Source for file json-encoder.php

<?php
/**
 *****************************************************
 * This module has been modified by ccHost developers *
 *****************************************************
 *
 * 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_Json
 * @copyright  Copyright (c) 2006 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
 
 
/**
 * Encode PHP constructs to JSON (modified for ccHost)
 *
 * @package    core
 * @copyright  Copyright (c) 2006 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class CCZend_Json_Encoder
{
    /**
     * Array of visited objects; used to prevent cycling.
     *
     * @var array 
     */
    var $_visited = array();
 
    /**
     * Constructor
     */
    function __construct()
    {
    }
 
    /**
     * Use the JSON encoding scheme for the value specified
     *
     * @param mixed $value  value the object to be encoded
     * @return string  The encoded value
     */
    function encode($value)
    {
        $encoder = new CCZend_Json_Encoder();
 
        return $encoder->_encodeValue($value);
    }
 
    /**
     * Recursive driver which determines the type of value to be encoded
     * and then dispatches to the appropriate method. $values are either
     *    - objects (returns from {@link _encodeObject()})
     *    - arrays (returns from {@link _encodeArray()})
     *    - basic datums (e.g. numbers or strings) (returns from {@link _encodeDatum()})
     *
     * @param $value mixed The value to be encoded
     * @return string Encoded value
     */
    function _encodeValue(&$value)
    {
        if (is_object($value)) {
            return $this->_encodeObject($value);
        } else if (is_array($value)) {
            return $this->_encodeArray($value);
        }
 
        return $this->_encodeDatum($value);
    }
 
 
 
    /**
     * Encode an object to JSON by encoding each of the properties
     *
     * A special property is added to the JSON object called '__className'
     * that contains the name of the class of $value. This is used to decode
     * the object on the client into a specific class.
     *
     * @param $value object
     * @return string 
     */
    function _encodeObject(&$value)
    {
        if ($this->_wasVisited($value)) {
            trigger_error(
                'Cycles not supported in JSON encoding, cycle introduced by '
                . 'class "' . get_class($value) . '"'
            );
        }
 
        $this->_visited[] = $value;
 
        $props = '';
        foreach (get_object_vars($value) as $name => $propValue) {
            if (isset($propValue)) {
                $props .= ', '
                        . $this->_encodeValue($name)
                        . ' : '
                        . $this->_encodeValue($propValue);
            }
        }
 
        return '{' . '"__className": "' . get_class($value) . '"'
                . $props . '}';
    }
 
 
    /**
     * Determine if an object has been serialized already
     *
     * @access protected
     * @param mixed $value 
     * @return boolean 
     */
    function _wasVisited(&$value)
    {
        if (in_array($value, $this->_visited, true)) {
            return true;
        }
 
        return false;
    }
 
 
    /**
     * JSON encode an array value
     *
     * Recursively encodes each value of an array and returns a JSON encoded
     * array string.
     *
     * Arrays are defined as integer-indexed arrays starting at index 0, where
     * the last index is (count($array) -1); any deviation from that is
     * considered an associative array, and will be encoded as such.
     *
     * @param $array array
     * @return string 
     */
    function _encodeArray(&$array)
    {
        $tmpArray = array();
 
        // Check for associative array
        if (array_keys($array) !== range(0, count($array) - 1)) {
            // Associative array
            $result = '{';
            foreach ($array as $key => $value) {
                $key = (string) $key;
                $tmpArray[] = $this->_encodeString($key)
                            . ' : '
                            . $this->_encodeValue($value);
            }
            $result .= implode(', ', $tmpArray);
            $result .= '}';
        } else {
            // Indexed array
            $result = '[';
            $length = count($array);
            for ($i = 0; $i < $length; $i++) {
                $tmpArray[] = $this->_encodeValue($array[$i]);
            }
            $result .= implode(', ', $tmpArray);
            $result .= ']';
        }
 
        return $result;
    }
 
 
    /**
     * JSON encode a basic data type (string, number, boolean, null)
     *
     * If value type is not a string, number, boolean, or null, the string
     * 'null' is returned.
     *
     * @param $value mixed
     * @return string 
     */
    function _encodeDatum(&$value)
    {
        $result = 'null';
 
        if (is_numeric($value)) {
            $result = (string)$value;
        } elseif (is_string($value)) {
            $result = $this->_encodeString($value);
        } elseif (is_bool($value)) {
            $result = $value ? 'true' : 'false';
        }
 
        return $result;
    }
 
 
    /**
     * JSON encode a string value by escaping characters as necessary
     *
     * @param $value string
     * @return string 
     */
    function _encodeString(&$string)
    {
        // Escape these characters with a backslash:
        // " \ / \n \r \t \b \f
        $search  = array('\\', "\n", "\t", "\r", "\b", "\f", '"');
        $replace = array('\\\\', '\\n', '\\t', '\\r', '\\b', '\\f', '\"');
        $string  = str_replace($search, $replace, $string);
 
        // Escape certain ASCII characters:
        // 0x08 => \b
        // 0x0c => \f
        $string = str_replace(array(chr(0x08), chr(0x0C)), array('\b', '\f'), $string);
 
        return '"' . $string . '"';
    }
 
}