/** Constants used for time computations */
import { getDate, getTime, parseInt } from "../2.base";
import { i18nText } from "../utils";
import { StartOfWeek } from "../constant";
import { isKhtml } from "../platform/web";
import { _global } from "../0.foundation";

const SECOND = 1000;
const MINUTE = 60 * SECOND;
const HOUR = 60 * MINUTE;
const DAY = 24 * HOUR;
const WEEK = 7 * DAY;
const _FD = 1;
const _SMN = [
    0,
    1,
    2,
    3,
    4,
    5,
    6,
    7,
    8,
    9,
    10,
    11
];
const _MD = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31];
const _OFFSET = [0, -1, -2, -3, -4, -5, -6]; // 实际上无论周几作为一周的第一天，周初周末都是在-6-0间做偏移，用一个数组就可以

export const Date = {
    SECOND,
    MINUTE,
    HOUR,
    DAY,
    WEEK,
    _FD,
    _SMN,
    _MD,
    _OFFSET,
};

/**
 * 获取时区
 * @returns {String}
 */
export function getTimezone(date) {
    return date.toString().replace(/^.* (?:\((.*)\)|([A-Z]{1,4})(?:[-+][0-9]{4})?(?: -?\d+)?)$/, "$1$2").replace(/[^A-Z]/g, "");
}

/**
 * Returns the number of days in the current month
 */
export function getMonthDays(date, month = date.getMonth()) {
    const year = date.getFullYear();
    if (((0 === (year % 4)) && ((0 !== (year % 100)) || (0 === (year % 400)))) && month === 1) {
        return 29;
    }

    return _MD[month];
}

/**
 * 获取每月的最后一天
 * @returns {Date}
 */
export function getLastDateOfMont(date) {
    return getDate(date.getFullYear(), date.getMonth(), getMonthDays(date));
}

/**
 * 获取每月的最后一天
 * @returns {Date}
 */
export function getLastDateOfMonth(date) {
    return getDate(date.getFullYear(), date.getMonth(), getMonthDays(date));
}

/**
 * Returns the number of day in the year.
 * @param date
 * @returns {number}
 */
export function getDayOfYear(date) {
    const now = getDate(date.getFullYear(), date.getMonth(), date.getDate(), 0, 0, 0);
    const then = getDate(date.getFullYear(), 0, 0, 0, 0, 0);
    const time = now - then;

    return Math.floor(time / DAY);
}


/**
 * Returns the number of the week in year, as defined in ISO 8601.
 * @param date
 * @returns {number}
 */
export function getWeekNumber(date) {
    const d = getDate(date.getFullYear(), date.getMonth(), date.getDate(), 0, 0, 0);
    const week = d.getDay();
    const startOfWeek = StartOfWeek % 7;
    let middleDay = (startOfWeek + 3) % 7;
    middleDay = middleDay || 7;
    // 偏移到周周首之前需要多少天
    const offsetWeekStartCount = week < startOfWeek ? (7 + week - startOfWeek) : (week - startOfWeek);
    const offsetWeekMiddleCount = middleDay < startOfWeek ? (7 + middleDay - startOfWeek) : (middleDay - startOfWeek);
    d.setDate(d.getDate() - offsetWeekStartCount + offsetWeekMiddleCount);
    const ms = d.valueOf();
    d.setMonth(0);
    d.setDate(1);

    return Math.floor((ms - d.valueOf()) / (7 * 864e5)) + 1;
}

export function getQuarter(date) {
    return Math.floor(date.getMonth() / 3) + 1;
}

/**
 * 离当前时间多少天的时间
 * @param date
 * @param offset
 * @returns {Date}
 */
export function getOffsetDate(date, offset) {
    return getDate(getTime(date.getFullYear(), date.getMonth(), date.getDate(), date.getHours(), date.getMinutes(), date.getSeconds()) + offset * 864e5);
}

export function getOffsetQuarter(date, n) {
    const dt = getDate(getTime(date.getFullYear(), date.getMonth(), date.getDate(), date.getHours(), date.getMinutes(), date.getSeconds()));
    let day = dt.getDate();
    const monthDay = getMonthDays(getDate(dt.getFullYear(), dt.getMonth() + parseInt(n, 10) * 3, 1));
    if (day > monthDay) {
        day = monthDay;
    }
    dt.setDate(day);
    dt.setMonth(dt.getMonth() + parseInt(n, 10) * 3);

    return dt;
}

/**
 * 得到本季度的起始月份
 * @param date
 * @returns {number}
 */
export function getQuarterStartMonth(date) {
    let quarterStartMonth = 0;
    const nowMonth = date.getMonth();
    if (nowMonth < 3) {
        quarterStartMonth = 0;
    }
    if (2 < nowMonth && nowMonth < 6) {
        quarterStartMonth = 3;
    }
    if (5 < nowMonth && nowMonth < 9) {
        quarterStartMonth = 6;
    }
    if (nowMonth > 8) {
        quarterStartMonth = 9;
    }

    return quarterStartMonth;
}

/**
 * 获得本季度的起始日期
 * @param date
 * @returns {Date}
 */
export function getQuarterStartDate(date) {
    return getDate(date.getFullYear(), getQuarterStartMonth(date), 1);
}

/**
 * 得到本季度的结束日期
 * @param date
 * @returns {Date}
 */
export function getQuarterEndDate(date) {
    const quarterEndMonth = getQuarterStartMonth(date) + 2;

    return getDate(date.getFullYear(), quarterEndMonth, getMonthDays(date, quarterEndMonth));
}

/**
 * 指定日期n个月之前或之后的日期
 * @param date
 * @param n
 * @returns {Date}
 */
export function getOffsetMonth(date, n) {
    const dt = getDate(getTime(date.getFullYear(), date.getMonth(), date.getDate(), date.getHours(), date.getMinutes(), date.getSeconds()));
    let day = dt.getDate();
    const monthDay = getMonthDays(getDate(dt.getFullYear(), dt.getMonth() + parseInt(n, 10), 1));
    if (day > monthDay) {
        day = monthDay;
    }
    dt.setDate(day);
    dt.setMonth(dt.getMonth() + parseInt(n, 10));

    return dt;
}

/**
 * 获得本周的起始日期
 * @param date
 * @returns {Date}
 */
export function getWeekStartDate(date) {
    const w = date.getDay();
    const startOfWeek = StartOfWeek % 7;

    return getOffsetDate(date, _OFFSET[w < startOfWeek ? (7 + w - startOfWeek) : (w - startOfWeek)]);
}

/**
 * 得到本周的结束日期
 * @param date
 * @returns {Date}
 */
export function getWeekEndDate(date) {
    const w = date.getDay();
    const startOfWeek = StartOfWeek % 7;

    return getOffsetDate(date, _OFFSET[w < startOfWeek ? (7 + w - startOfWeek) : (w - startOfWeek)] + 6);
}

export function getFullDayName(index) {
    return [
        i18nText("BI-Basic_Sunday"),
        i18nText("BI-Basic_Monday"),
        i18nText("BI-Basic_Tuesday"),
        i18nText("BI-Basic_Wednesday"),
        i18nText("BI-Basic_Thursday"),
        i18nText("BI-Basic_Friday"),
        i18nText("BI-Basic_Saturday"),
        i18nText("BI-Basic_Sunday")
    ][index];
}

export function getShortDayName(index) {
    return [
        i18nText("BI-Basic_Simple_Sunday"),
        i18nText("BI-Basic_Simple_Monday"),
        i18nText("BI-Basic_Simple_Tuesday"),
        i18nText("BI-Basic_Simple_Wednesday"),
        i18nText("BI-Basic_Simple_Thursday"),
        i18nText("BI-Basic_Simple_Friday"),
        i18nText("BI-Basic_Simple_Saturday"),
        i18nText("BI-Basic_Simple_Sunday")
    ][index];
}

export function getMonthName(index) {
    return [
        i18nText("BI-Basic_January"),
        i18nText("BI-Basic_February"),
        i18nText("BI-Basic_March"),
        i18nText("BI-Basic_April"),
        i18nText("BI-Basic_May"),
        i18nText("BI-Basic_June"),
        i18nText("BI-Basic_July"),
        i18nText("BI-Basic_August"),
        i18nText("BI-Basic_September"),
        i18nText("BI-Basic_October"),
        i18nText("BI-Basic_November"),
        i18nText("BI-Basic_December")
    ][index];
}

export function getQuarterName(index) {
    return [
        "",
        i18nText("BI-Quarter_1"),
        i18nText("BI-Quarter_2"),
        i18nText("BI-Quarter_3"),
        i18nText("BI-Quarter_4")
    ][index];
}

/**
 * 格式化打印日期
 * @param date
 * @param str
 * @returns {*}
 */
export function print(date, str) {
    const m = date.getMonth();
    const d = date.getDate();
    const y = date.getFullYear();
    let yWith4number = `${y}`;
    while (yWith4number.length < 4) {
        yWith4number = `0${yWith4number}`;
    }
    const wn = getWeekNumber(date);
    const qr = getQuarter(date);
    const w = date.getDay();
    const s = {};
    const hr = date.getHours();
    const pm = (hr >= 12);
    let ir = (pm) ? (hr - 12) : hr;
    const dy = getDayOfYear(date);
    if (ir === 0) {
        ir = 12;
    }
    const min = date.getMinutes();
    const sec = date.getSeconds();
    s["%a"] = getShortDayName(w); // abbreviated weekday name [FIXME: I18N]
    s["%A"] = getFullDayName(w); // full weekday name
    s["%b"] = _SMN[m]; // abbreviated month name [FIXME: I18N]
    s["%B"] = getMonthName(m); // full month name
    // FIXME: %c : preferred date and time representation for the current locale
    s["%C"] = 1 + Math.floor(y / 100); // the century number
    s["%d"] = (d < 10) ? (`0${d}`) : d; // the day of the month (range 01 to 31)
    s["%e"] = d; // the day of the month (range 1 to 31)
    // FIXME: %D : american date style: %m/%d/%y
    // FIXME: %E, %F, %G, %g, %h (man strftime)
    s["%H"] = (hr < 10) ? (`0${hr}`) : hr; // hour, range 00 to 23 (24h format)
    s["%I"] = (ir < 10) ? (`0${ir}`) : ir; // hour, range 01 to 12 (12h format)
    s["%j"] = (dy < 100) ? ((dy < 10) ? (`00${dy}`) : (`0${dy}`)) : dy; // day of the year (range 001 to 366)
    s["%k"] = `${hr}`;		// hour, range 0 to 23 (24h format)
    s["%l"] = `${ir}`;		// hour, range 1 to 12 (12h format)
    s["%X"] = (m < 9) ? (`0${1 + m}`) : (1 + m); // month, range 01 to 12
    s["%x"] = m + 1; // month, range 1 to 12
    s["%M"] = (min < 10) ? (`0${min}`) : min; // minute, range 00 to 59
    s["%n"] = "\n";		// a newline character
    s["%p"] = pm ? "PM" : "AM";
    s["%P"] = pm ? "pm" : "am";
    // FIXME: %r : the time in am/pm notation %I:%M:%S %p
    // FIXME: %R : the time in 24-hour notation %H:%M
    s["%s"] = Math.floor(date.getTime() / 1000);
    s["%S"] = (sec < 10) ? (`0${sec}`) : sec; // seconds, range 00 to 59
    s["%t"] = "\t";		// a tab character
    // FIXME: %T : the time in 24-hour notation (%H:%M:%S)
    s["%U"] = s["%W"] = s["%V"] = (wn < 10) ? (`0${wn}`) : wn;
    s["%u"] = w + 1;	// the day of the week (range 1 to 7, 1 = MON)
    s["%w"] = w;		// the day of the week (range 0 to 6, 0 = SUN)
    // FIXME: %x : preferred date representation for the current locale without the time
    // FIXME: %X : preferred time representation for the current locale without the date
    s["%y"] = yWith4number.substr(2, 2); // year without the century (range 00 to 99)
    s["%Y"] = yWith4number;		// year with the century
    s["%%"] = "%";		// a literal '%' character
    s["%q"] = `0${qr}`;
    s["%Q"] = qr;

    let re = /%./g;
    const isNewKhtml = isKhtml || function () {
        if (!_global.navigator) {
            return false;
        }

        return /Konqueror|Safari|KHTML/i.test(navigator.userAgent);
    };

    // 包含年周的格式化，ISO8601标准周的计数会影响年
    if ((str.indexOf("%Y") !== -1 || str.indexOf("%y") !== -1) && (str.indexOf("%W") !== -1 || str.indexOf("%U") !== -1 || str.indexOf("%V") !== -1)) {
        switch (wn) {
            // 如果周数是1，但是当前却在12月，表示此周数为下一年的
            case 1:
                if (m === 11) {
                    s["%y"] = parseInt(s["%y"]) + 1;
                    s["%Y"] = parseInt(s["%Y"]) + 1;
                }
                break;
            // 如果周数是53，但是当前却在1月，表示此周数为上一年的
            case 53:
                if (m === 0) {
                    s["%y"] = parseInt(s["%y"]) - 1;
                    s["%Y"] = parseInt(s["%Y"]) - 1;
                }
                break;
            default:
                break;
        }
    }

    if (!isNewKhtml()) {
        return str.replace(re, par => s[par] || par);
    }
    const a = str.match(re);
    for (let i = 0; i < a.length; i++) {
        const tmp = s[a[i]];
        if (tmp) {
            re = new RegExp(a[i], "g");
            str = str.replace(re, tmp);
        }
    }

    return str;
}