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::*;
  21
  22pub(crate) const WM_GPUI_CURSOR_STYLE_CHANGED: u32 = WM_USER + 1;
  23pub(crate) const WM_GPUI_CLOSE_ONE_WINDOW: u32 = WM_USER + 2;
  24pub(crate) const WM_GPUI_TASK_DISPATCHED_ON_MAIN_THREAD: u32 = WM_USER + 3;
  25pub(crate) const WM_GPUI_DOCK_MENU_ACTION: u32 = WM_USER + 4;
  26
  27const SIZE_MOVE_LOOP_TIMER_ID: usize = 1;
  28const AUTO_HIDE_TASKBAR_THICKNESS_PX: i32 = 1;
  29
  30pub(crate) fn handle_msg(
  31    handle: HWND,
  32    msg: u32,
  33    wparam: WPARAM,
  34    lparam: LPARAM,
  35    state_ptr: Rc<WindowsWindowStatePtr>,
  36) -> LRESULT {
  37    let handled = match msg {
  38        WM_ACTIVATE => handle_activate_msg(handle, wparam, state_ptr),
  39        WM_CREATE => handle_create_msg(handle, state_ptr),
  40        WM_MOVE => handle_move_msg(handle, lparam, state_ptr),
  41        WM_SIZE => handle_size_msg(wparam, lparam, state_ptr),
  42        WM_GETMINMAXINFO => handle_get_min_max_info_msg(lparam, state_ptr),
  43        WM_ENTERSIZEMOVE | WM_ENTERMENULOOP => handle_size_move_loop(handle),
  44        WM_EXITSIZEMOVE | WM_EXITMENULOOP => handle_size_move_loop_exit(handle),
  45        WM_TIMER => handle_timer_msg(handle, wparam, state_ptr),
  46        WM_NCCALCSIZE => handle_calc_client_size(handle, wparam, lparam, state_ptr),
  47        WM_DPICHANGED => handle_dpi_changed_msg(handle, wparam, lparam, state_ptr),
  48        WM_DISPLAYCHANGE => handle_display_change_msg(handle, state_ptr),
  49        WM_NCHITTEST => handle_hit_test_msg(handle, msg, wparam, lparam, state_ptr),
  50        WM_PAINT => handle_paint_msg(handle, state_ptr),
  51        WM_CLOSE => handle_close_msg(state_ptr),
  52        WM_DESTROY => handle_destroy_msg(handle, state_ptr),
  53        WM_MOUSEMOVE => handle_mouse_move_msg(handle, lparam, wparam, state_ptr),
  54        WM_MOUSELEAVE | WM_NCMOUSELEAVE => handle_mouse_leave_msg(state_ptr),
  55        WM_NCMOUSEMOVE => handle_nc_mouse_move_msg(handle, lparam, state_ptr),
  56        WM_NCLBUTTONDOWN => {
  57            handle_nc_mouse_down_msg(handle, MouseButton::Left, wparam, lparam, state_ptr)
  58        }
  59        WM_NCRBUTTONDOWN => {
  60            handle_nc_mouse_down_msg(handle, MouseButton::Right, wparam, lparam, state_ptr)
  61        }
  62        WM_NCMBUTTONDOWN => {
  63            handle_nc_mouse_down_msg(handle, MouseButton::Middle, wparam, lparam, state_ptr)
  64        }
  65        WM_NCLBUTTONUP => {
  66            handle_nc_mouse_up_msg(handle, MouseButton::Left, wparam, lparam, state_ptr)
  67        }
  68        WM_NCRBUTTONUP => {
  69            handle_nc_mouse_up_msg(handle, MouseButton::Right, wparam, lparam, state_ptr)
  70        }
  71        WM_NCMBUTTONUP => {
  72            handle_nc_mouse_up_msg(handle, MouseButton::Middle, wparam, lparam, state_ptr)
  73        }
  74        WM_LBUTTONDOWN => handle_mouse_down_msg(handle, MouseButton::Left, lparam, state_ptr),
  75        WM_RBUTTONDOWN => handle_mouse_down_msg(handle, MouseButton::Right, lparam, state_ptr),
  76        WM_MBUTTONDOWN => handle_mouse_down_msg(handle, MouseButton::Middle, lparam, state_ptr),
  77        WM_XBUTTONDOWN => {
  78            handle_xbutton_msg(handle, wparam, lparam, handle_mouse_down_msg, state_ptr)
  79        }
  80        WM_LBUTTONUP => handle_mouse_up_msg(handle, MouseButton::Left, lparam, state_ptr),
  81        WM_RBUTTONUP => handle_mouse_up_msg(handle, MouseButton::Right, lparam, state_ptr),
  82        WM_MBUTTONUP => handle_mouse_up_msg(handle, MouseButton::Middle, lparam, state_ptr),
  83        WM_XBUTTONUP => handle_xbutton_msg(handle, wparam, lparam, handle_mouse_up_msg, state_ptr),
  84        WM_MOUSEWHEEL => handle_mouse_wheel_msg(handle, wparam, lparam, state_ptr),
  85        WM_MOUSEHWHEEL => handle_mouse_horizontal_wheel_msg(handle, wparam, lparam, state_ptr),
  86        WM_SYSKEYDOWN => handle_syskeydown_msg(wparam, lparam, state_ptr),
  87        WM_SYSKEYUP => handle_syskeyup_msg(wparam, state_ptr),
  88        WM_SYSCOMMAND => handle_system_command(wparam, state_ptr),
  89        WM_KEYDOWN => handle_keydown_msg(wparam, lparam, state_ptr),
  90        WM_KEYUP => handle_keyup_msg(wparam, state_ptr),
  91        WM_CHAR => handle_char_msg(wparam, lparam, state_ptr),
  92        WM_DEADCHAR => handle_dead_char_msg(wparam, state_ptr),
  93        WM_IME_STARTCOMPOSITION => handle_ime_position(handle, state_ptr),
  94        WM_IME_COMPOSITION => handle_ime_composition(handle, lparam, state_ptr),
  95        WM_SETCURSOR => handle_set_cursor(lparam, state_ptr),
  96        WM_SETTINGCHANGE => handle_system_settings_changed(handle, lparam, state_ptr),
  97        WM_INPUTLANGCHANGE => handle_input_language_changed(lparam, state_ptr),
  98        WM_GPUI_CURSOR_STYLE_CHANGED => handle_cursor_changed(lparam, state_ptr),
  99        _ => None,
 100    };
 101    if let Some(n) = handled {
 102        LRESULT(n)
 103    } else {
 104        unsafe { DefWindowProcW(handle, msg, wparam, lparam) }
 105    }
 106}
 107
 108fn handle_move_msg(
 109    handle: HWND,
 110    lparam: LPARAM,
 111    state_ptr: Rc<WindowsWindowStatePtr>,
 112) -> Option<isize> {
 113    let mut lock = state_ptr.state.borrow_mut();
 114    let origin = logical_point(
 115        lparam.signed_loword() as f32,
 116        lparam.signed_hiword() as f32,
 117        lock.scale_factor,
 118    );
 119    lock.origin = origin;
 120    let size = lock.logical_size;
 121    let center_x = origin.x.0 + size.width.0 / 2.;
 122    let center_y = origin.y.0 + size.height.0 / 2.;
 123    let monitor_bounds = lock.display.bounds();
 124    if center_x < monitor_bounds.left().0
 125        || center_x > monitor_bounds.right().0
 126        || center_y < monitor_bounds.top().0
 127        || center_y > monitor_bounds.bottom().0
 128    {
 129        // center of the window may have moved to another monitor
 130        let monitor = unsafe { MonitorFromWindow(handle, MONITOR_DEFAULTTONULL) };
 131        // minimize the window can trigger this event too, in this case,
 132        // monitor is invalid, we do nothing.
 133        if !monitor.is_invalid() && lock.display.handle != monitor {
 134            // we will get the same monitor if we only have one
 135            lock.display = WindowsDisplay::new_with_handle(monitor);
 136        }
 137    }
 138    if let Some(mut callback) = lock.callbacks.moved.take() {
 139        drop(lock);
 140        callback();
 141        state_ptr.state.borrow_mut().callbacks.moved = Some(callback);
 142    }
 143    Some(0)
 144}
 145
 146fn handle_get_min_max_info_msg(
 147    lparam: LPARAM,
 148    state_ptr: Rc<WindowsWindowStatePtr>,
 149) -> Option<isize> {
 150    let lock = state_ptr.state.borrow();
 151    if let Some(min_size) = lock.min_size {
 152        let scale_factor = lock.scale_factor;
 153        let boarder_offset = lock.border_offset;
 154        drop(lock);
 155
 156        unsafe {
 157            let minmax_info = &mut *(lparam.0 as *mut MINMAXINFO);
 158            minmax_info.ptMinTrackSize.x =
 159                min_size.width.scale(scale_factor).0 as i32 + boarder_offset.width_offset;
 160            minmax_info.ptMinTrackSize.y =
 161                min_size.height.scale(scale_factor).0 as i32 + boarder_offset.height_offset;
 162        }
 163        Some(0)
 164    } else {
 165        None
 166    }
 167}
 168
 169fn handle_size_msg(
 170    wparam: WPARAM,
 171    lparam: LPARAM,
 172    state_ptr: Rc<WindowsWindowStatePtr>,
 173) -> Option<isize> {
 174    let mut lock = state_ptr.state.borrow_mut();
 175
 176    // Don't resize the renderer when the window is minimized, but record that it was minimized so
 177    // that on restore the swap chain can be recreated via `update_drawable_size_even_if_unchanged`.
 178    if wparam.0 == SIZE_MINIMIZED as usize {
 179        lock.restore_from_minimized = lock.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    let scale_factor = lock.scale_factor;
 187    if lock.restore_from_minimized.is_some() {
 188        lock.renderer
 189            .update_drawable_size_even_if_unchanged(new_size);
 190        lock.callbacks.request_frame = lock.restore_from_minimized.take();
 191    } else {
 192        lock.renderer.update_drawable_size(new_size);
 193    }
 194    let new_size = new_size.to_pixels(scale_factor);
 195    lock.logical_size = new_size;
 196    if let Some(mut callback) = lock.callbacks.resize.take() {
 197        drop(lock);
 198        callback(new_size, scale_factor);
 199        state_ptr.state.borrow_mut().callbacks.resize = Some(callback);
 200    }
 201    Some(0)
 202}
 203
 204fn handle_size_move_loop(handle: HWND) -> Option<isize> {
 205    unsafe {
 206        let ret = SetTimer(
 207            Some(handle),
 208            SIZE_MOVE_LOOP_TIMER_ID,
 209            USER_TIMER_MINIMUM,
 210            None,
 211        );
 212        if ret == 0 {
 213            log::error!(
 214                "unable to create timer: {}",
 215                std::io::Error::last_os_error()
 216            );
 217        }
 218    }
 219    None
 220}
 221
 222fn handle_size_move_loop_exit(handle: HWND) -> Option<isize> {
 223    unsafe {
 224        KillTimer(Some(handle), SIZE_MOVE_LOOP_TIMER_ID).log_err();
 225    }
 226    None
 227}
 228
 229fn handle_timer_msg(
 230    handle: HWND,
 231    wparam: WPARAM,
 232    state_ptr: Rc<WindowsWindowStatePtr>,
 233) -> Option<isize> {
 234    if wparam.0 == SIZE_MOVE_LOOP_TIMER_ID {
 235        for runnable in state_ptr.main_receiver.drain() {
 236            runnable.run();
 237        }
 238        handle_paint_msg(handle, state_ptr)
 239    } else {
 240        None
 241    }
 242}
 243
 244fn handle_paint_msg(handle: HWND, state_ptr: Rc<WindowsWindowStatePtr>) -> Option<isize> {
 245    let mut lock = state_ptr.state.borrow_mut();
 246    if let Some(mut request_frame) = lock.callbacks.request_frame.take() {
 247        drop(lock);
 248        request_frame(Default::default());
 249        state_ptr.state.borrow_mut().callbacks.request_frame = Some(request_frame);
 250    }
 251    unsafe { ValidateRect(Some(handle), None).ok().log_err() };
 252    Some(0)
 253}
 254
 255fn handle_close_msg(state_ptr: Rc<WindowsWindowStatePtr>) -> Option<isize> {
 256    let mut lock = state_ptr.state.borrow_mut();
 257    if let Some(mut callback) = lock.callbacks.should_close.take() {
 258        drop(lock);
 259        let should_close = callback();
 260        state_ptr.state.borrow_mut().callbacks.should_close = Some(callback);
 261        if should_close { None } else { Some(0) }
 262    } else {
 263        None
 264    }
 265}
 266
 267fn handle_destroy_msg(handle: HWND, state_ptr: Rc<WindowsWindowStatePtr>) -> Option<isize> {
 268    let callback = {
 269        let mut lock = state_ptr.state.borrow_mut();
 270        lock.callbacks.close.take()
 271    };
 272    if let Some(callback) = callback {
 273        callback();
 274    }
 275    unsafe {
 276        PostThreadMessageW(
 277            state_ptr.main_thread_id_win32,
 278            WM_GPUI_CLOSE_ONE_WINDOW,
 279            WPARAM(state_ptr.validation_number),
 280            LPARAM(handle.0 as isize),
 281        )
 282        .log_err();
 283    }
 284    Some(0)
 285}
 286
 287fn handle_mouse_move_msg(
 288    handle: HWND,
 289    lparam: LPARAM,
 290    wparam: WPARAM,
 291    state_ptr: Rc<WindowsWindowStatePtr>,
 292) -> Option<isize> {
 293    start_tracking_mouse(handle, &state_ptr, TME_LEAVE);
 294
 295    let mut lock = state_ptr.state.borrow_mut();
 296    if let Some(mut callback) = lock.callbacks.input.take() {
 297        let scale_factor = lock.scale_factor;
 298        drop(lock);
 299        let pressed_button = match MODIFIERKEYS_FLAGS(wparam.loword() as u32) {
 300            flags if flags.contains(MK_LBUTTON) => Some(MouseButton::Left),
 301            flags if flags.contains(MK_RBUTTON) => Some(MouseButton::Right),
 302            flags if flags.contains(MK_MBUTTON) => Some(MouseButton::Middle),
 303            flags if flags.contains(MK_XBUTTON1) => {
 304                Some(MouseButton::Navigate(NavigationDirection::Back))
 305            }
 306            flags if flags.contains(MK_XBUTTON2) => {
 307                Some(MouseButton::Navigate(NavigationDirection::Forward))
 308            }
 309            _ => None,
 310        };
 311        let x = lparam.signed_loword() as f32;
 312        let y = lparam.signed_hiword() as f32;
 313        let event = MouseMoveEvent {
 314            position: logical_point(x, y, scale_factor),
 315            pressed_button,
 316            modifiers: current_modifiers(),
 317        };
 318        let result = if callback(PlatformInput::MouseMove(event)).default_prevented {
 319            Some(0)
 320        } else {
 321            Some(1)
 322        };
 323        state_ptr.state.borrow_mut().callbacks.input = Some(callback);
 324        return result;
 325    }
 326    Some(1)
 327}
 328
 329fn handle_mouse_leave_msg(state_ptr: Rc<WindowsWindowStatePtr>) -> Option<isize> {
 330    let mut lock = state_ptr.state.borrow_mut();
 331    lock.hovered = false;
 332    if let Some(mut callback) = lock.callbacks.hovered_status_change.take() {
 333        drop(lock);
 334        callback(false);
 335        state_ptr.state.borrow_mut().callbacks.hovered_status_change = Some(callback);
 336    }
 337
 338    Some(0)
 339}
 340
 341fn handle_syskeydown_msg(
 342    wparam: WPARAM,
 343    lparam: LPARAM,
 344    state_ptr: Rc<WindowsWindowStatePtr>,
 345) -> Option<isize> {
 346    let mut lock = state_ptr.state.borrow_mut();
 347    let vkey = wparam.loword();
 348    let input = if is_modifier(VIRTUAL_KEY(vkey)) {
 349        let modifiers = current_modifiers();
 350        if let Some(prev_modifiers) = lock.last_reported_modifiers {
 351            if prev_modifiers == modifiers {
 352                return Some(0);
 353            }
 354        }
 355        lock.last_reported_modifiers = Some(modifiers);
 356        PlatformInput::ModifiersChanged(ModifiersChangedEvent { modifiers })
 357    } else {
 358        let keystroke = parse_syskeydown_msg_keystroke(wparam)?;
 359        PlatformInput::KeyDown(KeyDownEvent {
 360            keystroke,
 361            is_held: lparam.0 & (0x1 << 30) > 0,
 362        })
 363    };
 364    let mut func = lock.callbacks.input.take()?;
 365    drop(lock);
 366    let result = if !func(input).propagate {
 367        state_ptr.state.borrow_mut().system_key_handled = true;
 368        Some(0)
 369    } else {
 370        // we need to call `DefWindowProcW`, or we will lose the system-wide `Alt+F4`, `Alt+{other keys}`
 371        // shortcuts.
 372        None
 373    };
 374    state_ptr.state.borrow_mut().callbacks.input = Some(func);
 375
 376    result
 377}
 378
 379fn handle_syskeyup_msg(wparam: WPARAM, state_ptr: Rc<WindowsWindowStatePtr>) -> Option<isize> {
 380    let mut lock = state_ptr.state.borrow_mut();
 381    let vkey = wparam.loword();
 382    let input = if is_modifier(VIRTUAL_KEY(vkey)) {
 383        let modifiers = current_modifiers();
 384        if let Some(prev_modifiers) = lock.last_reported_modifiers {
 385            if prev_modifiers == modifiers {
 386                return Some(0);
 387            }
 388        }
 389        lock.last_reported_modifiers = Some(modifiers);
 390        PlatformInput::ModifiersChanged(ModifiersChangedEvent { modifiers })
 391    } else {
 392        let keystroke = parse_syskeydown_msg_keystroke(wparam)?;
 393        PlatformInput::KeyUp(KeyUpEvent { keystroke })
 394    };
 395    let mut func = lock.callbacks.input.take()?;
 396    drop(lock);
 397    let result = if !func(input).propagate {
 398        Some(0)
 399    } else {
 400        // we need to call `DefWindowProcW`, or we will lose the system-wide `Alt+F4`, `Alt+{other keys}`
 401        // shortcuts.
 402        None
 403    };
 404    state_ptr.state.borrow_mut().callbacks.input = Some(func);
 405
 406    result
 407}
 408
 409fn handle_keydown_msg(
 410    wparam: WPARAM,
 411    lparam: LPARAM,
 412    state_ptr: Rc<WindowsWindowStatePtr>,
 413) -> Option<isize> {
 414    let Some(keystroke_or_modifier) = parse_keystroke_from_vkey(wparam, false) else {
 415        return Some(1);
 416    };
 417    let mut lock = state_ptr.state.borrow_mut();
 418
 419    let event = match keystroke_or_modifier {
 420        KeystrokeOrModifier::Keystroke(keystroke) => PlatformInput::KeyDown(KeyDownEvent {
 421            keystroke,
 422            is_held: lparam.0 & (0x1 << 30) > 0,
 423        }),
 424        KeystrokeOrModifier::Modifier(modifiers) => {
 425            if let Some(prev_modifiers) = lock.last_reported_modifiers {
 426                if prev_modifiers == modifiers {
 427                    return Some(0);
 428                }
 429            }
 430            lock.last_reported_modifiers = Some(modifiers);
 431            PlatformInput::ModifiersChanged(ModifiersChangedEvent { modifiers })
 432        }
 433    };
 434    let Some(mut func) = lock.callbacks.input.take() else {
 435        return Some(1);
 436    };
 437    drop(lock);
 438
 439    let result = if func(event).default_prevented {
 440        Some(0)
 441    } else {
 442        Some(1)
 443    };
 444    state_ptr.state.borrow_mut().callbacks.input = Some(func);
 445
 446    result
 447}
 448
 449fn handle_keyup_msg(wparam: WPARAM, state_ptr: Rc<WindowsWindowStatePtr>) -> Option<isize> {
 450    let Some(keystroke_or_modifier) = parse_keystroke_from_vkey(wparam, true) else {
 451        return Some(1);
 452    };
 453    let mut lock = state_ptr.state.borrow_mut();
 454
 455    let event = match keystroke_or_modifier {
 456        KeystrokeOrModifier::Keystroke(keystroke) => PlatformInput::KeyUp(KeyUpEvent { keystroke }),
 457        KeystrokeOrModifier::Modifier(modifiers) => {
 458            if let Some(prev_modifiers) = lock.last_reported_modifiers {
 459                if prev_modifiers == modifiers {
 460                    return Some(0);
 461                }
 462            }
 463            lock.last_reported_modifiers = Some(modifiers);
 464            PlatformInput::ModifiersChanged(ModifiersChangedEvent { modifiers })
 465        }
 466    };
 467    let Some(mut func) = lock.callbacks.input.take() else {
 468        return Some(1);
 469    };
 470    drop(lock);
 471
 472    let result = if func(event).default_prevented {
 473        Some(0)
 474    } else {
 475        Some(1)
 476    };
 477    state_ptr.state.borrow_mut().callbacks.input = Some(func);
 478
 479    result
 480}
 481
 482fn handle_char_msg(
 483    wparam: WPARAM,
 484    lparam: LPARAM,
 485    state_ptr: Rc<WindowsWindowStatePtr>,
 486) -> Option<isize> {
 487    let Some(keystroke) = parse_char_msg_keystroke(wparam) else {
 488        return Some(1);
 489    };
 490    let mut lock = state_ptr.state.borrow_mut();
 491    let Some(mut func) = lock.callbacks.input.take() else {
 492        return Some(1);
 493    };
 494    drop(lock);
 495    let key_char = keystroke.key_char.clone();
 496    let event = KeyDownEvent {
 497        keystroke,
 498        is_held: lparam.0 & (0x1 << 30) > 0,
 499    };
 500    let dispatch_event_result = func(PlatformInput::KeyDown(event));
 501    state_ptr.state.borrow_mut().callbacks.input = Some(func);
 502
 503    if dispatch_event_result.default_prevented || !dispatch_event_result.propagate {
 504        return Some(0);
 505    }
 506    let Some(ime_char) = key_char else {
 507        return Some(1);
 508    };
 509    with_input_handler(&state_ptr, |input_handler| {
 510        input_handler.replace_text_in_range(None, &ime_char);
 511    });
 512
 513    Some(0)
 514}
 515
 516fn handle_dead_char_msg(wparam: WPARAM, state_ptr: Rc<WindowsWindowStatePtr>) -> Option<isize> {
 517    let ch = char::from_u32(wparam.0 as u32)?.to_string();
 518    with_input_handler(&state_ptr, |input_handler| {
 519        input_handler.replace_and_mark_text_in_range(None, &ch, None);
 520    });
 521    None
 522}
 523
 524fn handle_mouse_down_msg(
 525    handle: HWND,
 526    button: MouseButton,
 527    lparam: LPARAM,
 528    state_ptr: Rc<WindowsWindowStatePtr>,
 529) -> Option<isize> {
 530    unsafe { SetCapture(handle) };
 531    let mut lock = state_ptr.state.borrow_mut();
 532    if let Some(mut callback) = lock.callbacks.input.take() {
 533        let x = lparam.signed_loword() as f32;
 534        let y = lparam.signed_hiword() as f32;
 535        let physical_point = point(DevicePixels(x as i32), DevicePixels(y as i32));
 536        let click_count = lock.click_state.update(button, physical_point);
 537        let scale_factor = lock.scale_factor;
 538        drop(lock);
 539
 540        let event = MouseDownEvent {
 541            button,
 542            position: logical_point(x, y, scale_factor),
 543            modifiers: current_modifiers(),
 544            click_count,
 545            first_mouse: false,
 546        };
 547        let result = if callback(PlatformInput::MouseDown(event)).default_prevented {
 548            Some(0)
 549        } else {
 550            Some(1)
 551        };
 552        state_ptr.state.borrow_mut().callbacks.input = Some(callback);
 553
 554        result
 555    } else {
 556        Some(1)
 557    }
 558}
 559
 560fn handle_mouse_up_msg(
 561    _handle: HWND,
 562    button: MouseButton,
 563    lparam: LPARAM,
 564    state_ptr: Rc<WindowsWindowStatePtr>,
 565) -> Option<isize> {
 566    unsafe { ReleaseCapture().log_err() };
 567    let mut lock = state_ptr.state.borrow_mut();
 568    if let Some(mut callback) = lock.callbacks.input.take() {
 569        let x = lparam.signed_loword() as f32;
 570        let y = lparam.signed_hiword() as f32;
 571        let click_count = lock.click_state.current_count;
 572        let scale_factor = lock.scale_factor;
 573        drop(lock);
 574
 575        let event = MouseUpEvent {
 576            button,
 577            position: logical_point(x, y, scale_factor),
 578            modifiers: current_modifiers(),
 579            click_count,
 580        };
 581        let result = if callback(PlatformInput::MouseUp(event)).default_prevented {
 582            Some(0)
 583        } else {
 584            Some(1)
 585        };
 586        state_ptr.state.borrow_mut().callbacks.input = Some(callback);
 587
 588        result
 589    } else {
 590        Some(1)
 591    }
 592}
 593
 594fn handle_xbutton_msg(
 595    handle: HWND,
 596    wparam: WPARAM,
 597    lparam: LPARAM,
 598    handler: impl Fn(HWND, MouseButton, LPARAM, Rc<WindowsWindowStatePtr>) -> Option<isize>,
 599    state_ptr: Rc<WindowsWindowStatePtr>,
 600) -> Option<isize> {
 601    let nav_dir = match wparam.hiword() {
 602        XBUTTON1 => NavigationDirection::Back,
 603        XBUTTON2 => NavigationDirection::Forward,
 604        _ => return Some(1),
 605    };
 606    handler(handle, MouseButton::Navigate(nav_dir), lparam, state_ptr)
 607}
 608
 609fn handle_mouse_wheel_msg(
 610    handle: HWND,
 611    wparam: WPARAM,
 612    lparam: LPARAM,
 613    state_ptr: Rc<WindowsWindowStatePtr>,
 614) -> Option<isize> {
 615    let modifiers = current_modifiers();
 616    let mut lock = state_ptr.state.borrow_mut();
 617    if let Some(mut callback) = lock.callbacks.input.take() {
 618        let scale_factor = lock.scale_factor;
 619        let wheel_scroll_amount = match modifiers.shift {
 620            true => lock.system_settings.mouse_wheel_settings.wheel_scroll_chars,
 621            false => lock.system_settings.mouse_wheel_settings.wheel_scroll_lines,
 622        };
 623        drop(lock);
 624        let wheel_distance =
 625            (wparam.signed_hiword() as f32 / WHEEL_DELTA as f32) * wheel_scroll_amount as f32;
 626        let mut cursor_point = POINT {
 627            x: lparam.signed_loword().into(),
 628            y: lparam.signed_hiword().into(),
 629        };
 630        unsafe { ScreenToClient(handle, &mut cursor_point).ok().log_err() };
 631        let event = ScrollWheelEvent {
 632            position: logical_point(cursor_point.x as f32, cursor_point.y as f32, scale_factor),
 633            delta: ScrollDelta::Lines(match modifiers.shift {
 634                true => Point {
 635                    x: wheel_distance,
 636                    y: 0.0,
 637                },
 638                false => Point {
 639                    y: wheel_distance,
 640                    x: 0.0,
 641                },
 642            }),
 643            modifiers: current_modifiers(),
 644            touch_phase: TouchPhase::Moved,
 645        };
 646        let result = if callback(PlatformInput::ScrollWheel(event)).default_prevented {
 647            Some(0)
 648        } else {
 649            Some(1)
 650        };
 651        state_ptr.state.borrow_mut().callbacks.input = Some(callback);
 652
 653        result
 654    } else {
 655        Some(1)
 656    }
 657}
 658
 659fn handle_mouse_horizontal_wheel_msg(
 660    handle: HWND,
 661    wparam: WPARAM,
 662    lparam: LPARAM,
 663    state_ptr: Rc<WindowsWindowStatePtr>,
 664) -> Option<isize> {
 665    let mut lock = state_ptr.state.borrow_mut();
 666    if let Some(mut callback) = lock.callbacks.input.take() {
 667        let scale_factor = lock.scale_factor;
 668        let wheel_scroll_chars = lock.system_settings.mouse_wheel_settings.wheel_scroll_chars;
 669        drop(lock);
 670        let wheel_distance =
 671            (-wparam.signed_hiword() as f32 / WHEEL_DELTA as f32) * wheel_scroll_chars as f32;
 672        let mut cursor_point = POINT {
 673            x: lparam.signed_loword().into(),
 674            y: lparam.signed_hiword().into(),
 675        };
 676        unsafe { ScreenToClient(handle, &mut cursor_point).ok().log_err() };
 677        let event = ScrollWheelEvent {
 678            position: logical_point(cursor_point.x as f32, cursor_point.y as f32, scale_factor),
 679            delta: ScrollDelta::Lines(Point {
 680                x: wheel_distance,
 681                y: 0.0,
 682            }),
 683            modifiers: current_modifiers(),
 684            touch_phase: TouchPhase::Moved,
 685        };
 686        let result = if callback(PlatformInput::ScrollWheel(event)).default_prevented {
 687            Some(0)
 688        } else {
 689            Some(1)
 690        };
 691        state_ptr.state.borrow_mut().callbacks.input = Some(callback);
 692
 693        result
 694    } else {
 695        Some(1)
 696    }
 697}
 698
 699fn retrieve_caret_position(state_ptr: &Rc<WindowsWindowStatePtr>) -> Option<POINT> {
 700    with_input_handler_and_scale_factor(state_ptr, |input_handler, scale_factor| {
 701        let caret_range = input_handler.selected_text_range(false)?;
 702        let caret_position = input_handler.bounds_for_range(caret_range.range)?;
 703        Some(POINT {
 704            // logical to physical
 705            x: (caret_position.origin.x.0 * scale_factor) as i32,
 706            y: (caret_position.origin.y.0 * scale_factor) as i32
 707                + ((caret_position.size.height.0 * scale_factor) as i32 / 2),
 708        })
 709    })
 710}
 711
 712fn handle_ime_position(handle: HWND, state_ptr: Rc<WindowsWindowStatePtr>) -> Option<isize> {
 713    unsafe {
 714        let ctx = ImmGetContext(handle);
 715
 716        let Some(caret_position) = retrieve_caret_position(&state_ptr) else {
 717            return Some(0);
 718        };
 719        {
 720            let config = COMPOSITIONFORM {
 721                dwStyle: CFS_POINT,
 722                ptCurrentPos: caret_position,
 723                ..Default::default()
 724            };
 725            ImmSetCompositionWindow(ctx, &config as _).ok().log_err();
 726        }
 727        {
 728            let config = CANDIDATEFORM {
 729                dwStyle: CFS_CANDIDATEPOS,
 730                ptCurrentPos: caret_position,
 731                ..Default::default()
 732            };
 733            ImmSetCandidateWindow(ctx, &config as _).ok().log_err();
 734        }
 735        ImmReleaseContext(handle, ctx).ok().log_err();
 736        Some(0)
 737    }
 738}
 739
 740fn handle_ime_composition(
 741    handle: HWND,
 742    lparam: LPARAM,
 743    state_ptr: Rc<WindowsWindowStatePtr>,
 744) -> Option<isize> {
 745    let ctx = unsafe { ImmGetContext(handle) };
 746    let result = handle_ime_composition_inner(ctx, lparam, state_ptr);
 747    unsafe { ImmReleaseContext(handle, ctx).ok().log_err() };
 748    result
 749}
 750
 751fn handle_ime_composition_inner(
 752    ctx: HIMC,
 753    lparam: LPARAM,
 754    state_ptr: Rc<WindowsWindowStatePtr>,
 755) -> Option<isize> {
 756    let mut ime_input = None;
 757    if lparam.0 as u32 & GCS_COMPSTR.0 > 0 {
 758        let (comp_string, string_len) = parse_ime_compostion_string(ctx)?;
 759        with_input_handler(&state_ptr, |input_handler| {
 760            input_handler.replace_and_mark_text_in_range(
 761                None,
 762                &comp_string,
 763                Some(string_len..string_len),
 764            );
 765        })?;
 766        ime_input = Some(comp_string);
 767    }
 768    if lparam.0 as u32 & GCS_CURSORPOS.0 > 0 {
 769        let comp_string = &ime_input?;
 770        let caret_pos = retrieve_composition_cursor_position(ctx);
 771        with_input_handler(&state_ptr, |input_handler| {
 772            input_handler.replace_and_mark_text_in_range(
 773                None,
 774                comp_string,
 775                Some(caret_pos..caret_pos),
 776            );
 777        })?;
 778    }
 779    if lparam.0 as u32 & GCS_RESULTSTR.0 > 0 {
 780        let comp_result = parse_ime_compostion_result(ctx)?;
 781        with_input_handler(&state_ptr, |input_handler| {
 782            input_handler.replace_text_in_range(None, &comp_result);
 783        })?;
 784        return Some(0);
 785    }
 786    // currently, we don't care other stuff
 787    None
 788}
 789
 790/// SEE: https://learn.microsoft.com/en-us/windows/win32/winmsg/wm-nccalcsize
 791fn handle_calc_client_size(
 792    handle: HWND,
 793    wparam: WPARAM,
 794    lparam: LPARAM,
 795    state_ptr: Rc<WindowsWindowStatePtr>,
 796) -> Option<isize> {
 797    if !state_ptr.hide_title_bar || state_ptr.state.borrow().is_fullscreen() || wparam.0 == 0 {
 798        return None;
 799    }
 800
 801    let is_maximized = state_ptr.state.borrow().is_maximized();
 802    let insets = get_client_area_insets(handle, is_maximized, state_ptr.windows_version);
 803    // wparam is TRUE so lparam points to an NCCALCSIZE_PARAMS structure
 804    let mut params = lparam.0 as *mut NCCALCSIZE_PARAMS;
 805    let mut requested_client_rect = unsafe { &mut ((*params).rgrc) };
 806
 807    requested_client_rect[0].left += insets.left;
 808    requested_client_rect[0].top += insets.top;
 809    requested_client_rect[0].right -= insets.right;
 810    requested_client_rect[0].bottom -= insets.bottom;
 811
 812    // Fix auto hide taskbar not showing. This solution is based on the approach
 813    // used by Chrome. However, it may result in one row of pixels being obscured
 814    // in our client area. But as Chrome says, "there seems to be no better solution."
 815    if is_maximized {
 816        if let Some(ref taskbar_position) = state_ptr
 817            .state
 818            .borrow()
 819            .system_settings
 820            .auto_hide_taskbar_position
 821        {
 822            // Fot the auto-hide taskbar, adjust in by 1 pixel on taskbar edge,
 823            // so the window isn't treated as a "fullscreen app", which would cause
 824            // the taskbar to disappear.
 825            match taskbar_position {
 826                AutoHideTaskbarPosition::Left => {
 827                    requested_client_rect[0].left += AUTO_HIDE_TASKBAR_THICKNESS_PX
 828                }
 829                AutoHideTaskbarPosition::Top => {
 830                    requested_client_rect[0].top += AUTO_HIDE_TASKBAR_THICKNESS_PX
 831                }
 832                AutoHideTaskbarPosition::Right => {
 833                    requested_client_rect[0].right -= AUTO_HIDE_TASKBAR_THICKNESS_PX
 834                }
 835                AutoHideTaskbarPosition::Bottom => {
 836                    requested_client_rect[0].bottom -= AUTO_HIDE_TASKBAR_THICKNESS_PX
 837                }
 838            }
 839        }
 840    }
 841
 842    Some(0)
 843}
 844
 845fn handle_activate_msg(
 846    handle: HWND,
 847    wparam: WPARAM,
 848    state_ptr: Rc<WindowsWindowStatePtr>,
 849) -> Option<isize> {
 850    let activated = wparam.loword() > 0;
 851    if state_ptr.hide_title_bar {
 852        if let Some(titlebar_rect) = state_ptr.state.borrow().get_titlebar_rect().log_err() {
 853            unsafe {
 854                InvalidateRect(Some(handle), Some(&titlebar_rect), false)
 855                    .ok()
 856                    .log_err()
 857            };
 858        }
 859    }
 860    let this = state_ptr.clone();
 861    state_ptr
 862        .executor
 863        .spawn(async move {
 864            let mut lock = this.state.borrow_mut();
 865            if let Some(mut cb) = lock.callbacks.active_status_change.take() {
 866                drop(lock);
 867                cb(activated);
 868                this.state.borrow_mut().callbacks.active_status_change = Some(cb);
 869            }
 870        })
 871        .detach();
 872
 873    None
 874}
 875
 876fn handle_create_msg(handle: HWND, state_ptr: Rc<WindowsWindowStatePtr>) -> Option<isize> {
 877    if state_ptr.hide_title_bar {
 878        notify_frame_changed(handle);
 879        Some(0)
 880    } else {
 881        None
 882    }
 883}
 884
 885fn handle_dpi_changed_msg(
 886    handle: HWND,
 887    wparam: WPARAM,
 888    lparam: LPARAM,
 889    state_ptr: Rc<WindowsWindowStatePtr>,
 890) -> Option<isize> {
 891    let new_dpi = wparam.loword() as f32;
 892    let mut lock = state_ptr.state.borrow_mut();
 893    lock.scale_factor = new_dpi / USER_DEFAULT_SCREEN_DPI as f32;
 894    lock.border_offset.update(handle).log_err();
 895    drop(lock);
 896
 897    let rect = unsafe { &*(lparam.0 as *const RECT) };
 898    let width = rect.right - rect.left;
 899    let height = rect.bottom - rect.top;
 900    // this will emit `WM_SIZE` and `WM_MOVE` right here
 901    // even before this function returns
 902    // the new size is handled in `WM_SIZE`
 903    unsafe {
 904        SetWindowPos(
 905            handle,
 906            None,
 907            rect.left,
 908            rect.top,
 909            width,
 910            height,
 911            SWP_NOZORDER | SWP_NOACTIVATE,
 912        )
 913        .context("unable to set window position after dpi has changed")
 914        .log_err();
 915    }
 916
 917    Some(0)
 918}
 919
 920/// The following conditions will trigger this event:
 921/// 1. The monitor on which the window is located goes offline or changes resolution.
 922/// 2. Another monitor goes offline, is plugged in, or changes resolution.
 923///
 924/// In either case, the window will only receive information from the monitor on which
 925/// it is located.
 926///
 927/// For example, in the case of condition 2, where the monitor on which the window is
 928/// located has actually changed nothing, it will still receive this event.
 929fn handle_display_change_msg(handle: HWND, state_ptr: Rc<WindowsWindowStatePtr>) -> Option<isize> {
 930    // NOTE:
 931    // Even the `lParam` holds the resolution of the screen, we just ignore it.
 932    // Because WM_DPICHANGED, WM_MOVE, WM_SIZE will come first, window reposition and resize
 933    // are handled there.
 934    // So we only care about if monitor is disconnected.
 935    let previous_monitor = state_ptr.as_ref().state.borrow().display;
 936    if WindowsDisplay::is_connected(previous_monitor.handle) {
 937        // we are fine, other display changed
 938        return None;
 939    }
 940    // display disconnected
 941    // in this case, the OS will move our window to another monitor, and minimize it.
 942    // we deminimize the window and query the monitor after moving
 943    unsafe {
 944        let _ = ShowWindow(handle, SW_SHOWNORMAL);
 945    };
 946    let new_monitor = unsafe { MonitorFromWindow(handle, MONITOR_DEFAULTTONULL) };
 947    // all monitors disconnected
 948    if new_monitor.is_invalid() {
 949        log::error!("No monitor detected!");
 950        return None;
 951    }
 952    let new_display = WindowsDisplay::new_with_handle(new_monitor);
 953    state_ptr.as_ref().state.borrow_mut().display = new_display;
 954    Some(0)
 955}
 956
 957fn handle_hit_test_msg(
 958    handle: HWND,
 959    msg: u32,
 960    wparam: WPARAM,
 961    lparam: LPARAM,
 962    state_ptr: Rc<WindowsWindowStatePtr>,
 963) -> Option<isize> {
 964    if !state_ptr.is_movable {
 965        return None;
 966    }
 967    if !state_ptr.hide_title_bar {
 968        return None;
 969    }
 970
 971    // default handler for resize areas
 972    let hit = unsafe { DefWindowProcW(handle, msg, wparam, lparam) };
 973    if matches!(
 974        hit.0 as u32,
 975        HTNOWHERE
 976            | HTRIGHT
 977            | HTLEFT
 978            | HTTOPLEFT
 979            | HTTOP
 980            | HTTOPRIGHT
 981            | HTBOTTOMRIGHT
 982            | HTBOTTOM
 983            | HTBOTTOMLEFT
 984    ) {
 985        return Some(hit.0);
 986    }
 987
 988    if state_ptr.state.borrow().is_fullscreen() {
 989        return Some(HTCLIENT as _);
 990    }
 991
 992    let dpi = unsafe { GetDpiForWindow(handle) };
 993    let frame_y = unsafe { GetSystemMetricsForDpi(SM_CYFRAME, dpi) };
 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    if !state_ptr.state.borrow().is_maximized() && cursor_point.y >= 0 && cursor_point.y <= frame_y
1001    {
1002        return Some(HTTOP as _);
1003    }
1004
1005    let titlebar_rect = state_ptr.state.borrow().get_titlebar_rect();
1006    if let Ok(titlebar_rect) = titlebar_rect {
1007        if cursor_point.y < titlebar_rect.bottom {
1008            let caption_btn_width = (state_ptr.state.borrow().caption_button_width().0
1009                * state_ptr.state.borrow().scale_factor) as i32;
1010            if cursor_point.x >= titlebar_rect.right - caption_btn_width {
1011                return Some(HTCLOSE as _);
1012            } else if cursor_point.x >= titlebar_rect.right - caption_btn_width * 2 {
1013                return Some(HTMAXBUTTON as _);
1014            } else if cursor_point.x >= titlebar_rect.right - caption_btn_width * 3 {
1015                return Some(HTMINBUTTON as _);
1016            }
1017
1018            return Some(HTCAPTION as _);
1019        }
1020    }
1021
1022    Some(HTCLIENT as _)
1023}
1024
1025fn handle_nc_mouse_move_msg(
1026    handle: HWND,
1027    lparam: LPARAM,
1028    state_ptr: Rc<WindowsWindowStatePtr>,
1029) -> Option<isize> {
1030    if !state_ptr.hide_title_bar {
1031        return None;
1032    }
1033
1034    start_tracking_mouse(handle, &state_ptr, TME_LEAVE | TME_NONCLIENT);
1035
1036    let mut lock = state_ptr.state.borrow_mut();
1037    if let Some(mut callback) = lock.callbacks.input.take() {
1038        let scale_factor = lock.scale_factor;
1039        drop(lock);
1040        let mut cursor_point = POINT {
1041            x: lparam.signed_loword().into(),
1042            y: lparam.signed_hiword().into(),
1043        };
1044        unsafe { ScreenToClient(handle, &mut cursor_point).ok().log_err() };
1045        let event = MouseMoveEvent {
1046            position: logical_point(cursor_point.x as f32, cursor_point.y as f32, scale_factor),
1047            pressed_button: None,
1048            modifiers: current_modifiers(),
1049        };
1050        let result = if callback(PlatformInput::MouseMove(event)).default_prevented {
1051            Some(0)
1052        } else {
1053            Some(1)
1054        };
1055        state_ptr.state.borrow_mut().callbacks.input = Some(callback);
1056
1057        result
1058    } else {
1059        None
1060    }
1061}
1062
1063fn handle_nc_mouse_down_msg(
1064    handle: HWND,
1065    button: MouseButton,
1066    wparam: WPARAM,
1067    lparam: LPARAM,
1068    state_ptr: Rc<WindowsWindowStatePtr>,
1069) -> Option<isize> {
1070    if !state_ptr.hide_title_bar {
1071        return None;
1072    }
1073
1074    let mut lock = state_ptr.state.borrow_mut();
1075    if let Some(mut callback) = lock.callbacks.input.take() {
1076        let scale_factor = lock.scale_factor;
1077        let mut cursor_point = POINT {
1078            x: lparam.signed_loword().into(),
1079            y: lparam.signed_hiword().into(),
1080        };
1081        unsafe { ScreenToClient(handle, &mut cursor_point).ok().log_err() };
1082        let physical_point = point(DevicePixels(cursor_point.x), DevicePixels(cursor_point.y));
1083        let click_count = lock.click_state.update(button, physical_point);
1084        drop(lock);
1085        let event = MouseDownEvent {
1086            button,
1087            position: logical_point(cursor_point.x as f32, cursor_point.y as f32, scale_factor),
1088            modifiers: current_modifiers(),
1089            click_count,
1090            first_mouse: false,
1091        };
1092        let result = if callback(PlatformInput::MouseDown(event)).default_prevented {
1093            Some(0)
1094        } else {
1095            None
1096        };
1097        state_ptr.state.borrow_mut().callbacks.input = Some(callback);
1098
1099        if result.is_some() {
1100            return result;
1101        }
1102    } else {
1103        drop(lock);
1104    };
1105
1106    // Since these are handled in handle_nc_mouse_up_msg we must prevent the default window proc
1107    if button == MouseButton::Left {
1108        match wparam.0 as u32 {
1109            HTMINBUTTON => state_ptr.state.borrow_mut().nc_button_pressed = Some(HTMINBUTTON),
1110            HTMAXBUTTON => state_ptr.state.borrow_mut().nc_button_pressed = Some(HTMAXBUTTON),
1111            HTCLOSE => state_ptr.state.borrow_mut().nc_button_pressed = Some(HTCLOSE),
1112            _ => return None,
1113        };
1114        Some(0)
1115    } else {
1116        None
1117    }
1118}
1119
1120fn handle_nc_mouse_up_msg(
1121    handle: HWND,
1122    button: MouseButton,
1123    wparam: WPARAM,
1124    lparam: LPARAM,
1125    state_ptr: Rc<WindowsWindowStatePtr>,
1126) -> Option<isize> {
1127    if !state_ptr.hide_title_bar {
1128        return None;
1129    }
1130
1131    let mut lock = state_ptr.state.borrow_mut();
1132    if let Some(mut callback) = lock.callbacks.input.take() {
1133        let scale_factor = lock.scale_factor;
1134        drop(lock);
1135        let mut cursor_point = POINT {
1136            x: lparam.signed_loword().into(),
1137            y: lparam.signed_hiword().into(),
1138        };
1139        unsafe { ScreenToClient(handle, &mut cursor_point).ok().log_err() };
1140        let event = MouseUpEvent {
1141            button,
1142            position: logical_point(cursor_point.x as f32, cursor_point.y as f32, scale_factor),
1143            modifiers: current_modifiers(),
1144            click_count: 1,
1145        };
1146        let result = if callback(PlatformInput::MouseUp(event)).default_prevented {
1147            Some(0)
1148        } else {
1149            None
1150        };
1151        state_ptr.state.borrow_mut().callbacks.input = Some(callback);
1152        if result.is_some() {
1153            return result;
1154        }
1155    } else {
1156        drop(lock);
1157    }
1158
1159    let last_pressed = state_ptr.state.borrow_mut().nc_button_pressed.take();
1160    if button == MouseButton::Left && last_pressed.is_some() {
1161        let last_button = last_pressed.unwrap();
1162        let mut handled = false;
1163        match wparam.0 as u32 {
1164            HTMINBUTTON => {
1165                if last_button == HTMINBUTTON {
1166                    unsafe { ShowWindowAsync(handle, SW_MINIMIZE).ok().log_err() };
1167                    handled = true;
1168                }
1169            }
1170            HTMAXBUTTON => {
1171                if last_button == HTMAXBUTTON {
1172                    if state_ptr.state.borrow().is_maximized() {
1173                        unsafe { ShowWindowAsync(handle, SW_NORMAL).ok().log_err() };
1174                    } else {
1175                        unsafe { ShowWindowAsync(handle, SW_MAXIMIZE).ok().log_err() };
1176                    }
1177                    handled = true;
1178                }
1179            }
1180            HTCLOSE => {
1181                if last_button == HTCLOSE {
1182                    unsafe {
1183                        PostMessageW(Some(handle), WM_CLOSE, WPARAM::default(), LPARAM::default())
1184                            .log_err()
1185                    };
1186                    handled = true;
1187                }
1188            }
1189            _ => {}
1190        };
1191        if handled {
1192            return Some(0);
1193        }
1194    }
1195
1196    None
1197}
1198
1199fn handle_cursor_changed(lparam: LPARAM, state_ptr: Rc<WindowsWindowStatePtr>) -> Option<isize> {
1200    let mut state = state_ptr.state.borrow_mut();
1201    let had_cursor = state.current_cursor.is_some();
1202
1203    state.current_cursor = if lparam.0 == 0 {
1204        None
1205    } else {
1206        Some(HCURSOR(lparam.0 as _))
1207    };
1208
1209    if had_cursor != state.current_cursor.is_some() {
1210        unsafe { SetCursor(state.current_cursor) };
1211    }
1212
1213    Some(0)
1214}
1215
1216fn handle_set_cursor(lparam: LPARAM, state_ptr: Rc<WindowsWindowStatePtr>) -> Option<isize> {
1217    if matches!(
1218        lparam.loword() as u32,
1219        HTLEFT | HTRIGHT | HTTOP | HTTOPLEFT | HTTOPRIGHT | HTBOTTOM | HTBOTTOMLEFT | HTBOTTOMRIGHT
1220    ) {
1221        return None;
1222    }
1223    unsafe {
1224        SetCursor(state_ptr.state.borrow().current_cursor);
1225    };
1226    Some(1)
1227}
1228
1229fn handle_system_settings_changed(
1230    handle: HWND,
1231    lparam: LPARAM,
1232    state_ptr: Rc<WindowsWindowStatePtr>,
1233) -> Option<isize> {
1234    let mut lock = state_ptr.state.borrow_mut();
1235    let display = lock.display;
1236    // system settings
1237    lock.system_settings.update(display);
1238    // mouse double click
1239    lock.click_state.system_update();
1240    // window border offset
1241    lock.border_offset.update(handle).log_err();
1242    drop(lock);
1243
1244    // lParam is a pointer to a string that indicates the area containing the system parameter
1245    // that was changed.
1246    let parameter = PCWSTR::from_raw(lparam.0 as _);
1247    if unsafe { !parameter.is_null() && !parameter.is_empty() } {
1248        if let Some(parameter_string) = unsafe { parameter.to_string() }.log_err() {
1249            log::info!("System settings changed: {}", parameter_string);
1250            match parameter_string.as_str() {
1251                "ImmersiveColorSet" => {
1252                    handle_system_theme_changed(handle, state_ptr);
1253                }
1254                _ => {}
1255            }
1256        }
1257    }
1258
1259    // Force to trigger WM_NCCALCSIZE event to ensure that we handle auto hide
1260    // taskbar correctly.
1261    notify_frame_changed(handle);
1262    Some(0)
1263}
1264
1265fn handle_system_command(wparam: WPARAM, state_ptr: Rc<WindowsWindowStatePtr>) -> Option<isize> {
1266    if wparam.0 == SC_KEYMENU as usize {
1267        let mut lock = state_ptr.state.borrow_mut();
1268        if lock.system_key_handled {
1269            lock.system_key_handled = false;
1270            return Some(0);
1271        }
1272    }
1273    None
1274}
1275
1276fn handle_system_theme_changed(
1277    handle: HWND,
1278    state_ptr: Rc<WindowsWindowStatePtr>,
1279) -> Option<isize> {
1280    let mut callback = state_ptr
1281        .state
1282        .borrow_mut()
1283        .callbacks
1284        .appearance_changed
1285        .take()?;
1286    callback();
1287    state_ptr.state.borrow_mut().callbacks.appearance_changed = Some(callback);
1288    configure_dwm_dark_mode(handle);
1289    Some(0)
1290}
1291
1292fn handle_input_language_changed(
1293    lparam: LPARAM,
1294    state_ptr: Rc<WindowsWindowStatePtr>,
1295) -> Option<isize> {
1296    let thread = state_ptr.main_thread_id_win32;
1297    let validation = state_ptr.validation_number;
1298    unsafe {
1299        PostThreadMessageW(thread, WM_INPUTLANGCHANGE, WPARAM(validation), lparam).log_err();
1300    }
1301    Some(0)
1302}
1303
1304fn parse_syskeydown_msg_keystroke(wparam: WPARAM) -> Option<Keystroke> {
1305    let modifiers = current_modifiers();
1306    let vk_code = wparam.loword();
1307
1308    // on Windows, F10 can trigger this event, not just the alt key,
1309    // so when F10 was pressed, handle only it
1310    if !modifiers.alt {
1311        if vk_code == VK_F10.0 {
1312            let offset = vk_code - VK_F1.0;
1313            return Some(Keystroke {
1314                modifiers,
1315                key: format!("f{}", offset + 1),
1316                key_char: None,
1317            });
1318        } else {
1319            return None;
1320        }
1321    }
1322
1323    let key = match VIRTUAL_KEY(vk_code) {
1324        VK_BACK => "backspace",
1325        VK_RETURN => "enter",
1326        VK_TAB => "tab",
1327        VK_UP => "up",
1328        VK_DOWN => "down",
1329        VK_RIGHT => "right",
1330        VK_LEFT => "left",
1331        VK_HOME => "home",
1332        VK_END => "end",
1333        VK_PRIOR => "pageup",
1334        VK_NEXT => "pagedown",
1335        VK_BROWSER_BACK => "back",
1336        VK_BROWSER_FORWARD => "forward",
1337        VK_ESCAPE => "escape",
1338        VK_INSERT => "insert",
1339        VK_DELETE => "delete",
1340        VK_APPS => "menu",
1341        _ => {
1342            let basic_key = basic_vkcode_to_string(vk_code, modifiers);
1343            if basic_key.is_some() {
1344                return basic_key;
1345            } else {
1346                if vk_code >= VK_F1.0 && vk_code <= VK_F24.0 {
1347                    let offset = vk_code - VK_F1.0;
1348                    return Some(Keystroke {
1349                        modifiers,
1350                        key: format!("f{}", offset + 1),
1351                        key_char: None,
1352                    });
1353                } else {
1354                    return None;
1355                }
1356            }
1357        }
1358    }
1359    .to_owned();
1360
1361    Some(Keystroke {
1362        modifiers,
1363        key,
1364        key_char: None,
1365    })
1366}
1367
1368enum KeystrokeOrModifier {
1369    Keystroke(Keystroke),
1370    Modifier(Modifiers),
1371}
1372
1373fn parse_keystroke_from_vkey(wparam: WPARAM, is_keyup: bool) -> Option<KeystrokeOrModifier> {
1374    let vk_code = wparam.loword();
1375
1376    let modifiers = current_modifiers();
1377
1378    let key = match VIRTUAL_KEY(vk_code) {
1379        VK_BACK => "backspace",
1380        VK_RETURN => "enter",
1381        VK_TAB => "tab",
1382        VK_UP => "up",
1383        VK_DOWN => "down",
1384        VK_RIGHT => "right",
1385        VK_LEFT => "left",
1386        VK_HOME => "home",
1387        VK_END => "end",
1388        VK_PRIOR => "pageup",
1389        VK_NEXT => "pagedown",
1390        VK_BROWSER_BACK => "back",
1391        VK_BROWSER_FORWARD => "forward",
1392        VK_ESCAPE => "escape",
1393        VK_INSERT => "insert",
1394        VK_DELETE => "delete",
1395        VK_APPS => "menu",
1396        _ => {
1397            if is_modifier(VIRTUAL_KEY(vk_code)) {
1398                return Some(KeystrokeOrModifier::Modifier(modifiers));
1399            }
1400
1401            if modifiers.control || modifiers.alt || is_keyup {
1402                let basic_key = basic_vkcode_to_string(vk_code, modifiers);
1403                if let Some(basic_key) = basic_key {
1404                    return Some(KeystrokeOrModifier::Keystroke(basic_key));
1405                }
1406            }
1407
1408            if vk_code >= VK_F1.0 && vk_code <= VK_F24.0 {
1409                let offset = vk_code - VK_F1.0;
1410                return Some(KeystrokeOrModifier::Keystroke(Keystroke {
1411                    modifiers,
1412                    key: format!("f{}", offset + 1),
1413                    key_char: None,
1414                }));
1415            };
1416            return None;
1417        }
1418    }
1419    .to_owned();
1420
1421    Some(KeystrokeOrModifier::Keystroke(Keystroke {
1422        modifiers,
1423        key,
1424        key_char: None,
1425    }))
1426}
1427
1428fn parse_char_msg_keystroke(wparam: WPARAM) -> Option<Keystroke> {
1429    let first_char = char::from_u32((wparam.0 as u16).into())?;
1430    if first_char.is_control() {
1431        None
1432    } else {
1433        let mut modifiers = current_modifiers();
1434        // for characters that use 'shift' to type it is expected that the
1435        // shift is not reported if the uppercase/lowercase are the same and instead only the key is reported
1436        if first_char.to_ascii_uppercase() == first_char.to_ascii_lowercase() {
1437            modifiers.shift = false;
1438        }
1439        let key = match first_char {
1440            ' ' => "space".to_string(),
1441            first_char => first_char.to_lowercase().to_string(),
1442        };
1443        Some(Keystroke {
1444            modifiers,
1445            key,
1446            key_char: Some(first_char.to_string()),
1447        })
1448    }
1449}
1450
1451fn parse_ime_compostion_string(ctx: HIMC) -> Option<(String, usize)> {
1452    unsafe {
1453        let string_len = ImmGetCompositionStringW(ctx, GCS_COMPSTR, None, 0);
1454        if string_len >= 0 {
1455            let mut buffer = vec![0u8; string_len as usize + 2];
1456            ImmGetCompositionStringW(
1457                ctx,
1458                GCS_COMPSTR,
1459                Some(buffer.as_mut_ptr() as _),
1460                string_len as _,
1461            );
1462            let wstring = std::slice::from_raw_parts::<u16>(
1463                buffer.as_mut_ptr().cast::<u16>(),
1464                string_len as usize / 2,
1465            );
1466            let string = String::from_utf16_lossy(wstring);
1467            Some((string, string_len as usize / 2))
1468        } else {
1469            None
1470        }
1471    }
1472}
1473
1474#[inline]
1475fn retrieve_composition_cursor_position(ctx: HIMC) -> usize {
1476    unsafe { ImmGetCompositionStringW(ctx, GCS_CURSORPOS, None, 0) as usize }
1477}
1478
1479fn parse_ime_compostion_result(ctx: HIMC) -> Option<String> {
1480    unsafe {
1481        let string_len = ImmGetCompositionStringW(ctx, GCS_RESULTSTR, None, 0);
1482        if string_len >= 0 {
1483            let mut buffer = vec![0u8; string_len as usize + 2];
1484            ImmGetCompositionStringW(
1485                ctx,
1486                GCS_RESULTSTR,
1487                Some(buffer.as_mut_ptr() as _),
1488                string_len as _,
1489            );
1490            let wstring = std::slice::from_raw_parts::<u16>(
1491                buffer.as_mut_ptr().cast::<u16>(),
1492                string_len as usize / 2,
1493            );
1494            let string = String::from_utf16_lossy(wstring);
1495            Some(string)
1496        } else {
1497            None
1498        }
1499    }
1500}
1501
1502fn basic_vkcode_to_string(code: u16, modifiers: Modifiers) -> Option<Keystroke> {
1503    let mapped_code = unsafe { MapVirtualKeyW(code as u32, MAPVK_VK_TO_CHAR) };
1504
1505    let key = match mapped_code {
1506        0 => None,
1507        raw_code => char::from_u32(raw_code),
1508    }?
1509    .to_ascii_lowercase();
1510
1511    let key = if matches!(code as u32, 112..=135) {
1512        format!("f{key}")
1513    } else {
1514        key.to_string()
1515    };
1516
1517    Some(Keystroke {
1518        modifiers,
1519        key,
1520        key_char: None,
1521    })
1522}
1523
1524#[inline]
1525fn is_virtual_key_pressed(vkey: VIRTUAL_KEY) -> bool {
1526    unsafe { GetKeyState(vkey.0 as i32) < 0 }
1527}
1528
1529fn is_modifier(virtual_key: VIRTUAL_KEY) -> bool {
1530    matches!(
1531        virtual_key,
1532        VK_CONTROL | VK_MENU | VK_SHIFT | VK_LWIN | VK_RWIN
1533    )
1534}
1535
1536#[inline]
1537pub(crate) fn current_modifiers() -> Modifiers {
1538    Modifiers {
1539        control: is_virtual_key_pressed(VK_CONTROL),
1540        alt: is_virtual_key_pressed(VK_MENU),
1541        shift: is_virtual_key_pressed(VK_SHIFT),
1542        platform: is_virtual_key_pressed(VK_LWIN) || is_virtual_key_pressed(VK_RWIN),
1543        function: false,
1544    }
1545}
1546
1547fn get_client_area_insets(
1548    handle: HWND,
1549    is_maximized: bool,
1550    windows_version: WindowsVersion,
1551) -> RECT {
1552    // For maximized windows, Windows outdents the window rect from the screen's client rect
1553    // by `frame_thickness` on each edge, meaning `insets` must contain `frame_thickness`
1554    // on all sides (including the top) to avoid the client area extending onto adjacent
1555    // monitors.
1556    //
1557    // For non-maximized windows, things become complicated:
1558    //
1559    // - On Windows 10
1560    // The top inset must be zero, since if there is any nonclient area, Windows will draw
1561    // a full native titlebar outside the client area. (This doesn't occur in the maximized
1562    // case.)
1563    //
1564    // - On Windows 11
1565    // The top inset is calculated using an empirical formula that I derived through various
1566    // tests. Without this, the top 1-2 rows of pixels in our window would be obscured.
1567    let dpi = unsafe { GetDpiForWindow(handle) };
1568    let frame_thickness = get_frame_thickness(dpi);
1569    let top_insets = if is_maximized {
1570        frame_thickness
1571    } else {
1572        match windows_version {
1573            WindowsVersion::Win10 => 0,
1574            WindowsVersion::Win11 => (dpi as f32 / USER_DEFAULT_SCREEN_DPI as f32).round() as i32,
1575        }
1576    };
1577    RECT {
1578        left: frame_thickness,
1579        top: top_insets,
1580        right: frame_thickness,
1581        bottom: frame_thickness,
1582    }
1583}
1584
1585// there is some additional non-visible space when talking about window
1586// borders on Windows:
1587// - SM_CXSIZEFRAME: The resize handle.
1588// - SM_CXPADDEDBORDER: Additional border space that isn't part of the resize handle.
1589fn get_frame_thickness(dpi: u32) -> i32 {
1590    let resize_frame_thickness = unsafe { GetSystemMetricsForDpi(SM_CXSIZEFRAME, dpi) };
1591    let padding_thickness = unsafe { GetSystemMetricsForDpi(SM_CXPADDEDBORDER, dpi) };
1592    resize_frame_thickness + padding_thickness
1593}
1594
1595fn notify_frame_changed(handle: HWND) {
1596    unsafe {
1597        SetWindowPos(
1598            handle,
1599            None,
1600            0,
1601            0,
1602            0,
1603            0,
1604            SWP_FRAMECHANGED
1605                | SWP_NOACTIVATE
1606                | SWP_NOCOPYBITS
1607                | SWP_NOMOVE
1608                | SWP_NOOWNERZORDER
1609                | SWP_NOREPOSITION
1610                | SWP_NOSENDCHANGING
1611                | SWP_NOSIZE
1612                | SWP_NOZORDER,
1613        )
1614        .log_err();
1615    }
1616}
1617
1618fn start_tracking_mouse(
1619    handle: HWND,
1620    state_ptr: &Rc<WindowsWindowStatePtr>,
1621    flags: TRACKMOUSEEVENT_FLAGS,
1622) {
1623    let mut lock = state_ptr.state.borrow_mut();
1624    if !lock.hovered {
1625        lock.hovered = true;
1626        unsafe {
1627            TrackMouseEvent(&mut TRACKMOUSEEVENT {
1628                cbSize: std::mem::size_of::<TRACKMOUSEEVENT>() as u32,
1629                dwFlags: flags,
1630                hwndTrack: handle,
1631                dwHoverTime: HOVER_DEFAULT,
1632            })
1633            .log_err()
1634        };
1635        if let Some(mut callback) = lock.callbacks.hovered_status_change.take() {
1636            drop(lock);
1637            callback(true);
1638            state_ptr.state.borrow_mut().callbacks.hovered_status_change = Some(callback);
1639        }
1640    }
1641}
1642
1643fn with_input_handler<F, R>(state_ptr: &Rc<WindowsWindowStatePtr>, f: F) -> Option<R>
1644where
1645    F: FnOnce(&mut PlatformInputHandler) -> R,
1646{
1647    let mut input_handler = state_ptr.state.borrow_mut().input_handler.take()?;
1648    let result = f(&mut input_handler);
1649    state_ptr.state.borrow_mut().input_handler = Some(input_handler);
1650    Some(result)
1651}
1652
1653fn with_input_handler_and_scale_factor<F, R>(
1654    state_ptr: &Rc<WindowsWindowStatePtr>,
1655    f: F,
1656) -> Option<R>
1657where
1658    F: FnOnce(&mut PlatformInputHandler, f32) -> Option<R>,
1659{
1660    let mut lock = state_ptr.state.borrow_mut();
1661    let mut input_handler = lock.input_handler.take()?;
1662    let scale_factor = lock.scale_factor;
1663    drop(lock);
1664    let result = f(&mut input_handler, scale_factor);
1665    state_ptr.state.borrow_mut().input_handler = Some(input_handler);
1666    result
1667}