zappyzep/backend/src/utils/parseFuzzyTimezone.ts

32 lines
1.1 KiB
TypeScript

import moment from "moment-timezone";
import escapeStringRegexp from "escape-string-regexp";
const normalizeTzName = str => str.replace(/[^a-zA-Z0-9+\-]/g, "").toLowerCase();
const validTimezones = moment.tz.names();
const normalizedTimezoneMap = validTimezones.reduce((map, tz) => {
map.set(normalizeTzName(tz), tz);
return map;
}, new Map());
const normalizedTimezones = Array.from(normalizedTimezoneMap.keys());
export function parseFuzzyTimezone(input: string) {
const normalizedInput = normalizeTzName(input);
if (normalizedTimezoneMap.has(normalizedInput)) {
return normalizedTimezoneMap.get(normalizedInput);
}
const searchRegex = new RegExp(`.*${escapeStringRegexp(normalizedInput)}.*`);
for (const tz of normalizedTimezones) {
if (searchRegex.test(tz)) {
const result = normalizedTimezoneMap.get(tz);
// Ignore Etc/GMT timezones unless explicitly specified, as they have confusing functionality
// with the inverted +/- sign
if (result.startsWith("Etc/GMT")) continue;
return result;
}
}
return null;
}