/modules/gplusone/JSON.php

<?php

/*

***************************************************************************

*   Copyright (C) 2007 by Cesar D. Rodas                                  *

*   crodas@phpy.org                                                       *

*                                                                         *

*   Permission is hereby granted, free of charge, to any person obtaining *

*   a copy of this software and associated documentation files (the       *

*   "Software"), to deal in the Software without restriction, including   *

*   without limitation the rights to use, copy, modify, merge, publish,   *

*   distribute, sublicense, and/or sell copies of the Software, and to    *

*   permit persons to whom the Software is furnished to do so, subject to *

*   the following conditions:                                             *

*                                                                         *

*   The above copyright notice and this permission notice shall be        *

*   included in all copies or substantial portions of the Software.       *

*                                                                         *

*   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       *

*   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    *

*   MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*

*   IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR     *

*   OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, *

*   ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR *

*   OTHER DEALINGS IN THE SOFTWARE.                                       *

***************************************************************************

*/



/**

 *    Serialize and Unserialize PHP Objects and array

 *    into JSON notation. 

 *

 *    @category   Javascript

 *    @package    JSON

 *    @author     Cesar D. Rodas <crodas@phpy.org>

 *    @copyright  2007 Cesar D. Rodas

 *    @license    http://www.opensource.org/licenses/bsd-license.php  BSD License

 *    @version    1.0

 *    @link       http://cesars.users.phpclasses.org/json 

 */



define('IN_NOWHERE',0);

define('IN_STRING',1);

define('IN_OBJECT',2);

define('IN_ATOMIC',3);

define('IN_ASSIGN',4);

define('IN_ENDSTMT',5);

define('IN_ARRAY',6);



/**

 *  JSON

 *

 *    This class serilize an PHP OBJECT or an ARRAY into JSON

 *    notation. Also convert a JSON text into a PHP OBJECT or

 *    array.

 *

 *    @category   Javascript

 *    @package    JSON

 *    @author     Cesar D. Rodas <crodas@phpy.org>

 *    @copyright  2007 Cesar D. Rodas

 *    @license    http://www.opensource.org/licenses/bsd-license.php  BSD License

 *    @version    1.0

 *    @link       http://cesars.users.phpclasses.org/json 

 */

class JSON

{

     /**

     *    Was parsed with an error?

     *    

     *    var bool

     *    @access private

     */

    var $error;

    

    function Json() {

        $this->error = false;

    }

    

    /**

     *    Serialize

     *

     *    Serialize a PHP OBJECT or an ARRAY into 

     *    JSON notation.

     *

     *    param mixed $obj Object or array to serialize

     *    return string JSON.

     */

    function serialize($obj) {

        if ( is_object($obj) ) {

            $e = get_object_vars($obj);

            /* bug reported by Ben Rowe */

            /* Adding default empty array if the */

            /* object doesn't have any property */

            $properties = array();

            foreach ($e as $k => $v) {

                $properties[] = $this->_serialize( $k,$v );

            }

            return "{".implode(",",$properties)."}";

        } else if ( is_array($obj) ) {

            return $this->_serialize('',$obj);

        }

    }

    

    /**

     *    UnSerialize

     *

     *    Transform an JSON text into a PHP object

     *    and return it.

     *    @access public 

     *    @param string $text JSON text

     *    @return mixed PHP Object, array or false.

     */

    function unserialize( $text ) {

        $this->error = false;

        

        return !$this->error ? $this->_unserialize($text) : false;

    }

    

    /**

     *    UnSerialize

     *

     *    Transform an JSON text into a PHP object

     *    and return it.

     *    @access private 

     *    @param string $text JSON text

     *    @return mixed PHP Object, array or false.

     */

    function _unserialize($text) {

        $ret = new stdClass;

         

        while (  $f = $this->getNextToken($text,$i,$type)  ) {

            switch ( $type ) {

                case IN_ARRAY:

                    $tmp = $this->_unserializeArray($text);

                    $ret = $tmp[0];

                    break;

                case IN_OBJECT:

                    $g=0;

                    do  {

                        $varName = $this->getNextToken($f,$g,$xType);

                        if ( $xType != IN_STRING )  {

                            return false; /* error parsing */

                        }

                        $this->getNextToken($f,$g,$xType);

                        if ( $xType != IN_ASSIGN) return false;

                        $value = $this->getNextToken($f,$g,$xType);

                        

                        if ( $xType == IN_OBJECT) {

                            $ret->$varName = $this->unserialize( "{".$value."}" );

                            $g--;

                        } else if ($xType == IN_ARRAY) {

                            $ret->$varName = $this->_unserializeArray( $value);

                            $g--;

                        } else

                            $ret->$varName = $value;

                        

                        $this->getNextToken($f,$g,$xType);

                    } while ( $xType == IN_ENDSTMT);

                    break;

                default:

                    $this->error = true;

                    break 2;

            }

        }

        return $ret;

    }

    

    /**

     *    JSON Array Parser

     *

     *    This method transform an json-array into a PHP 

     *    array

     *    @access private

     *    @param string $text String to parse

     *    @return Array PHP Array

     */

    function _unserializeArray($text) {

        $r = array();

        do {

            $f = $this->getNextToken($text,$i,$type);

            $f = preg_replace_callback('/\\\u[a-z0-9]{4}/',create_function('$m','return chr(base_convert($m[0],16,10));'),$f);

            switch ( $type ) {

                case IN_STRING:

                case IN_ATOMIC:

                    $r[] = $f;

                    break;

                case IN_OBJECT:

                    $r[] = $this->unserialize("{".$f."}");

                    $i--;

                    break;

                case IN_ARRAY: 

                    $r[] = $this->_unserializeArray($f);

                    $i--;

                    break;

                    

            }

            $this->getNextToken($text,$i,$type);

        } while ( $type == IN_ENDSTMT);

        

        return $r;

    }

    

    /**

     *  Tokenizer

     *

     *  Return to the Parser the next valid token and the type     

     *  of the token. If the tokenizer fails it returns false.

     *    

     *    @access private

     *  @param string $e Text to extract token

     *  @param integer $i  Start position to search next token

     *  @param integer $state Variable to get the token type

     *  @return string|bool Token in string or false on error.

     */

    function getNextToken($e, &$i, &$state) {

        $state = IN_NOWHERE;

        $end = -1;

        $start = -1;

        while ( $i < strlen($e) && $end == -1 ) {

            switch( $e[$i] ) {

                /* objects */

                case "{":

                case "[":

                    $_tag = $e[$i]; 

                    $_endtag = $_tag == "{" ? "}" : "]";

                    if ( $state == IN_NOWHERE ) {

                        $start = $i+1;

                        switch ($state) {

                            case IN_NOWHERE:

                                $aux = 1; /* for loop objects */

                                $state = $_tag == "{" ? IN_OBJECT : IN_ARRAY;

                                break;

                            default:

                                break 2; /* exit from switch and while */

                        }

                        while ( ++$i && $i < strlen($e) && $aux != 0 ) {

                            switch( $e[$i] ) {

                                case $_tag:

                                    $aux++;

                                    break;

                                case $_endtag:

                                    $aux--;

                                    break;

                            }

                        }

                        $end = $i-1;

                    }

                    break;

                

                case '"':

                case "'":

                    $state = IN_STRING;

                    $buf = "";

                    while ( ++$i && $i < strlen($e) && $e[$i] != '"' ) {

                        if ( $e[$i] == "\\") 

                            $i++;

                        $buf .= $e[$i];

                    }

                    $i++;

                    return eval('return "'.str_replace('"','\"',$buf).'";');

                    break;

                case ":":

                    $state = IN_ASSIGN;

                    $end = 1;

                    break;

                case "n":

                    if ( substr($e,$i,4) == "null" ) {

                        $i=$i+4;

                        $state = IN_ATOMIC;

                        return NULL;

                    }

                    else break 2; /* exit from switch and while */

                case "t":

                    if ( substr($e,$i,4) == "true") {

                        $state = IN_ATOMIC;

                        $i=$i+4;

                        return true;

                    }else break 2; /* exit from switch and while */

                    break;

                case "f":

                    if ( substr($e,$i,4) == "false") {

                        $state = IN_ATOMIC;

                        $i=$i+4;

                        return false;

                    }

                    else break 2; /* exit from switch and while */

                    break;    

                case ",":

                    $state = IN_ENDSTMT;

                    $end = 1;

                    break;

                case " ":

                case "\t":

                case "\r":

                case "\n":

                    break;

                case "+":

                case "-":

                case 0:

                case 1:

                case 2:

                case 3:

                case 4:

                case 5:

                case 6:

                case 7:

                case 8:

                case 9:

                case '.':

                    $state = IN_ATOMIC;

                    $start = (int)$i;

                    if ( $e[$i] == "-" || $e[$i] == "+")

                        $i++;

                    for ( ;  $i < strlen($e) && (is_numeric($e[$i]) || $e[$i] == "." || strtolower($e[$i]) == "e") ;$i++){

                        $n = $i+1 < strlen($e) ? $e[$i+1] : "";

                        $a = strtolower($e[$i]);

                        if ( $a == "e" && ($n == "+" || $n == "-"))

                            $i++;

                        else if ( $a == "e") 

                            $this->error=true;

                    }

                    

                    $end = $i;

                    break 2; /* break while too */

                default: 

                    $this->error = true;

                    

            }

            $i++;

        }

        

        return $start == -1 || $end == -1 ? false : substr($e, $start, $end - $start);

    }

    

    /** 

     *    Internal Serializer

     *

     *    @param string $key Variable name

     *    @param mixed $value Value of the variable

     *    @access private

     *    @return string Serialized variable

     */

    function _serialize (  $key = '', &$value ) {

        $r = '';

        if ( $key != '')$r .= "\"${key}\" : ";

        if ( is_numeric($value) ) {

            $r .= ''.$value.'';

        } else if ( is_string($value) ) {

            $r .= '"'.$this->toString($value).'"';

        } else if ( is_object($value) ) {

            $r .= $this->serialize($value);

        } else if ( is_null($value) ) {

            $r .= "null";

        } else if ( is_bool($value) ) {

            $r .= $value ? "true":"false";

        } else if ( is_array($value) ) {

            foreach($value as $k => $v)

                $f[] = $this->_serialize('',$v);

            $r .= "[".implode(",",$f)."]";

            unset($f);

        }

        return $r;

    }

    

    /** 

     *    Convert String variables

     *

     *    @param string $e Variable with an string value

     *    @access private

     *    @return string Serialized variable

     */

    function toString($e) {

        $rep = array("\\","\r","\n","\t","'",'"');

        $val = array("\\\\",'\r','\n','\t','\'','\"');

        $e = str_replace($rep, $val, $e);

        return $e;

    }

}

?>