"use strict";
const units = require("./units.js");
const { YEAR, MONTH, DATE, HOUR, MINUTE, SECOND, MILLISECOND, UTC_OFFSET } = units;
function escapeRegex(str) {
  return str.replace(/[.*+?^${}()|[\]\\]/g, "\\$&");
}
const TOKEN_MAP = {
  YYYY: { pattern: "(\\d{1,4})", key: YEAR },
  // 年份
  // YY: { pattern: '(\\d{1,2})', key: YEAR }, // 年份
  MM: { pattern: "(\\d{1,2})", key: MONTH },
  // 月份
  DD: { pattern: "(\\d{1,2})", key: DATE },
  // 日期
  HH: { pattern: "(\\d{1,2})", key: HOUR },
  // 小时
  mm: { pattern: "(\\d{1,2})", key: MINUTE },
  // 分钟
  ss: { pattern: "(\\d{1,2})", key: SECOND },
  // 秒
  SSS: { pattern: "(\\d{1,3})", key: MILLISECOND },
  // 毫秒
  Z: { pattern: "(Z|[+-]\\d{2}(?::?\\d{2})?)", key: UTC_OFFSET }
  // 时区
};
const TOKEN_KEYS = Object.keys(TOKEN_MAP).sort((a, b) => b.length - a.length);
const TOKEN_PATTERN = new RegExp(`(${TOKEN_KEYS.join("|")})`, "g");
function compile(formatString) {
  const matchedTokens = [];
  const pattern = escapeRegex(formatString).replace(TOKEN_PATTERN, (m) => {
    matchedTokens.push(m);
    return TOKEN_MAP[m].pattern;
  });
  return { pattern, tokens: matchedTokens };
}
module.exports = compile;