Add keyboard handling

It's very rudimentary now -- allowing movement only.

dose-response.js

@@ -13,6 +13,14 @@ ctx.font = '16px arial';
 
 var wasm_instance;
 var gamestate_ptr;
+var keyqueue = [];
+
+const keymap = {
+  ArrowUp: 0,
+  ArrowDown: 1,
+  ArrowLeft: 2,
+  ArrowRight: 3
+};
 
 
 fetch('target/wasm32-unknown-unknown/release/dose-response.wasm')
@@ -47,6 +55,12 @@ fetch('target/wasm32-unknown-unknown/release/dose-response.wasm')
   }))
 
   .then(results => {
+
+    document.addEventListener('keydown', (event) => {
+      console.log(event);
+      keyqueue.push(event);
+    });
+
     console.log("The game has finished.");
     console.log(results);
     console.log(results.module);
@@ -60,7 +74,20 @@ fetch('target/wasm32-unknown-unknown/release/dose-response.wasm')
 
     function update() {
       //window.requestAnimationFrame(update);
+      //window.setTimeout(update, 100);
       //console.log("calling update");
+      for(let key of keyqueue) {
+        var key_code = -1;
+        if(key.key in keymap) {
+          key_code = keymap[key.key];
+        }
+        wasm_instance.exports.key_pressed(
+          gamestate_ptr,
+          key_code,
+          key.ctrlKey, key.altKey, key.shiftKey, key.location);
+      }
+      keyqueue = [];
+
       results.instance.exports.update(gamestate_ptr);
       //console.log("called update");
     }

src/main.rs

@@ -432,6 +432,33 @@ pub fn update(state_ptr: *mut State) {
     std::mem::forget(state);
 }
 
+#[no_mangle]
+pub extern "C" fn key_pressed(
+    state_ptr: *mut State,
+    external_code: i32,
+    ctrl: bool, alt: bool, shift: bool, location: i32
+)
+{
+    use std::ffi::CStr;
+
+    #[allow(unsafe_code)]
+    let mut state: Box<State> = unsafe { Box::from_raw(state_ptr) };
+
+    let code = match external_code {
+        0 => Some(keys::KeyCode::Up),
+        1 => Some(keys::KeyCode::Down),
+        2 => Some(keys::KeyCode::Left),
+        3 => Some(keys::KeyCode::Right),
+        _ => None,
+    };
+    if let Some(code) = code {
+        state.keys.push(keys::Key { code, alt, ctrl, shift});
+    }
+
+    std::mem::forget(state);
+
+}
+
 
 fn main() {
     // NOTE: at our current font, the height of 43 is the maximum