static/js/input.js

// keyboard + mouse input. GAMEPLAY_FLOW.md controls.
export const keys = { up: false, down: false, left: false, right: false };
const handlers = { interact: [], gift: [], escape: [], option: [], mute: [] };

export function on(name, fn) { handlers[name].push(fn); }
function fire(name, arg) { handlers[name].forEach((fn) => fn(arg)); }
// touch controls fire the same handlers as the keyboard (see touch.js)
export function emit(name, arg) { fire(name, arg); }

const KEYMAP = {
  KeyW: "up", ArrowUp: "up",
  KeyS: "down", ArrowDown: "down",
  KeyA: "left", ArrowLeft: "left",
  KeyD: "right", ArrowRight: "right",
};

export let typingMode = false;
export function setTyping(v) {
  typingMode = v;
  Object.keys(keys).forEach((k) => (keys[k] = false));
}

window.addEventListener("keydown", (e) => {
  if (typingMode) return; // text input owns the keyboard
  if (KEYMAP[e.code]) { keys[KEYMAP[e.code]] = true; e.preventDefault(); return; }
  if (e.code === "Space" || e.code === "Enter") { fire("interact"); e.preventDefault(); }
  else if (e.code === "KeyG") fire("gift");
  else if (e.code === "Escape") fire("escape");
  else if (e.code === "Digit1") fire("option", "a");
  else if (e.code === "Digit2") fire("option", "b");
  else if (e.code === "KeyM") fire("mute");
});

window.addEventListener("keyup", (e) => {
  if (KEYMAP[e.code]) keys[KEYMAP[e.code]] = false;
});

// click-to-move: main.js registers the stage and receives world coords
export function bindStageClick(stageEl, fn) {
  stageEl.addEventListener("click", (e) => {
    const r = stageEl.getBoundingClientRect();
    const x = ((e.clientX - r.left) / r.width) * 640;
    const y = ((e.clientY - r.top) / r.height) * 480;
    fn(x, y);
  });
}