import dayjs from 'dayjs'
import { describe, it, expect } from 'vitest'

import { parseDate } from '../index'

const RESULT_DATE_FORMAT = 'YYYY-MM-DD'

describe('parseDate', () => {
	it('returns a working dayjs instance', () => {
		const date = dayjs().format('DD/MM/YYYY')
		const parsedDate = dayjs().format(RESULT_DATE_FORMAT)

		expect(parseDate(date).format(RESULT_DATE_FORMAT)).toBe(parsedDate)
	})

	it('returns a working dayjs instance with custom date format', () => {
		const DATE_FORMAT = 'DD MM YYYY'

		const date = dayjs().format(DATE_FORMAT)
		const parsedDate = dayjs().format(RESULT_DATE_FORMAT)

		expect(parseDate(date, DATE_FORMAT).format(RESULT_DATE_FORMAT)).toBe(
			parsedDate,
		)
	})

	it('returns a working dayjs instance with a positive timezone offset', () => {
		const date = dayjs().format('DD/MM/YYYY')
		const parsedDate = dayjs().format(RESULT_DATE_FORMAT)

		// Mock getTimezoneOffset
		const originalGetTimezoneOffset = Date.prototype.getTimezoneOffset
		Date.prototype.getTimezoneOffset = () => 160

		expect(parseDate(date).format(RESULT_DATE_FORMAT)).toBe(parsedDate)

		Date.prototype.getTimezoneOffset = originalGetTimezoneOffset
	})

	it('returns a working dayjs instance with a neutral timezone offset', () => {
		const date = dayjs().format('DD/MM/YYYY')
		const parsedDate = dayjs().format(RESULT_DATE_FORMAT)

		// Mock getTimezoneOffset
		const originalGetTimezoneOffset = Date.prototype.getTimezoneOffset
		Date.prototype.getTimezoneOffset = () => 0

		expect(parseDate(date).format(RESULT_DATE_FORMAT)).toBe(parsedDate)

		Date.prototype.getTimezoneOffset = originalGetTimezoneOffset
	})
})