use std::{
collections::VecDeque,
fmt::{self, Debug},
hint::unreachable_unchecked,
mem,
rc::Rc,
sync::{
atomic::{AtomicBool, Ordering},
Mutex, MutexGuard,
},
time::Instant,
};
use cocoa::{
appkit::{NSApp, NSEventType::NSApplicationDefined, NSWindow},
base::{id, nil},
foundation::{NSAutoreleasePool, NSPoint, NSSize},
};
use objc::runtime::YES;
use crate::{
dpi::LogicalSize,
event::{Event, StartCause, WindowEvent},
event_loop::{ControlFlow, EventLoopWindowTarget as RootWindowTarget},
platform_impl::platform::{
event::{EventProxy, EventWrapper},
observer::EventLoopWaker,
util::{IdRef, Never},
window::get_window_id,
},
window::WindowId,
};
lazy_static! {
static ref HANDLER: Handler = Default::default();
}
impl<'a, Never> Event<'a, Never> {
fn userify<T: 'static>(self) -> Event<'a, T> {
self.map_nonuser_event()
.unwrap_or_else(|_| unsafe { unreachable_unchecked() })
}
}
pub trait EventHandler: Debug {
fn handle_nonuser_event(&mut self, event: Event<'_, Never>, control_flow: &mut ControlFlow);
fn handle_user_events(&mut self, control_flow: &mut ControlFlow);
}
struct EventLoopHandler<T: 'static> {
callback: Box<dyn FnMut(Event<'_, T>, &RootWindowTarget<T>, &mut ControlFlow)>,
will_exit: bool,
window_target: Rc<RootWindowTarget<T>>,
}
impl<T> Debug for EventLoopHandler<T> {
fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
formatter
.debug_struct("EventLoopHandler")
.field("window_target", &self.window_target)
.finish()
}
}
impl<T> EventHandler for EventLoopHandler<T> {
fn handle_nonuser_event(&mut self, event: Event<'_, Never>, control_flow: &mut ControlFlow) {
(self.callback)(event.userify(), &self.window_target, control_flow);
self.will_exit |= *control_flow == ControlFlow::Exit;
if self.will_exit {
*control_flow = ControlFlow::Exit;
}
}
fn handle_user_events(&mut self, control_flow: &mut ControlFlow) {
let mut will_exit = self.will_exit;
for event in self.window_target.p.receiver.try_iter() {
(self.callback)(Event::UserEvent(event), &self.window_target, control_flow);
will_exit |= *control_flow == ControlFlow::Exit;
if will_exit {
*control_flow = ControlFlow::Exit;
}
}
self.will_exit = will_exit;
}
}
#[derive(Default)]
struct Handler {
ready: AtomicBool,
in_callback: AtomicBool,
dialog_is_closing: AtomicBool,
control_flow: Mutex<ControlFlow>,
control_flow_prev: Mutex<ControlFlow>,
start_time: Mutex<Option<Instant>>,
callback: Mutex<Option<Box<dyn EventHandler>>>,
pending_events: Mutex<VecDeque<EventWrapper>>,
pending_redraw: Mutex<Vec<WindowId>>,
waker: Mutex<EventLoopWaker>,
}
unsafe impl Send for Handler {}
unsafe impl Sync for Handler {}
impl Handler {
fn events(&self) -> MutexGuard<'_, VecDeque<EventWrapper>> {
self.pending_events.lock().unwrap()
}
fn redraw<'a>(&'a self) -> MutexGuard<'a, Vec<WindowId>> {
self.pending_redraw.lock().unwrap()
}
fn waker(&self) -> MutexGuard<'_, EventLoopWaker> {
self.waker.lock().unwrap()
}
fn is_ready(&self) -> bool {
self.ready.load(Ordering::Acquire)
}
fn set_ready(&self) {
self.ready.store(true, Ordering::Release);
}
fn should_exit(&self) -> bool {
*self.control_flow.lock().unwrap() == ControlFlow::Exit
}
fn get_control_flow_and_update_prev(&self) -> ControlFlow {
let control_flow = self.control_flow.lock().unwrap();
*self.control_flow_prev.lock().unwrap() = *control_flow;
*control_flow
}
fn get_old_and_new_control_flow(&self) -> (ControlFlow, ControlFlow) {
let old = *self.control_flow_prev.lock().unwrap();
let new = *self.control_flow.lock().unwrap();
(old, new)
}
fn get_start_time(&self) -> Option<Instant> {
*self.start_time.lock().unwrap()
}
fn update_start_time(&self) {
*self.start_time.lock().unwrap() = Some(Instant::now());
}
fn take_events(&self) -> VecDeque<EventWrapper> {
mem::replace(&mut *self.events(), Default::default())
}
fn should_redraw(&self) -> Vec<WindowId> {
mem::replace(&mut *self.redraw(), Default::default())
}
fn get_in_callback(&self) -> bool {
self.in_callback.load(Ordering::Acquire)
}
fn set_in_callback(&self, in_callback: bool) {
self.in_callback.store(in_callback, Ordering::Release);
}
fn handle_nonuser_event(&self, wrapper: EventWrapper) {
if let Some(ref mut callback) = *self.callback.lock().unwrap() {
match wrapper {
EventWrapper::StaticEvent(event) => {
callback.handle_nonuser_event(event, &mut *self.control_flow.lock().unwrap())
}
EventWrapper::EventProxy(proxy) => self.handle_proxy(proxy, callback),
}
}
}
fn handle_user_events(&self) {
if let Some(ref mut callback) = *self.callback.lock().unwrap() {
callback.handle_user_events(&mut *self.control_flow.lock().unwrap());
}
}
fn handle_scale_factor_changed_event(
&self,
callback: &mut Box<dyn EventHandler + 'static>,
ns_window: IdRef,
suggested_size: LogicalSize<f64>,
scale_factor: f64,
) {
let mut size = suggested_size.to_physical(scale_factor);
let new_inner_size = &mut size;
let event = Event::WindowEvent {
window_id: WindowId(get_window_id(*ns_window)),
event: WindowEvent::ScaleFactorChanged {
scale_factor,
new_inner_size,
},
};
callback.handle_nonuser_event(event, &mut *self.control_flow.lock().unwrap());
let physical_size = *new_inner_size;
let logical_size = physical_size.to_logical(scale_factor);
let size = NSSize::new(logical_size.width, logical_size.height);
unsafe { NSWindow::setContentSize_(*ns_window, size) };
}
fn handle_proxy(&self, proxy: EventProxy, callback: &mut Box<dyn EventHandler + 'static>) {
match proxy {
EventProxy::DpiChangedProxy {
ns_window,
suggested_size,
scale_factor,
} => self.handle_scale_factor_changed_event(
callback,
ns_window,
suggested_size,
scale_factor,
),
}
}
}
pub static INTERRUPT_EVENT_LOOP_EXIT: AtomicBool = AtomicBool::new(false);
pub enum AppState {}
impl AppState {
pub unsafe fn set_callback<F, T>(callback: F, window_target: Rc<RootWindowTarget<T>>)
where
F: FnMut(Event<'_, T>, &RootWindowTarget<T>, &mut ControlFlow),
{
*HANDLER.callback.lock().unwrap() = Some(Box::new(EventLoopHandler {
callback: mem::transmute::<
Box<dyn FnMut(Event<'_, T>, &RootWindowTarget<T>, &mut ControlFlow)>,
Box<dyn FnMut(Event<'_, T>, &RootWindowTarget<T>, &mut ControlFlow)>,
>(Box::new(callback)),
will_exit: false,
window_target,
}));
}
pub fn exit() {
HANDLER.set_in_callback(true);
HANDLER.handle_nonuser_event(EventWrapper::StaticEvent(Event::LoopDestroyed));
HANDLER.set_in_callback(false);
HANDLER.callback.lock().unwrap().take();
}
pub fn launched() {
HANDLER.set_ready();
HANDLER.waker().start();
HANDLER.set_in_callback(true);
HANDLER.handle_nonuser_event(EventWrapper::StaticEvent(Event::NewEvents(
StartCause::Init,
)));
HANDLER.set_in_callback(false);
}
pub fn wakeup() {
if !HANDLER.is_ready() {
return;
}
let start = HANDLER.get_start_time().unwrap();
let cause = match HANDLER.get_control_flow_and_update_prev() {
ControlFlow::Poll => StartCause::Poll,
ControlFlow::Wait => StartCause::WaitCancelled {
start,
requested_resume: None,
},
ControlFlow::WaitUntil(requested_resume) => {
if Instant::now() >= requested_resume {
StartCause::ResumeTimeReached {
start,
requested_resume,
}
} else {
StartCause::WaitCancelled {
start,
requested_resume: Some(requested_resume),
}
}
}
ControlFlow::Exit => StartCause::Poll, };
HANDLER.set_in_callback(true);
HANDLER.handle_nonuser_event(EventWrapper::StaticEvent(Event::NewEvents(cause)));
HANDLER.set_in_callback(false);
}
pub fn queue_redraw(window_id: WindowId) {
let mut pending_redraw = HANDLER.redraw();
if !pending_redraw.contains(&window_id) {
pending_redraw.push(window_id);
}
}
pub fn queue_event(wrapper: EventWrapper) {
if !unsafe { msg_send![class!(NSThread), isMainThread] } {
panic!("Event queued from different thread: {:#?}", wrapper);
}
HANDLER.events().push_back(wrapper);
}
pub fn queue_events(mut wrappers: VecDeque<EventWrapper>) {
if !unsafe { msg_send![class!(NSThread), isMainThread] } {
panic!("Events queued from different thread: {:#?}", wrappers);
}
HANDLER.events().append(&mut wrappers);
}
pub fn cleared() {
if !HANDLER.is_ready() {
return;
}
if !HANDLER.get_in_callback() {
HANDLER.set_in_callback(true);
HANDLER.handle_user_events();
for event in HANDLER.take_events() {
HANDLER.handle_nonuser_event(event);
}
HANDLER.handle_nonuser_event(EventWrapper::StaticEvent(Event::MainEventsCleared));
for window_id in HANDLER.should_redraw() {
HANDLER.handle_nonuser_event(EventWrapper::StaticEvent(Event::RedrawRequested(
window_id,
)));
}
HANDLER.handle_nonuser_event(EventWrapper::StaticEvent(Event::RedrawEventsCleared));
HANDLER.set_in_callback(false);
}
if HANDLER.should_exit() {
unsafe {
let app: id = NSApp();
let windows: id = msg_send![app, windows];
let window: id = msg_send![windows, objectAtIndex:0];
let window_count: usize = msg_send![windows, count];
assert_ne!(window, nil);
let dialog_open = if window_count > 1 {
let dialog: id = msg_send![windows, lastObject];
let is_main_window: bool = msg_send![dialog, isMainWindow];
msg_send![dialog, isVisible] && !is_main_window
} else {
false
};
let dialog_is_closing = HANDLER.dialog_is_closing.load(Ordering::SeqCst);
let pool = NSAutoreleasePool::new(nil);
if !INTERRUPT_EVENT_LOOP_EXIT.load(Ordering::SeqCst)
&& !dialog_open
&& !dialog_is_closing
{
let _: () = msg_send![app, stop: nil];
let dummy_event: id = msg_send![class!(NSEvent),
otherEventWithType: NSApplicationDefined
location: NSPoint::new(0.0, 0.0)
modifierFlags: 0
timestamp: 0
windowNumber: 0
context: nil
subtype: 0
data1: 0
data2: 0
];
let _: () = msg_send![window, postEvent: dummy_event atStart: YES];
}
pool.drain();
let window_has_focus = msg_send![window, isKeyWindow];
if !dialog_open && window_has_focus && dialog_is_closing {
HANDLER.dialog_is_closing.store(false, Ordering::SeqCst);
}
if dialog_open {
HANDLER.dialog_is_closing.store(true, Ordering::SeqCst);
}
};
}
HANDLER.update_start_time();
match HANDLER.get_old_and_new_control_flow() {
(ControlFlow::Exit, _) | (_, ControlFlow::Exit) => (),
(old, new) if old == new => (),
(_, ControlFlow::Wait) => HANDLER.waker().stop(),
(_, ControlFlow::WaitUntil(instant)) => HANDLER.waker().start_at(instant),
(_, ControlFlow::Poll) => HANDLER.waker().start(),
}
}
}