<?php
/**
 * The date class file of ZenTaoPHP framework.
 *
 * The author disclaims copyright to this source code.  In place of
 * a legal notice, here is a blessing:
 * 
 *  May you do good and not evil.
 *  May you find forgiveness for yourself and forgive others.
 *  May you share freely, never taking more than you give.
 */
/**
 * Date class.
 * 
 * @package framework
 */
class date 
{
    /**
     * Build hour time list.
     * 
     * @param  int $begin 
     * @param  int $end 
     * @param  int $delta 
     * @access public
     * @return array
     */
    public static function buildTimeList($begin, $end, $delta)
    {
        $times = array();
        for($hour = $begin; $hour <= $end; $hour ++)
        {
            for($minutes = 0; $minutes < 60; $minutes += $delta)
            {
                $time  = sprintf('%02d%02d', $hour, $minutes);
                $label = sprintf('%02d:%02d', $hour, $minutes);
                $times[$time] = $label;
            }
        }
        return $times;
    }

    /**
     * Get today.
     * 
     * @access public
     * @return date
     */
    public static function today()
    {
        return date(DT_DATE2, time());
    }

    /**
     * Get yesterday 
     * 
     * @access public
     * @return date
     */
    public static function yesterday()
    {
        return date(DT_DATE1, strtotime('yesterday'));
    }

    /**
     * Get tomorrow.
     * 
     * @access public
     * @return date
     */
    public static function tomorrow()
    {
        return date(DT_DATE1, strtotime('tomorrow'));
    }

    /**
     * Get the day before yesterday.
     * 
     * @access public
     * @return date
     */
    public static function twoDaysAgo()
    {
        return date(DT_DATE1, strtotime('-2 days'));
    }

    /**
     * Get now time period.
     * 
     * @param  int    $delta 
     * @access public
     * @return string the current time period, like 0915
     */
    public static function now($delta = 10)
    {
        $range  = range($delta, 60 - $delta, $delta);
        $hour   = date('H', time());
        $minute = date('i', time());

        if($minute > 60 - $delta)
        {
            $hour += 1;
            $minute = 00;
        }
        else
        {
            for($i = 0; $i < $delta; $i ++)
            {
                if(in_array($minute + $i, $range))
                {
                    $minute = $minute + $i;
                    break;
                }
            }
        }

        return sprintf('%02d%02d', $hour, $minute);
    }

    /**
     * Format time 0915 to 09:15
     * 
     * @param  string $time 
     * @access public
     * @return string
     */
    public static function formatTime($time)
    {
        if(strlen($time) != 4 or $time == '2400') return '';
        return substr($time, 0, 2) . ':' . substr($time, 2, 2);
    }

    /**
     * Get the begin and end date of this week.
     * 
     * @access public
     * @return array
     */
    public static function getThisWeek()
    {
        $baseTime = self::getMiddleOfThisWeek();
        $begin = date(DT_DATE1, strtotime('last monday', $baseTime)) . ' 00:00:00';
        $end   = date(DT_DATE1, strtotime('next sunday', $baseTime)) . ' 23:59:59';
        return array('begin' => $begin, 'end' => $end);
    }

    /**
     * Get the begin and end date of last week.
     * 
     * @access public
     * @return array
     */
    public static function getLastWeek()
    {
        $baseTime = self::getMiddleOfLastWeek();
        $begin = date(DT_DATE1, strtotime('last monday', $baseTime)) . ' 00:00:00';
        $end   = date(DT_DATE1, strtotime('next sunday', $baseTime)) . ' 23:59:59';
        return array('begin' => $begin, 'end' => $end);
    }

    /**
     * Get the time at the middle of this week.
     * 
     * If today in week is 1, move it one day in future. Else is 7, move it back one day. To keep the time geted in this week.
     *
     * @access public
     * @return time
     */
    public static function getMiddleOfThisWeek()
    {
        $baseTime = time();
        $weekDay  = date('N');
        if($weekDay == 1) $baseTime = time() + 86400;
        if($weekDay == 7) $baseTime = time() - 86400;
        return $baseTime;
    }

    /**
     * Get middle of last week 
     * 
     * @access public
     * @return time
     */
    public static function getMiddleOfLastWeek()
    {
        $baseTime = time();
        $weekDay  = date('N');
        $baseTime = time() - 86400 * 7;
        if($weekDay == 1) $baseTime = time() - 86400 * 4;  // Make sure is last thursday.
        if($weekDay == 7) $baseTime = time() - 86400 * 10; // Make sure is last thursday.
        return $baseTime;
    }

    /**
     * Get this month begin and end time
     * 
     * @access public
     * @return array
     */
    public static function getThisMonth()
    {
        $begin = date('Y-m') . '-01 00:00:00';
        $end   = date('Y-m', strtotime('next month')) . '-00 23:59:59';
        return array('begin' => $begin, 'end' => $end);
    }

    /**
     * Get last month begin and end time
     * 
     * @access public
     * @return array
     */
    public static function getLastMonth()
    {
        $begin = date('Y-m', strtotime('last month')) . '-01 00:00:00';
        $end   = date('Y-m', strtotime('this month')) . '-00 23:59:59';
        return array('begin' => $begin, 'end' => $end);
    }

    public static function getThisSeason()
    {
        $year  = date("Y-");
        $month = date("n");
        if($month % 3)
        {
            $seasonBegin = $month - ($month % 3) + 1;
            $seasonEnd   = $seasonBegin + 3;
        }
        else
        {
            $seasonEnd   = $month + 1;
            $seasonBegin = $seasonEnd - 3;
        }

        if(strlen($seasonBegin) == 1) $seasonBegin = "0$seasonBegin";
        if(strlen($seasonEnd) == 1)   $seasonEnd   = "0$seasonEnd";
        $begin = $year . $seasonBegin;
        $end   = $year . $seasonEnd;

        return array('begin' => $begin, 'end' => $end);
    }

    public static function getThisYear()
    {
        $begin = date(DT_DATE1, strtotime('1/1 this year'));
        $end   = date(DT_DATE1, strtotime('1/1 next year -1 day'));  
        return array('begin' => $begin, 'end' => $end);
    }
}