// UTC+8时间处理工具函数

// 固定时间戳（北京时间：2025-12-19 17:10:35.186）
const FIXED_UTC8_TIME = 1766135435186;
let isFixedTimeMode = false; // 默认关闭固定时间模式

/**
 * 获取UTC+8时间戳
 * @param {Date|number} date - 可选，日期对象或时间戳
 * @returns {number} UTC+8时间戳
 */
function getUtc8Timestamp(date) {
  let baseTimestamp;
  if (isFixedTimeMode) {
    baseTimestamp = FIXED_UTC8_TIME;
  } else if (!date) {
    baseTimestamp = Date.now();
  } else if (typeof date === 'number') {
    baseTimestamp = date;
  } else {
    baseTimestamp = date.getTime();
  }
  return baseTimestamp + 8 * 60 * 60 * 1000; // 手动加8小时
}

/**
 * 获取UTC+8 Date对象
 * @param {number} timestamp - 可选，时间戳
 * @returns {Date} UTC+8 Date对象
 */
function getUtc8Date(timestamp) {
  const ts = isFixedTimeMode ? FIXED_UTC8_TIME : (timestamp || Date.now());
  const date = new Date(ts + 8 * 60 * 60 * 1000); // 手动加8小时
  return date;
}

/**
 * 将时间转换为UTC+8的ISO字符串（带时区信息）
 * @param {Date|number} date - 可选，日期对象或时间戳
 * @returns {string} ISO格式的UTC+8时间字符串
 */
function toUtc8ISOString(date) {
  const timestamp = getUtc8Timestamp(date);
  const utcDate = new Date(timestamp);
  
  const year = utcDate.getUTCFullYear();
  const month = String(utcDate.getUTCMonth() + 1).padStart(2, '0');
  const day = String(utcDate.getUTCDate()).padStart(2, '0');
  const hours = String(utcDate.getUTCHours()).padStart(2, '0');
  const minutes = String(utcDate.getUTCMinutes()).padStart(2, '0');
  const seconds = String(utcDate.getUTCSeconds()).padStart(2, '0');
  const milliseconds = String(utcDate.getUTCMilliseconds()).padStart(3, '0');
  
  return `${year}-${month}-${day}T${hours}:${minutes}:${seconds}.${milliseconds}+08:00`;
}

/**
 * 将时间转换为UTC+8的本地字符串
 * @param {Date|number} date - 可选，日期对象或时间戳
 * @param {Object} options - 可选，格式化选项
 * @returns {string} 本地化的UTC+8时间字符串
 */
function toUtc8String(date, options = {}) {
  const defaultOptions = {
    year: 'numeric',
    month: '2-digit',
    day: '2-digit',
    hour: '2-digit',
    minute: '2-digit',
    second: '2-digit',
    hour12: false
    // 移除timeZone设置，因为getUtc8Timestamp已经返回UTC+8时间戳
  };
  
  const timestamp = getUtc8Timestamp(date);
  const utc8Date = new Date(timestamp);
  
  return utc8Date.toLocaleString('zh-CN', { ...defaultOptions, ...options });
}

/**
 * 设置固定时间模式
 * @param {boolean} mode - true启用，false禁用
 */
function setFixedTimeMode(mode) {
  isFixedTimeMode = mode;
}

/**
 * 获取固定时间模式状态
 * @returns {boolean} 当前固定时间模式状态
 */
function getFixedTimeMode() {
  return isFixedTimeMode;
}

// 导出函数
module.exports = {
  getUtc8Timestamp,
  getUtc8Date,
  toUtc8ISOString,
  toUtc8String,
  setFixedTimeMode,
  getFixedTimeMode,
  // 向后兼容别名
  getBeijingTimeTimestamp: getUtc8Timestamp,
  getBeijingTimeDate: getUtc8Date,
  toBeijingTimeISOString: toUtc8ISOString,
  toBeijingTimeString: toUtc8String
};