event.rs

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