import { TimetableEntry } from '@skolplattformen/api'
import parse, { Language } from '@skolplattformen/curriculum'
import { DateTime } from 'luxon'

const calculateDate = (
  year: number,
  weekNumber: number,
  weekday: number,
  time: string
): string => {
  const [hours, minutes, seconds] = time.split(':')
  return DateTime.local()
    .set({
      weekYear: year,
      weekNumber,
      weekday,
      hour: parseInt(hours, 10),
      minute: parseInt(minutes, 10),
      second: parseInt(seconds, 10),
      millisecond: 0,
    })
    .toISO()
}

interface TimetableResponseEntry {
  guidId: string
  texts: string[]
  timeStart: string
  timeEnd: string
  dayOfWeekNumber: number
  blockName: string
}
export interface TimetableResponse {
  error: string | null
  data: {
    textList: any[]
    boxList: any[]
    lineList: any[]
    lessonInfo: TimetableResponseEntry[]
  }
  exception: any
  validation: any[]
}

interface EntryParser {
  (
    args: TimetableResponseEntry,
    year: number,
    week: number,
    lang: Language
  ): TimetableEntry
}
export const timetableEntry: EntryParser = (
  {
    guidId,
    texts: [code, teacher, location],
    timeStart,
    timeEnd,
    dayOfWeekNumber,
    blockName,
  },
  year,
  week,
  lang
) => ({
  ...parse(code, lang),
  id: guidId,
  blockName,
  dayOfWeek: dayOfWeekNumber,
  location,
  teacher,
  timeEnd,
  timeStart,
  dateStart: calculateDate(year, week, dayOfWeekNumber, timeStart),
  dateEnd: calculateDate(year, week, dayOfWeekNumber, timeEnd),
})

export const timetable = (
  response: TimetableResponse,
  year: number,
  week: number,
  lang: Language
) => {
  if (response.error) {
    throw new Error(response.error)
  }

  if (!response.data.lessonInfo) {
    throw new Error('Empty lessonInfo received')
  }

  return response.data.lessonInfo.map((entry) =>
    timetableEntry(entry, year, week, lang)
  )
}