Implement web_sys::Canvas event listeners

src/platform_impl/web/web_sys/timeout.rs

@@ -1,12 +1,40 @@
 use std::time::Duration;
+use wasm_bindgen::closure::Closure;
+use wasm_bindgen::JsCast;
 
-#[derive(Debug, Clone, Copy)]
-pub struct Timeout {}
+#[derive(Debug)]
+pub struct Timeout {
+    handle: i32,
+    _closure: Closure<FnMut()>,
+}
 
 impl Timeout {
-    pub fn new<F>(f: F, duration: Duration) -> Timeout {
-        Timeout {}
-    }
+    pub fn new<F>(f: F, duration: Duration) -> Timeout
+    where
+        F: 'static + FnMut(),
+    {
+        let window = web_sys::window().expect("Failed to obtain window");
 
-    pub fn clear(self) {}
+        let closure = Closure::wrap(Box::new(f) as Box<dyn FnMut()>);
+
+        let handle = window
+            .set_timeout_with_callback_and_timeout_and_arguments_0(
+                &closure.as_ref().unchecked_ref(),
+                duration.as_millis() as i32,
+            )
+            .expect("Failed to set timeout");
+
+        Timeout {
+            handle,
+            _closure: closure,
+        }
+    }
+}
+
+impl Drop for Timeout {
+    fn drop(&mut self) {
+        let window = web_sys::window().expect("Failed to obtain window");
+
+        window.clear_timeout_with_handle(self.handle);
+    }
 }