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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
const TIMEZONES = {
IDLW: -12,
NT: -11,
HST: -10,
AKST: -9,
PST: -8,
AKDT: -8,
MST: -7,
PDT: -7,
CST: -6,
MDT: -6,
EST: -5,
CDT: -5,
EDT: -4,
AST: -4,
GUY: -3,
ADT: -3,
AT: -2,
UTC: 0,
GMT: 0,
Z: 0,
WET: 0,
WEST: 1,
CET: 1,
BST: 1,
IST: 1,
CEST: 2,
EET: 2,
EEST: 3,
MSK: 3,
MSD: 4,
ZP4: 4,
ZP5: 5,
ZP6: 6,
WAST: 7,
AWST: 8,
WST: 8,
JST: 9,
ACST: 9.5,
ACDT: 10.5,
AEST: 10,
AEDT: 11,
NZST: 12,
IDLE: 12,
NZD: 13,
};
const TIME_REGEX = "([0-2]?[0-9])(:([0-5][0-9]))?\\s*([ap]m)?";
const TIMEZONE_REGEX = "\\w+";
// NOTE: This regex need to be localized upon supporting multi locales
// since it supports en-US input format only.
const QUERY_REGEX = new RegExp(
`^(${TIME_REGEX}|now)\\s*(${TIMEZONE_REGEX})?(?:\\s+in\\s+|\\s+to\\s+|\\s*=\\s*)(${TIMEZONE_REGEX}|here)`,
"i"
);
const KEYWORD_HERE = "HERE";
const KEYWORD_NOW = "NOW";
/**
* This module converts timezone.
*/
export class UnitConverterTimezone {
/**
* Convert the given search string.
*
* @param {string} searchString
* The string to be converted
* @returns {string} conversion result.
*/
convert(searchString) {
const regexResult = QUERY_REGEX.exec(searchString);
if (!regexResult) {
return null;
}
const inputTime = regexResult[1].toUpperCase();
const inputTimezone = regexResult[6]?.toUpperCase();
let outputTimezone = regexResult[7].toUpperCase();
if (
(inputTimezone &&
inputTimezone !== KEYWORD_NOW &&
!(inputTimezone in TIMEZONES)) ||
(outputTimezone !== KEYWORD_HERE && !(outputTimezone in TIMEZONES))
) {
return null;
}
const inputDate = new Date();
let isMeridiemNeeded = false;
if (inputTime === KEYWORD_NOW) {
inputDate.setUTCHours(inputDate.getHours());
inputDate.setUTCMinutes(inputDate.getMinutes());
} else {
// If the input was given as AM/PM, we need to convert it to 24h.
// 12AM is converted to 00, and for PM times we add 12 to the hour value except for 12PM.
// If the input is for example 23PM, we use 23 as the hour - we don't add 12 as this would result in a date increment.
const inputAMPM = regexResult[5]?.toLowerCase() || "";
const inputHours =
regexResult[2] === "12" && inputAMPM === "am"
? 0
: Number(regexResult[2]);
const inputMinutes = regexResult[4] ? Number(regexResult[4]) : 0;
const inputMeridianHourShift =
inputAMPM === "pm" && inputHours < 12 ? 12 : 0;
inputDate.setUTCHours(inputHours + inputMeridianHourShift);
inputDate.setUTCMinutes(inputMinutes);
isMeridiemNeeded = !!inputAMPM;
}
const inputOffset = inputTimezone
? TIMEZONES[inputTimezone] * 60
: -inputDate.getTimezoneOffset();
let outputOffset;
if (outputTimezone === KEYWORD_HERE) {
outputOffset = -inputDate.getTimezoneOffset();
const sign = -inputDate.getTimezoneOffset() > 0 ? "+" : "-";
const hours = parseInt(Math.abs(outputOffset) / 60);
const minutes = formatMinutes((outputOffset % 60) * 60);
outputTimezone = `UTC${sign}${hours}${minutes}`;
} else {
outputOffset = TIMEZONES[outputTimezone] * 60;
}
const outputDate = new Date(inputDate.getTime());
outputDate.setUTCMinutes(
outputDate.getUTCMinutes() - inputOffset + outputOffset
);
const time = new Intl.DateTimeFormat("en-US", {
timeStyle: "short",
hour12: isMeridiemNeeded,
timeZone: "UTC",
}).format(outputDate);
return `${time} ${outputTimezone}`;
}
}
function formatMinutes(minutes) {
return minutes.toString().padStart(2, "0");
}