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        self.executor
 729            .spawn(async move {
 730                if let Some(mut func) = this.state.callbacks.active_status_change.take() {
 731                    func(activated);
 732                    this.state.callbacks.active_status_change.set(Some(func));
 733                }
 734            })
 735            .detach();
 736
 737        None
 738    }
 739
 740    fn handle_create_msg(&self, handle: HWND) -> Option<isize> {
 741        if self.hide_title_bar {
 742            notify_frame_changed(handle);
 743            Some(0)
 744        } else {
 745            None
 746        }
 747    }
 748
 749    fn handle_dpi_changed_msg(
 750        &self,
 751        handle: HWND,
 752        wparam: WPARAM,
 753        lparam: LPARAM,
 754    ) -> Option<isize> {
 755        let new_dpi = wparam.loword() as f32;
 756
 757        let is_maximized = self.state.is_maximized();
 758        let new_scale_factor = new_dpi / USER_DEFAULT_SCREEN_DPI as f32;
 759        self.state.scale_factor.set(new_scale_factor);
 760        self.state.border_offset.update(handle).log_err();
 761
 762        self.state
 763            .direct_manipulation
 764            .set_scale_factor(new_scale_factor);
 765
 766        if is_maximized {
 767            // Get the monitor and its work area at the new DPI
 768            let monitor = unsafe { MonitorFromWindow(handle, MONITOR_DEFAULTTONEAREST) };
 769            let mut monitor_info: MONITORINFO = unsafe { std::mem::zeroed() };
 770            monitor_info.cbSize = std::mem::size_of::<MONITORINFO>() as u32;
 771            if unsafe { GetMonitorInfoW(monitor, &mut monitor_info) }.as_bool() {
 772                let work_area = monitor_info.rcWork;
 773                let width = work_area.right - work_area.left;
 774                let height = work_area.bottom - work_area.top;
 775
 776                // Update the window size to match the new monitor work area
 777                // This will trigger WM_SIZE which will handle the size change
 778                unsafe {
 779                    SetWindowPos(
 780                        handle,
 781                        None,
 782                        work_area.left,
 783                        work_area.top,
 784                        width,
 785                        height,
 786                        SWP_NOZORDER | SWP_NOACTIVATE | SWP_FRAMECHANGED,
 787                    )
 788                    .context("unable to set maximized window position after dpi has changed")
 789                    .log_err();
 790                }
 791
 792                // SetWindowPos may not send WM_SIZE for maximized windows in some cases,
 793                // so we manually update the size to ensure proper rendering
 794                let device_size = size(DevicePixels(width), DevicePixels(height));
 795                self.handle_size_change(device_size, new_scale_factor, true);
 796            }
 797        } else {
 798            // For non-maximized windows, use the suggested RECT from the system
 799            let rect = unsafe { &*(lparam.0 as *const RECT) };
 800            let width = rect.right - rect.left;
 801            let height = rect.bottom - rect.top;
 802            // this will emit `WM_SIZE` and `WM_MOVE` right here
 803            // even before this function returns
 804            // the new size is handled in `WM_SIZE`
 805            unsafe {
 806                SetWindowPos(
 807                    handle,
 808                    None,
 809                    rect.left,
 810                    rect.top,
 811                    width,
 812                    height,
 813                    SWP_NOZORDER | SWP_NOACTIVATE,
 814                )
 815                .context("unable to set window position after dpi has changed")
 816                .log_err();
 817            }
 818        }
 819
 820        Some(0)
 821    }
 822
 823    fn handle_display_change_msg(&self, handle: HWND) -> Option<isize> {
 824        let new_monitor = unsafe { MonitorFromWindow(handle, MONITOR_DEFAULTTONULL) };
 825        if new_monitor.is_invalid() {
 826            log::error!("No monitor detected!");
 827            return None;
 828        }
 829        let new_display = WindowsDisplay::new_with_handle(new_monitor).log_err()?;
 830        self.state.display.set(new_display);
 831        Some(0)
 832    }
 833
 834    fn handle_hit_test_msg(&self, handle: HWND, lparam: LPARAM) -> Option<isize> {
 835        if !self.is_movable || self.state.is_fullscreen() {
 836            return None;
 837        }
 838
 839        let callback = self.state.callbacks.hit_test_window_control.take();
 840        let drag_area = if let Some(mut callback) = callback {
 841            let area = callback();
 842            self.state
 843                .callbacks
 844                .hit_test_window_control
 845                .set(Some(callback));
 846            if let Some(area) = area {
 847                match area {
 848                    WindowControlArea::Drag => Some(HTCAPTION as _),
 849                    WindowControlArea::Close => return Some(HTCLOSE as _),
 850                    WindowControlArea::Max => return Some(HTMAXBUTTON as _),
 851                    WindowControlArea::Min => return Some(HTMINBUTTON as _),
 852                }
 853            } else {
 854                None
 855            }
 856        } else {
 857            None
 858        };
 859
 860        if !self.hide_title_bar {
 861            // If the OS draws the title bar, we don't need to handle hit test messages.
 862            return drag_area;
 863        }
 864
 865        let dpi = unsafe { GetDpiForWindow(handle) };
 866        // We do not use the OS title bar, so the default `DefWindowProcW` will only register a 1px edge for resizes
 867        // We need to calculate the frame thickness ourselves and do the hit test manually.
 868        let frame_y = get_frame_thicknessx(dpi);
 869        let frame_x = get_frame_thicknessy(dpi);
 870        let mut cursor_point = POINT {
 871            x: lparam.signed_loword().into(),
 872            y: lparam.signed_hiword().into(),
 873        };
 874
 875        unsafe { ScreenToClient(handle, &mut cursor_point).ok().log_err() };
 876        if !self.state.is_maximized() && 0 <= cursor_point.y && cursor_point.y <= frame_y {
 877            // x-axis actually goes from -frame_x to 0
 878            return Some(if cursor_point.x <= 0 {
 879                HTTOPLEFT
 880            } else {
 881                let mut rect = Default::default();
 882                unsafe { GetWindowRect(handle, &mut rect) }.log_err();
 883                // right and bottom bounds of RECT are exclusive, thus `-1`
 884                let right = rect.right - rect.left - 1;
 885                // the bounds include the padding frames, so accomodate for both of them
 886                if right - 2 * frame_x <= cursor_point.x {
 887                    HTTOPRIGHT
 888                } else {
 889                    HTTOP
 890                }
 891            } as _);
 892        }
 893
 894        drag_area
 895    }
 896
 897    fn handle_nc_mouse_move_msg(&self, handle: HWND, lparam: LPARAM) -> Option<isize> {
 898        self.start_tracking_mouse(handle, TME_LEAVE | TME_NONCLIENT);
 899
 900        let mut func = self.state.callbacks.input.take()?;
 901        let scale_factor = self.state.scale_factor.get();
 902
 903        let mut cursor_point = POINT {
 904            x: lparam.signed_loword().into(),
 905            y: lparam.signed_hiword().into(),
 906        };
 907        unsafe { ScreenToClient(handle, &mut cursor_point).ok().log_err() };
 908        let input = PlatformInput::MouseMove(MouseMoveEvent {
 909            position: logical_point(cursor_point.x as f32, cursor_point.y as f32, scale_factor),
 910            pressed_button: None,
 911            modifiers: current_modifiers(),
 912        });
 913        let handled = !func(input).propagate;
 914        self.state.callbacks.input.set(Some(func));
 915
 916        if handled { Some(0) } else { None }
 917    }
 918
 919    fn handle_nc_mouse_down_msg(
 920        &self,
 921        handle: HWND,
 922        button: MouseButton,
 923        wparam: WPARAM,
 924        lparam: LPARAM,
 925    ) -> Option<isize> {
 926        if let Some(mut func) = self.state.callbacks.input.take() {
 927            let scale_factor = self.state.scale_factor.get();
 928            let mut cursor_point = POINT {
 929                x: lparam.signed_loword().into(),
 930                y: lparam.signed_hiword().into(),
 931            };
 932            unsafe { ScreenToClient(handle, &mut cursor_point).ok().log_err() };
 933            let physical_point = point(DevicePixels(cursor_point.x), DevicePixels(cursor_point.y));
 934            let click_count = self.state.click_state.update(button, physical_point);
 935
 936            let input = PlatformInput::MouseDown(MouseDownEvent {
 937                button,
 938                position: logical_point(cursor_point.x as f32, cursor_point.y as f32, scale_factor),
 939                modifiers: current_modifiers(),
 940                click_count,
 941                first_mouse: false,
 942            });
 943            let handled = !func(input).propagate;
 944            self.state.callbacks.input.set(Some(func));
 945
 946            if handled {
 947                return Some(0);
 948            }
 949        } else {
 950        };
 951
 952        // Since these are handled in handle_nc_mouse_up_msg we must prevent the default window proc
 953        if button == MouseButton::Left {
 954            match wparam.0 as u32 {
 955                HTMINBUTTON => self.state.nc_button_pressed.set(Some(HTMINBUTTON)),
 956                HTMAXBUTTON => self.state.nc_button_pressed.set(Some(HTMAXBUTTON)),
 957                HTCLOSE => self.state.nc_button_pressed.set(Some(HTCLOSE)),
 958                _ => return None,
 959            };
 960            Some(0)
 961        } else {
 962            None
 963        }
 964    }
 965
 966    fn handle_nc_mouse_up_msg(
 967        &self,
 968        handle: HWND,
 969        button: MouseButton,
 970        wparam: WPARAM,
 971        lparam: LPARAM,
 972    ) -> Option<isize> {
 973        if let Some(mut func) = self.state.callbacks.input.take() {
 974            let scale_factor = self.state.scale_factor.get();
 975
 976            let mut cursor_point = POINT {
 977                x: lparam.signed_loword().into(),
 978                y: lparam.signed_hiword().into(),
 979            };
 980            unsafe { ScreenToClient(handle, &mut cursor_point).ok().log_err() };
 981            let input = PlatformInput::MouseUp(MouseUpEvent {
 982                button,
 983                position: logical_point(cursor_point.x as f32, cursor_point.y as f32, scale_factor),
 984                modifiers: current_modifiers(),
 985                click_count: 1,
 986            });
 987            let handled = !func(input).propagate;
 988            self.state.callbacks.input.set(Some(func));
 989
 990            if handled {
 991                return Some(0);
 992            }
 993        } else {
 994        }
 995
 996        let last_pressed = self.state.nc_button_pressed.take();
 997        if button == MouseButton::Left
 998            && let Some(last_pressed) = last_pressed
 999        {
1000            let handled = match (wparam.0 as u32, last_pressed) {
1001                (HTMINBUTTON, HTMINBUTTON) => {
1002                    unsafe { ShowWindowAsync(handle, SW_MINIMIZE).ok().log_err() };
1003                    true
1004                }
1005                (HTMAXBUTTON, HTMAXBUTTON) => {
1006                    if self.state.is_maximized() {
1007                        unsafe { ShowWindowAsync(handle, SW_NORMAL).ok().log_err() };
1008                    } else {
1009                        unsafe { ShowWindowAsync(handle, SW_MAXIMIZE).ok().log_err() };
1010                    }
1011                    true
1012                }
1013                (HTCLOSE, HTCLOSE) => {
1014                    unsafe {
1015                        PostMessageW(Some(handle), WM_CLOSE, WPARAM::default(), LPARAM::default())
1016                            .log_err()
1017                    };
1018                    true
1019                }
1020                _ => false,
1021            };
1022            if handled {
1023                return Some(0);
1024            }
1025        }
1026
1027        None
1028    }
1029
1030    fn handle_cursor_changed(&self, lparam: LPARAM) -> Option<isize> {
1031        let had_cursor = self.state.current_cursor.get().is_some();
1032
1033        self.state.current_cursor.set(if lparam.0 == 0 {
1034            None
1035        } else {
1036            Some(HCURSOR(lparam.0 as _))
1037        });
1038
1039        if had_cursor != self.state.current_cursor.get().is_some() {
1040            unsafe { SetCursor(self.state.current_cursor.get()) };
1041        }
1042
1043        Some(0)
1044    }
1045
1046    fn handle_set_cursor(&self, handle: HWND, lparam: LPARAM) -> Option<isize> {
1047        if unsafe { !IsWindowEnabled(handle).as_bool() }
1048            || matches!(
1049                lparam.loword() as u32,
1050                HTLEFT
1051                    | HTRIGHT
1052                    | HTTOP
1053                    | HTTOPLEFT
1054                    | HTTOPRIGHT
1055                    | HTBOTTOM
1056                    | HTBOTTOMLEFT
1057                    | HTBOTTOMRIGHT
1058            )
1059        {
1060            return None;
1061        }
1062        unsafe {
1063            SetCursor(self.state.current_cursor.get());
1064        };
1065        Some(0)
1066    }
1067
1068    fn handle_system_settings_changed(
1069        &self,
1070        handle: HWND,
1071        wparam: WPARAM,
1072        lparam: LPARAM,
1073    ) -> Option<isize> {
1074        if wparam.0 != 0 {
1075            self.state.click_state.system_update(wparam.0);
1076            self.state.border_offset.update(handle).log_err();
1077            // system settings may emit a window message which wants to take the refcell self.state, so drop it
1078
1079            self.system_settings().update(wparam.0);
1080        } else {
1081            self.handle_system_theme_changed(handle, lparam)?;
1082        };
1083
1084        Some(0)
1085    }
1086
1087    fn handle_system_theme_changed(&self, handle: HWND, lparam: LPARAM) -> Option<isize> {
1088        // lParam is a pointer to a string that indicates the area containing the system parameter
1089        // that was changed.
1090        let parameter = PCWSTR::from_raw(lparam.0 as _);
1091        if unsafe { !parameter.is_null() && !parameter.is_empty() }
1092            && let Some(parameter_string) = unsafe { parameter.to_string() }.log_err()
1093        {
1094            log::info!("System settings changed: {}", parameter_string);
1095            if parameter_string.as_str() == "ImmersiveColorSet" {
1096                let new_appearance = system_appearance()
1097                    .context("unable to get system appearance when handling ImmersiveColorSet")
1098                    .log_err()?;
1099
1100                if new_appearance != self.state.appearance.get() {
1101                    self.state.appearance.set(new_appearance);
1102                    let mut callback = self.state.callbacks.appearance_changed.take()?;
1103
1104                    callback();
1105                    self.state.callbacks.appearance_changed.set(Some(callback));
1106                    configure_dwm_dark_mode(handle, new_appearance);
1107                }
1108            }
1109        }
1110        Some(0)
1111    }
1112
1113    fn handle_input_language_changed(&self) -> Option<isize> {
1114        unsafe {
1115            PostMessageW(
1116                Some(self.platform_window_handle),
1117                WM_GPUI_KEYBOARD_LAYOUT_CHANGED,
1118                WPARAM(self.validation_number),
1119                LPARAM(0),
1120            )
1121            .log_err();
1122        }
1123        Some(0)
1124    }
1125
1126    fn handle_window_visibility_changed(&self, handle: HWND, wparam: WPARAM) -> Option<isize> {
1127        if wparam.0 == 1 {
1128            self.draw_window(handle, false);
1129        }
1130        None
1131    }
1132
1133    fn handle_device_lost(&self, lparam: LPARAM) -> Option<isize> {
1134        let devices = lparam.0 as *const DirectXDevices;
1135        let devices = unsafe { &*devices };
1136        if let Err(err) = self
1137            .state
1138            .renderer
1139            .borrow_mut()
1140            .handle_device_lost(&devices)
1141        {
1142            panic!("Device lost: {err}");
1143        }
1144        Some(0)
1145    }
1146
1147    fn handle_dm_pointer_hit_test(&self, wparam: WPARAM) -> Option<isize> {
1148        self.state.direct_manipulation.on_pointer_hit_test(wparam);
1149        None
1150    }
1151
1152    #[inline]
1153    fn draw_window(&self, handle: HWND, force_render: bool) -> Option<isize> {
1154        let mut request_frame = self.state.callbacks.request_frame.take()?;
1155
1156        self.state.direct_manipulation.update();
1157
1158        let events = self.state.direct_manipulation.drain_events();
1159        if !events.is_empty() {
1160            if let Some(mut func) = self.state.callbacks.input.take() {
1161                for event in events {
1162                    func(event);
1163                }
1164                self.state.callbacks.input.set(Some(func));
1165            }
1166        }
1167
1168        if force_render {
1169            // Re-enable drawing after a device loss recovery. The forced render
1170            // will rebuild the scene with fresh atlas textures.
1171            self.state.renderer.borrow_mut().mark_drawable();
1172        }
1173        request_frame(RequestFrameOptions {
1174            require_presentation: false,
1175            force_render,
1176        });
1177
1178        self.state.callbacks.request_frame.set(Some(request_frame));
1179        self.update_ime_enabled(handle);
1180        unsafe { ValidateRect(Some(handle), None).ok().log_err() };
1181
1182        Some(0)
1183    }
1184
1185    #[inline]
1186    fn parse_char_message(&self, wparam: WPARAM) -> Option<String> {
1187        let code_point = wparam.loword();
1188
1189        // https://www.unicode.org/versions/Unicode16.0.0/core-spec/chapter-3/#G2630
1190        match code_point {
1191            0xD800..=0xDBFF => {
1192                // High surrogate, wait for low surrogate
1193                self.state.pending_surrogate.set(Some(code_point));
1194                None
1195            }
1196            0xDC00..=0xDFFF => {
1197                if let Some(high_surrogate) = self.state.pending_surrogate.take() {
1198                    // Low surrogate, combine with pending high surrogate
1199                    String::from_utf16(&[high_surrogate, code_point]).ok()
1200                } else {
1201                    // Invalid low surrogate without a preceding high surrogate
1202                    log::warn!(
1203                        "Received low surrogate without a preceding high surrogate: {code_point:x}"
1204                    );
1205                    None
1206                }
1207            }
1208            _ => {
1209                self.state.pending_surrogate.set(None);
1210                char::from_u32(code_point as u32)
1211                    .filter(|c| !c.is_control())
1212                    .map(|c| c.to_string())
1213            }
1214        }
1215    }
1216
1217    fn start_tracking_mouse(&self, handle: HWND, flags: TRACKMOUSEEVENT_FLAGS) {
1218        if !self.state.hovered.get() {
1219            self.state.hovered.set(true);
1220            unsafe {
1221                TrackMouseEvent(&mut TRACKMOUSEEVENT {
1222                    cbSize: std::mem::size_of::<TRACKMOUSEEVENT>() as u32,
1223                    dwFlags: flags,
1224                    hwndTrack: handle,
1225                    dwHoverTime: HOVER_DEFAULT,
1226                })
1227                .log_err()
1228            };
1229            if let Some(mut callback) = self.state.callbacks.hovered_status_change.take() {
1230                callback(true);
1231                self.state
1232                    .callbacks
1233                    .hovered_status_change
1234                    .set(Some(callback));
1235            }
1236        }
1237    }
1238
1239    fn with_input_handler<F, R>(&self, f: F) -> Option<R>
1240    where
1241        F: FnOnce(&mut PlatformInputHandler) -> R,
1242    {
1243        let mut input_handler = self.state.input_handler.take()?;
1244        let result = f(&mut input_handler);
1245        self.state.input_handler.set(Some(input_handler));
1246        Some(result)
1247    }
1248
1249    fn with_input_handler_and_scale_factor<F, R>(&self, f: F) -> Option<R>
1250    where
1251        F: FnOnce(&mut PlatformInputHandler, f32) -> Option<R>,
1252    {
1253        let mut input_handler = self.state.input_handler.take()?;
1254        let scale_factor = self.state.scale_factor.get();
1255
1256        let result = f(&mut input_handler, scale_factor);
1257        self.state.input_handler.set(Some(input_handler));
1258        result
1259    }
1260}
1261
1262struct ImeContext {
1263    hwnd: HWND,
1264    himc: HIMC,
1265}
1266
1267impl ImeContext {
1268    fn get(hwnd: HWND) -> Option<Self> {
1269        let himc = unsafe { ImmGetContext(hwnd) };
1270        if himc.is_invalid() {
1271            return None;
1272        }
1273        Some(Self { hwnd, himc })
1274    }
1275}
1276
1277impl std::ops::Deref for ImeContext {
1278    type Target = HIMC;
1279    fn deref(&self) -> &HIMC {
1280        &self.himc
1281    }
1282}
1283
1284impl Drop for ImeContext {
1285    fn drop(&mut self) {
1286        unsafe {
1287            ImmReleaseContext(self.hwnd, self.himc).ok().log_err();
1288        }
1289    }
1290}
1291
1292fn handle_key_event<F>(
1293    wparam: WPARAM,
1294    lparam: LPARAM,
1295    state: &WindowsWindowState,
1296    f: F,
1297) -> Option<PlatformInput>
1298where
1299    F: FnOnce(Keystroke, bool) -> PlatformInput,
1300{
1301    let virtual_key = VIRTUAL_KEY(wparam.loword());
1302    let modifiers = current_modifiers();
1303
1304    match virtual_key {
1305        VK_SHIFT | VK_CONTROL | VK_MENU | VK_LMENU | VK_RMENU | VK_LWIN | VK_RWIN => {
1306            if state
1307                .last_reported_modifiers
1308                .get()
1309                .is_some_and(|prev_modifiers| prev_modifiers == modifiers)
1310            {
1311                return None;
1312            }
1313            state.last_reported_modifiers.set(Some(modifiers));
1314            Some(PlatformInput::ModifiersChanged(ModifiersChangedEvent {
1315                modifiers,
1316                capslock: current_capslock(),
1317            }))
1318        }
1319        VK_PACKET => None,
1320        VK_CAPITAL => {
1321            let capslock = current_capslock();
1322            if state
1323                .last_reported_capslock
1324                .get()
1325                .is_some_and(|prev_capslock| prev_capslock == capslock)
1326            {
1327                return None;
1328            }
1329            state.last_reported_capslock.set(Some(capslock));
1330            Some(PlatformInput::ModifiersChanged(ModifiersChangedEvent {
1331                modifiers,
1332                capslock,
1333            }))
1334        }
1335        vkey => {
1336            let keystroke = parse_normal_key(vkey, lparam, modifiers)?;
1337            Some(f(keystroke.0, keystroke.1))
1338        }
1339    }
1340}
1341
1342fn parse_immutable(vkey: VIRTUAL_KEY) -> Option<String> {
1343    Some(
1344        match vkey {
1345            VK_SPACE => "space",
1346            VK_BACK => "backspace",
1347            VK_RETURN => "enter",
1348            VK_TAB => "tab",
1349            VK_UP => "up",
1350            VK_DOWN => "down",
1351            VK_RIGHT => "right",
1352            VK_LEFT => "left",
1353            VK_HOME => "home",
1354            VK_END => "end",
1355            VK_PRIOR => "pageup",
1356            VK_NEXT => "pagedown",
1357            VK_BROWSER_BACK => "back",
1358            VK_BROWSER_FORWARD => "forward",
1359            VK_ESCAPE => "escape",
1360            VK_INSERT => "insert",
1361            VK_DELETE => "delete",
1362            VK_APPS => "menu",
1363            VK_F1 => "f1",
1364            VK_F2 => "f2",
1365            VK_F3 => "f3",
1366            VK_F4 => "f4",
1367            VK_F5 => "f5",
1368            VK_F6 => "f6",
1369            VK_F7 => "f7",
1370            VK_F8 => "f8",
1371            VK_F9 => "f9",
1372            VK_F10 => "f10",
1373            VK_F11 => "f11",
1374            VK_F12 => "f12",
1375            VK_F13 => "f13",
1376            VK_F14 => "f14",
1377            VK_F15 => "f15",
1378            VK_F16 => "f16",
1379            VK_F17 => "f17",
1380            VK_F18 => "f18",
1381            VK_F19 => "f19",
1382            VK_F20 => "f20",
1383            VK_F21 => "f21",
1384            VK_F22 => "f22",
1385            VK_F23 => "f23",
1386            VK_F24 => "f24",
1387            _ => return None,
1388        }
1389        .to_string(),
1390    )
1391}
1392
1393fn parse_normal_key(
1394    vkey: VIRTUAL_KEY,
1395    lparam: LPARAM,
1396    mut modifiers: Modifiers,
1397) -> Option<(Keystroke, bool)> {
1398    let (key_char, prefer_character_input) = process_key(vkey, lparam.hiword());
1399
1400    let key = parse_immutable(vkey).or_else(|| {
1401        let scan_code = lparam.hiword() & 0xFF;
1402        get_keystroke_key(vkey, scan_code as u32, &mut modifiers)
1403    })?;
1404
1405    Some((
1406        Keystroke {
1407            modifiers,
1408            key,
1409            key_char,
1410        },
1411        prefer_character_input,
1412    ))
1413}
1414
1415fn process_key(vkey: VIRTUAL_KEY, scan_code: u16) -> (Option<String>, bool) {
1416    let mut keyboard_state = [0u8; 256];
1417    unsafe {
1418        if GetKeyboardState(&mut keyboard_state).is_err() {
1419            return (None, false);
1420        }
1421    }
1422
1423    let mut buffer_c = [0u16; 8];
1424    let result_c = unsafe {
1425        ToUnicode(
1426            vkey.0 as u32,
1427            scan_code as u32,
1428            Some(&keyboard_state),
1429            &mut buffer_c,
1430            0x4,
1431        )
1432    };
1433
1434    if result_c == 0 {
1435        return (None, false);
1436    }
1437
1438    let c = &buffer_c[..result_c.unsigned_abs() as usize];
1439    let key_char = String::from_utf16(c)
1440        .ok()
1441        .filter(|s| !s.is_empty() && !s.chars().next().unwrap().is_control());
1442
1443    if result_c < 0 {
1444        return (key_char, true);
1445    }
1446
1447    if key_char.is_none() {
1448        return (None, false);
1449    }
1450
1451    // Workaround for some bug that makes the compiler think keyboard_state is still zeroed out
1452    let keyboard_state = std::hint::black_box(keyboard_state);
1453    let ctrl_down = (keyboard_state[VK_CONTROL.0 as usize] & 0x80) != 0;
1454    let alt_down = (keyboard_state[VK_MENU.0 as usize] & 0x80) != 0;
1455    let win_down = (keyboard_state[VK_LWIN.0 as usize] & 0x80) != 0
1456        || (keyboard_state[VK_RWIN.0 as usize] & 0x80) != 0;
1457
1458    let has_modifiers = ctrl_down || alt_down || win_down;
1459    if !has_modifiers {
1460        return (key_char, false);
1461    }
1462
1463    let mut state_no_modifiers = keyboard_state;
1464    state_no_modifiers[VK_CONTROL.0 as usize] = 0;
1465    state_no_modifiers[VK_LCONTROL.0 as usize] = 0;
1466    state_no_modifiers[VK_RCONTROL.0 as usize] = 0;
1467    state_no_modifiers[VK_MENU.0 as usize] = 0;
1468    state_no_modifiers[VK_LMENU.0 as usize] = 0;
1469    state_no_modifiers[VK_RMENU.0 as usize] = 0;
1470    state_no_modifiers[VK_LWIN.0 as usize] = 0;
1471    state_no_modifiers[VK_RWIN.0 as usize] = 0;
1472
1473    let mut buffer_c_no_modifiers = [0u16; 8];
1474    let result_c_no_modifiers = unsafe {
1475        ToUnicode(
1476            vkey.0 as u32,
1477            scan_code as u32,
1478            Some(&state_no_modifiers),
1479            &mut buffer_c_no_modifiers,
1480            0x4,
1481        )
1482    };
1483
1484    let c_no_modifiers = &buffer_c_no_modifiers[..result_c_no_modifiers.unsigned_abs() as usize];
1485    (
1486        key_char,
1487        result_c != result_c_no_modifiers || c != c_no_modifiers,
1488    )
1489}
1490
1491fn parse_ime_composition_string(ctx: HIMC, comp_type: IME_COMPOSITION_STRING) -> Option<Vec<u16>> {
1492    unsafe {
1493        let string_len = ImmGetCompositionStringW(ctx, comp_type, None, 0);
1494        if string_len >= 0 {
1495            let mut buffer = vec![0u8; string_len as usize + 2];
1496            ImmGetCompositionStringW(
1497                ctx,
1498                comp_type,
1499                Some(buffer.as_mut_ptr() as _),
1500                string_len as _,
1501            );
1502            let wstring = std::slice::from_raw_parts::<u16>(
1503                buffer.as_mut_ptr().cast::<u16>(),
1504                string_len as usize / 2,
1505            );
1506            Some(wstring.to_vec())
1507        } else {
1508            None
1509        }
1510    }
1511}
1512
1513#[inline]
1514fn retrieve_composition_cursor_position(ctx: HIMC) -> usize {
1515    unsafe { ImmGetCompositionStringW(ctx, GCS_CURSORPOS, None, 0) as usize }
1516}
1517
1518fn should_use_ime_cursor_position(ctx: HIMC, cursor_pos: usize) -> bool {
1519    let attrs_size = unsafe { ImmGetCompositionStringW(ctx, GCS_COMPATTR, None, 0) } as usize;
1520    if attrs_size == 0 {
1521        return false;
1522    }
1523
1524    let mut attrs = vec![0u8; attrs_size];
1525    let result = unsafe {
1526        ImmGetCompositionStringW(
1527            ctx,
1528            GCS_COMPATTR,
1529            Some(attrs.as_mut_ptr() as *mut _),
1530            attrs_size as u32,
1531        )
1532    };
1533    if result <= 0 {
1534        return false;
1535    }
1536
1537    // Keep the cursor adjacent to the inserted text by only using the suggested position
1538    // if it's adjacent to unconverted text.
1539    let at_cursor_is_input = cursor_pos < attrs.len() && attrs[cursor_pos] == (ATTR_INPUT as u8);
1540    let before_cursor_is_input = cursor_pos > 0
1541        && (cursor_pos - 1) < attrs.len()
1542        && attrs[cursor_pos - 1] == (ATTR_INPUT as u8);
1543
1544    at_cursor_is_input || before_cursor_is_input
1545}
1546
1547#[inline]
1548fn is_virtual_key_pressed(vkey: VIRTUAL_KEY) -> bool {
1549    unsafe { GetKeyState(vkey.0 as i32) < 0 }
1550}
1551
1552#[inline]
1553pub(crate) fn current_modifiers() -> Modifiers {
1554    Modifiers {
1555        control: is_virtual_key_pressed(VK_CONTROL),
1556        alt: is_virtual_key_pressed(VK_MENU),
1557        shift: is_virtual_key_pressed(VK_SHIFT),
1558        platform: is_virtual_key_pressed(VK_LWIN) || is_virtual_key_pressed(VK_RWIN),
1559        function: false,
1560    }
1561}
1562
1563#[inline]
1564pub(crate) fn current_capslock() -> Capslock {
1565    let on = unsafe { GetKeyState(VK_CAPITAL.0 as i32) & 1 } > 0;
1566    Capslock { on }
1567}
1568
1569// there is some additional non-visible space when talking about window
1570// borders on Windows:
1571// - SM_CXSIZEFRAME: The resize handle.
1572// - SM_CXPADDEDBORDER: Additional border space that isn't part of the resize handle.
1573fn get_frame_thicknessx(dpi: u32) -> i32 {
1574    let resize_frame_thickness = unsafe { GetSystemMetricsForDpi(SM_CXSIZEFRAME, dpi) };
1575    let padding_thickness = unsafe { GetSystemMetricsForDpi(SM_CXPADDEDBORDER, dpi) };
1576    resize_frame_thickness + padding_thickness
1577}
1578
1579fn get_frame_thicknessy(dpi: u32) -> i32 {
1580    let resize_frame_thickness = unsafe { GetSystemMetricsForDpi(SM_CYSIZEFRAME, dpi) };
1581    let padding_thickness = unsafe { GetSystemMetricsForDpi(SM_CXPADDEDBORDER, dpi) };
1582    resize_frame_thickness + padding_thickness
1583}
1584
1585fn notify_frame_changed(handle: HWND) {
1586    unsafe {
1587        SetWindowPos(
1588            handle,
1589            None,
1590            0,
1591            0,
1592            0,
1593            0,
1594            SWP_FRAMECHANGED
1595                | SWP_NOACTIVATE
1596                | SWP_NOCOPYBITS
1597                | SWP_NOMOVE
1598                | SWP_NOOWNERZORDER
1599                | SWP_NOREPOSITION
1600                | SWP_NOSENDCHANGING
1601                | SWP_NOSIZE
1602                | SWP_NOZORDER,
1603        )
1604        .log_err();
1605    }
1606}