/* 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 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ "use strict"; /** * DateKeeper keeps track of the date states. */ function DateKeeper(props) { this.init(props); } { const DAYS_IN_A_WEEK = 7, MONTHS_IN_A_YEAR = 12, YEAR_VIEW_SIZE = 200, YEAR_BUFFER_SIZE = 10, // The min and max values are derived from the ECMAScript spec: // http://ecma-international.org/ecma-262/5.1/#sec-15.9.1.1 MIN_DATE = -8640000000000000, MAX_DATE = 8640000000000000; DateKeeper.prototype = { get year() { return this.state.dateObj.getUTCFullYear(); }, get month() { return this.state.dateObj.getUTCMonth(); }, get day() { return this.state.dateObj.getUTCDate(); }, get selection() { return this.state.selection; }, /** * Initialize DateKeeper * @param {Number} year * @param {Number} month * @param {Number} day * @param {String} min * @param {String} max * @param {Number} firstDayOfWeek * @param {Array} weekends * @param {Number} calViewSize */ init({ year, month, day, min, max, firstDayOfWeek = 0, weekends = [0], calViewSize = 42 }) { const today = new Date(); const isDateSet = year != undefined && month != undefined && day != undefined; this.state = { firstDayOfWeek, weekends, calViewSize, min: new Date(min != undefined ? min : MIN_DATE), max: new Date(max != undefined ? max : MAX_DATE), today: this._newUTCDate(today.getFullYear(), today.getMonth(), today.getDate()), weekHeaders: this._getWeekHeaders(firstDayOfWeek, weekends), years: [], months: [], days: [], selection: { year, month, day }, }; this.state.dateObj = isDateSet ? this._newUTCDate(year, month, day) : new Date(this.state.today); }, /** * Set new date. The year is always treated as full year, so the short-form * is not supported. * @param {Object} date parts * { * {Number} year [optional] * {Number} month [optional] * {Number} date [optional] * } */ set({ year = this.year, month = this.month, day = this.day }) { // Use setUTCFullYear so that year 99 doesn't get parsed as 1999 this.state.dateObj.setUTCFullYear(year, month, day); }, /** * Set selection date * @param {Number} year * @param {Number} month * @param {Number} day */ setSelection({ year, month, day }) { this.state.selection.year = year; this.state.selection.month = month; this.state.selection.day = day; }, /** * Set month. Makes sure the day is <= the last day of the month * @param {Number} month */ setMonth(month) { const lastDayOfMonth = this._newUTCDate(this.year, month + 1, 0).getUTCDate(); this.set({ year: this.year, month, day: Math.min(this.day, lastDayOfMonth) }); }, /** * Set year. Makes sure the day is <= the last day of the month * @param {Number} year */ setYear(year) { const lastDayOfMonth = this._newUTCDate(year, this.month + 1, 0).getUTCDate(); this.set({ year, month: this.month, day: Math.min(this.day, lastDayOfMonth) }); }, /** * Set month by offset. Makes sure the day is <= the last day of the month * @param {Number} offset */ setMonthByOffset(offset) { const lastDayOfMonth = this._newUTCDate(this.year, this.month + offset + 1, 0).getUTCDate(); this.set({ year: this.year, month: this.month + offset, day: Math.min(this.day, lastDayOfMonth) }); }, /** * Generate the array of months * @return {Array} * { * {Number} value: Month in int * {Boolean} enabled * } */ getMonths() { let months = []; for (let i = 0; i < MONTHS_IN_A_YEAR; i++) { months.push({ value: i, enabled: true }); } return months; }, /** * Generate the array of years * @return {Array} * { * {Number} value: Year in int * {Boolean} enabled * } */ getYears() { let years = []; const firstItem = this.state.years[0]; const lastItem = this.state.years[this.state.years.length - 1]; const currentYear = this.year; // Generate new years array when the year is outside of the first & // last item range. If not, return the cached result. if (!firstItem || !lastItem || currentYear <= firstItem.value + YEAR_BUFFER_SIZE || currentYear >= lastItem.value - YEAR_BUFFER_SIZE) { // The year is set in the middle with items on both directions for (let i = -(YEAR_VIEW_SIZE / 2); i < YEAR_VIEW_SIZE / 2; i++) { years.push({ value: currentYear + i, enabled: true }); } this.state.years = years; } return this.state.years; }, /** * Get days for calendar * @return {Array} * { * {Date} dateObj * {Array} classNames * {Boolean} enabled * } */ getDays() { // TODO: add step support const firstDayOfMonth = this._getFirstCalendarDate(this.state.dateObj, this.state.firstDayOfWeek); const month = this.month; let days = []; for (let i = 0; i < this.state.calViewSize; i++) { const dateObj = this._newUTCDate(firstDayOfMonth.getUTCFullYear(), firstDayOfMonth.getUTCMonth(), firstDayOfMonth.getUTCDate() + i); let classNames = []; let enabled = true; if (this.state.weekends.includes(dateObj.getUTCDay())) { classNames.push("weekend"); } if (month != dateObj.getUTCMonth()) { classNames.push("outside"); } if (this.state.selection.year == dateObj.getUTCFullYear() && this.state.selection.month == dateObj.getUTCMonth() && this.state.selection.day == dateObj.getUTCDate()) { classNames.push("selection"); } if (dateObj.getTime() < this.state.min.getTime() || dateObj.getTime() > this.state.max.getTime()) { classNames.push("out-of-range"); enabled = false; } if (this.state.today.getTime() == dateObj.getTime()) { classNames.push("today"); } days.push({ dateObj, classNames, enabled, }); } return days; }, /** * Get week headers for calendar * @param {Number} firstDayOfWeek * @param {Array} weekends * @return {Array} * { * {Number} textContent * {Array} classNames * } */ _getWeekHeaders(firstDayOfWeek, weekends) { let headers = []; let dayOfWeek = firstDayOfWeek; for (let i = 0; i < DAYS_IN_A_WEEK; i++) { headers.push({ textContent: dayOfWeek % DAYS_IN_A_WEEK, classNames: weekends.includes(dayOfWeek % DAYS_IN_A_WEEK) ? ["weekend"] : [] }); dayOfWeek++; } return headers; }, /** * Get the first day on a calendar month * @param {Date} dateObj * @param {Number} firstDayOfWeek * @return {Date} */ _getFirstCalendarDate(dateObj, firstDayOfWeek) { const daysOffset = 1 - DAYS_IN_A_WEEK; let firstDayOfMonth = this._newUTCDate(dateObj.getUTCFullYear(), dateObj.getUTCMonth()); let dayOfWeek = firstDayOfMonth.getUTCDay(); return this._newUTCDate( firstDayOfMonth.getUTCFullYear(), firstDayOfMonth.getUTCMonth(), // When first calendar date is the same as first day of the week, add // another row on top of it. firstDayOfWeek == dayOfWeek ? daysOffset : (firstDayOfWeek - dayOfWeek + daysOffset) % DAYS_IN_A_WEEK); }, /** * Helper function for creating UTC dates * @param {...[Number]} parts * @return {Date} */ _newUTCDate(...parts) { return new Date(Date.UTC(...parts)); } }; }