<?php

/**

 * Zend Framework

 *

 * LICENSE

 *

 * This source file is subject to the new BSD license that is bundled

 * with this package in the file LICENSE.txt.

 * It is also available through the world-wide-web at this URL:

 * http://framework.zend.com/license/new-bsd

 * If you did not receive a copy of the license and are unable to

 * obtain it through the world-wide-web, please send an email

 * to license@zend.com so we can send you a copy immediately.

 *

 * @category   Zend

 * @package    Zend_Date

 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

 * @version    $Id: DateObject.php 22712 2010-07-29 08:24:28Z thomas $

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 */

/**

 * @category   Zend

 * @package    Zend_Date

 * @subpackage Zend_Date_DateObject

 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 */

abstract class Zend_Date_DateObject {

    /**

     * UNIX Timestamp

     */

    private   $_unixTimestamp;

    protected static $_cache         = null;

    protected static $_cacheTags     = false;

    protected static $_defaultOffset = 0;

    /**

     * active timezone

     */

    private   $_timezone    = 'UTC';

    private   $_offset      = 0;

    private   $_syncronised = 0;

    // turn off DST correction if UTC or GMT

    protected $_dst         = true;

    /**

     * Table of Monthdays

     */

    private static $_monthTable = array(31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31);

    /**

     * Table of Years

     */

    private static $_yearTable = array(

        1970 => 0,            1960 => -315619200,   1950 => -631152000,

        1940 => -946771200,   1930 => -1262304000,  1920 => -1577923200,

        1910 => -1893456000,  1900 => -2208988800,  1890 => -2524521600,

        1880 => -2840140800,  1870 => -3155673600,  1860 => -3471292800,

        1850 => -3786825600,  1840 => -4102444800,  1830 => -4417977600,

        1820 => -4733596800,  1810 => -5049129600,  1800 => -5364662400,

        1790 => -5680195200,  1780 => -5995814400,  1770 => -6311347200,

        1760 => -6626966400,  1750 => -6942499200,  1740 => -7258118400,

        1730 => -7573651200,  1720 => -7889270400,  1710 => -8204803200,

        1700 => -8520336000,  1690 => -8835868800,  1680 => -9151488000,

        1670 => -9467020800,  1660 => -9782640000,  1650 => -10098172800,

        1640 => -10413792000, 1630 => -10729324800, 1620 => -11044944000,

        1610 => -11360476800, 1600 => -11676096000);

    /**

     * Set this object to have a new UNIX timestamp.

     *

     * @param  string|integer  $timestamp  OPTIONAL timestamp; defaults to local time using time()

     * @return string|integer  old timestamp

     * @throws Zend_Date_Exception

     */

    protected function setUnixTimestamp($timestamp = null)

    {

        $old = $this->_unixTimestamp;

        if (is_numeric($timestamp)) {

            $this->_unixTimestamp = $timestamp;

        } else if ($timestamp === null) {

            $this->_unixTimestamp = time();

        } else {

            require_once 'Zend/Date/Exception.php';

            throw new Zend_Date_Exception('\'' . $timestamp . '\' is not a valid UNIX timestamp', 0, null, $timestamp);

        }

        return $old;

    }

    /**

     * Returns this object's UNIX timestamp

     * A timestamp greater then the integer range will be returned as string

     * This function does not return the timestamp as object. Use copy() instead.

     *

     * @return  integer|string  timestamp

     */

    protected function getUnixTimestamp()

    {

        if ($this->_unixTimestamp === intval($this->_unixTimestamp)) {

            return (int) $this->_unixTimestamp;

        } else {

            return (string) $this->_unixTimestamp;

        }

    }

    /**

     * Internal function.

     * Returns time().  This method exists to allow unit tests to work-around methods that might otherwise

     * be hard-coded to use time().  For example, this makes it possible to test isYesterday() in Date.php.

     *

     * @param   integer  $sync      OPTIONAL time syncronisation value

     * @return  integer  timestamp

     */

    protected function _getTime($sync = null)

    {

        if ($sync !== null) {

            $this->_syncronised = round($sync);

        }

        return (time() + $this->_syncronised);

    }

    /**

     * Internal mktime function used by Zend_Date.

     * The timestamp returned by mktime() can exceed the precision of traditional UNIX timestamps,

     * by allowing PHP to auto-convert to using a float value.

     *

     * Returns a timestamp relative to 1970/01/01 00:00:00 GMT/UTC.

     * DST (Summer/Winter) is depriciated since php 5.1.0.

     * Year has to be 4 digits otherwise it would be recognised as

     * year 70 AD instead of 1970 AD as expected !!

     *

     * @param  integer  $hour

     * @param  integer  $minute

     * @param  integer  $second

     * @param  integer  $month

     * @param  integer  $day

     * @param  integer  $year

     * @param  boolean  $gmt     OPTIONAL true = other arguments are for UTC time, false = arguments are for local time/date

     * @return  integer|float  timestamp (number of seconds elapsed relative to 1970/01/01 00:00:00 GMT/UTC)

     */

    protected function mktime($hour, $minute, $second, $month, $day, $year, $gmt = false)

    {

        // complete date but in 32bit timestamp - use PHP internal

        if ((1901 < $year) and ($year < 2038)) {

            $oldzone = @date_default_timezone_get();

            // Timezone also includes DST settings, therefor substracting the GMT offset is not enough

            // We have to set the correct timezone to get the right value

            if (($this->_timezone != $oldzone) and ($gmt === false)) {

                date_default_timezone_set($this->_timezone);

            }

            $result = ($gmt) ? @gmmktime($hour, $minute, $second, $month, $day, $year)

                             :   @mktime($hour, $minute, $second, $month, $day, $year);

            date_default_timezone_set($oldzone);

            return $result;

        }

        if ($gmt !== true) {

            $second += $this->_offset;

        }

        if (isset(self::$_cache)) {

            $id = strtr('Zend_DateObject_mkTime_' . $this->_offset . '_' . $year.$month.$day.'_'.$hour.$minute.$second . '_'.(int)$gmt, '-','_');

            if ($result = self::$_cache->load($id)) {

                return unserialize($result);

            }

        }

        // date to integer

        $day   = intval($day);

        $month = intval($month);

        $year  = intval($year);

        // correct months > 12 and months < 1

        if ($month > 12) {

            $overlap = floor($month / 12);

            $year   += $overlap;

            $month  -= $overlap * 12;

        } else {

            $overlap = ceil((1 - $month) / 12);

            $year   -= $overlap;

            $month  += $overlap * 12;

        }

        $date = 0;

        if ($year >= 1970) {

            // Date is after UNIX epoch

            // go through leapyears

            // add months from latest given year

            for ($count = 1970; $count <= $year; $count++) {

                $leapyear = self::isYearLeapYear($count);

                if ($count < $year) {

                    $date += 365;

                    if ($leapyear === true) {

                        $date++;

                    }

                } else {

                    for ($mcount = 0; $mcount < ($month - 1); $mcount++) {

                        $date += self::$_monthTable[$mcount];

                        if (($leapyear === true) and ($mcount == 1)) {

                            $date++;

                        }

                    }

                }

            }

            $date += $day - 1;

            $date = (($date * 86400) + ($hour * 3600) + ($minute * 60) + $second);

        } else {

            // Date is before UNIX epoch

            // go through leapyears

            // add months from latest given year

            for ($count = 1969; $count >= $year; $count--) {

                $leapyear = self::isYearLeapYear($count);

                if ($count > $year)

                {

                    $date += 365;

                    if ($leapyear === true)

                        $date++;

                } else {

                    for ($mcount = 11; $mcount > ($month - 1); $mcount--) {

                        $date += self::$_monthTable[$mcount];

                        if (($leapyear === true) and ($mcount == 2)) {

                            $date++;

                        }

                    }

                }

            }

            $date += (self::$_monthTable[$month - 1] - $day);

            $date = -(($date * 86400) + (86400 - (($hour * 3600) + ($minute * 60) + $second)));

            // gregorian correction for 5.Oct.1582

            if ($date < -12220185600) {

                $date += 864000;

            } else if ($date < -12219321600) {

                $date  = -12219321600;

            }

        }

        if (isset(self::$_cache)) {

            if (self::$_cacheTags) {

                self::$_cache->save( serialize($date), $id, array('Zend_Date'));

            } else {

                self::$_cache->save( serialize($date), $id);

            }

        }

        return $date;

    }

    /**

     * Returns true, if given $year is a leap year.

     *

     * @param  integer  $year

     * @return boolean  true, if year is leap year

     */

    protected static function isYearLeapYear($year)

    {

        // all leapyears can be divided through 4

        if (($year % 4) != 0) {

            return false;

        }

        // all leapyears can be divided through 400

        if ($year % 400 == 0) {

            return true;

        } else if (($year > 1582) and ($year % 100 == 0)) {

            return false;

        }

        return true;

    }

    /**

     * Internal mktime function used by Zend_Date for handling 64bit timestamps.

     *

     * Returns a formatted date for a given timestamp.

     *

     * @param  string   $format     format for output

     * @param  mixed    $timestamp

     * @param  boolean  $gmt        OPTIONAL true = other arguments are for UTC time, false = arguments are for local time/date

     * @return string

     */

    protected function date($format, $timestamp = null, $gmt = false)

    {

        $oldzone = @date_default_timezone_get();

        if ($this->_timezone != $oldzone) {

            date_default_timezone_set($this->_timezone);

        }

        if ($timestamp === null) {

            $result = ($gmt) ? @gmdate($format) : @date($format);

            date_default_timezone_set($oldzone);

            return $result;

        }

        if (abs($timestamp) <= 0x7FFFFFFF) {

            $result = ($gmt) ? @gmdate($format, $timestamp) : @date($format, $timestamp);

            date_default_timezone_set($oldzone);

            return $result;

        }

        $jump      = false;

        $origstamp = $timestamp;

        if (isset(self::$_cache)) {

            $idstamp = strtr('Zend_DateObject_date_' . $this->_offset . '_'. $timestamp . '_'.(int)$gmt, '-','_');

            if ($result2 = self::$_cache->load($idstamp)) {

                $timestamp = unserialize($result2);

                $jump = true;

            }

        }

        // check on false or null alone fails

        if (empty($gmt) and empty($jump)) {

            $tempstamp = $timestamp;

            if ($tempstamp > 0) {

                while (abs($tempstamp) > 0x7FFFFFFF) {

                    $tempstamp -= (86400 * 23376);

                }

                $dst = date("I", $tempstamp);

                if ($dst === 1) {

                    $timestamp += 3600;

                }

                $temp       = date('Z', $tempstamp);

                $timestamp += $temp;

            }

            if (isset(self::$_cache)) {

                if (self::$_cacheTags) {

                    self::$_cache->save( serialize($timestamp), $idstamp, array('Zend_Date'));

                } else {

                    self::$_cache->save( serialize($timestamp), $idstamp);

                }

            }

        }

        if (($timestamp < 0) and ($gmt !== true)) {

            $timestamp -= $this->_offset;

        }

        date_default_timezone_set($oldzone);

        $date   = $this->getDateParts($timestamp, true);

        $length = strlen($format);

        $output = '';

        for ($i = 0; $i < $length; $i++) {

            switch($format[$i]) {

                // day formats

                case 'd':  // day of month, 2 digits, with leading zero, 01 - 31

                    $output .= (($date['mday'] < 10) ? '0' . $date['mday'] : $date['mday']);

                    break;

                case 'D':  // day of week, 3 letters, Mon - Sun

                    $output .= date('D', 86400 * (3 + self::dayOfWeek($date['year'], $date['mon'], $date['mday'])));

                    break;

                case 'j':  // day of month, without leading zero, 1 - 31

                    $output .= $date['mday'];

                    break;

                case 'l':  // day of week, full string name, Sunday - Saturday

                    $output .= date('l', 86400 * (3 + self::dayOfWeek($date['year'], $date['mon'], $date['mday'])));

                    break;

                case 'N':  // ISO 8601 numeric day of week, 1 - 7

                    $day = self::dayOfWeek($date['year'], $date['mon'], $date['mday']);

                    if ($day == 0) {

                        $day = 7;

                    }

                    $output .= $day;

                    break;

                case 'S':  // english suffix for day of month, st nd rd th

                    if (($date['mday'] % 10) == 1) {

                        $output .= 'st';

                    } else if ((($date['mday'] % 10) == 2) and ($date['mday'] != 12)) {

                        $output .= 'nd';

                    } else if (($date['mday'] % 10) == 3) {

                        $output .= 'rd';

                    } else {

                        $output .= 'th';

                    }

                    break;

                case 'w':  // numeric day of week, 0 - 6

                    $output .= self::dayOfWeek($date['year'], $date['mon'], $date['mday']);

                    break;

                case 'z':  // day of year, 0 - 365