package com.rookandroidtransmission.transformations

import java.time.LocalDate
import java.time.ZoneId
import java.time.ZoneOffset
import java.time.ZonedDateTime
import java.time.format.DateTimeFormatter

object RookDateTimeUtils {
  private val utc: ZoneId get() = ZoneId.of("UTC")
  private val rookDateTimeZFormatter: DateTimeFormatter get() = DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ssX")
  private val rookDateTimeFormatter: DateTimeFormatter get() = DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss.SSS")
  private val rookDateFormatter: DateTimeFormatter get() = DateTimeFormatter.ISO_LOCAL_DATE

  fun toUTC(date: ZonedDateTime): ZonedDateTime {
    val dateUTC = if (date.offset == ZoneOffset.UTC) {
      date
    } else {
      date.withZoneSameInstant(utc)
    }

    val rookDateString = rookDateTimeFormatter.format(dateUTC).plus("Z")

    return stringToZonedDateTime(rookDateString)
  }

  fun stringToZonedDateTime(string: String): ZonedDateTime {
    val date = ZonedDateTime.parse(string, rookDateTimeZFormatter)

    return if (date.offset == ZoneOffset.UTC) {
      date
    } else {
      date.withZoneSameInstant(utc)
    }
  }

  fun stringToLocalDate(string: String): LocalDate {
    return LocalDate.parse(string, rookDateFormatter)
  }
}