Something something games

src/games/lib/control/Control.ts

@@ -0,0 +1,87 @@
+type state = 'down' | 'up';
+
+// - TODO - Pull this from the actual game creating the controls
+const GameControls = {
+  down: 'down',
+  up: 'up',
+  left: 'left',
+  right: 'right',
+  shift: 'shift',
+  ' ': ' ',
+} as const;
+
+/**
+ * Abstraction for game controls, the game should say what controls it expects and then we can remap the actual controls separately.  
+ * i.e. Both "ArrowDown" and "Down" from the keyboard listener should be the games "down" event.  
+ * Also handles when the keys are pressed or not.
+ */
+class Control {
+  readonly gameControls = GameControls;
+  private _controlMap: { [key: string]: keyof typeof GameControls } = {
+    ArrowDown: GameControls.down,
+    Down: GameControls.down,
+    ArrowUp: GameControls.up,
+    Up: GameControls.up,
+    ArrowLeft: GameControls.left,
+    Left: GameControls.left,
+    ArrowRight: GameControls.right,
+    Right: GameControls.right,
+    Shift: GameControls.shift,
+    ' ': GameControls[' '],
+  };
+
+  private _controlState: Map<keyof typeof GameControls, {
+    state: state,
+
+    consumed: boolean
+  }> = new Map();
+
+  constructor() {
+    this._setKeys();
+    window.addEventListener('keydown', (event) => {
+      if (this._controlState.get(this._controlMap[event.key])?.state !== 'down') {
+        this._controlState.set(this._controlMap[event.key], { state: 'down', consumed: false });
+      }
+    });
+
+    window.addEventListener('keyup', (event) => {
+      if (this._controlState.get(this._controlMap[event.key])?.state !== 'up') {
+        this._controlState.set(this._controlMap[event.key], { state: 'up', consumed: false });
+      }
+    });
+  }
+
+  /**
+   * - TODO
+   */
+  private _setKeys(): void {
+    Object.keys(GameControls).forEach((key) => {
+      this._controlState.set(key as keyof typeof GameControls, { state: 'up', consumed: false });
+    });
+  }
+
+  /**
+   * - TODO
+   *
+   * @param key - TODO
+   */
+  isDown(key: keyof typeof GameControls): boolean {
+    return this._controlState.get(key)?.state === 'down';
+  }
+
+  /**
+   * Consume a down key event once
+   * 
+   * @param key  - TODO
+   */
+  onceDown(key: keyof typeof GameControls): boolean {
+    const keyState = this._controlState.get(key);
+    if (keyState && keyState.state === 'down' && !keyState.consumed) {
+      keyState.consumed = true;
+      return true;
+    }
+    return false;
+  }
+}
+
+export default Control;