// SPDX-License-Identifier: MIT
// Copyright (C) 2022 Roland Csaszar
//
// Project:  purescript-datetimeformat
// File:     DateTimeFormat.js
// Date:     12.Feb.2022
//
// ==============================================================================
/* eslint-disable max-params */
/* eslint-disable no-undef */
/* eslint-disable no-undefined */
/* eslint-disable max-lines-per-function */
/* eslint-disable max-statements */
/* eslint-disable complexity */

// eslint-disable-next-line strict
"use strict"

exports.defaultDateTimeFormat = defaultDateTimeFormat
exports.isoDateTimeNow = isoDateTimeNow
exports.isoDateTimeJS = isoDateTimeJS
exports.formatDateTimeNow = formatDateTimeNow
exports.formatDateJS = formatDateJS
exports.formatDateTimeJS = formatDateTimeJS
exports.getDateTimeFormatJS = getDateTimeFormatJS

/**
 * Return the default `DateTimeFormat` object of the current locale.
 *
 * @returns The default `DateTimeFormat` object of the current locale.
 */
function defaultDateTimeFormat() {
    return function () {
        return new Intl.DateTimeFormat()
    }
}

/**
 * Return the formatter with the given locale and options.
 *
 * @param {string[]} locales - The array of locales.
 * @param {DateTimeFormatOptionsJS} options - The options of
 *                                            `Intl.DateTimeFormat`
 * @returns The formatter with the given options and locale.
 */

function getDateTimeFormatJS(
    locales,
    {
        dateStyle,
        timeStyle,
        calendar,
        dayPeriod,
        numberingSystem,
        localeMatcher,
        timeZone,
        hour12,
        hourCycle,
        formatMatcher,
        weekDay,
        era,
        year,
        month,
        day,
        hour,
        minute,
        second,
        fractionalSecondDigits,
        timeZoneNameStyle,
    }
) {
    let options = {}
    if (dateStyle !== undefined) {
        const optionsAdd = { dateStyle }
        options = Object.assign(options, optionsAdd)
    }
    if (timeStyle !== undefined) {
        const optionsAdd = { timeStyle }
        options = Object.assign(options, optionsAdd)
    }
    if (calendar !== undefined) {
        const optionsAdd = { calendar }
        options = Object.assign(options, optionsAdd)
    }
    if (dayPeriod !== undefined) {
        const optionsAdd = { dayPeriod }
        options = Object.assign(options, optionsAdd)
    }
    if (numberingSystem !== undefined) {
        const optionsAdd = { numberingSystem }
        options = Object.assign(options, optionsAdd)
    }
    if (localeMatcher !== undefined) {
        const optionsAdd = { localeMatcher }
        options = Object.assign(options, optionsAdd)
    }
    if (timeZone !== undefined) {
        const optionsAdd = { timeZone }
        options = Object.assign(options, optionsAdd)
    }
    if (hour12 !== undefined) {
        const optionsAdd = { hour12 }
        options = Object.assign(options, optionsAdd)
    }
    if (hourCycle !== undefined) {
        const optionsAdd = { hourCycle }
        options = Object.assign(options, optionsAdd)
    }
    if (formatMatcher !== undefined) {
        const optionsAdd = { formatMatcher }
        options = Object.assign(options, optionsAdd)
    }
    if (weekDay !== undefined) {
        const optionsAdd = { weekDay }
        options = Object.assign(options, optionsAdd)
    }
    if (era !== undefined) {
        const optionsAdd = { era }
        options = Object.assign(options, optionsAdd)
    }
    if (year !== undefined) {
        const optionsAdd = { year }
        options = Object.assign(options, optionsAdd)
    }
    if (month !== undefined) {
        const optionsAdd = { month }
        options = Object.assign(options, optionsAdd)
    }
    if (day !== undefined) {
        const optionsAdd = { day }
        options = Object.assign(options, optionsAdd)
    }
    if (hour !== undefined) {
        const optionsAdd = { hour }
        options = Object.assign(options, optionsAdd)
    }
    if (minute !== undefined) {
        const optionsAdd = { minute }
        options = Object.assign(options, optionsAdd)
    }
    if (second !== undefined) {
        const optionsAdd = { second }
        options = Object.assign(options, optionsAdd)
    }
    if (fractionalSecondDigits !== undefined) {
        const optionsAdd = { fractionalSecondDigits }
        options = Object.assign(options, optionsAdd)
    }
    if (timeZoneNameStyle !== undefined) {
        const optionsAdd = { timeZoneNameStyle }
        options = Object.assign(options, optionsAdd)
    }

    return new Intl.DateTimeFormat(locales, options)
}

/**
 * Return the current date and time as ISO ISO 8601 string as UTC.
 *
 * @returns The current date and time as ISO ISO 8601 string as UTC.
 */
function isoDateTimeNow() {
    return function () {
        const today = new Date()

        return today.toISOString()
    }
}

/**
 * Return the given date and time as ISO ISO 8601 string as UTC.
 * @param {number} year - The Year
 * @param {number} monthIdx - The index of the month, starting at 0 (January)
 * @param {number} day - The day of the month (starting at 1)
 * @param {number} hour - The hour
 * @param {number} minutes - The minutes
 * @param {number} seconds - The seconds
 * @returns The given date and time as ISO ISO 8601 string as UTC.
 */
function isoDateTimeJS(year, monthIdx, day, hour, minutes, seconds) {
    const date = new Date(year, monthIdx, day, hour, minutes, seconds)
    return date.toISOString()
}

/**
 * Return a string of the current date and time formatted using the given
 * formatter object.
 *
 * @param {Intl.DateTimeFormat} formatter - The format to use to format the
 *                                          output.
 * @returns A string of the current date and time formatted using the given
 *          formatter object.
 */
function formatDateTimeNow(formatter) {
    return function () {
        const today = new Date()

        return formatter.format(today)
    }
}

/**
 * Return the given local date formatted by the given formatter.
 *
 * @param {Intl.DateTimeFormat} formatter - The formatter to use
 * @param {number} year - The Year
 * @param {number} monthIdx - The index of the month, starting at 0 (January)
 * @param {number} day - The day of the month (starting at 1)
 * @returns The given date formatted by the given formatter.
 */
function formatDateJS(formatter, year, monthIdx, day) {
    const date = new Date(year, monthIdx, day)
    return formatter.format(date)
}

/**
 * Return the given local date and time formatted by the given formatter.
 *
 * @param {Intl.DateTimeFormat} formatter - The formatter to use
 * @param {number} year - The Year
 * @param {number} monthIdx - The index of the month, starting at 0 (January)
 * @param {number} day - The day of the month (starting at 1)
 * @param {number} hour - The hour
 * @param {number} minutes - The minutes
 * @param {number} seconds - The seconds
 * @returns The given date and time formatted by the given formatter.
 */
function formatDateTimeJS(
    formatter,
    year,
    monthIdx,
    day,
    hour,
    minutes,
    seconds
) {
    const date = new Date(year, monthIdx, day, hour, minutes, seconds)
    return formatter.format(date)
}