import toDate from '../toDate/index'
import type { AreIntervalsOverlappingOptions, Interval } from '../types'
import requiredArgs from '../_lib/requiredArgs/index'

/**
 * @name areIntervalsOverlapping
 * @category Interval Helpers
 * @summary Is the given time interval overlapping with another time interval?
 *
 * @description
 * Is the given time interval overlapping with another time interval? Adjacent intervals do not count as overlapping.
 *
 * @param {Interval} intervalLeft - the first interval to compare. See [Interval]{@link https://date-fns.org/docs/Interval}
 * @param {Interval} intervalRight - the second interval to compare. See [Interval]{@link https://date-fns.org/docs/Interval}
 * @param {Object} [options] - the object with options
 * @param {Boolean} [options.inclusive=false] - whether the comparison is inclusive or not
 * @returns {Boolean} whether the time intervals are overlapping
 * @throws {TypeError} 2 arguments required
 * @throws {RangeError} The start of an interval cannot be after its end
 * @throws {RangeError} Date in interval cannot be `Invalid Date`
 *
 * @example
 * // For overlapping time intervals:
 * areIntervalsOverlapping(
 *   { start: new Date(2014, 0, 10), end: new Date(2014, 0, 20) },
 *   { start: new Date(2014, 0, 17), end: new Date(2014, 0, 21) }
 * )
 * //=> true
 *
 * @example
 * // For non-overlapping time intervals:
 * areIntervalsOverlapping(
 *   { start: new Date(2014, 0, 10), end: new Date(2014, 0, 20) },
 *   { start: new Date(2014, 0, 21), end: new Date(2014, 0, 22) }
 * )
 * //=> false
 *
 * @example
 * // For adjacent time intervals:
 * areIntervalsOverlapping(
 *   { start: new Date(2014, 0, 10), end: new Date(2014, 0, 20) },
 *   { start: new Date(2014, 0, 20), end: new Date(2014, 0, 30) }
 * )
 * //=> false
 *
 * @example
 * // Using the inclusive option:
 * areIntervalsOverlapping(
 *   { start: new Date(2014, 0, 10), end: new Date(2014, 0, 20) },
 *   { start: new Date(2014, 0, 20), end: new Date(2014, 0, 24) }
 * )
 * //=> false
 * areIntervalsOverlapping(
 *   { start: new Date(2014, 0, 10), end: new Date(2014, 0, 20) },
 *   { start: new Date(2014, 0, 20), end: new Date(2014, 0, 24) },
 *   { inclusive: true }
 * )
 * //=> true
 */
export default function areIntervalsOverlapping(
  intervalLeft: Interval,
  intervalRight: Interval,
  options?: AreIntervalsOverlappingOptions
): boolean {
  requiredArgs(2, arguments)

  const leftStartTime = toDate(intervalLeft?.start).getTime()
  const leftEndTime = toDate(intervalLeft?.end).getTime()
  const rightStartTime = toDate(intervalRight?.start).getTime()
  const rightEndTime = toDate(intervalRight?.end).getTime()

  // Throw an exception if start date is after end date or if any date is `Invalid Date`
  if (!(leftStartTime <= leftEndTime && rightStartTime <= rightEndTime)) {
    throw new RangeError('Invalid interval')
  }

  if (options?.inclusive) {
    return leftStartTime <= rightEndTime && rightStartTime <= leftEndTime
  }

  return leftStartTime < rightEndTime && rightStartTime < leftEndTime
}