How to use @phensley/timezone - 10 common examples

const index = numarray(raw.index, 36);
    const offsets = numarray(raw.offsets, 36);
    const untils = numarray(raw.untils, 36).map(n => n === -1 ? n : n * 1000);

    for (let i = 0; i < index.length; i += 2) {
      const s = index[i];
      const e = index[i + 1];
      const rec = {
        offsets: offsets.slice(s, e),
        untils: untils.slice(s, e)
      };
      this.metazones.push(rec);
    }

    // mapping of zoneid to metazone records
    const zoneids = TZ.zoneIds();
    const zoneindex = numarray(raw.zoneindex, 36);

    // Mapping of tzdb id back to cldr stable id used for schema lookups
    raw.stableids.split('|').forEach((d: string) => {
      const p = d.split(':');
      const i = Number(p[0]);
      this.stableids.set(zoneids[i], p[1]);
    });

    // Sanity-check, since the zoneindex is based off the canonical
    // zoneids array, but could be generated at different times. our test
    // cases should ensure they're in sync, but warn of a discrepancy
    /* istanbul ignore if */
    if (zoneids.length !== zoneindex.length) {
      console.log(`Error: time zone ids and zone index are not in sync!`);
    }

export const getStableTimeZoneId = (zoneid: string): string => {
  init();
  // Check if this is already a CLDR stable timezone id.
  const isstable = TimeZoneStableIdIndex.get(zoneid) !== -1;
  if (!isstable) {
    // Resolve the passed-in string to a real tzdb zone id
    const realid = TZ.resolveId(zoneid);
    if (realid) {
      // Map to a CLDR stable id
      zoneid = metazones!.getStableId(realid);
    }
  }
  return zoneid;
};

export const zoneInfoFromUTC = (zoneid: string, utc: number): ZoneInfo => {
  init();

  let tzinfo = TZ.fromUTC(zoneid, utc);
  if (tzinfo === undefined) {
    tzinfo = TZ.utcZone();
  }

  // For the purposes of CLDR stable timezone ids, check if the passed-in
  // id is an alias to a current/valid tzdb id.
  const isstable = TimeZoneStableIdIndex.get(zoneid) !== -1;

  // Use the passed-in id as the stable id if it is an alias,
  // otherwise lookup the id in the stable map.
  const stableid = isstable ? zoneid : metazones!.getStableId(tzinfo.zoneid);

  // Use the corrected zone id to lookup the metazone
  const metazoneid = metazones!.getMetazone(tzinfo.zoneid, utc);
  return {
    ...tzinfo,

export const zoneInfoFromUTC = (zoneid: string, utc: number): ZoneInfo => {
  init();

  let tzinfo = TZ.fromUTC(zoneid, utc);
  if (tzinfo === undefined) {
    tzinfo = TZ.utcZone();
  }

  // For the purposes of CLDR stable timezone ids, check if the passed-in
  // id is an alias to a current/valid tzdb id.
  const isstable = TimeZoneStableIdIndex.get(zoneid) !== -1;

  // Use the passed-in id as the stable id if it is an alias,
  // otherwise lookup the id in the stable map.
  const stableid = isstable ? zoneid : metazones!.getStableId(tzinfo.zoneid);

  // Use the corrected zone id to lookup the metazone
  const metazoneid = metazones!.getMetazone(tzinfo.zoneid, utc);
  return {
    ...tzinfo,
    metazoneid: metazoneid || ('' as MetaZoneType),
    stableid

const buildStableIdMapping = (data: any): string => {
  const tzids = TZ.zoneIds();
  const stableids = data.timeZoneIds;
  const res: string[] = [];
  for (const stableid of stableids) {
    const resolved = TZ.resolveId(stableid);
    if (resolved === undefined || stableid === resolved) {
      continue;
    }
    const i = tzids.indexOf(resolved);
    // const j = stableids.indexOf(stableid);
    res.push(`${i}:${stableid}`);
  }
  return res.join('|');
};

Object.keys(data).forEach((id, mi) => {
    // Map the metazone id to the index of the time zone id in the TZ data.
    let zi = zoneids.indexOf(id);
    if (zi === -1) {
      // We have an alias, e.g. Africa/Addis_Ababa, so follow the link to
      // get the correct tzdb id.
      const zid = TZ.resolveId(id);
      if (zid === undefined) {
        throw new Error(`${chalk.red('Error')} tzdb / cldr mismatch. zone id failed ${id}`);
      }
      zi = zoneids.indexOf(zid);
    }

    zonemap.set(zi, mi);
  });

const zones = Object.keys(zoneAlias).filter(alias => {
    const zi = zoneids.indexOf(alias);
    if (zi !== -1) {
      // alias is in list of valid tzdb ids, ignore
      return false;
    }

    // if alias fails to resolve, include in this list
    return TZ.resolveId(alias) === undefined;
  }).sort().map(k => [k, zoneAlias[k]].join(':')).join('|');

const result: Code[] = [];

  let code = HEADER + NOLINT_MAXLINE;
  code += `export const languageAliasRaw = '${languages}';\n\n`;
  code += `export const scriptAliasRaw = '${scripts}';\n`;

  result.push(Code.locale(['autogen.aliases.ts'], code));

  code = HEADER + NOLINT_MAXLINE;
  code += `export const territoryAliasRaw = '${territories}';\n`;

  result.push(Code.languagetag(['autogen.aliases.ts'], code));

  // Find time zone aliases that are not already handled in the @phensley/timezone package
  const zoneids = TZ.zoneIds();
  const zones = Object.keys(zoneAlias).filter(alias => {
    const zi = zoneids.indexOf(alias);
    if (zi !== -1) {
      // alias is in list of valid tzdb ids, ignore
      return false;
    }

    // if alias fails to resolve, include in this list
    return TZ.resolveId(alias) === undefined;
  }).sort().map(k => [k, zoneAlias[k]].join(':')).join('|');

  code = HEADER + NOLINT_MAXLINE;
  code += `export const zoneAliasRaw = '${zones}';\n`;

  result.push(Code.core(['systems', 'calendars', 'autogen.aliases.ts'], code));

const buildStableIdMapping = (data: any): string => {
  const tzids = TZ.zoneIds();
  const stableids = data.timeZoneIds;
  const res: string[] = [];
  for (const stableid of stableids) {
    const resolved = TZ.resolveId(stableid);
    if (resolved === undefined || stableid === resolved) {
      continue;
    }
    const i = tzids.indexOf(resolved);
    // const j = stableids.indexOf(stableid);
    res.push(`${i}:${stableid}`);
  }
  return res.join('|');
};

const buildMetaZones2 = (data: any): Metazones => {
  const metazoneIndex = new IdArray();

  const offsets: number[] = [];
  const untils: number[] = [];
  const index: number[] = [];

  const zonemap = new Map();

  // Array of canonical time zone ids
  const zoneids = TZ.zoneIds();

  Object.keys(data).forEach((id, mi) => {
    // Map the metazone id to the index of the time zone id in the TZ data.
    let zi = zoneids.indexOf(id);
    if (zi === -1) {
      // We have an alias, e.g. Africa/Addis_Ababa, so follow the link to
      // get the correct tzdb id.
      const zid = TZ.resolveId(id);
      if (zid === undefined) {
        throw new Error(`${chalk.red('Error')} tzdb / cldr mismatch. zone id failed ${id}`);
      }
      zi = zoneids.indexOf(zid);
    }

    zonemap.set(zi, mi);
  });