import readline from "readline";

let initialized = false;
let currentHandler = null;

function ensureRawMode(enabled) {
  if (process.stdin.isTTY) {
    process.stdin.setRawMode(enabled);
  }
}

export function initKeypress() {
  // 清理所有keypress监听器
  process.stdin.removeAllListeners("keypress");
  currentHandler = null;

  // 确保raw mode关闭再重新开启
  ensureRawMode(false);

  // 初始化readline（只需一次）
  if (!initialized) {
    readline.emitKeypressEvents(process.stdin);
    initialized = true;
  }

  // 短暂延迟后再开启raw mode
  setImmediate(() => {
    ensureRawMode(true);
  });
}

export function onKey(handler) {
  // 清理旧的监听器
  process.stdin.removeAllListeners("keypress");
  currentHandler = handler;
  process.stdin.on("keypress", handler);
}

export function stopKeypress() {
  process.stdin.removeAllListeners("keypress");
  currentHandler = null;
  ensureRawMode(false);
}

export function waitForKey(message = "按任意键返回...", predicate = () => true) {
  return new Promise(resolve => {
    console.log("\n" + message);
    initKeypress();
    onKey((str, key) => {
      const pressed = key || {};
      if (!predicate(pressed)) return;
      stopKeypress();
      resolve(pressed);
    });
  });
}