tsms/src/app/utils/holidayUtils.ts

import Holidays from "date-holidays";
import { HolidaysResult } from "../api/holidays";
import dayjs from "dayjs";
import arraySupport from "dayjs/plugin/arraySupport";
import { INPUT_DATE_FORMAT } from "./formatUtil";

dayjs.extend(arraySupport);

const hd = new Holidays("HK");

export const getPublicHolidaysForNYears = (years: number = 1, currYr?: number) => {
  return Array(years)
    .fill(undefined)
    .flatMap((_, index) => {
      const currentYear = currYr ?? new Date().getFullYear();
      const holidays = hd.getHolidays(currentYear + index);
      return holidays.map((ele) => {
        const tempDay = new Date(ele.date);
        const tempYear = tempDay.getFullYear();
        const tempMonth =
          tempDay.getMonth() + 1 < 10
            ? `0${tempDay.getMonth() + 1}`
            : tempDay.getMonth() + 1;
        const tempDate =
          tempDay.getDate() < 10 ? `0${tempDay.getDate()}` : tempDay.getDate();
        let tempName = "";
        switch (ele.name) {
          case "复活节":
            tempName = "復活節";
            break;
          case "劳动节":
            tempName = "勞動節";
            break;
          case "端午节":
            tempName = "端午節";
            break;
          case "重阳节":
            tempName = "重陽節";
            break;
          case "圣诞节后的第一个工作日":
            tempName = "聖誕節後的第一个工作日";
            break;
          default:
            tempName = ele.name;
            break;
        }

        return {
          date: `${tempYear}-${tempMonth}-${tempDate}`,
          title: tempName,
          extendedProps: { calendar: "holiday" },
        };
      });
    });
};

export const getHolidayForDate = (
  date: string,
  companyHolidays: HolidaysResult[] = [],
) => {
  const currentYearHolidays: { date: string; title: string }[] = companyHolidays
    .map((h) => ({
      title: h.name,
      // Dayjs use 0-index for months, but not our API
      date: dayjs([h.date[0], h.date[1] - 1, h.date[2]]).format(
        INPUT_DATE_FORMAT,
      ),
    }))
    .concat(getPublicHolidaysForNYears(1).concat());

  return currentYearHolidays.find((h) => h.date === date);
};