src/impl/conversions.js
import { Util } from './util';
const nonLeapLadder = [0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334],
leapLadder = [0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335];
function dayOfWeek(year, month, day) {
const js = new Date(Date.UTC(year, month - 1, day)).getUTCDay();
return js === 0 ? 7 : js;
}
function lastWeekNumber(weekYear) {
const p1 =
(weekYear +
Math.floor(weekYear / 4) -
Math.floor(weekYear / 100) +
Math.floor(weekYear / 400)) %
7,
last = weekYear - 1,
p2 = (last + Math.floor(last / 4) - Math.floor(last / 100) + Math.floor(last / 400)) % 7;
return p1 === 4 || p2 === 3 ? 53 : 52;
}
function computeOrdinal(year, month, day) {
return day + (Util.isLeapYear(year) ? leapLadder : nonLeapLadder)[month - 1];
}
function uncomputeOrdinal(year, ordinal) {
const table = Util.isLeapYear(year) ? leapLadder : nonLeapLadder,
month0 = table.findIndex(i => i < ordinal),
day = ordinal - table[month0];
return { month: month0 + 1, day };
}
/**
* @private
*/
export class Conversions {
static gregorianToWeek(gregObj) {
const { year, month, day } = gregObj,
ordinal = computeOrdinal(year, month, day),
weekday = dayOfWeek(year, month, day);
let weekNumber = Math.floor((ordinal - weekday + 10) / 7),
weekYear;
if (weekNumber < 1) {
weekYear = year - 1;
weekNumber = lastWeekNumber(weekYear);
} else if (weekNumber > lastWeekNumber(year)) {
weekYear = year + 1;
weekNumber = 1;
} else {
weekYear = year;
}
return Object.assign({ weekYear, weekNumber, weekday }, Util.timeObject(gregObj));
}
static weekToGregorian(weekData) {
const { weekYear, weekNumber, weekday } = weekData,
weekdayOfJan4 = dayOfWeek(weekYear, 1, 4),
daysInYear = Util.daysInYear(weekYear);
let ordinal = weekNumber * 7 + weekday - weekdayOfJan4 - 3,
year;
if (ordinal < 1) {
year = weekYear - 1;
ordinal += Util.daysInYear(year);
} else if (ordinal > daysInYear) {
year = weekYear + 1;
ordinal -= Util.daysInYear(year);
} else {
year = weekYear;
}
const { month, day } = uncomputeOrdinal(year, ordinal);
return Object.assign({ year, month, day }, Util.timeObject(weekData));
}
static gregorianToOrdinal(gregData) {
const { year, month, day } = gregData,
ordinal = computeOrdinal(year, month, day);
return Object.assign({ year, ordinal }, Util.timeObject(gregData));
}
static ordinalToGregorian(ordinalData) {
const { year, ordinal } = ordinalData,
{ month, day } = uncomputeOrdinal(year, ordinal);
return Object.assign({ year, month, day }, Util.timeObject(ordinalData));
}
static hasInvalidWeekData(obj) {
const validYear = Util.isNumber(obj.weekYear),
validWeek = Util.numberBetween(obj.weekNumber, 1, lastWeekNumber(obj.weekYear)),
validWeekday = Util.numberBetween(obj.weekday, 1, 7);
if (!validYear) {
return 'weekYear out of range';
} else if (!validWeek) {
return 'week out of range';
} else if (!validWeekday) {
return 'weekday out of range';
} else return false;
}
static hasInvalidOrdinalData(obj) {
const validYear = Util.isNumber(obj.year),
validOrdinal = Util.numberBetween(obj.ordinal, 1, Util.daysInYear(obj.year));
if (!validYear) {
return 'year out of range';
} else if (!validOrdinal) {
return 'ordinal out of range';
} else return false;
}
static hasInvalidGregorianData(obj) {
const validYear = Util.isNumber(obj.year),
validMonth = Util.numberBetween(obj.month, 1, 12),
validDay = Util.numberBetween(obj.day, 1, Util.daysInMonth(obj.year, obj.month));
if (!validYear) {
return 'year out of range';
} else if (!validMonth) {
return 'month out of range';
} else if (!validDay) {
return 'day out of range';
} else return false;
}
static hasInvalidTimeData(obj) {
const validHour = Util.numberBetween(obj.hour, 0, 23),
validMinute = Util.numberBetween(obj.minute, 0, 59),
validSecond = Util.numberBetween(obj.second, 0, 59),
validMillisecond = Util.numberBetween(obj.millisecond, 0, 999);
if (!validHour) {
return 'hour out of range';
} else if (!validMinute) {
return 'minute out of range';
} else if (!validSecond) {
return 'second out of range';
} else if (!validMillisecond) {
return 'millisecond out of range';
} else return false;
}
}