<?php
namespace extend;
class Time
{
    /**
     * 返回今日开始和结束的时间戳
     *
     * @return array
     */
    public static function today()
    {
        list($y, $m, $d) = explode('-', date('Y-m-d'));
        return [
            mktime(0, 0, 0, $m, $d, $y),
            mktime(23, 59, 59, $m, $d, $y)
        ];
    }

    /**
     * 返回昨日开始和结束的时间戳
     *
     * @return array
     */
    public static function yesterday()
    {
        $yesterday = date('d') - 1;
        return [
            mktime(0, 0, 0, date('m'), $yesterday, date('Y')),
            mktime(23, 59, 59, date('m'), $yesterday, date('Y'))
        ];
    }

    /**
     * 返回本周开始和结束的时间戳
     *
     * @return array
     */
    public static function week()
    {
        list($y, $m, $d, $w) = explode('-', date('Y-m-d-w'));
        if($w == 0) $w = 7; //修正周日的问题
        return [
            mktime(0, 0, 0, $m, $d - $w + 1, $y), mktime(23, 59, 59, $m, $d - $w + 7, $y)
        ];
    }

    /**
     * 返回上周开始和结束的时间戳
     *
     * @return array
     */
    public static function lastWeek()
    {
        $timestamp = time();
        return [
            strtotime(date('Y-m-d', strtotime("last week Monday", $timestamp))),
            strtotime(date('Y-m-d', strtotime("last week Sunday", $timestamp))) + 24 * 3600 - 1
        ];
    }

    /**
     * 返回本月开始和结束的时间戳
     *
     * @return array
     */
    public static function month($everyDay = false)
    {
        list($y, $m, $t) = explode('-', date('Y-m-t'));
        return [
            mktime(0, 0, 0, $m, 1, $y),
            mktime(23, 59, 59, $m, $t, $y)
        ];
    }

    /**
     * 返回上个月开始和结束的时间戳
     *
     * @return array
     */
    public static function lastMonth()
    {
        $y = date('Y');
        $m = date('m');
        $begin = mktime(0, 0, 0, $m - 1, 1, $y);
        $end = mktime(23, 59, 59, $m - 1, date('t', $begin), $y);

        return [$begin, $end];
    }

    /**
     * 返回今年开始和结束的时间戳
     *
     * @return array
     */
    public static function year()
    {
        $y = date('Y');
        return [
            mktime(0, 0, 0, 1, 1, $y),
            mktime(23, 59, 59, 12, 31, $y)
        ];
    }

    /**
     * 返回去年开始和结束的时间戳
     *
     * @return array
     */
    public static function lastYear()
    {
        $year = date('Y') - 1;
        return [
            mktime(0, 0, 0, 1, 1, $year),
            mktime(23, 59, 59, 12, 31, $year)
        ];
    }

    public static function dayOf()
    {

    }

    /**
     * 获取几天前零点到现在/昨日结束的时间戳
     *
     * @param int $day 天数
     * @param bool $now 返回现在或者昨天结束时间戳
     * @return array
     */
    public static function dayToNow($day = 1, $now = true)
    {
        $end = time();
        if (!$now) {
            list($foo, $end) = self::yesterday();
        }
        return [
            mktime(0, 0, 0, date('m'), date('d') - $day, date('Y')),
            $end
        ];
    }

    /**
     * 返回几天前的时间戳
     *
     * @param int $day
     * @return int
     */
    public static function daysAgo($day = 1)
    {
        $nowTime = time();
        return $nowTime - self::daysToSecond($day);
    }

    /**
     * 返回几天后的时间戳
     *
     * @param int $day
     * @return int
     */
    public static function daysAfter($day = 1)
    {
        $nowTime = time();
        return $nowTime + self::daysToSecond($day);
    }

    /**
     * 天数转换成秒数
     *
     * @param int $day
     * @return int
     */
    public static function daysToSecond($day = 1)
    {
        return $day * 86400;
    }

    /**
     * 周数转换成秒数
     *
     * @param int $week
     * @return int
     */
    public static function weekToSecond($week = 1)
    {
        return self::daysToSecond() * 7 * $week;
    }

    private static function startTimeToEndTime()
    {

    }

    public static function getDownTimes($time_s, $time_n)
    {
        $strtime = '';
        $time = $time_n - $time_s;
        if ($time >= 86400) {
            $strtime .= intval($time / 86400).'天';
            $time = $time % 86400;
        }
        if ($time >= 3600) {
            $strtime .= intval($time / 3600) . '时';
            $time = $time % 3600;
        } else {
            $strtime .= '';
        }
        if ($time >= 60) {
            $strtime .= intval($time / 60) . '分';
            $time = $time % 60;
        } else {
            $strtime .= '';
        }
        if ($time > 0) {
            $strtime .= intval($time) . '秒';
        } else {
            $strtime = "";
        }
        return $strtime;
    }
}