date-fns-adapter.ts

/* tslint:disable */

import { CptDateAdapter } from './date-adapter';

import {
  getYear,
  getMonth,
  getDate,
  getDay,
  getDaysInMonth,
  parse as dateFnsParse,
  addYears,
  addMonths,
  addDays,
  isSameMinute,
  isValid,
  setHours,
  setMinutes,
  getHours,
  getMinutes
} from 'date-fns/esm';

// TODO(mmalerba): Remove when we no longer support safari 9.
/** Whether the browser supports the Intl API. */
const SUPPORTS_INTL_API = typeof Intl != 'undefined';


/** The default month names to use if Intl API is not available. */
const DEFAULT_MONTH_NAMES = {
  'long': [
    'January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September',
    'October', 'November', 'December'
  ],
  'short': ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'],
  'narrow': ['J', 'F', 'M', 'A', 'M', 'J', 'J', 'A', 'S', 'O', 'N', 'D']
};


/** The default date names to use if Intl API is not available. */
const DEFAULT_DATE_NAMES = range(31, i => String(i + 1));


/** The default day of the week names to use if Intl API is not available. */
const DEFAULT_DAY_OF_WEEK_NAMES = {
  'long': ['Sunday', 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday'],
  'short': ['Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat'],
  'narrow': ['S', 'M', 'T', 'W', 'T', 'F', 'S']
};


/** Creates an array and fills it with values. */
function range<T>(length: number, valueFunction: (index: number) => T): T[] {
  return Array.apply(null, Array(length)).map((_: undefined, i: number) => valueFunction(i));
}

export class DateFnsDateAdapter extends CptDateAdapter<Date> {
  getYear(date: Date): number {
    return getYear(date);
  }

  getMonth(date: Date): number {
    return getMonth(date);
  }

  getDate(date: Date): number {
    return getDate(date);
  }

  getDayOfWeek(date: Date): number {
    return getDay(date);
  }

  getMonthNames(style: 'long' | 'short' | 'narrow'): string[] {
    if (SUPPORTS_INTL_API) {
      let dtf = new Intl.DateTimeFormat(this.locale, {month: style});
      return range(12, i => dtf.format(new Date(2017, i, 1)));
    }
    return DEFAULT_MONTH_NAMES[style];
  }

  getDateNames(): string[] {
    if (SUPPORTS_INTL_API) {
      let dtf = new Intl.DateTimeFormat(this.locale, {day: 'numeric'});
      return range(31, i => dtf.format(new Date(2017, 0, i + 1)));
    }
    return DEFAULT_DATE_NAMES;
  }

  getDayOfWeekNames(style: 'long' | 'short' | 'narrow'): string[] {
    if (SUPPORTS_INTL_API) {
      let dtf = new Intl.DateTimeFormat(this.locale, {weekday: style});
      return range(7, i => dtf.format(new Date(2017, 0, i + 1)));
    }
    return DEFAULT_DAY_OF_WEEK_NAMES[style];
  }

  getYearName(date: Date): string {
    if (SUPPORTS_INTL_API) {
      let dtf = new Intl.DateTimeFormat(this.locale, {year: 'numeric'});
      return dtf.format(date);
    }
    return String(this.getYear(date));
  }

  getFirstDayOfWeek(): number {
    // We can't tell using native JS Date what the first day of the week is, we default to Sunday.
    return 0;
  }

  getNumDaysInMonth(date: Date): number {
    return getDaysInMonth(date);
  }

  clone(date: Date): Date {
    return this.createDate(this.getYear(date), this.getMonth(date), this.getDate(date));
  }

  createDate(year: number, month: number, date: number): Date {
    return this.parse(new Date(year, month, date));
  }

  today(): Date {
    return new Date();
  }

  parse(value: any, parseFormat?: string): Date | null {
    if (value instanceof Date) {
      return value;
    }

    const parsedDate = dateFnsParse(value, parseFormat, new Date());
    const r = value && isValid(parsedDate) ? parsedDate : null;
    return r;
  }

  format(date: Date, displayFormat: Object): string {
    if (SUPPORTS_INTL_API) {
      let dtf = new Intl.DateTimeFormat(this.locale, displayFormat);
      return dtf.format(date);
    }

    return date.toDateString();
  }

  addCalendarYears(date: Date, years: number): Date {
    return addYears(date, years);
  }

  addCalendarMonths(date: Date, months: number): Date {
    return addMonths(date, months);
  }

  addCalendarDays(date: Date, days: number): Date {
    return addDays(date, days);
  }

  getISODateString(date: Date): string {
    return [
      date.getUTCFullYear(),
      this._2digit(date.getUTCMonth() + 1),
      this._2digit(date.getUTCDate())
    ].join('-');
  }

  /**
   * Pads a number to make it two digits.
   * @param n The number to pad.
   * @returns The padded number.
   */
  private _2digit(n: number) {
    return ('00' + n).slice(-2);
  }

  getHour(date: Date): number {
    return getHours(date);
  }

  getMinute(date: Date): number {
    return getMinutes(date);
  }

  setHour(date: Date, hour: number): Date {
    return setHours(date, hour);
  }

  setMinute(date: Date, minute: number): Date {
    return setMinutes(date, minute);
  }

  sameTime(first: Date | null, second: Date | null): boolean {
    return isSameMinute(first, second);
  }

}