<?php

if(!defined('XAPP_JSON_CLASS')){


    /**
     * Converts to and from JSON format.
     *
     * JSON (JavaScript Object Notation) is a lightweight data-interchange
     * format. It is easy for humans to read and write. It is easy for machines
     * to parse and generate. It is based on a subset of the JavaScript
     * Programming Language, Standard ECMA-262 3rd Edition - December 1999.
     * This feature can also be found in  Python. JSON is a text format that is
     * completely language independent but uses conventions that are familiar
     * to programmers of the C-family of languages, including C, C++, C#, Java,
     * JavaScript, Perl, TCL, and many others. These properties make JSON an
     * ideal data-interchange language.
     *
     * This package provides a simple encoder and decoder for JSON notation. It
     * is intended for use with client-side Javascript applications that make
     * use of HTTPRequest to perform server communication functions - data can
     * be encoded into JSON notation for use in a client-side javascript, or
     * decoded from incoming Javascript requests. JSON format is native to
     * Javascript, and can be directly eval()'ed with no further parsing
     *
     * overhead
     *
     * All strings should be in ASCII or UTF-8 format!
     *
     *
     * LICENSE: Redistribution and use in source and binary forms, with or
     * without modification, are permitted provided that the following
     * conditions are met: Redistributions of source code must retain the
     * above copyright notice, this list of conditions and the following
     * disclaimer. Redistributions in binary form must reproduce the above
     * copyright notice, this list of conditions and the following disclaimer
     * in the documentation and/or other materials provided with the
     * distribution.
     *
     * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
     * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
     * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
     * NO EVENT SHALL CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
     * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
     * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
     * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
     * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
     * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
     * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
     * DAMAGE.
     *
     * @category
     * @package     JSON
     * @author      Michal Migurski <mike-json@teczno.com>
     * @author      Matt Knapp <mdknapp[at]gmail[dot]com>
     * @author      xapp-Studio
     * @author      Brett Stimmerman <brettstimmerman[at]gmail[dot]com>
     * @copyright   2005 Michal Migurski
     * @version     CVS: $Id$
     * @license :   GPL v2. http://www.gnu.org/licenses/gpl-2.0.html
     * @link        http://pear.php.net/pepr/pepr-proposal-show.php?id=198
     */

    /**
     * Marker constant for Services_JSON::decode(), used to flag stack state
     */
    define('SERVICES_JSON_SLICE',   1);

    /**
     * Marker constant for Services_JSON::decode(), used to flag stack state
     */
    define('SERVICES_JSON_IN_STR',  2);
    /**
     * Marker constant for Services_JSON::decode(), used to flag stack state
     */
    define('SERVICES_JSON_IN_ARR',  3);
    /**
     * Marker constant for Services_JSON::decode(), used to flag stack state
     */
    define('SERVICES_JSON_IN_OBJ',  4);
    /**
     * Marker constant for Services_JSON::decode(), used to flag stack state
     */
    define('SERVICES_JSON_IN_CMT', 5);

    /**
     * Behavior switch for Services_JSON::decode()
     */
    define('SERVICES_JSON_LOOSE_TYPE', 16);

    /**
     * Behavior switch for Services_JSON::decode()
     */
    define('SERVICES_JSON_SUPPRESS_ERRORS', 32);

    /**
     * Behavior switch for Services_JSON::decode()
     */
    define('SERVICES_JSON_USE_TO_JSON', 64);

    /**
     * Converts to and from JSON format.
     *
     * Brief example of use:
     *
     * <code>
     * // create a new instance of Services_JSON
     * $json = new Services_JSON();
     *
     * // convert a complexe value to JSON notation, and send it to the browser
     * $value = array('foo', 'bar', array(1, 2, 'baz'), array(3, array(4)));
     * $output = $json->encode($value);
     *
     * print($output);
     * // prints: ["foo","bar",[1,2,"baz"],[3,[4]]]
     *
     * // accept incoming POST data, assumed to be in JSON notation
     * $input = file_get_contents('php://input', 1000000);
     * $value = $json->decode($input);
     * </code>
     */
    if(!class_exists('Services_JSON')){

        class Services_JSON

        {
           /**
            * constructs a new JSON instance
            *
            * @param    int     $use    object behavior flags; combine with boolean-OR
            *
            *                           possible values:
            *                           - SERVICES_JSON_LOOSE_TYPE:  loose typing.
            *                                   "{...}" syntax creates associative arrays
            *                                   instead of objects in decode().
            *                           - SERVICES_JSON_SUPPRESS_ERRORS:  error suppression.
            *                                   Values which can't be encoded (e.g. resources)
            *                                   appear as NULL instead of throwing errors.
            *                                   By default, a deeply-nested resource will
            *                                   bubble up with an error, so all return values
            *                                   from encode() should be checked with isError()
            *                           - SERVICES_JSON_USE_TO_JSON:  call toJSON when serializing objects
            *                                   It serializes the return value from the toJSON call rather
            *                                   than the object it'self,  toJSON can return associative arrays,
            *                                   strings or numbers, if you return an object, make sure it does
            *                                   not have a toJSON method, otherwise an error will occur.
            */
            function Services_JSON($use = 0)
            {
                $this->use = $use;
                $this->_mb_strlen            = function_exists('mb_strlen');
                $this->_mb_convert_encoding  = function_exists('mb_convert_encoding');
                $this->_mb_substr            = function_exists('mb_substr');
            }
            // private - cache the mbstring lookup results..
            var $_mb_strlen = false;
            var $_mb_substr = false;
            var $_mb_convert_encoding = false;

            // tab and crlf are used by stringfy to produce pretty JSON.
            var $_tab = '';
            var $_crlf = '';
            var $_indent = 0;
           /**
            * convert a string from one UTF-16 char to one UTF-8 char
            *
            * Normally should be handled by mb_convert_encoding, but
            * provides a slower PHP-only method for installations
            * that lack the multibye string extension.
            *
            * @param    string  $utf16  UTF-16 character
            * @return   string  UTF-8 character
            * @access   private
            */
            function utf162utf8($utf16)
            {
                // oh please oh please oh please oh please oh please
                if($this->_mb_convert_encoding) {
                    return mb_convert_encoding($utf16, 'UTF-8', 'UTF-16');
                }

                $bytes = (ord($utf16{0}) << 8) | ord($utf16{1});

                switch(true) {
                    case ((0x7F & $bytes) == $bytes):
                        // this case should never be reached, because we are in ASCII range
                        // see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
                        return chr(0x7F & $bytes);

                    case (0x07FF & $bytes) == $bytes:
                        // return a 2-byte UTF-8 character
                        // see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
                        return chr(0xC0 | (($bytes >> 6) & 0x1F))
                             . chr(0x80 | ($bytes & 0x3F));

                    case (0xFFFF & $bytes) == $bytes:
                        // return a 3-byte UTF-8 character
                        // see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
                        return chr(0xE0 | (($bytes >> 12) & 0x0F))
                             . chr(0x80 | (($bytes >> 6) & 0x3F))
                             . chr(0x80 | ($bytes & 0x3F));
                }

                // ignoring UTF-32 for now, sorry
                return '';
            }

           /**
            * convert a string from one UTF-8 char to one UTF-16 char
            *
            * Normally should be handled by mb_convert_encoding, but
            * provides a slower PHP-only method for installations
            * that lack the multibye string extension.
            *
            * @param    string  $utf8   UTF-8 character
            * @return   string  UTF-16 character
            * @access   private
            */
            function utf82utf16($utf8)
            {
                // oh please oh please oh please oh please oh please
                if($this->_mb_convert_encoding) {
                    return mb_convert_encoding($utf8, 'UTF-16', 'UTF-8');
                }

                switch($this->strlen8($utf8)) {
                    case 1:
                        // this case should never be reached, because we are in ASCII range
                        // see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
                        return $utf8;

                    case 2:
                        // return a UTF-16 character from a 2-byte UTF-8 char
                        // see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
                        return chr(0x07 & (ord($utf8{0}) >> 2))
                             . chr((0xC0 & (ord($utf8{0}) << 6))
                                 | (0x3F & ord($utf8{1})));

                    case 3:
                        // return a UTF-16 character from a 3-byte UTF-8 char
                        // see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
                        return chr((0xF0 & (ord($utf8{0}) << 4))
                                 | (0x0F & (ord($utf8{1}) >> 2)))
                             . chr((0xC0 & (ord($utf8{1}) << 6))
                                 | (0x7F & ord($utf8{2})));
                }

                // ignoring UTF-32 for now, sorry
                return '';
            }

             /**
            * stringfy an arbitrary variable into JSON format (and sends JSON Header)
            *
            * @param    mixed   $var    any number, boolean, string, array, or object to be encoded.
            *                           see argument 1 to Services_JSON() above for array-parsing behavior.
            *                           if var is a strng, note that encode() always expects it
            *                           to be in ASCII or UTF-8 format!
            *
            * @return   mixed   JSON string representation of input var or an error if a problem occurs
            * @access   public
            */
           /**
            * encodes an arbitrary variable into JSON format (and sends JSON Header)
            * UNSAFE - does not send HTTP headers (to be compatible with Javsacript Spec)
            *
            * @param    mixed   $var    any number, boolean, string, array, or object to be encoded.
            *                           see argument 1 to Services_JSON() above for array-parsing behavior.
            *                           if var is a strng, note that encode() always expects it
            *                           to be in ASCII or UTF-8 format!
            * @param    mixed   $replacer    NOT SUPPORTED YET.
            * @param    number|string   $space
            *                           an optional parameter that specifies the indentation
            *                           of nested structures. If it is omitted, the text will
            *                           be packed without extra whitespace. If it is a number,
            *                           it will specify the number of spaces to indent at each
            *                           level. If it is a string (such as '\t' or '&nbsp;'),
            *                           it contains the characters used to indent at each level.
            *
            * @return   mixed   JSON string representation of input var or an error if a problem occurs
            * @access   public
            */
            static function stringify($var, $replacer=false, $space=false)
            {
                //header('Content-type: application/json');
                $s = new Services_JSON(SERVICES_JSON_USE_TO_JSON);

                $s->_tab = is_numeric($space) ? str_repeat(' ', $space) : $space;
                $s->_crlf = "\n";
                $s->_indent = 0;
                return  $s->encodeUnsafe($var);

            }
            /**
            * encodes an arbitrary variable into JSON format (and sends JSON Header)
            *
            * @param    mixed   $var    any number, boolean, string, array, or object to be encoded.
            *                           see argument 1 to Services_JSON() above for array-parsing behavior.
            *                           if var is a strng, note that encode() always expects it
            *                           to be in ASCII or UTF-8 format!
            *
            * @return   mixed   JSON string representation of input var or an error if a problem occurs
            * @access   public
            */
            function encode($var)
            {
                header('Content-type: application/json');
                return $this->encodeUnsafe($var);
            }
            /**
            * encodes an arbitrary variable into JSON format without JSON Header - warning - may allow XSS!!!!)
            *
            * @param    mixed   $var    any number, boolean, string, array, or object to be encoded.
            *                           see argument 1 to Services_JSON() above for array-parsing behavior.
            *                           if var is a strng, note that encode() always expects it
            *                           to be in ASCII or UTF-8 format!
            *
            * @return   mixed   JSON string representation of input var or an error if a problem occurs
            * @access   public
            */
            function encodeUnsafe($var)
            {
                // see bug #16908 - regarding numeric locale printing
                $lc = setlocale(LC_NUMERIC, 0);
                setlocale(LC_NUMERIC, 'C');
                $ret = $this->_encode($var);
                setlocale(LC_NUMERIC, $lc);
                return $ret;

            }
            /**
            * PRIVATE CODE that does the work of encodes an arbitrary variable into JSON format
            *
            * @param    mixed   $var    any number, boolean, string, array, or object to be encoded.
            *                           see argument 1 to Services_JSON() above for array-parsing behavior.
            *                           if var is a strng, note that encode() always expects it
            *                           to be in ASCII or UTF-8 format!
            *
            * @return   mixed   JSON string representation of input var or an error if a problem occurs
            * @access   public
            */
            function _encode($var)
            {
                $ind = str_repeat($this->_tab, $this->_indent);
                $indx = $ind . $this->_tab;

                switch (gettype($var)) {
                    case 'boolean':
                        return $var ? 'true' : 'false';

                    case 'NULL':
                        return 'null';

                    case 'integer':
                        return (int) $var;

                    case 'double':
                    case 'float':
                        return  (float) $var;

                    case 'string':
                        // STRINGS ARE EXPECTED TO BE IN ASCII OR UTF-8 FORMAT
                        $ascii = '';
                        $strlen_var = $this->strlen8($var);

                       /*
                        * Iterate over every character in the string,
                        * escaping with a slash or encoding to UTF-8 where necessary
                        */
                        for ($c = 0; $c < $strlen_var; ++$c) {

                            $ord_var_c = ord($var{$c});

                            switch (true) {
                                case $ord_var_c == 0x08:
                                    $ascii .= '\b';
                                    break;
                                case $ord_var_c == 0x09:
                                    $ascii .= '\t';
                                    break;
                                case $ord_var_c == 0x0A:
                                    $ascii .= '\n';
                                    break;
                                case $ord_var_c == 0x0C:
                                    $ascii .= '\f';
                                    break;
                                case $ord_var_c == 0x0D:
                                    $ascii .= '\r';
                                    break;

                                case $ord_var_c == 0x22:
                                case $ord_var_c == 0x2F:
                                case $ord_var_c == 0x5C:
                                    // double quote, slash, slosh
                                    $ascii .= '\\'.$var{$c};
                                    break;

                                case (($ord_var_c >= 0x20) && ($ord_var_c <= 0x7F)):
                                    // characters U-00000000 - U-0000007F (same as ASCII)
                                    $ascii .= $var{$c};
                                    break;

                                case (($ord_var_c & 0xE0) == 0xC0):
                                    // characters U-00000080 - U-000007FF, mask 110XXXXX
                                    // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
                                    if ($c+1 >= $strlen_var) {
                                        $c += 1;
                                        $ascii .= '?';
                                        break;
                                    }

                                    $char = pack('C*', $ord_var_c, ord($var{$c + 1}));
                                    $c += 1;
                                    $utf16 = $this->utf82utf16($char);
                                    $ascii .= sprintf('\u%04s', bin2hex($utf16));
                                    break;

                                case (($ord_var_c & 0xF0) == 0xE0):
                                    if ($c+2 >= $strlen_var) {
                                        $c += 2;
                                        $ascii .= '?';
                                        break;
                                    }
                                    // characters U-00000800 - U-0000FFFF, mask 1110XXXX
                                    // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
                                    $char = pack('C*', $ord_var_c,
                                                 @ord($var{$c + 1}),
                                                 @ord($var{$c + 2}));
                                    $c += 2;
                                    $utf16 = $this->utf82utf16($char);
                                    $ascii .= sprintf('\u%04s', bin2hex($utf16));
                                    break;

                                case (($ord_var_c & 0xF8) == 0xF0):
                                    if ($c+3 >= $strlen_var) {
                                        $c += 3;
                                        $ascii .= '?';
                                        break;
                                    }
                                    // characters U-00010000 - U-001FFFFF, mask 11110XXX
                                    // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
                                    $char = pack('C*', $ord_var_c,
                                                 ord($var{$c + 1}),
                                                 ord($var{$c + 2}),
                                                 ord($var{$c + 3}));
                                    $c += 3;
                                    $utf16 = $this->utf82utf16($char);
                                    $ascii .= sprintf('\u%04s', bin2hex($utf16));
                                    break;

                                case (($ord_var_c & 0xFC) == 0xF8):
                                    // characters U-00200000 - U-03FFFFFF, mask 111110XX
                                    // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
                                    if ($c+4 >= $strlen_var) {
                                        $c += 4;
                                        $ascii .= '?';
                                        break;
                                    }
                                    $char = pack('C*', $ord_var_c,
                                                 ord($var{$c + 1}),
                                                 ord($var{$c + 2}),
                                                 ord($var{$c + 3}),
                                                 ord($var{$c + 4}));
                                    $c += 4;
                                    $utf16 = $this->utf82utf16($char);
                                    $ascii .= sprintf('\u%04s', bin2hex($utf16));
                                    break;

                                case (($ord_var_c & 0xFE) == 0xFC):
                                if ($c+5 >= $strlen_var) {
                                        $c += 5;
                                        $ascii .= '?';
                                        break;
                                    }
                                    // characters U-04000000 - U-7FFFFFFF, mask 1111110X
                                    // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
                                    $char = pack('C*', $ord_var_c,
                                                 ord($var{$c + 1}),
                                                 ord($var{$c + 2}),
                                                 ord($var{$c + 3}),
                                                 ord($var{$c + 4}),
                                                 ord($var{$c + 5}));
                                    $c += 5;
                                    $utf16 = $this->utf82utf16($char);
                                    $ascii .= sprintf('\u%04s', bin2hex($utf16));
                                    break;
                            }
                        }
                        return  '"'.$ascii.'"';

                    case 'array':
                       /*
                        * As per JSON spec if any array key is not an integer
                        * we must treat the the whole array as an object. We
                        * also try to catch a sparsely populated associative
                        * array with numeric keys here because some JS engines
                        * will create an array with empty indexes up to
                        * max_index which can cause memory issues and because
                        * the keys, which may be relevant, will be remapped
                        * otherwise.
                        *
                        * As per the ECMA and JSON specification an object may
                        * have any string as a property. Unfortunately due to
                        * a hole in the ECMA specification if the key is a
                        * ECMA reserved word or starts with a digit the
                        * parameter is only accessible using ECMAScript's
                        * bracket notation.
                        */

                        // treat as a JSON object
                        if (is_array($var) && count($var) && (array_keys($var) !== range(0, sizeof($var) - 1))) {
                            $this->_indent++;
                            $properties = array_map(array($this, 'name_value'),
                                                    array_keys($var),
                                                    array_values($var));
                            $this->_indent--;
                            foreach($properties as $property) {
                                if(Services_JSON::isError($property)) {
                                    return $property;
                                }
                            }

                            return "{" . $this->_crlf .  $indx .
                                join(",". $this->_crlf . $indx, $properties) . $this->_crlf .
                                $ind."}";

                        }

                        // treat it like a regular array
                        $this->_indent++;
                        $elements = array_map(array($this, '_encode'), $var);
                        $this->_indent--;

                        foreach($elements as $element) {
                            if(Services_JSON::isError($element)) {
                                return $element;
                            }
                        }

                        $pad = $this->_tab === '' ? '' : ' ';

                        // short array, just show it on one line.
                        if (strlen(join(',' . $pad, $elements)) < 30) {
                            return '[' . join(',' . $pad, $elements) . ']';
                        }

                        return "[" . $this->_crlf .
                            $indx .  join(",". $this->_crlf . $indx, $elements) . $this->_crlf .
                            $ind . "]";

                    case 'object':

                        // support toJSON methods.
                        if (($this->use & SERVICES_JSON_USE_TO_JSON) && method_exists($var, 'toJSON')) {
                            // this may end up allowing unlimited recursion
                            // so we check the return value to make sure it's not got the same method.
                            $recode = $var->toJSON();

                            if (method_exists($recode, 'toJSON')) {

                                return ($this->use & SERVICES_JSON_SUPPRESS_ERRORS)
                                ? 'null'
                                : new Services_JSON_Error(class_name($var).
                                    " toJSON returned an object with a toJSON method.");

                            }

                            return $this->_encode( $recode );
                        }

                        $vars = get_object_vars($var);

                        $this->_indent++;
                        $properties = array_map(array($this, 'name_value'),
                                                array_keys($vars),
                                                array_values($vars));
                        $this->_indent--;

                        foreach($properties as $property) {
                            if(Services_JSON::isError($property)) {
                                return $property;
                            }
                        }

                        return "{" . $this->_crlf .
                            $indx .  join(",". $this->_crlf . $indx, $properties) . $this->_crlf .
                            $ind . "}";

                    default:
                        return ($this->use & SERVICES_JSON_SUPPRESS_ERRORS)
                            ? 'null'
                            : new Services_JSON_Error(gettype($var)." can not be encoded as JSON string");
                }
            }

           /**
            * array-walking function for use in generating JSON-formatted name-value pairs
            *
            * @param    string  $name   name of key to use
            * @param    mixed   $value  reference to an array element to be encoded
            *
            * @return   string  JSON-formatted name-value pair, like '"name":value'
            * @access   private
            */
            function name_value($name, $value)
            {
                $encoded_value = $this->_encode($value);

                if(Services_JSON::isError($encoded_value)) {
                    return $encoded_value;
                }

                $pad = $this->_tab === '' ? '' : ' ';

                return $this->_encode(strval($name)) . $pad . ':' . $pad . $encoded_value;
            }

           /**
            * reduce a string by removing leading and trailing comments and whitespace
            *
            * @param    $str    string      string value to strip of comments and whitespace
            *
            * @return   string  string value stripped of comments and whitespace
            * @access   private
            */
            function reduce_string($str)
            {
                $str = preg_replace(array(

                        // eliminate single line comments in '// ...' form
                        '#^\s*//(.+)$#m',

                        // eliminate multi-line comments in '/* ... */' form, at start of string
                        '#^\s*/\*(.+)\*/#Us',

                        // eliminate multi-line comments in '/* ... */' form, at end of string
                        '#/\*(.+)\*/\s*$#Us'

                    ), '', $str);

                // eliminate extraneous space
                return trim($str);
            }

           /**
            * decodes a JSON string into appropriate variable
            *
            * @param    string  $str    JSON-formatted string
            *
            * @return   mixed   number, boolean, string, array, or object
            *                   corresponding to given JSON input string.
            *                   See argument 1 to Services_JSON() above for object-output behavior.
            *                   Note that decode() always returns strings
            *                   in ASCII or UTF-8 format!
            * @access   public
            */
            function decode($str)
            {
                $str = $this->reduce_string($str);

                switch (strtolower($str)) {
                    case 'true':
                        return true;

                    case 'false':
                        return false;

                    case 'null':
                        return null;

                    default:
                        $m = array();

                        if (is_numeric($str)) {
                            // Lookie-loo, it's a number

                            // This would work on its own, but I'm trying to be
                            // good about returning integers where appropriate:
                            // return (float)$str;

                            // Return float or int, as appropriate
                            return ((float)$str == (integer)$str)
                                ? (integer)$str
                                : (float)$str;

                        } elseif (preg_match('/^("|\').*(\1)$/s', $str, $m) && $m[1] == $m[2]) {
                            // STRINGS RETURNED IN UTF-8 FORMAT
                            $delim = $this->substr8($str, 0, 1);
                            $chrs = $this->substr8($str, 1, -1);
                            $utf8 = '';
                            $strlen_chrs = $this->strlen8($chrs);

                            for ($c = 0; $c < $strlen_chrs; ++$c) {

                                $substr_chrs_c_2 = $this->substr8($chrs, $c, 2);
                                $ord_chrs_c = ord($chrs{$c});

                                switch (true) {
                                    case $substr_chrs_c_2 == '\b':
                                        $utf8 .= chr(0x08);
                                        ++$c;
                                        break;
                                    case $substr_chrs_c_2 == '\t':
                                        $utf8 .= chr(0x09);
                                        ++$c;
                                        break;
                                    case $substr_chrs_c_2 == '\n':
                                        $utf8 .= chr(0x0A);
                                        ++$c;
                                        break;
                                    case $substr_chrs_c_2 == '\f':
                                        $utf8 .= chr(0x0C);
                                        ++$c;
                                        break;
                                    case $substr_chrs_c_2 == '\r':
                                        $utf8 .= chr(0x0D);
                                        ++$c;
                                        break;

                                    case $substr_chrs_c_2 == '\\"':
                                    case $substr_chrs_c_2 == '\\\'':
                                    case $substr_chrs_c_2 == '\\\\':
                                    case $substr_chrs_c_2 == '\\/':
                                        if (($delim == '"' && $substr_chrs_c_2 != '\\\'') ||
                                           ($delim == "'" && $substr_chrs_c_2 != '\\"')) {
                                            $utf8 .= $chrs{++$c};
                                        }
                                        break;

                                    case preg_match('/\\\u[0-9A-F]{4}/i', $this->substr8($chrs, $c, 6)):
                                        // single, escaped unicode character
                                        $utf16 = chr(hexdec($this->substr8($chrs, ($c + 2), 2)))
                                               . chr(hexdec($this->substr8($chrs, ($c + 4), 2)));
                                        $utf8 .= $this->utf162utf8($utf16);
                                        $c += 5;
                                        break;

                                    case ($ord_chrs_c >= 0x20) && ($ord_chrs_c <= 0x7F):
                                        $utf8 .= $chrs{$c};
                                        break;

                                    case ($ord_chrs_c & 0xE0) == 0xC0:
                                        // characters U-00000080 - U-000007FF, mask 110XXXXX
                                        //see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
                                        $utf8 .= $this->substr8($chrs, $c, 2);
                                        ++$c;
                                        break;

                                    case ($ord_chrs_c & 0xF0) == 0xE0:
                                        // characters U-00000800 - U-0000FFFF, mask 1110XXXX
                                        // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
                                        $utf8 .= $this->substr8($chrs, $c, 3);
                                        $c += 2;
                                        break;

                                    case ($ord_chrs_c & 0xF8) == 0xF0:
                                        // characters U-00010000 - U-001FFFFF, mask 11110XXX
                                        // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
                                        $utf8 .= $this->substr8($chrs, $c, 4);
                                        $c += 3;
                                        break;

                                    case ($ord_chrs_c & 0xFC) == 0xF8:
                                        // characters U-00200000 - U-03FFFFFF, mask 111110XX
                                        // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
                                        $utf8 .= $this->substr8($chrs, $c, 5);
                                        $c += 4;
                                        break;

                                    case ($ord_chrs_c & 0xFE) == 0xFC:
                                        // characters U-04000000 - U-7FFFFFFF, mask 1111110X
                                        // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
                                        $utf8 .= $this->substr8($chrs, $c, 6);
                                        $c += 5;
                                        break;

                                }

                            }

                            return $utf8;

                        } elseif (preg_match('/^\[.*\]$/s', $str) || preg_match('/^\{.*\}$/s', $str)) {
                            // array, or object notation

                            if ($str{0} == '[') {
                                $stk = array(SERVICES_JSON_IN_ARR);
                                $arr = array();
                            } else {
                                if ($this->use & SERVICES_JSON_LOOSE_TYPE) {
                                    $stk = array(SERVICES_JSON_IN_OBJ);
                                    $obj = array();
                                } else {
                                    $stk = array(SERVICES_JSON_IN_OBJ);
                                    $obj = new stdClass();
                                }
                            }

                            array_push($stk, array('what'  => SERVICES_JSON_SLICE,
                                                   'where' => 0,
                                                   'delim' => false));

                            $chrs = $this->substr8($str, 1, -1);
                            $chrs = $this->reduce_string($chrs);

                            if ($chrs == '') {
                                if (reset($stk) == SERVICES_JSON_IN_ARR) {
                                    return $arr;

                                } else {
                                    return $obj;

                                }
                            }

                            //print("\nparsing {$chrs}\n");

                            $strlen_chrs = $this->strlen8($chrs);

                            for ($c = 0; $c <= $strlen_chrs; ++$c) {

                                $top = end($stk);
                                $substr_chrs_c_2 = $this->substr8($chrs, $c, 2);

                                if (($c == $strlen_chrs) || (($chrs{$c} == ',') && ($top['what'] == SERVICES_JSON_SLICE))) {
                                    // found a comma that is not inside a string, array, etc.,
                                    // OR we've reached the end of the character list
                                    $slice = $this->substr8($chrs, $top['where'], ($c - $top['where']));
                                    array_push($stk, array('what' => SERVICES_JSON_SLICE, 'where' => ($c + 1), 'delim' => false));
                                    //print("Found split at {$c}: ".$this->substr8($chrs, $top['where'], (1 + $c - $top['where']))."\n");

                                    if (reset($stk) == SERVICES_JSON_IN_ARR) {
                                        // we are in an array, so just push an element onto the stack
                                        array_push($arr, $this->decode($slice));

                                    } elseif (reset($stk) == SERVICES_JSON_IN_OBJ) {
                                        // we are in an object, so figure
                                        // out the property name and set an
                                        // element in an associative array,
                                        // for now
                                        $parts = array();

                                       if (preg_match('/^\s*(["\'].*[^\\\]["\'])\s*:/Uis', $slice, $parts)) {
                                          // "name":value pair
                                            $key = $this->decode($parts[1]);
                                            $val = $this->decode(trim(substr($slice, strlen($parts[0])), ", \t\n\r\0\x0B"));
                                            if ($this->use & SERVICES_JSON_LOOSE_TYPE) {
                                                $obj[$key] = $val;
                                            } else {
                                                $obj->$key = $val;
                                            }
                                        } elseif (preg_match('/^\s*(\w+)\s*:/Uis', $slice, $parts)) {
                                            // name:value pair, where name is unquoted
                                            $key = $parts[1];
                                            $val = $this->decode(trim(substr($slice, strlen($parts[0])), ", \t\n\r\0\x0B"));

                                            if ($this->use & SERVICES_JSON_LOOSE_TYPE) {
                                                $obj[$key] = $val;
                                            } else {
                                                $obj->$key = $val;
                                            }
                                        }

                                    }

                                } elseif ((($chrs{$c} == '"') || ($chrs{$c} == "'")) && ($top['what'] != SERVICES_JSON_IN_STR)) {
                                    // found a quote, and we are not inside a string
                                    array_push($stk, array('what' => SERVICES_JSON_IN_STR, 'where' => $c, 'delim' => $chrs{$c}));
                                    //print("Found start of string at {$c}\n");

                                } elseif (($chrs{$c} == $top['delim']) &&
                                         ($top['what'] == SERVICES_JSON_IN_STR) &&
                                         (($this->strlen8($this->substr8($chrs, 0, $c)) - $this->strlen8(rtrim($this->substr8($chrs, 0, $c), '\\'))) % 2 != 1)) {
                                    // found a quote, we're in a string, and it's not escaped
                                    // we know that it's not escaped becase there is _not_ an
                                    // odd number of backslashes at the end of the string so far
                                    array_pop($stk);
                                    //print("Found end of string at {$c}: ".$this->substr8($chrs, $top['where'], (1 + 1 + $c - $top['where']))."\n");

                                } elseif (($chrs{$c} == '[') &&
                                         in_array($top['what'], array(SERVICES_JSON_SLICE, SERVICES_JSON_IN_ARR, SERVICES_JSON_IN_OBJ))) {
                                    // found a left-bracket, and we are in an array, object, or slice
                                    array_push($stk, array('what' => SERVICES_JSON_IN_ARR, 'where' => $c, 'delim' => false));
                                    //print("Found start of array at {$c}\n");

                                } elseif (($chrs{$c} == ']') && ($top['what'] == SERVICES_JSON_IN_ARR)) {
                                    // found a right-bracket, and we're in an array
                                    array_pop($stk);
                                    //print("Found end of array at {$c}: ".$this->substr8($chrs, $top['where'], (1 + $c - $top['where']))."\n");

                                } elseif (($chrs{$c} == '{') &&
                                         in_array($top['what'], array(SERVICES_JSON_SLICE, SERVICES_JSON_IN_ARR, SERVICES_JSON_IN_OBJ))) {
                                    // found a left-brace, and we are in an array, object, or slice
                                    array_push($stk, array('what' => SERVICES_JSON_IN_OBJ, 'where' => $c, 'delim' => false));
                                    //print("Found start of object at {$c}\n");

                                } elseif (($chrs{$c} == '}') && ($top['what'] == SERVICES_JSON_IN_OBJ)) {
                                    // found a right-brace, and we're in an object
                                    array_pop($stk);
                                    //print("Found end of object at {$c}: ".$this->substr8($chrs, $top['where'], (1 + $c - $top['where']))."\n");

                                } elseif (($substr_chrs_c_2 == '/*') &&
                                         in_array($top['what'], array(SERVICES_JSON_SLICE, SERVICES_JSON_IN_ARR, SERVICES_JSON_IN_OBJ))) {
                                    // found a comment start, and we are in an array, object, or slice
                                    array_push($stk, array('what' => SERVICES_JSON_IN_CMT, 'where' => $c, 'delim' => false));
                                    $c++;
                                    //print("Found start of comment at {$c}\n");

                                } elseif (($substr_chrs_c_2 == '*/') && ($top['what'] == SERVICES_JSON_IN_CMT)) {
                                    // found a comment end, and we're in one now
                                    array_pop($stk);
                                    $c++;

                                    for ($i = $top['where']; $i <= $c; ++$i)
                                        $chrs = substr_replace($chrs, ' ', $i, 1);

                                    //print("Found end of comment at {$c}: ".$this->substr8($chrs, $top['where'], (1 + $c - $top['where']))."\n");

                                }

                            }

                            if (reset($stk) == SERVICES_JSON_IN_ARR) {
                                return $arr;

                            } elseif (reset($stk) == SERVICES_JSON_IN_OBJ) {
                                return $obj;

                            }

                        }
                }
            }


            /**
             * @todo Ultimately, this should just call PEAR::isError()
             */
            function isError($data, $code = null)
            {
                if (class_exists('pear')) {
                    return PEAR::isError($data, $code);
                } elseif (is_object($data) && (get_class($data) == 'services_json_error' ||
                                         is_subclass_of($data, 'services_json_error'))) {
                    return true;
                }

                return false;
            }

            /**
            * Calculates length of string in bytes
            * @param string
            * @return integer length
            */
            function strlen8( $str )
            {
                if ( $this->_mb_strlen ) {
                    return mb_strlen( $str, "8bit" );
                }
                return strlen( $str );
            }

            /**
            * Returns part of a string, interpreting $start and $length as number of bytes.
            * @param string
            * @param integer start
            * @param integer length
            * @return integer length
            */
            function substr8( $string, $start, $length=false )
            {
                if ( $length === false ) {
                    $length = $this->strlen8( $string ) - $start;
                }
                if ( $this->_mb_substr ) {
                    return mb_substr( $string, $start, $length, "8bit" );
                }
                return substr( $string, $start, $length );
            }

            }
}

    if (class_exists('PEAR_Error')) {

        class Services_JSON_Error extends PEAR_Error
        {
            function Services_JSON_Error($message = 'unknown error', $code = null,
                                         $mode = null, $options = null, $userinfo = null)
            {
                parent::PEAR_Error($message, $code, $mode, $options, $userinfo);
            }
        }

    } else {

        /**
         * @todo Ultimately, this class shall be descended from PEAR_Error
         */
        if (class_exists('PEAR_Error')) {
            class Services_JSON_Error
            {
                function Services_JSON_Error($message = 'unknown error', $code = null,
                                             $mode = null, $options = null, $userinfo = null)
                {

                }
            }
        }
    }

    define('XAPP_JSON_CLASS',true);
}
