import { useEffect, useRef } from "preact/hooks";

const REPEAT_DELAY = 400;
const REPEAT_INTERVAL = 150;

const BTN_A = 0;
const BTN_B = 1;
const BTN_X = 2;
const BTN_Y = 3;
const DPAD_UP = 12;
const DPAD_DOWN = 13;

interface GamepadActions {
  onUp?: () => void;
  onDown?: () => void;
  onConfirm?: () => void;
  onBack?: () => void;
  onNew?: () => void;
  onMic?: () => void;
  onConnected?: (connected: boolean) => void;
}

export function useGamepad(actions: GamepadActions) {
  const actionsRef = useRef(actions);
  actionsRef.current = actions;

  useEffect(() => {
    const prevButtons: Record<number, boolean> = {};
    const heldSince: Record<number, number> = {};
    const lastRepeat: Record<number, number> = {};
    let raf: number;

    const REPEAT_BTNS = new Set([DPAD_UP, DPAD_DOWN]);
    const BUTTON_MAP: [number, keyof GamepadActions][] = [
      [BTN_A, "onConfirm"],
      [BTN_B, "onBack"],
      [BTN_X, "onMic"],
      [BTN_Y, "onNew"],
      [DPAD_UP, "onUp"],
      [DPAD_DOWN, "onDown"],
    ];

    function poll() {
      const gamepads = navigator.getGamepads();
      const gp = gamepads[0];
      if (gp) {
        const now = Date.now();
        for (const [idx, actionKey] of BUTTON_MAP) {
          const pressed = gp.buttons[idx]?.pressed ?? false;
          const wasPressed = prevButtons[idx] ?? false;

          if (pressed && !wasPressed) {
            (actionsRef.current[actionKey] as (() => void) | undefined)?.();
            if (REPEAT_BTNS.has(idx)) {
              heldSince[idx] = now;
              lastRepeat[idx] = now;
            }
          } else if (pressed && wasPressed && REPEAT_BTNS.has(idx)) {
            if (now - heldSince[idx] > REPEAT_DELAY && now - lastRepeat[idx] > REPEAT_INTERVAL) {
              (actionsRef.current[actionKey] as (() => void) | undefined)?.();
              lastRepeat[idx] = now;
            }
          } else if (!pressed && wasPressed) {
            delete heldSince[idx];
            delete lastRepeat[idx];
          }
          prevButtons[idx] = pressed;
        }
      }
      raf = requestAnimationFrame(poll);
    }

    function onConnected() { actionsRef.current.onConnected?.(true); }
    function onDisconnected() { actionsRef.current.onConnected?.(false); }

    window.addEventListener("gamepadconnected", onConnected);
    window.addEventListener("gamepaddisconnected", onDisconnected);

    if (navigator.getGamepads().some(Boolean)) {
      actionsRef.current.onConnected?.(true);
    }

    raf = requestAnimationFrame(poll);
    return () => {
      cancelAnimationFrame(raf);
      window.removeEventListener("gamepadconnected", onConnected);
      window.removeEventListener("gamepaddisconnected", onDisconnected);
    };
  }, []);
}