react-day-picker/src/utils/dateMatchModifiers.ts

Customizable Date Picker for React

import type { DateLib, Matcher } from "../types/index.js";

import { rangeIncludesDate } from "./rangeIncludesDate.js";
import {
  isDateAfterType,
  isDateBeforeType,
  isDateInterval,
  isDateRange,
  isDatesArray,
  isDayOfWeekType
} from "./typeguards.js";

/**
 * Returns whether a day matches against at least one of the given
 * {@link Matcher}.
 *
 * ```tsx
 * const day = new Date(2022, 5, 19);
 * const matcher1: DateRange = {
 *  from: new Date(2021, 12, 21),
 *  to: new Date(2021, 12, 30)
 * }
 * const matcher2: DateRange = {
 *  from: new Date(2022, 5, 1),
 *  to: new Date(2022, 5, 23)
 * }
 * const isMatch(day, [matcher1, matcher2]); // true, since day is in the matcher1 range.
 * ```
 *
 * @group Utilities
 */
export function dateMatchModifiers(
  date: Date,
  matchers: Matcher | Matcher[],
  dateLib: DateLib
): boolean {
  const matchersArr = !Array.isArray(matchers) ? [matchers] : matchers;
  const { isSameDay, differenceInCalendarDays, isAfter } = dateLib;
  return matchersArr.some((matcher: Matcher) => {
    if (typeof matcher === "boolean") {
      return matcher;
    }
    if (dateLib.isDate(matcher)) {
      return isSameDay(date, matcher);
    }
    if (isDatesArray(matcher, dateLib)) {
      return matcher.includes(date);
    }
    if (isDateRange(matcher)) {
      return rangeIncludesDate(matcher, date, false, dateLib);
    }
    if (isDayOfWeekType(matcher)) {
      if (!Array.isArray(matcher.dayOfWeek)) {
        return matcher.dayOfWeek === date.getDay();
      }
      return matcher.dayOfWeek.includes(date.getDay());
    }
    if (isDateInterval(matcher)) {
      const diffBefore = differenceInCalendarDays(matcher.before, date);
      const diffAfter = differenceInCalendarDays(matcher.after, date);
      const isDayBefore = diffBefore > 0;
      const isDayAfter = diffAfter < 0;
      const isClosedInterval = isAfter(matcher.before, matcher.after);
      if (isClosedInterval) {
        return isDayAfter && isDayBefore;
      } else {
        return isDayBefore || isDayAfter;
      }
    }
    if (isDateAfterType(matcher)) {
      return differenceInCalendarDays(date, matcher.after) > 0;
    }
    if (isDateBeforeType(matcher)) {
      return differenceInCalendarDays(matcher.before, date) > 0;
    }
    if (typeof matcher === "function") {
      return matcher(date);
    }
    return false;
  });
}