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import { Timezone } from "./types.ts";
type TokenizeDate = {  year: number;  month: number;  day: number;  hour: number;  minute: number;  second: number;};
export function tzOffset(date: Date, tz: Timezone): number {  const tzDate = tzTokenizeDate(date, tz);
  const { year, month, day, hour, minute, second } = tzDate;  const utc = Date.UTC(year, month - 1, day, hour, minute, second);
  let asTS = date.getTime();  const over = asTS % 1000;  asTS -= over >= 0 ? over : 1000 + over;  return utc - asTS;}
function tzTokenizeDate(date: Date, tz: Timezone) {  const dtf = getDateTimeFormat(tz);  return partsOffset(dtf, date);}
function partsOffset(dtf: Intl.DateTimeFormat, date: Date): TokenizeDate {  const formatted = dtf.formatToParts(date);
  const hash: { [key: string]: number } = {};
  for (const f of formatted) {    hash[f.type] = parseInt(f.value, 10);  }
  return {    year: hash["year"],    month: hash["month"],    day: hash["day"],    hour: hash["hour"],    minute: hash["minute"],    second: hash["second"],  };}
const cache: Map<string, Intl.DateTimeFormat> = new Map();function getDateTimeFormat(tz: Timezone): Intl.DateTimeFormat {  if (!cache.get(tz)) {    const tmpDateFormat = new Intl.DateTimeFormat("en-US", {      hour12: false,      timeZone: "America/New_York",      year: "numeric",      day: "2-digit",      hour: "2-digit",      minute: "2-digit",      second: "2-digit",    }).format(new Date("2021-05-15T04:00:00.123Z"));
    const isHourCycleSupported = tmpDateFormat ===        "05/15/2021, 00:00:00" ||      tmpDateFormat === "‎05‎/15‎/‎2021‎ ‎00‎:‎00‎:‎00";    const format = isHourCycleSupported      ? new Intl.DateTimeFormat("en-US", {        hour12: false,        timeZone: tz,        year: "numeric",        month: "2-digit",        day: "2-digit",        hour: "2-digit",        minute: "2-digit",        second: "2-digit",      })      : new Intl.DateTimeFormat("en-US", {        hourCycle: "h23",        timeZone: tz,        year: "numeric",        month: "2-digit",        day: "2-digit",        hour: "2-digit",        minute: "2-digit",        second: "2-digit",      });    cache.set(tz, format);  }
  return cache.get(tz) as Intl.DateTimeFormat;}