<?php

/** 

 * Type to represent DateTime

 * 

 * PHP version 5.3

 * 

 * @category  ODataProducer

 * @package   ODataProducer_Providers_Metadata_Type

 * @author    Anu T Chandy <odataphpproducer_alias@microsoft.com>

 * @copyright 2011 Microsoft Corp. (http://www.microsoft.com)

 * @license   New BSD license, (http://www.opensource.org/licenses/bsd-license.php)

 * @version   SVN: 1.0

 * @link      http://odataphpproducer.codeplex.com

 * 

 */

namespace ODataProducer\Providers\Metadata\Type;

/**

 * Type to represent DateTime

 * 

 * @category  ODataProducer

 * @package   ODataProducer_Providers_Metadata_Type

 * @author    Anu T Chandy <odataphpproducer_alias@microsoft.com>

 * @copyright 2011 Microsoft Corp. (http://www.microsoft.com)

 * @license   New BSD license, (http://www.opensource.org/licenses/bsd-license.php)

 * @version   Release: 1.0

 * @link      http://odataphpproducer.codeplex.com

 */

class DateTime implements IType

{

    /**

     * Gets the type code

     * Note: implementation of IType::getTypeCode

     *   

     * @return TypeCode

     */

    public function getTypeCode()

    {

        return TypeCode::DATETIME;

    }



    /**

     * Checks this type is compactible with another type

     * Note: implementation of IType::isCompatibleWith

     * 

     * @param IType $type Type to check compactibility

     * 

     * @return boolean 

     */

    public function isCompatibleWith(IType $type)

    {

        return ($type->getTypeCode() == TypeCode::DATETIME);

    }



    /**

     * Validate a value in Astoria uri is in a format for this type

     * Note: implementation of IType::validate

     * 

     * @param string $value     The value to validate 

     * @param string &$outValue The stripped form of $value that can 

     *                          be used in PHP expressions

     * 

     * @return boolean

     */

    public function validate($value, &$outValue)

    {

        //1. The datetime value present in the $filter option should have 

        //   'datetime' prefix.

        //2. Month and day should be two digit

        if (!preg_match("/^datetime\'(\d{4})-(\d{2})-(\d{2})((\s|T)([0-1][0-9]|2[0-4]):([0-5][0-9])(:([0-5][0-9])([Z])?)?)?\'$/", strval($value), $matches)

        ) {

            return false;

        } 



        //stripoff prefix, and quotes from both ends

        $value = trim($value, 'datetime\'');

        //Validate the date using PHP DateTime class

        if (!self::validateWithoutPreFix($value)) {

            return false;

        }

    

        $outValue = "'" . $value . "'";

        return true;

    }



    /**

     * Gets full name of this type in EDM namespace

     * Note: implementation of IType::getFullTypeName

     * 

     * @return string

     */

    public function getFullTypeName()

    {

        return 'Edm.DateTime';

    }



    /**

     * Converts the given string value to datetime type.     

     * Note: This function will not perfrom any conversion.

     * 

     * @param string $stringValue Value to convert.

     * 

     * @return string

     */

    public function convert($stringValue)

    {

        return $stringValue;     

    }



    /**

     * Convert the given value to a form that can be used in OData uri. 

     * Note: The calling function should not pass null value, as this 

     * function will not perform any check for nullability 

     * 

     * @param mixed $value Value to convert.

     * 

     * @return string

     */

    public function convertToOData($value)

    {

        return 'datetime\'' . urlencode($value) . '\'';

    }



    /**

     * Checks a value is valid datetime

     * 

     * @param string $dateTime value to validate. 

     * 

     * @return boolean

     */

    public static function validateWithoutPreFix($dateTime)

    {

        try {

                $dt = new \DateTime($dateTime, new \DateTimeZone('UTC'));

        } catch (\Exception $e) {

                return false;

        }

            

        return true;

    }



    /**

     * Gets year from datetime

     * 

     * @param string $dateTime datetime to get the year from

     * 

     * @return int

     */

    public static function year($dateTime)

    {

        $date = new \DateTime($dateTime);

        return $date->format("Y");

    }



    /**

     * Gets month from datetime

     * 

     * @param string $dateTime datetime to get the month from

     * 

     * @return int

     */

    public static function month($dateTime)

    {

        $date = new \DateTime($dateTime);

        return $date->format("m");

    }



    /**

     * Gets day from datetime

     * 

     * @param string $dateTime datetime to get the day from

     * 

     * @return int

     */

    public static function day($dateTime)

    {

        $date = new \DateTime($dateTime);

        return $date->format("d");

    }



    /**

     * Gets hour from datetime

     * 

     * @param string $dateTime datetime to get the hour from

     * 

     * @return int

     */

    public static function hour($dateTime)

    {

        $date = new \DateTime($dateTime);

        return $date->format("H");

    }



    /**

     * Gets minute from datetime

     * 

     * @param string $dateTime datetime to get the minute from

     * 

     * @return int

     */

    public static function minute($dateTime)

    {

        $date = new \DateTime($dateTime);

        return $date->format("i");

    }



    /**

     * Gets second from datetime

     * 

     * @param string $dateTime datetime to get the second from

     * 

     * @return int

     */

    public static function second($dateTime)

    {

        $date = new \DateTime($dateTime);

        return $date->format("s");

    }

    

    /**

     * Compare two dates. Note that this function will not perform any

     * validation on dates, one should use either validate or

     * validateWithoutPrefix to validate the date before calling this 

     * function

     * 

     * @param string $dateTime1 First date

     * @param string $dateTime2 Second date

     * 

     * @return int

     */

    public static function dateTimeCmp($dateTime1, $dateTime2)

    {

        return strtotime($dateTime1) - strtotime($dateTime2);

    }

}