event.rs

  1use crate::{
  2    geometry::vector::vec2f,
  3    keymap_matcher::Keystroke,
  4    platform::{
  5        Event, KeyDownEvent, KeyUpEvent, Modifiers, ModifiersChangedEvent, MouseButton,
  6        MouseButtonEvent, MouseExitedEvent, MouseMovedEvent, NavigationDirection, ScrollDelta,
  7        ScrollWheelEvent, TouchPhase,
  8    },
  9};
 10use cocoa::{
 11    appkit::{NSEvent, NSEventModifierFlags, NSEventPhase, NSEventType},
 12    base::{id, YES},
 13    foundation::NSString as _,
 14};
 15use core_graphics::{
 16    event::{CGEvent, CGEventFlags, CGKeyCode},
 17    event_source::{CGEventSource, CGEventSourceStateID},
 18};
 19use ctor::ctor;
 20use foreign_types::ForeignType;
 21use objc::{class, msg_send, sel, sel_impl};
 22use std::{borrow::Cow, ffi::CStr, mem, os::raw::c_char, ptr};
 23
 24const BACKSPACE_KEY: u16 = 0x7f;
 25const SPACE_KEY: u16 = b' ' as u16;
 26const ENTER_KEY: u16 = 0x0d;
 27const NUMPAD_ENTER_KEY: u16 = 0x03;
 28const ESCAPE_KEY: u16 = 0x1b;
 29const TAB_KEY: u16 = 0x09;
 30const SHIFT_TAB_KEY: u16 = 0x19;
 31
 32static mut EVENT_SOURCE: core_graphics::sys::CGEventSourceRef = ptr::null_mut();
 33
 34#[ctor]
 35unsafe fn build_event_source() {
 36    let source = CGEventSource::new(CGEventSourceStateID::Private).unwrap();
 37    EVENT_SOURCE = source.as_ptr();
 38    mem::forget(source);
 39}
 40
 41pub fn key_to_native(key: &str) -> Cow<str> {
 42    use cocoa::appkit::*;
 43    let code = match key {
 44        "space" => SPACE_KEY,
 45        "backspace" => BACKSPACE_KEY,
 46        "up" => NSUpArrowFunctionKey,
 47        "down" => NSDownArrowFunctionKey,
 48        "left" => NSLeftArrowFunctionKey,
 49        "right" => NSRightArrowFunctionKey,
 50        "pageup" => NSPageUpFunctionKey,
 51        "pagedown" => NSPageDownFunctionKey,
 52        "home" => NSHomeFunctionKey,
 53        "end" => NSEndFunctionKey,
 54        "delete" => NSDeleteFunctionKey,
 55        "f1" => NSF1FunctionKey,
 56        "f2" => NSF2FunctionKey,
 57        "f3" => NSF3FunctionKey,
 58        "f4" => NSF4FunctionKey,
 59        "f5" => NSF5FunctionKey,
 60        "f6" => NSF6FunctionKey,
 61        "f7" => NSF7FunctionKey,
 62        "f8" => NSF8FunctionKey,
 63        "f9" => NSF9FunctionKey,
 64        "f10" => NSF10FunctionKey,
 65        "f11" => NSF11FunctionKey,
 66        "f12" => NSF12FunctionKey,
 67        _ => return Cow::Borrowed(key),
 68    };
 69    Cow::Owned(String::from_utf16(&[code]).unwrap())
 70}
 71
 72unsafe fn read_modifiers(native_event: id) -> Modifiers {
 73    let modifiers = native_event.modifierFlags();
 74    let ctrl = modifiers.contains(NSEventModifierFlags::NSControlKeyMask);
 75    let alt = modifiers.contains(NSEventModifierFlags::NSAlternateKeyMask);
 76    let shift = modifiers.contains(NSEventModifierFlags::NSShiftKeyMask);
 77    let cmd = modifiers.contains(NSEventModifierFlags::NSCommandKeyMask);
 78    let fun = modifiers.contains(NSEventModifierFlags::NSFunctionKeyMask);
 79
 80    Modifiers {
 81        ctrl,
 82        alt,
 83        shift,
 84        cmd,
 85        fun,
 86    }
 87}
 88
 89impl Event {
 90    pub unsafe fn from_native(native_event: id, window_height: Option<f32>) -> Option<Self> {
 91        let event_type = native_event.eventType();
 92
 93        // Filter out event types that aren't in the NSEventType enum.
 94        // See https://github.com/servo/cocoa-rs/issues/155#issuecomment-323482792 for details.
 95        match event_type as u64 {
 96            0 | 21 | 32 | 33 | 35 | 36 | 37 => {
 97                return None;
 98            }
 99            _ => {}
100        }
101
102        match event_type {
103            NSEventType::NSFlagsChanged => Some(Self::ModifiersChanged(ModifiersChangedEvent {
104                modifiers: read_modifiers(native_event),
105            })),
106            NSEventType::NSKeyDown => Some(Self::KeyDown(KeyDownEvent {
107                keystroke: parse_keystroke(native_event),
108                is_held: native_event.isARepeat() == YES,
109            })),
110            NSEventType::NSKeyUp => Some(Self::KeyUp(KeyUpEvent {
111                keystroke: parse_keystroke(native_event),
112            })),
113            NSEventType::NSLeftMouseDown
114            | NSEventType::NSRightMouseDown
115            | NSEventType::NSOtherMouseDown => {
116                let button = match native_event.buttonNumber() {
117                    0 => MouseButton::Left,
118                    1 => MouseButton::Right,
119                    2 => MouseButton::Middle,
120                    3 => MouseButton::Navigate(NavigationDirection::Back),
121                    4 => MouseButton::Navigate(NavigationDirection::Forward),
122                    // Other mouse buttons aren't tracked currently
123                    _ => return None,
124                };
125                window_height.map(|window_height| {
126                    Self::MouseDown(MouseButtonEvent {
127                        button,
128                        position: vec2f(
129                            native_event.locationInWindow().x as f32,
130                            // MacOS screen coordinates are relative to bottom left
131                            window_height - native_event.locationInWindow().y as f32,
132                        ),
133                        modifiers: read_modifiers(native_event),
134                        click_count: native_event.clickCount() as usize,
135                    })
136                })
137            }
138            NSEventType::NSLeftMouseUp
139            | NSEventType::NSRightMouseUp
140            | NSEventType::NSOtherMouseUp => {
141                let button = match native_event.buttonNumber() {
142                    0 => MouseButton::Left,
143                    1 => MouseButton::Right,
144                    2 => MouseButton::Middle,
145                    3 => MouseButton::Navigate(NavigationDirection::Back),
146                    4 => MouseButton::Navigate(NavigationDirection::Forward),
147                    // Other mouse buttons aren't tracked currently
148                    _ => return None,
149                };
150
151                window_height.map(|window_height| {
152                    Self::MouseUp(MouseButtonEvent {
153                        button,
154                        position: vec2f(
155                            native_event.locationInWindow().x as f32,
156                            // MacOS view coordinates are relative to bottom left
157                            window_height - native_event.locationInWindow().y as f32,
158                        ),
159                        modifiers: read_modifiers(native_event),
160                        click_count: native_event.clickCount() as usize,
161                    })
162                })
163            }
164            NSEventType::NSScrollWheel => window_height.map(|window_height| {
165                let phase = match native_event.phase() {
166                    NSEventPhase::NSEventPhaseMayBegin | NSEventPhase::NSEventPhaseBegan => {
167                        Some(TouchPhase::Started)
168                    }
169                    NSEventPhase::NSEventPhaseEnded => Some(TouchPhase::Ended),
170                    _ => Some(TouchPhase::Moved),
171                };
172
173                let raw_data = vec2f(
174                    native_event.scrollingDeltaX() as f32,
175                    native_event.scrollingDeltaY() as f32,
176                );
177
178                let delta = if native_event.hasPreciseScrollingDeltas() == YES {
179                    ScrollDelta::Pixels(raw_data)
180                } else {
181                    ScrollDelta::Lines(raw_data)
182                };
183
184                Self::ScrollWheel(ScrollWheelEvent {
185                    position: vec2f(
186                        native_event.locationInWindow().x as f32,
187                        window_height - native_event.locationInWindow().y as f32,
188                    ),
189                    delta,
190                    phase,
191                    modifiers: read_modifiers(native_event),
192                })
193            }),
194            NSEventType::NSLeftMouseDragged
195            | NSEventType::NSRightMouseDragged
196            | NSEventType::NSOtherMouseDragged => {
197                let pressed_button = match native_event.buttonNumber() {
198                    0 => MouseButton::Left,
199                    1 => MouseButton::Right,
200                    2 => MouseButton::Middle,
201                    3 => MouseButton::Navigate(NavigationDirection::Back),
202                    4 => MouseButton::Navigate(NavigationDirection::Forward),
203                    // Other mouse buttons aren't tracked currently
204                    _ => return None,
205                };
206
207                window_height.map(|window_height| {
208                    Self::MouseMoved(MouseMovedEvent {
209                        pressed_button: Some(pressed_button),
210                        position: vec2f(
211                            native_event.locationInWindow().x as f32,
212                            window_height - native_event.locationInWindow().y as f32,
213                        ),
214                        modifiers: read_modifiers(native_event),
215                    })
216                })
217            }
218            NSEventType::NSMouseMoved => window_height.map(|window_height| {
219                Self::MouseMoved(MouseMovedEvent {
220                    position: vec2f(
221                        native_event.locationInWindow().x as f32,
222                        window_height - native_event.locationInWindow().y as f32,
223                    ),
224                    pressed_button: None,
225                    modifiers: read_modifiers(native_event),
226                })
227            }),
228            NSEventType::NSMouseExited => window_height.map(|window_height| {
229                Self::MouseExited(MouseExitedEvent {
230                    position: vec2f(
231                        native_event.locationInWindow().x as f32,
232                        window_height - native_event.locationInWindow().y as f32,
233                    ),
234                    pressed_button: None,
235                    modifiers: read_modifiers(native_event),
236                })
237            }),
238            _ => None,
239        }
240    }
241}
242
243unsafe fn parse_keystroke(native_event: id) -> Keystroke {
244    use cocoa::appkit::*;
245
246    let mut chars_ignoring_modifiers =
247        CStr::from_ptr(native_event.charactersIgnoringModifiers().UTF8String() as *mut c_char)
248            .to_str()
249            .unwrap()
250            .to_string();
251    let first_char = chars_ignoring_modifiers.chars().next().map(|ch| ch as u16);
252    let modifiers = native_event.modifierFlags();
253
254    let ctrl = modifiers.contains(NSEventModifierFlags::NSControlKeyMask);
255    let alt = modifiers.contains(NSEventModifierFlags::NSAlternateKeyMask);
256    let mut shift = modifiers.contains(NSEventModifierFlags::NSShiftKeyMask);
257    let cmd = modifiers.contains(NSEventModifierFlags::NSCommandKeyMask);
258    let function = modifiers.contains(NSEventModifierFlags::NSFunctionKeyMask)
259        && first_char.map_or(true, |ch| {
260            !(NSUpArrowFunctionKey..=NSModeSwitchFunctionKey).contains(&ch)
261        });
262
263    #[allow(non_upper_case_globals)]
264    let key = match first_char {
265        Some(SPACE_KEY) => "space".to_string(),
266        Some(BACKSPACE_KEY) => "backspace".to_string(),
267        Some(ENTER_KEY) | Some(NUMPAD_ENTER_KEY) => "enter".to_string(),
268        Some(ESCAPE_KEY) => "escape".to_string(),
269        Some(TAB_KEY) => "tab".to_string(),
270        Some(SHIFT_TAB_KEY) => "tab".to_string(),
271        Some(NSUpArrowFunctionKey) => "up".to_string(),
272        Some(NSDownArrowFunctionKey) => "down".to_string(),
273        Some(NSLeftArrowFunctionKey) => "left".to_string(),
274        Some(NSRightArrowFunctionKey) => "right".to_string(),
275        Some(NSPageUpFunctionKey) => "pageup".to_string(),
276        Some(NSPageDownFunctionKey) => "pagedown".to_string(),
277        Some(NSHomeFunctionKey) => "home".to_string(),
278        Some(NSEndFunctionKey) => "end".to_string(),
279        Some(NSDeleteFunctionKey) => "delete".to_string(),
280        Some(NSF1FunctionKey) => "f1".to_string(),
281        Some(NSF2FunctionKey) => "f2".to_string(),
282        Some(NSF3FunctionKey) => "f3".to_string(),
283        Some(NSF4FunctionKey) => "f4".to_string(),
284        Some(NSF5FunctionKey) => "f5".to_string(),
285        Some(NSF6FunctionKey) => "f6".to_string(),
286        Some(NSF7FunctionKey) => "f7".to_string(),
287        Some(NSF8FunctionKey) => "f8".to_string(),
288        Some(NSF9FunctionKey) => "f9".to_string(),
289        Some(NSF10FunctionKey) => "f10".to_string(),
290        Some(NSF11FunctionKey) => "f11".to_string(),
291        Some(NSF12FunctionKey) => "f12".to_string(),
292        _ => {
293            let mut chars_ignoring_modifiers_and_shift =
294                chars_for_modified_key(native_event.keyCode(), false, false);
295
296            // Honor ⌘ when Dvorak-QWERTY is used.
297            let chars_with_cmd = chars_for_modified_key(native_event.keyCode(), true, false);
298            if cmd && chars_ignoring_modifiers_and_shift != chars_with_cmd {
299                chars_ignoring_modifiers =
300                    chars_for_modified_key(native_event.keyCode(), true, shift);
301                chars_ignoring_modifiers_and_shift = chars_with_cmd;
302            }
303
304            if shift {
305                if chars_ignoring_modifiers_and_shift
306                    == chars_ignoring_modifiers.to_ascii_lowercase()
307                {
308                    chars_ignoring_modifiers_and_shift
309                } else if chars_ignoring_modifiers_and_shift != chars_ignoring_modifiers {
310                    shift = false;
311                    chars_ignoring_modifiers
312                } else {
313                    chars_ignoring_modifiers
314                }
315            } else {
316                chars_ignoring_modifiers
317            }
318        }
319    };
320
321    Keystroke {
322        ctrl,
323        alt,
324        shift,
325        cmd,
326        function,
327        key,
328    }
329}
330
331fn chars_for_modified_key(code: CGKeyCode, cmd: bool, shift: bool) -> String {
332    // Ideally, we would use `[NSEvent charactersByApplyingModifiers]` but that
333    // always returns an empty string with certain keyboards, e.g. Japanese. Synthesizing
334    // an event with the given flags instead lets us access `characters`, which always
335    // returns a valid string.
336    let source = unsafe { core_graphics::event_source::CGEventSource::from_ptr(EVENT_SOURCE) };
337    let event = CGEvent::new_keyboard_event(source.clone(), code, true).unwrap();
338    mem::forget(source);
339
340    let mut flags = CGEventFlags::empty();
341    if cmd {
342        flags |= CGEventFlags::CGEventFlagCommand;
343    }
344    if shift {
345        flags |= CGEventFlags::CGEventFlagShift;
346    }
347    event.set_flags(flags);
348
349    unsafe {
350        let event: id = msg_send![class!(NSEvent), eventWithCGEvent: &*event];
351        CStr::from_ptr(event.characters().UTF8String())
352            .to_str()
353            .unwrap()
354            .to_string()
355    }
356}