/p093_includes/Date.php

<?php
class Date {
    protected $_time;
    protected $_workingDaysCalendar = array('Mon', 'Tue', 'Wed', 'Thu', 'Fri');

    const DAYS = 'day';
    const MINUTES = 'minute';
    const HOURS = 'hour';

    public static function create()
    {
        return new Date();
    }

    public function  __construct($date = null)
    {
        if (!$date)
        {
            $this->_time = time();
            return;
        }

        if (is_string($date))
        {
            $this->_time = strtotime($date);
        }
        elseif ($date instanceof self)
        {
            $this->_time = $date->getTime();
        }
        elseif (is_numeric ((int) $date))
        {
            $this->_time = $date;
        }
    }

    public static function reverse($date)
    {
        $dateTime = preg_split('/\s/', trim($date));

        if (count($dateTime) == 0) {
            return $date;
        }

        $date = array_shift($dateTime);
        $time = '';
        if (!empty($dateTime)) {
            $time = array_shift($dateTime);
        }

        $dateTime = implode('-', array_reverse(preg_split('/\//', $date)));

        if (!empty($time)) {
            $dateTime .= " $time";
        }

        return $dateTime;
    }

    public static function format($format, $date = true) {
        if ($date === true) {
            $date = time();
        }

        if (is_int($date)) {
            return date($format, $date);
        }

        return date($format, strtotime($date));
    }

    public function getFormatted($format)
    {
        return Date::format($format, $this->getTime());
    }

    public static function now($includeTime = true)
    {
        if ($includeTime)
        {
            return date('Y-m-d H:i:s');
        }

        return date('Y-m-d');
    }

    public static function tomorrow($includeTime = true)
    {
        $format = 'Y-m-d H:i:s';
        if (!$includeTime)
        {
            $format = 'Y-m-d';
        }

        return date($format, strtotime("+1 day"));
    }

    public static function dayAfterTomorrow($includeTime = true)
    {
        $format = 'Y-m-d H:i:s';
        if (!$includeTime)
        {
            $format = 'Y-m-d';
        }

        return date($format, strtotime("+2 day"));
    }

    public function grossDaysUntil($until, $options = array())
    {
       $default = array('workingSchedule' => array('Mon' => array('8:00', '17:00'),
                                                   'Tue' => array('8:00', '17:00'),
                                                   'Wed' => array('8:00', '17:00'),
                                                   'Thu' => array('8:00', '17:00'),
                                                   'Fri' => array('8:00', '17:00'),
                                                   'Sat' => array('8:00', '17:00'),
                                                   'Sun' => array('8:00', '17:00')),
                        'hoursPerDay' => 9,
                        'lunchBreakHours' => 0);

        $options = array_merge($default, $options);

        return $this->workingDaysUntil($until, $options);
    }

    public function daysUntil($until, $exclude = array())
    {
        $secondsPerDay = 86400;

        $until = strtotime(date('Y-m-d', strtotime($until)));
        $time = strtotime(date("Y-m-d", $this->_time));

        return ($until - $time) / $secondsPerDay;
    }

    public function toSqlDate()
    {
        return date('Y-m-d H:i:s', $this->_time);
    }

    public function hoursUntil($until)
    {
        return (strtotime($until) - $this->_time) / 3600;
    }

    public function workingDaysUntil($until, $options = array())
    {
        if ($this->_time == strtotime($until))
        {
            return 0;
        }

        $default = array('workingSchedule' => array('Mon' => array('8:00', '17:00'),
                                                    'Tue' => array('8:00', '17:00'),
                                                    'Wed' => array('8:00', '17:00'),
                                                    'Thu' => array('8:00', '17:00'),
                                                    'Fri' => array('8:00', '17:00'),
                                                    'Sat' => array('8:00', '12:00')),
                         'hoursPerDay' => 9,
                         'lunchBreakHours' => 0);

        $options = array_merge($default, $options);
        $workingSchedule = $options['workingSchedule'];

        $currentTimestamp = strtotime(date('Y-m-d', $this->_time));
        $endTimestamp = strtotime(date('Y-m-d', strtotime($until)));
        $dayCount = 0;
        while ($currentTimestamp <= $endTimestamp)
        {
            if (!empty($workingSchedule[date('D', $currentTimestamp)]))
            {
                $currentSchedule = $workingSchedule[date('D', $currentTimestamp)];
                $d = new Date($currentSchedule[0]);
                $hoursPerDay = $d->hoursUntil($currentSchedule[1]);

                if ($hoursPerDay > 6)
                {
                    $hoursPerDay -= $options['lunchBreakHours'];
                }

                $dayCount += $hoursPerDay / $options['hoursPerDay'];
            }

            $currentTimestamp = strtotime('+1 day', $currentTimestamp);
        }

        $dates = array('start' => $this->toSqlDate(), 'end' => $until);
        foreach($dates as $tag => $date)
        {
            $timestamp = strtotime($date);
            $weekDay = date('D', $timestamp);

            if (!empty($workingSchedule[$weekDay]))
            {
                $dayStartTime = strtotime($workingSchedule[$weekDay][0]);
                $dayEndTime = strtotime($workingSchedule[$weekDay][1]);

                $dateTime = strtotime(date('H:i', strtotime($date)));
                if ($dateTime < $dayStartTime)
                {
                    $dateTime = $dayStartTime;
                }
                elseif ($dateTime > $dayEndTime)
                {
                    $dateTime = $dayEndTime;
                }

                $diff = $dateTime - $dayStartTime;
                if ($tag == 'end')
                {
                    $diff = $dayEndTime - $dateTime;
                }

                if ($diff > 0)
                {
                    $dayCount -= (($diff) / (60 * 60)) / $options['hoursPerDay'];
                }
            }
        }

        return round($dayCount, 2);
    }


    public function  __toString()
    {
        return $this->toSqlDate();
    }

    public function isSQLValid($date)
    {
        $tokens = preg_split('/-/', $date);
        if (count($tokens) != 3)
        {
            return false;
        }

        $year = (int) array_shift($tokens);
        $month = (int) array_shift($tokens);
        $day = (int) array_shift($tokens);

        if ($year <= 0 || $month <= 0 || $day <= 0)
        {
            return false;
        }

        return checkdate($month, $day, $year);
    }

    public function dayOfWeek($mondayFirst = true)
    {
        return (int) date('N', $this->_time);
    }

    public function isWorkingDay()
    {
        $currentDay = ucfirst(date('D', $this->_time));
        return in_array($currentDay, $this->_workingDaysCalendar);
    }

    public function nextDay()
    {
        return new Date(strtotime('+1 day', $this->_time));
    }

    public function prevDay()
    {
        return new Date(strtotime('-1 day', $this->_time));
    }

    public function nextMonth()
    {
        return new Date(strtotime('+1 month', $this->_time));
    }

    public function workingDayOfMonth()
    {
        if (!$this->isWorkingDay())
        {
            return -1;
        }

        $current = $this->_time;
        $count = 1;
        while(((int) date('j', $current)) > 1)
        {
            $current = strtotime('-1 day', $current);
            $currentDay = new Date($current);

            if ($currentDay->isWorkingDay())
            {
                $count++;
            }
        }

        return $count;
    }

    public function getWorkingDaysOfMonthCount()
    {
        $count = 0;

        $current = new Date(date('Y-m-01', $this->_time));
        $current->setWorkingDaysCalendar($this->_workingDaysCalendar);
        $end = new Date(date('Y-m-t', $this->_time));

        while ($current->getTime(false) <= $end->getTime(false))
        {
            if ($current->isWorkingDay())
            {
                $count++;
            }

            $current = new Date($current->nextDay());
            $current->setWorkingDaysCalendar($this->_workingDaysCalendar);
        }

        return $count;
    }

    public function getWorkDayOfMonthIndex()
    {
        $count = 0;

        $current = new Date(date('Y-m-01', $this->_time));
        $current->setWorkingDaysCalendar($this->_workingDaysCalendar);

        while ($current->getTime(false) <= $this->getTime(false))
        {
            if ($current->isWorkingDay())
            {
                $count++;
            }

            $current = new Date($current->nextDay());
            $current->setWorkingDaysCalendar($this->_workingDaysCalendar);
        }

        return $count;
    }

    public function getTime($includeTime = true)
    {
        if (!$includeTime)
        {
            return strtotime(date('Y-m-d', $this->_time));
        }

        return $this->_time;
    }

    public function getDate()
    {
        return new Date(date('Y-m-d', $this->_time));
    }

    public function toFormat($format)
    {
        return date($format, $this->_time);
    }

    public function add($value, $unit = self::DAYS)
    {
        if ($value > 0)
        {
            $this->_time = strtotime("+{$value} {$unit}", $this->_time);
            return $this;
        }

        $this->_time = strtotime("-{$value} {$unit}", $this->_time);
        return $this;
    }

    public function compare(self $date)
    {
        if ($this->getTime() > $date->getTime())
        {
            return 1;
        }
        elseif ($this->getTime() < $date->getTime())
        {
            return -1;
        }

        return 0;
    }

    public function setTime($time)
    {
        $this->_time = $time;
    }

    public function setWorkingDaysCalendar($workingDaysCalendar)
    {
        $this->_workingDaysCalendar = $workingDaysCalendar;
    }

}