import {
  useMemo, useCallback,
} from 'react'
import { WEEKDAYS } from '../constants.js' // Ensure WEEKDAYS is correctly imported

type HumanReadableOpeningHours = {
  openDay  :string;
  closeDay :string;
  openTime :string;
  closeTime:string;
}

/**
 * Converts a map of human-readable opening hours into a two-tuple representing
 * the start and end times in "hours:minutes" format from the start of the week.
 *
 * @param {HumanReadableOpeningHours} openingHours - The human-readable opening hours.
 * @returns {[string, string]} A two-tuple of start and end times.
 */
const useOpeningHoursToTuple = (openingHours: HumanReadableOpeningHours): [string, string] => {
  const convertDayAndTimeToMinutes = useCallback(
    (
      day: string, time: string,
    ): number => {
      const dayIndex = Object.values(WEEKDAYS).findIndex((e) => e === day.toUpperCase())
      const [
        hours,
        minutes,
      ] = time.split(':').map(Number)
      return dayIndex * 24 * 60 + hours * 60 + minutes
    },
    [],
  )

  const formatMinutesToTimeString = useCallback(
    (totalMinutes: number): string => {
      const hours = Math.floor(totalMinutes / 60)
      const minutes = totalMinutes % 60
      return `${hours.toString().padStart(
        2, '0',
      )}:${minutes
        .toString()
        .padStart(
          2, '0',
        )}`
    },
    [],
  )

  const isReady = useMemo(
    () => [
      openingHours.openDay,
      openingHours.closeDay,
      openingHours.openTime,
      openingHours.closeTime,
    ].every(Boolean),
    [openingHours],
  )

  return useMemo(
    () => {
      if (!isReady) {
        return null
      }
      const startMinutes = convertDayAndTimeToMinutes(
        openingHours.openDay,
        openingHours.openTime,
      )

      const endMinutes = convertDayAndTimeToMinutes(
        openingHours.closeDay,
        openingHours.closeTime,
      )

      const startTime = formatMinutesToTimeString(startMinutes)
      const endTime = formatMinutesToTimeString(endMinutes)

      return [
        startTime,
        endTime,
      ]
    }, [
      openingHours,
      convertDayAndTimeToMinutes,
      formatMinutesToTimeString,
    ],
  )
}

export default useOpeningHoursToTuple