313            flags if flags.contains(MK_XBUTTON2) => {
 314                Some(MouseButton::Navigate(NavigationDirection::Forward))
 315            }
 316            _ => None,
 317        };
 318        let x = lparam.signed_loword() as f32;
 319        let y = lparam.signed_hiword() as f32;
 320        let input = PlatformInput::MouseMove(MouseMoveEvent {
 321            position: logical_point(x, y, scale_factor),
 322            pressed_button,
 323            modifiers: current_modifiers(),
 324        });
 325        let handled = !func(input).propagate;
 326        self.state.callbacks.input.set(Some(func));
 327
 328        if handled { Some(0) } else { Some(1) }
 329    }
 330
 331    fn handle_mouse_leave_msg(&self) -> Option<isize> {
 332        self.state.hovered.set(false);
 333        if let Some(mut callback) = self.state.callbacks.hovered_status_change.take() {
 334            callback(false);
 335            self.state
 336                .callbacks
 337                .hovered_status_change
 338                .set(Some(callback));
 339        }
 340
 341        Some(0)
 342    }
 343
 344    fn handle_syskeyup_msg(&self, wparam: WPARAM, lparam: LPARAM) -> Option<isize> {
 345        let input = handle_key_event(wparam, lparam, &self.state, |keystroke, _| {
 346            PlatformInput::KeyUp(KeyUpEvent { keystroke })
 347        })?;
 348        let mut func = self.state.callbacks.input.take()?;
 349
 350        func(input);
 351        self.state.callbacks.input.set(Some(func));
 352
 353        // Always return 0 to indicate that the message was handled, so we could properly handle `ModifiersChanged` event.
 354        Some(0)
 355    }
 356
 357    // It's a known bug that you can't trigger `ctrl-shift-0`. See:
 358    // https://superuser.com/questions/1455762/ctrl-shift-number-key-combination-has-stopped-working-for-a-few-numbers
 359    fn handle_keydown_msg(&self, wparam: WPARAM, lparam: LPARAM) -> Option<isize> {
 360        let Some(input) = handle_key_event(
 361            wparam,
 362            lparam,
 363            &self.state,
 364            |keystroke, prefer_character_input| {
 365                PlatformInput::KeyDown(KeyDownEvent {
 366                    keystroke,
 367                    is_held: lparam.0 & (0x1 << 30) > 0,
 368                    prefer_character_input,
 369                })
 370            },
 371        ) else {
 372            return Some(1);
 373        };
 374
 375        let Some(mut func) = self.state.callbacks.input.take() else {
 376            return Some(1);
 377        };
 378
 379        let handled = !func(input).propagate;
 380
 381        self.state.callbacks.input.set(Some(func));
 382
 383        if handled { Some(0) } else { Some(1) }
 384    }
 385
 386    fn handle_keyup_msg(&self, wparam: WPARAM, lparam: LPARAM) -> Option<isize> {
 387        let Some(input) = handle_key_event(wparam, lparam, &self.state, |keystroke, _| {
 388            PlatformInput::KeyUp(KeyUpEvent { keystroke })
 389        }) else {
 390            return Some(1);
 391        };
 392
 393        let Some(mut func) = self.state.callbacks.input.take() else {
 394            return Some(1);
 395        };
 396
 397        let handled = !func(input).propagate;
 398        self.state.callbacks.input.set(Some(func));
 399
 400        if handled { Some(0) } else { Some(1) }
 401    }
 402
 403    fn handle_char_msg(&self, wparam: WPARAM) -> Option<isize> {
 404        let input = self.parse_char_message(wparam)?;
 405        self.with_input_handler(|input_handler| {
 406            input_handler.replace_text_in_range(None, &input);
 407        });
 408
 409        Some(0)
 410    }
 411
 412    fn handle_mouse_down_msg(
 413        &self,
 414        handle: HWND,
 415        button: MouseButton,
 416        lparam: LPARAM,
 417    ) -> Option<isize> {
 418        unsafe { SetCapture(handle) };
 419
 420        let Some(mut func) = self.state.callbacks.input.take() else {
 421            return Some(1);
 422        };
 423        let x = lparam.signed_loword();
 424        let y = lparam.signed_hiword();
 425        let physical_point = point(DevicePixels(x as i32), DevicePixels(y as i32));
 426        let click_count = self.state.click_state.update(button, physical_point);
 427        let scale_factor = self.state.scale_factor.get();
 428
 429        let input = PlatformInput::MouseDown(MouseDownEvent {
 430            button,
 431            position: logical_point(x as f32, y as f32, scale_factor),
 432            modifiers: current_modifiers(),
 433            click_count,
 434            first_mouse: false,
 435        });
 436        let handled = !func(input).propagate;
 437        self.state.callbacks.input.set(Some(func));
 438
 439        if handled { Some(0) } else { Some(1) }
 440    }
 441
 442    fn handle_mouse_up_msg(
 443        &self,
 444        _handle: HWND,
 445        button: MouseButton,
 446        lparam: LPARAM,
 447    ) -> Option<isize> {
 448        unsafe { ReleaseCapture().log_err() };
 449
 450        let Some(mut func) = self.state.callbacks.input.take() else {
 451            return Some(1);
 452        };
 453        let x = lparam.signed_loword() as f32;
 454        let y = lparam.signed_hiword() as f32;
 455        let click_count = self.state.click_state.current_count.get();
 456        let scale_factor = self.state.scale_factor.get();
 457
 458        let input = PlatformInput::MouseUp(MouseUpEvent {
 459            button,
 460            position: logical_point(x, y, scale_factor),
 461            modifiers: current_modifiers(),
 462            click_count,
 463        });
 464        let handled = !func(input).propagate;
 465        self.state.callbacks.input.set(Some(func));
 466
 467        if handled { Some(0) } else { Some(1) }
 468    }
 469
 470    fn handle_xbutton_msg(
 471        &self,
 472        handle: HWND,
 473        wparam: WPARAM,
 474        lparam: LPARAM,
 475        handler: impl Fn(&Self, HWND, MouseButton, LPARAM) -> Option<isize>,
 476    ) -> Option<isize> {
 477        let nav_dir = match wparam.hiword() {
 478            XBUTTON1 => NavigationDirection::Back,
 479            XBUTTON2 => NavigationDirection::Forward,
 480            _ => return Some(1),
 481        };
 482        handler(self, handle, MouseButton::Navigate(nav_dir), lparam)
 483    }
 484
 485    fn handle_mouse_wheel_msg(
 486        &self,
 487        handle: HWND,
 488        wparam: WPARAM,
 489        lparam: LPARAM,
 490    ) -> Option<isize> {
 491        let modifiers = current_modifiers();
 492
 493        let Some(mut func) = self.state.callbacks.input.take() else {
 494            return Some(1);
 495        };
 496        let scale_factor = self.state.scale_factor.get();
 497        let wheel_scroll_amount = match modifiers.shift {
 498            true => self
 499                .system_settings()
 500                .mouse_wheel_settings
 501                .wheel_scroll_chars
 502                .get(),
 503            false => self
 504                .system_settings()
 505                .mouse_wheel_settings
 506                .wheel_scroll_lines
 507                .get(),
 508        };
 509
 510        let wheel_distance =
 511            (wparam.signed_hiword() as f32 / WHEEL_DELTA as f32) * wheel_scroll_amount as f32;
 512        let mut cursor_point = POINT {
 513            x: lparam.signed_loword().into(),
 514            y: lparam.signed_hiword().into(),
 515        };
 516        unsafe { ScreenToClient(handle, &mut cursor_point).ok().log_err() };
 517        let input = PlatformInput::ScrollWheel(ScrollWheelEvent {
 518            position: logical_point(cursor_point.x as f32, cursor_point.y as f32, scale_factor),
 519            delta: ScrollDelta::Lines(match modifiers.shift {
 520                true => Point {
 521                    x: wheel_distance,
 522                    y: 0.0,
 523                },
 524                false => Point {
 525                    y: wheel_distance,
 526                    x: 0.0,
 527                },
 528            }),
 529            modifiers,
 530            touch_phase: TouchPhase::Moved,
 531        });
 532        let handled = !func(input).propagate;
 533        self.state.callbacks.input.set(Some(func));
 534
 535        if handled { Some(0) } else { Some(1) }
 536    }
 537
 538    fn handle_mouse_horizontal_wheel_msg(
 539        &self,
 540        handle: HWND,
 541        wparam: WPARAM,
 542        lparam: LPARAM,
 543    ) -> Option<isize> {
 544        let Some(mut func) = self.state.callbacks.input.take() else {
 545            return Some(1);
 546        };
 547        let scale_factor = self.state.scale_factor.get();
 548        let wheel_scroll_chars = self
 549            .system_settings()
 550            .mouse_wheel_settings
 551            .wheel_scroll_chars
 552            .get();
 553
 554        let wheel_distance =
 555            (-wparam.signed_hiword() as f32 / WHEEL_DELTA as f32) * wheel_scroll_chars as f32;
 556        let mut cursor_point = POINT {
 557            x: lparam.signed_loword().into(),
 558            y: lparam.signed_hiword().into(),
 559        };
 560        unsafe { ScreenToClient(handle, &mut cursor_point).ok().log_err() };
 561        let event = PlatformInput::ScrollWheel(ScrollWheelEvent {
 562            position: logical_point(cursor_point.x as f32, cursor_point.y as f32, scale_factor),
 563            delta: ScrollDelta::Lines(Point {
 564                x: wheel_distance,
 565                y: 0.0,
 566            }),
 567            modifiers: current_modifiers(),
 568            touch_phase: TouchPhase::Moved,
 569        });
 570        let handled = !func(event).propagate;
 571        self.state.callbacks.input.set(Some(func));
 572
 573        if handled { Some(0) } else { Some(1) }
 574    }
 575
 576    fn retrieve_caret_position(&self) -> Option<POINT> {
 577        self.with_input_handler_and_scale_factor(|input_handler, scale_factor| {
 578            let caret_range = input_handler.selected_text_range(false)?;
 579            let caret_position = input_handler.bounds_for_range(caret_range.range)?;
 580            Some(POINT {
 581                // logical to physical
 582                x: (caret_position.origin.x.as_f32() * scale_factor) as i32,
 583                y: (caret_position.origin.y.as_f32() * scale_factor) as i32
 584                    + ((caret_position.size.height.as_f32() * scale_factor) as i32 / 2),
 585            })
 586        })
 587    }
 588
 589    fn handle_ime_position(&self, handle: HWND) -> Option<isize> {
 590        if let Some(caret_position) = self.retrieve_caret_position() {
 591            self.update_ime_position(handle, caret_position);
 592        }
 593        Some(0)
 594    }
 595
 596    pub(crate) fn update_ime_position(&self, handle: HWND, caret_position: POINT) {
 597        let Some(ctx) = ImeContext::get(handle) else {
 598            return;
 599        };
 600        unsafe {
 601            ImmSetCompositionWindow(
 602                *ctx,
 603                &COMPOSITIONFORM {
 604                    dwStyle: CFS_POINT,
 605                    ptCurrentPos: caret_position,
 606                    ..Default::default()
 607                },
 608            )
 609            .ok()
 610            .log_err();
 611
 612            ImmSetCandidateWindow(
 613                *ctx,
 614                &CANDIDATEFORM {
 615                    dwStyle: CFS_CANDIDATEPOS,
 616                    ptCurrentPos: caret_position,
 617                    ..Default::default()
 618                },
 619            )
 620            .ok()
 621            .log_err();
 622        }
 623    }
 624
 625    fn update_ime_enabled(&self, handle: HWND) {
 626        let ime_enabled = self
 627            .with_input_handler(|input_handler| input_handler.query_accepts_text_input())
 628            .unwrap_or(false);
 629        if ime_enabled == self.state.ime_enabled.get() {
 630            return;
 631        }
 632        self.state.ime_enabled.set(ime_enabled);
 633        unsafe {
 634            if ime_enabled {
 635                ImmAssociateContextEx(handle, HIMC::default(), IACE_DEFAULT)
 636                    .ok()
 637                    .log_err();
 638            } else {
 639                if let Some(ctx) = ImeContext::get(handle) {
 640                    ImmNotifyIME(*ctx, NI_COMPOSITIONSTR, CPS_COMPLETE, 0)
 641                        .ok()
 642                        .log_err();
 643                }
 644                ImmAssociateContextEx(handle, HIMC::default(), 0)
 645                    .ok()
 646                    .log_err();
 647            }
 648        }
 649    }
 650
 651    fn handle_ime_composition(&self, handle: HWND, lparam: LPARAM) -> Option<isize> {
 652        let ctx = ImeContext::get(handle)?;
 653        self.handle_ime_composition_inner(*ctx, lparam)
 654    }
 655
 656    fn handle_ime_composition_inner(&self, ctx: HIMC, lparam: LPARAM) -> Option<isize> {
 657        let lparam = lparam.0 as u32;
 658        if lparam == 0 {
 659            // Japanese IME may send this message with lparam = 0, which indicates that
 660            // there is no composition string.
 661            self.with_input_handler(|input_handler| {
 662                input_handler.replace_text_in_range(None, "");
 663            })?;
 664            Some(0)
 665        } else {
 666            if lparam & GCS_RESULTSTR.0 > 0 {
 667                let comp_result = parse_ime_composition_string(ctx, GCS_RESULTSTR)?;
 668                self.with_input_handler(|input_handler| {
 669                    input_handler
 670                        .replace_text_in_range(None, &String::from_utf16_lossy(&comp_result));
 671                })?;
 672            }
 673            if lparam & GCS_COMPSTR.0 > 0 {
 674                let comp_string = parse_ime_composition_string(ctx, GCS_COMPSTR)?;
 675                let caret_pos =
 676                    (!comp_string.is_empty() && lparam & GCS_CURSORPOS.0 > 0).then(|| {
 677                        let cursor_pos = retrieve_composition_cursor_position(ctx);
 678                        let pos = if should_use_ime_cursor_position(ctx, cursor_pos) {
 679                            cursor_pos
 680                        } else {
 681                            comp_string.len()
 682                        };
 683                        pos..pos
 684                    });
 685                self.with_input_handler(|input_handler| {
 686                    input_handler.replace_and_mark_text_in_range(
 687                        None,
 688                        &String::from_utf16_lossy(&comp_string),
 689                        caret_pos,
 690                    );
 691                })?;
 692            }
 693            if lparam & (GCS_RESULTSTR.0 | GCS_COMPSTR.0) > 0 {
 694                return Some(0);
 695            }
 696
 697            // currently, we don't care other stuff
 698            None
 699        }
 700    }
 701
 702    fn handle_calc_client_size(
 703        &self,
 704        handle: HWND,
 705        wparam: WPARAM,
 706        lparam: LPARAM,
 707    ) -> Option<isize> {
 708        if !self.hide_title_bar || self.state.is_fullscreen() || wparam.0 == 0 {
 709            return None;
 710        }
 711
 712        unsafe {
 713            let params = lparam.0 as *mut NCCALCSIZE_PARAMS;
 714            let saved_top = (*params).rgrc[0].top;
 715            let result = DefWindowProcW(handle, WM_NCCALCSIZE, wparam, lparam);
 716            (*params).rgrc[0].top = saved_top;
 717            if self.state.is_maximized() {
 718                let dpi = GetDpiForWindow(handle);
 719                (*params).rgrc[0].top += get_frame_thicknessx(dpi);
 720            }
 721            Some(result.0 as isize)
 722        }
 723    }
 724
 725    fn handle_activate_msg(self: &Rc<Self>, wparam: WPARAM) -> Option<isize> {
 726        let activated = wparam.loword() > 0;
 727        let this = self.clone();
 728
 729        // When the window is activated (gains focus), reset the modifier tracking state.
 730        // This fixes the issue where Alt-Tab away and back leaves stale modifier state
 731        // (especially the Alt key) because Windows doesn't always send key-up events to
 732        // windows that have lost focus.
 733        if activated {
 734            this.state.last_reported_modifiers.set(None);
 735            this.state.last_reported_capslock.set(None);
 736
 737            if let Some(mut func) = this.state.callbacks.input.take() {
 738                let input = PlatformInput::ModifiersChanged(ModifiersChangedEvent {
 739                    modifiers: current_modifiers(),
 740                    capslock: current_capslock(),
 741                });
 742                func(input);
 743                this.state.callbacks.input.set(Some(func));
 744            }
 745        }
 746
 747        self.executor
 748            .spawn(async move {
 749                if let Some(mut func) = this.state.callbacks.active_status_change.take() {
 750                    func(activated);
 751                    this.state.callbacks.active_status_change.set(Some(func));
 752                }
 753            })
 754            .detach();
 755
 756        None
 757    }
 758
 759    fn handle_create_msg(&self, handle: HWND) -> Option<isize> {
 760        if self.hide_title_bar {
 761            notify_frame_changed(handle);
 762            Some(0)
 763        } else {
 764            None
 765        }
 766    }
 767
 768    fn handle_dpi_changed_msg(
 769        &self,
 770        handle: HWND,
 771        wparam: WPARAM,
 772        lparam: LPARAM,
 773    ) -> Option<isize> {
 774        let new_dpi = wparam.loword() as f32;
 775
 776        let is_maximized = self.state.is_maximized();
 777        let new_scale_factor = new_dpi / USER_DEFAULT_SCREEN_DPI as f32;
 778        self.state.scale_factor.set(new_scale_factor);
 779        self.state.border_offset.update(handle).log_err();
 780
 781        self.state
 782            .direct_manipulation
 783            .set_scale_factor(new_scale_factor);
 784
 785        if is_maximized {
 786            // Get the monitor and its work area at the new DPI
 787            let monitor = unsafe { MonitorFromWindow(handle, MONITOR_DEFAULTTONEAREST) };
 788            let mut monitor_info: MONITORINFO = unsafe { std::mem::zeroed() };
 789            monitor_info.cbSize = std::mem::size_of::<MONITORINFO>() as u32;
 790            if unsafe { GetMonitorInfoW(monitor, &mut monitor_info) }.as_bool() {
 791                let work_area = monitor_info.rcWork;
 792                let width = work_area.right - work_area.left;
 793                let height = work_area.bottom - work_area.top;
 794
 795                // Update the window size to match the new monitor work area
 796                // This will trigger WM_SIZE which will handle the size change
 797                unsafe {
 798                    SetWindowPos(
 799                        handle,
 800                        None,
 801                        work_area.left,
 802                        work_area.top,
 803                        width,
 804                        height,
 805                        SWP_NOZORDER | SWP_NOACTIVATE | SWP_FRAMECHANGED,
 806                    )
 807                    .context("unable to set maximized window position after dpi has changed")
 808                    .log_err();
 809                }
 810
 811                // SetWindowPos may not send WM_SIZE for maximized windows in some cases,
 812                // so we manually update the size to ensure proper rendering
 813                let device_size = size(DevicePixels(width), DevicePixels(height));
 814                self.handle_size_change(device_size, new_scale_factor, true);
 815            }
 816        } else {
 817            // For non-maximized windows, use the suggested RECT from the system
 818            let rect = unsafe { &*(lparam.0 as *const RECT) };
 819            let width = rect.right - rect.left;
 820            let height = rect.bottom - rect.top;
 821            // this will emit `WM_SIZE` and `WM_MOVE` right here
 822            // even before this function returns
 823            // the new size is handled in `WM_SIZE`
 824            unsafe {
 825                SetWindowPos(
 826                    handle,
 827                    None,
 828                    rect.left,
 829                    rect.top,
 830                    width,
 831                    height,
 832                    SWP_NOZORDER | SWP_NOACTIVATE,
 833                )
 834                .context("unable to set window position after dpi has changed")
 835                .log_err();
 836            }
 837        }
 838
 839        Some(0)
 840    }
 841
 842    fn handle_display_change_msg(&self, handle: HWND) -> Option<isize> {
 843        let new_monitor = unsafe { MonitorFromWindow(handle, MONITOR_DEFAULTTONULL) };
 844        if new_monitor.is_invalid() {
 845            log::error!("No monitor detected!");
 846            return None;
 847        }
 848        let new_display = WindowsDisplay::new_with_handle(new_monitor).log_err()?;
 849        self.state.display.set(new_display);
 850        Some(0)
 851    }
 852
 853    fn handle_hit_test_msg(&self, handle: HWND, lparam: LPARAM) -> Option<isize> {
 854        if !self.is_movable || self.state.is_fullscreen() {
 855            return None;
 856        }
 857
 858        let callback = self.state.callbacks.hit_test_window_control.take();
 859        let drag_area = if let Some(mut callback) = callback {
 860            let area = callback();
 861            self.state
 862                .callbacks
 863                .hit_test_window_control
 864                .set(Some(callback));
 865            if let Some(area) = area {
 866                match area {
 867                    WindowControlArea::Drag => Some(HTCAPTION as _),
 868                    WindowControlArea::Close => return Some(HTCLOSE as _),
 869                    WindowControlArea::Max => return Some(HTMAXBUTTON as _),
 870                    WindowControlArea::Min => return Some(HTMINBUTTON as _),
 871                }
 872            } else {
 873                None
 874            }
 875        } else {
 876            None
 877        };
 878
 879        if !self.hide_title_bar {
 880            // If the OS draws the title bar, we don't need to handle hit test messages.
 881            return drag_area;
 882        }
 883
 884        let dpi = unsafe { GetDpiForWindow(handle) };
 885        // We do not use the OS title bar, so the default `DefWindowProcW` will only register a 1px edge for resizes
 886        // We need to calculate the frame thickness ourselves and do the hit test manually.
 887        let frame_y = get_frame_thicknessx(dpi);
 888        let frame_x = get_frame_thicknessy(dpi);
 889        let mut cursor_point = POINT {
 890            x: lparam.signed_loword().into(),
 891            y: lparam.signed_hiword().into(),
 892        };
 893
 894        unsafe { ScreenToClient(handle, &mut cursor_point).ok().log_err() };
 895        if !self.state.is_maximized() && 0 <= cursor_point.y && cursor_point.y <= frame_y {
 896            // x-axis actually goes from -frame_x to 0
 897            return Some(if cursor_point.x <= 0 {
 898                HTTOPLEFT
 899            } else {
 900                let mut rect = Default::default();
 901                unsafe { GetWindowRect(handle, &mut rect) }.log_err();
 902                // right and bottom bounds of RECT are exclusive, thus `-1`
 903                let right = rect.right - rect.left - 1;
 904                // the bounds include the padding frames, so accomodate for both of them
 905                if right - 2 * frame_x <= cursor_point.x {
 906                    HTTOPRIGHT
 907                } else {
 908                    HTTOP
 909                }
 910            } as _);
 911        }
 912
 913        drag_area
 914    }
 915
 916    fn handle_nc_mouse_move_msg(&self, handle: HWND, lparam: LPARAM) -> Option<isize> {
 917        self.start_tracking_mouse(handle, TME_LEAVE | TME_NONCLIENT);
 918
 919        let mut func = self.state.callbacks.input.take()?;
 920        let scale_factor = self.state.scale_factor.get();
 921
 922        let mut cursor_point = POINT {
 923            x: lparam.signed_loword().into(),
 924            y: lparam.signed_hiword().into(),
 925        };
 926        unsafe { ScreenToClient(handle, &mut cursor_point).ok().log_err() };
 927        let input = PlatformInput::MouseMove(MouseMoveEvent {
 928            position: logical_point(cursor_point.x as f32, cursor_point.y as f32, scale_factor),
 929            pressed_button: None,
 930            modifiers: current_modifiers(),
 931        });
 932        let handled = !func(input).propagate;
 933        self.state.callbacks.input.set(Some(func));
 934
 935        if handled { Some(0) } else { None }
 936    }
 937
 938    fn handle_nc_mouse_down_msg(
 939        &self,
 940        handle: HWND,
 941        button: MouseButton,
 942        wparam: WPARAM,
 943        lparam: LPARAM,
 944    ) -> Option<isize> {
 945        if let Some(mut func) = self.state.callbacks.input.take() {
 946            let scale_factor = self.state.scale_factor.get();
 947            let mut cursor_point = POINT {
 948                x: lparam.signed_loword().into(),
 949                y: lparam.signed_hiword().into(),
 950            };
 951            unsafe { ScreenToClient(handle, &mut cursor_point).ok().log_err() };
 952            let physical_point = point(DevicePixels(cursor_point.x), DevicePixels(cursor_point.y));
 953            let click_count = self.state.click_state.update(button, physical_point);
 954
 955            let input = PlatformInput::MouseDown(MouseDownEvent {
 956                button,
 957                position: logical_point(cursor_point.x as f32, cursor_point.y as f32, scale_factor),
 958                modifiers: current_modifiers(),
 959                click_count,
 960                first_mouse: false,
 961            });
 962            let handled = !func(input).propagate;
 963            self.state.callbacks.input.set(Some(func));
 964
 965            if handled {
 966                return Some(0);
 967            }
 968        } else {
 969        };
 970
 971        // Since these are handled in handle_nc_mouse_up_msg we must prevent the default window proc
 972        if button == MouseButton::Left {
 973            match wparam.0 as u32 {
 974                HTMINBUTTON => self.state.nc_button_pressed.set(Some(HTMINBUTTON)),
 975                HTMAXBUTTON => self.state.nc_button_pressed.set(Some(HTMAXBUTTON)),
 976                HTCLOSE => self.state.nc_button_pressed.set(Some(HTCLOSE)),
 977                _ => return None,
 978            };
 979            Some(0)
 980        } else {
 981            None
 982        }
 983    }
 984
 985    fn handle_nc_mouse_up_msg(
 986        &self,
 987        handle: HWND,
 988        button: MouseButton,
 989        wparam: WPARAM,
 990        lparam: LPARAM,
 991    ) -> Option<isize> {
 992        if let Some(mut func) = self.state.callbacks.input.take() {
 993            let scale_factor = self.state.scale_factor.get();
 994
 995            let mut cursor_point = POINT {
 996                x: lparam.signed_loword().into(),
 997                y: lparam.signed_hiword().into(),
 998            };
 999            unsafe { ScreenToClient(handle, &mut cursor_point).ok().log_err() };
1000            let input = PlatformInput::MouseUp(MouseUpEvent {
1001                button,
1002                position: logical_point(cursor_point.x as f32, cursor_point.y as f32, scale_factor),
1003                modifiers: current_modifiers(),
1004                click_count: 1,
1005            });
1006            let handled = !func(input).propagate;
1007            self.state.callbacks.input.set(Some(func));
1008
1009            if handled {
1010                return Some(0);
1011            }
1012        } else {
1013        }
1014
1015        let last_pressed = self.state.nc_button_pressed.take();
1016        if button == MouseButton::Left
1017            && let Some(last_pressed) = last_pressed
1018        {
1019            let handled = match (wparam.0 as u32, last_pressed) {
1020                (HTMINBUTTON, HTMINBUTTON) => {
1021                    unsafe { ShowWindowAsync(handle, SW_MINIMIZE).ok().log_err() };
1022                    true
1023                }
1024                (HTMAXBUTTON, HTMAXBUTTON) => {
1025                    if self.state.is_maximized() {
1026                        unsafe { ShowWindowAsync(handle, SW_NORMAL).ok().log_err() };
1027                    } else {
1028                        unsafe { ShowWindowAsync(handle, SW_MAXIMIZE).ok().log_err() };
1029                    }
1030                    true
1031                }
1032                (HTCLOSE, HTCLOSE) => {
1033                    unsafe {
1034                        PostMessageW(Some(handle), WM_CLOSE, WPARAM::default(), LPARAM::default())
1035                            .log_err()
1036                    };
1037                    true
1038                }
1039                _ => false,
1040            };
1041            if handled {
1042                return Some(0);
1043            }
1044        }
1045
1046        None
1047    }
1048
1049    fn handle_cursor_changed(&self, lparam: LPARAM) -> Option<isize> {
1050        let had_cursor = self.state.current_cursor.get().is_some();
1051
1052        self.state.current_cursor.set(if lparam.0 == 0 {
1053            None
1054        } else {
1055            Some(HCURSOR(lparam.0 as _))
1056        });
1057
1058        if had_cursor != self.state.current_cursor.get().is_some() {
1059            unsafe { SetCursor(self.state.current_cursor.get()) };
1060        }
1061
1062        Some(0)
1063    }
1064
1065    fn handle_set_cursor(&self, handle: HWND, lparam: LPARAM) -> Option<isize> {
1066        if unsafe { !IsWindowEnabled(handle).as_bool() }
1067            || matches!(
1068                lparam.loword() as u32,
1069                HTLEFT
1070                    | HTRIGHT
1071                    | HTTOP
1072                    | HTTOPLEFT
1073                    | HTTOPRIGHT
1074                    | HTBOTTOM
1075                    | HTBOTTOMLEFT
1076                    | HTBOTTOMRIGHT
1077            )
1078        {
1079            return None;
1080        }
1081        unsafe {
1082            SetCursor(self.state.current_cursor.get());
1083        };
1084        Some(0)
1085    }
1086
1087    fn handle_system_settings_changed(
1088        &self,
1089        handle: HWND,
1090        wparam: WPARAM,
1091        lparam: LPARAM,
1092    ) -> Option<isize> {
1093        if wparam.0 != 0 {
1094            self.state.click_state.system_update(wparam.0);
1095            self.state.border_offset.update(handle).log_err();
1096            // system settings may emit a window message which wants to take the refcell self.state, so drop it
1097
1098            self.system_settings().update(wparam.0);
1099        } else {
1100            self.handle_system_theme_changed(handle, lparam)?;
1101        };
1102
1103        Some(0)
1104    }
1105
1106    fn handle_system_theme_changed(&self, handle: HWND, lparam: LPARAM) -> Option<isize> {
1107        // lParam is a pointer to a string that indicates the area containing the system parameter
1108        // that was changed.
1109        let parameter = PCWSTR::from_raw(lparam.0 as _);
1110        if unsafe { !parameter.is_null() && !parameter.is_empty() }
1111            && let Some(parameter_string) = unsafe { parameter.to_string() }.log_err()
1112        {
1113            log::info!("System settings changed: {}", parameter_string);
1114            if parameter_string.as_str() == "ImmersiveColorSet" {
1115                let new_appearance = system_appearance()
1116                    .context("unable to get system appearance when handling ImmersiveColorSet")
1117                    .log_err()?;
1118
1119                if new_appearance != self.state.appearance.get() {
1120                    self.state.appearance.set(new_appearance);
1121                    let mut callback = self.state.callbacks.appearance_changed.take()?;
1122
1123                    callback();
1124                    self.state.callbacks.appearance_changed.set(Some(callback));
1125                    configure_dwm_dark_mode(handle, new_appearance);
1126                }
1127            }
1128        }
1129        Some(0)
1130    }
1131
1132    fn handle_input_language_changed(&self) -> Option<isize> {
1133        unsafe {
1134            PostMessageW(
1135                Some(self.platform_window_handle),
1136                WM_GPUI_KEYBOARD_LAYOUT_CHANGED,
1137                WPARAM(self.validation_number),
1138                LPARAM(0),
1139            )
1140            .log_err();
1141        }
1142        Some(0)
1143    }
1144
1145    fn handle_window_visibility_changed(&self, handle: HWND, wparam: WPARAM) -> Option<isize> {
1146        if wparam.0 == 1 {
1147            self.draw_window(handle, false);
1148        }
1149        None
1150    }
1151
1152    fn handle_device_lost(&self, lparam: LPARAM) -> Option<isize> {
1153        let devices = lparam.0 as *const DirectXDevices;
1154        let devices = unsafe { &*devices };
1155        if let Err(err) = self
1156            .state
1157            .renderer
1158            .borrow_mut()
1159            .handle_device_lost(&devices)
1160        {
1161            panic!("Device lost: {err}");
1162        }
1163        Some(0)
1164    }
1165
1166    fn handle_dm_pointer_hit_test(&self, wparam: WPARAM) -> Option<isize> {
1167        self.state.direct_manipulation.on_pointer_hit_test(wparam);
1168        None
1169    }
1170
1171    #[inline]
1172    fn draw_window(&self, handle: HWND, force_render: bool) -> Option<isize> {
1173        let mut request_frame = self.state.callbacks.request_frame.take()?;
1174
1175        self.state.direct_manipulation.update();
1176
1177        let events = self.state.direct_manipulation.drain_events();
1178        if !events.is_empty() {
1179            if let Some(mut func) = self.state.callbacks.input.take() {
1180                for event in events {
1181                    func(event);
1182                }
1183                self.state.callbacks.input.set(Some(func));
1184            }
1185        }
1186
1187        if force_render {
1188            // Re-enable drawing after a device loss recovery. The forced render
1189            // will rebuild the scene with fresh atlas textures.
1190            self.state.renderer.borrow_mut().mark_drawable();
1191        }
1192        request_frame(RequestFrameOptions {
1193            require_presentation: false,
1194            force_render,
1195        });
1196
1197        self.state.callbacks.request_frame.set(Some(request_frame));
1198        self.update_ime_enabled(handle);
1199        unsafe { ValidateRect(Some(handle), None).ok().log_err() };
1200
1201        Some(0)
1202    }
1203
1204    #[inline]
1205    fn parse_char_message(&self, wparam: WPARAM) -> Option<String> {
1206        let code_point = wparam.loword();
1207
1208        // https://www.unicode.org/versions/Unicode16.0.0/core-spec/chapter-3/#G2630
1209        match code_point {
1210            0xD800..=0xDBFF => {
1211                // High surrogate, wait for low surrogate
1212                self.state.pending_surrogate.set(Some(code_point));
1213                None
1214            }
1215            0xDC00..=0xDFFF => {
1216                if let Some(high_surrogate) = self.state.pending_surrogate.take() {
1217                    // Low surrogate, combine with pending high surrogate
1218                    String::from_utf16(&[high_surrogate, code_point]).ok()
1219                } else {
1220                    // Invalid low surrogate without a preceding high surrogate
1221                    log::warn!(
1222                        "Received low surrogate without a preceding high surrogate: {code_point:x}"
1223                    );
1224                    None
1225                }
1226            }
1227            _ => {
1228                self.state.pending_surrogate.set(None);
1229                char::from_u32(code_point as u32)
1230                    .filter(|c| !c.is_control())
1231                    .map(|c| c.to_string())
1232            }
1233        }
1234    }
1235
1236    fn start_tracking_mouse(&self, handle: HWND, flags: TRACKMOUSEEVENT_FLAGS) {
1237        if !self.state.hovered.get() {
1238            self.state.hovered.set(true);
1239            unsafe {
1240                TrackMouseEvent(&mut TRACKMOUSEEVENT {
1241                    cbSize: std::mem::size_of::<TRACKMOUSEEVENT>() as u32,
1242                    dwFlags: flags,
1243                    hwndTrack: handle,
1244                    dwHoverTime: HOVER_DEFAULT,
1245                })
1246                .log_err()
1247            };
1248            if let Some(mut callback) = self.state.callbacks.hovered_status_change.take() {
1249                callback(true);
1250                self.state
1251                    .callbacks
1252                    .hovered_status_change
1253                    .set(Some(callback));
1254            }
1255        }
1256    }
1257
1258    fn with_input_handler<F, R>(&self, f: F) -> Option<R>
1259    where
1260        F: FnOnce(&mut PlatformInputHandler) -> R,
1261    {
1262        let mut input_handler = self.state.input_handler.take()?;
1263        let result = f(&mut input_handler);
1264        self.state.input_handler.set(Some(input_handler));
1265        Some(result)
1266    }
1267
1268    fn with_input_handler_and_scale_factor<F, R>(&self, f: F) -> Option<R>
1269    where
1270        F: FnOnce(&mut PlatformInputHandler, f32) -> Option<R>,
1271    {
1272        let mut input_handler = self.state.input_handler.take()?;
1273        let scale_factor = self.state.scale_factor.get();
1274
1275        let result = f(&mut input_handler, scale_factor);
1276        self.state.input_handler.set(Some(input_handler));
1277        result
1278    }
1279}
1280
1281struct ImeContext {
1282    hwnd: HWND,
1283    himc: HIMC,
1284}
1285
1286impl ImeContext {
1287    fn get(hwnd: HWND) -> Option<Self> {
1288        let himc = unsafe { ImmGetContext(hwnd) };
1289        if himc.is_invalid() {
1290            return None;
1291        }
1292        Some(Self { hwnd, himc })
1293    }
1294}
1295
1296impl std::ops::Deref for ImeContext {
1297    type Target = HIMC;
1298    fn deref(&self) -> &HIMC {
1299        &self.himc
1300    }
1301}
1302
1303impl Drop for ImeContext {
1304    fn drop(&mut self) {
1305        unsafe {
1306            ImmReleaseContext(self.hwnd, self.himc).ok().log_err();
1307        }
1308    }
1309}
1310
1311fn handle_key_event<F>(
1312    wparam: WPARAM,
1313    lparam: LPARAM,
1314    state: &WindowsWindowState,
1315    f: F,
1316) -> Option<PlatformInput>
1317where
1318    F: FnOnce(Keystroke, bool) -> PlatformInput,
1319{
1320    let virtual_key = VIRTUAL_KEY(wparam.loword());
1321    let modifiers = current_modifiers();
1322
1323    match virtual_key {
1324        VK_SHIFT | VK_CONTROL | VK_MENU | VK_LMENU | VK_RMENU | VK_LWIN | VK_RWIN => {
1325            if state
1326                .last_reported_modifiers
1327                .get()
1328                .is_some_and(|prev_modifiers| prev_modifiers == modifiers)
1329            {
1330                return None;
1331            }
1332            state.last_reported_modifiers.set(Some(modifiers));
1333            Some(PlatformInput::ModifiersChanged(ModifiersChangedEvent {
1334                modifiers,
1335                capslock: current_capslock(),
1336            }))
1337        }
1338        VK_PACKET => None,
1339        VK_CAPITAL => {
1340            let capslock = current_capslock();
1341            if state
1342                .last_reported_capslock
1343                .get()
1344                .is_some_and(|prev_capslock| prev_capslock == capslock)
1345            {
1346                return None;
1347            }
1348            state.last_reported_capslock.set(Some(capslock));
1349            Some(PlatformInput::ModifiersChanged(ModifiersChangedEvent {
1350                modifiers,
1351                capslock,
1352            }))
1353        }
1354        vkey => {
1355            let keystroke = parse_normal_key(vkey, lparam, modifiers)?;
1356            Some(f(keystroke.0, keystroke.1))
1357        }
1358    }
1359}
1360
1361fn parse_immutable(vkey: VIRTUAL_KEY) -> Option<String> {
1362    Some(
1363        match vkey {
1364            VK_SPACE => "space",
1365            VK_BACK => "backspace",
1366            VK_RETURN => "enter",
1367            VK_TAB => "tab",
1368            VK_UP => "up",
1369            VK_DOWN => "down",
1370            VK_RIGHT => "right",
1371            VK_LEFT => "left",
1372            VK_HOME => "home",
1373            VK_END => "end",
1374            VK_PRIOR => "pageup",
1375            VK_NEXT => "pagedown",
1376            VK_BROWSER_BACK => "back",
1377            VK_BROWSER_FORWARD => "forward",
1378            VK_ESCAPE => "escape",
1379            VK_INSERT => "insert",
1380            VK_DELETE => "delete",
1381            VK_APPS => "menu",
1382            VK_F1 => "f1",
1383            VK_F2 => "f2",
1384            VK_F3 => "f3",
1385            VK_F4 => "f4",
1386            VK_F5 => "f5",
1387            VK_F6 => "f6",
1388            VK_F7 => "f7",
1389            VK_F8 => "f8",
1390            VK_F9 => "f9",
1391            VK_F10 => "f10",
1392            VK_F11 => "f11",
1393            VK_F12 => "f12",
1394            VK_F13 => "f13",
1395            VK_F14 => "f14",
1396            VK_F15 => "f15",
1397            VK_F16 => "f16",
1398            VK_F17 => "f17",
1399            VK_F18 => "f18",
1400            VK_F19 => "f19",
1401            VK_F20 => "f20",
1402            VK_F21 => "f21",
1403            VK_F22 => "f22",
1404            VK_F23 => "f23",
1405            VK_F24 => "f24",
1406            _ => return None,
1407        }
1408        .to_string(),
1409    )
1410}
1411
1412fn parse_normal_key(
1413    vkey: VIRTUAL_KEY,
1414    lparam: LPARAM,
1415    mut modifiers: Modifiers,
1416) -> Option<(Keystroke, bool)> {
1417    let (key_char, prefer_character_input) = process_key(vkey, lparam.hiword());
1418
1419    let key = parse_immutable(vkey).or_else(|| {
1420        let scan_code = lparam.hiword() & 0xFF;
1421        get_keystroke_key(vkey, scan_code as u32, &mut modifiers)
1422    })?;
1423
1424    Some((
1425        Keystroke {
1426            modifiers,
1427            key,
1428            key_char,
1429        },
1430        prefer_character_input,
1431    ))
1432}
1433
1434fn process_key(vkey: VIRTUAL_KEY, scan_code: u16) -> (Option<String>, bool) {
1435    let mut keyboard_state = [0u8; 256];
1436    unsafe {
1437        if GetKeyboardState(&mut keyboard_state).is_err() {
1438            return (None, false);
1439        }
1440    }
1441
1442    let mut buffer_c = [0u16; 8];
1443    let result_c = unsafe {
1444        ToUnicode(
1445            vkey.0 as u32,
1446            scan_code as u32,
1447            Some(&keyboard_state),
1448            &mut buffer_c,
1449            0x4,
1450        )
1451    };
1452
1453    if result_c == 0 {
1454        return (None, false);
1455    }
1456
1457    let c = &buffer_c[..result_c.unsigned_abs() as usize];
1458    let key_char = String::from_utf16(c)
1459        .ok()
1460        .filter(|s| !s.is_empty() && !s.chars().next().unwrap().is_control());
1461
1462    if result_c < 0 {
1463        return (key_char, true);
1464    }
1465
1466    if key_char.is_none() {
1467        return (None, false);
1468    }
1469
1470    // Workaround for some bug that makes the compiler think keyboard_state is still zeroed out
1471    let keyboard_state = std::hint::black_box(keyboard_state);
1472    let ctrl_down = (keyboard_state[VK_CONTROL.0 as usize] & 0x80) != 0;
1473    let alt_down = (keyboard_state[VK_MENU.0 as usize] & 0x80) != 0;
1474    let win_down = (keyboard_state[VK_LWIN.0 as usize] & 0x80) != 0
1475        || (keyboard_state[VK_RWIN.0 as usize] & 0x80) != 0;
1476
1477    let has_modifiers = ctrl_down || alt_down || win_down;
1478    if !has_modifiers {
1479        return (key_char, false);
1480    }
1481
1482    let mut state_no_modifiers = keyboard_state;
1483    state_no_modifiers[VK_CONTROL.0 as usize] = 0;
1484    state_no_modifiers[VK_LCONTROL.0 as usize] = 0;
1485    state_no_modifiers[VK_RCONTROL.0 as usize] = 0;
1486    state_no_modifiers[VK_MENU.0 as usize] = 0;
1487    state_no_modifiers[VK_LMENU.0 as usize] = 0;
1488    state_no_modifiers[VK_RMENU.0 as usize] = 0;
1489    state_no_modifiers[VK_LWIN.0 as usize] = 0;
1490    state_no_modifiers[VK_RWIN.0 as usize] = 0;
1491
1492    let mut buffer_c_no_modifiers = [0u16; 8];
1493    let result_c_no_modifiers = unsafe {
1494        ToUnicode(
1495            vkey.0 as u32,
1496            scan_code as u32,
1497            Some(&state_no_modifiers),
1498            &mut buffer_c_no_modifiers,
1499            0x4,
1500        )
1501    };
1502
1503    let c_no_modifiers = &buffer_c_no_modifiers[..result_c_no_modifiers.unsigned_abs() as usize];
1504    (
1505        key_char,
1506        result_c != result_c_no_modifiers || c != c_no_modifiers,
1507    )
1508}
1509
1510fn parse_ime_composition_string(ctx: HIMC, comp_type: IME_COMPOSITION_STRING) -> Option<Vec<u16>> {
1511    unsafe {
1512        let string_len = ImmGetCompositionStringW(ctx, comp_type, None, 0);
1513        if string_len >= 0 {
1514            let mut buffer = vec![0u8; string_len as usize + 2];
1515            ImmGetCompositionStringW(
1516                ctx,
1517                comp_type,
1518                Some(buffer.as_mut_ptr() as _),
1519                string_len as _,
1520            );
1521            let wstring = std::slice::from_raw_parts::<u16>(
1522                buffer.as_mut_ptr().cast::<u16>(),
1523                string_len as usize / 2,
1524            );
1525            Some(wstring.to_vec())
1526        } else {
1527            None
1528        }
1529    }
1530}
1531
1532#[inline]
1533fn retrieve_composition_cursor_position(ctx: HIMC) -> usize {
1534    unsafe { ImmGetCompositionStringW(ctx, GCS_CURSORPOS, None, 0) as usize }
1535}
1536
1537fn should_use_ime_cursor_position(ctx: HIMC, cursor_pos: usize) -> bool {
1538    let attrs_size = unsafe { ImmGetCompositionStringW(ctx, GCS_COMPATTR, None, 0) } as usize;
1539    if attrs_size == 0 {
1540        return false;
1541    }
1542
1543    let mut attrs = vec![0u8; attrs_size];
1544    let result = unsafe {
1545        ImmGetCompositionStringW(
1546            ctx,
1547            GCS_COMPATTR,
1548            Some(attrs.as_mut_ptr() as *mut _),
1549            attrs_size as u32,
1550        )
1551    };
1552    if result <= 0 {
1553        return false;
1554    }
1555
1556    // Keep the cursor adjacent to the inserted text by only using the suggested position
1557    // if it's adjacent to unconverted text.
1558    let at_cursor_is_input = cursor_pos < attrs.len() && attrs[cursor_pos] == (ATTR_INPUT as u8);
1559    let before_cursor_is_input = cursor_pos > 0
1560        && (cursor_pos - 1) < attrs.len()
1561        && attrs[cursor_pos - 1] == (ATTR_INPUT as u8);
1562
1563    at_cursor_is_input || before_cursor_is_input
1564}
1565
1566#[inline]
1567fn is_virtual_key_pressed(vkey: VIRTUAL_KEY) -> bool {
1568    unsafe { GetKeyState(vkey.0 as i32) < 0 }
1569}
1570
1571#[inline]
1572pub(crate) fn current_modifiers() -> Modifiers {
1573    Modifiers {
1574        control: is_virtual_key_pressed(VK_CONTROL),
1575        alt: is_virtual_key_pressed(VK_MENU),
1576        shift: is_virtual_key_pressed(VK_SHIFT),
1577        platform: is_virtual_key_pressed(VK_LWIN) || is_virtual_key_pressed(VK_RWIN),
1578        function: false,
1579    }
1580}
1581
1582#[inline]
1583pub(crate) fn current_capslock() -> Capslock {
1584    let on = unsafe { GetKeyState(VK_CAPITAL.0 as i32) & 1 } > 0;
1585    Capslock { on }
1586}
1587
1588// there is some additional non-visible space when talking about window
1589// borders on Windows:
1590// - SM_CXSIZEFRAME: The resize handle.
1591// - SM_CXPADDEDBORDER: Additional border space that isn't part of the resize handle.
1592fn get_frame_thicknessx(dpi: u32) -> i32 {
1593    let resize_frame_thickness = unsafe { GetSystemMetricsForDpi(SM_CXSIZEFRAME, dpi) };
1594    let padding_thickness = unsafe { GetSystemMetricsForDpi(SM_CXPADDEDBORDER, dpi) };
1595    resize_frame_thickness + padding_thickness
1596}
1597
1598fn get_frame_thicknessy(dpi: u32) -> i32 {
1599    let resize_frame_thickness = unsafe { GetSystemMetricsForDpi(SM_CYSIZEFRAME, dpi) };
1600    let padding_thickness = unsafe { GetSystemMetricsForDpi(SM_CXPADDEDBORDER, dpi) };
1601    resize_frame_thickness + padding_thickness
1602}
1603
1604fn notify_frame_changed(handle: HWND) {
1605    unsafe {
1606        SetWindowPos(
1607            handle,
1608            None,
1609            0,
1610            0,
1611            0,
1612            0,
1613            SWP_FRAMECHANGED
1614                | SWP_NOACTIVATE
1615                | SWP_NOCOPYBITS
1616                | SWP_NOMOVE
1617                | SWP_NOOWNERZORDER
1618                | SWP_NOREPOSITION
1619                | SWP_NOSENDCHANGING
1620                | SWP_NOSIZE
1621                | SWP_NOZORDER,
1622        )
1623        .log_err();
1624    }
1625}