<?php
if ( !class_exists( 'Services_JSON' ) ) :
    /* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */
    /**
     * 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		Services_JSON
     * @author		Michal Migurski <mike-json@teczno.com>
     * @author		Matt Knapp <mdknapp[at]gmail[dot]com>
     * @author		Brett Stimmerman <brettstimmerman[at]gmail[dot]com>
     * @copyright	2005 Michal Migurski
     * @version     CVS: $Id: JSON.php 288200 2009-09-09 15:41:29Z alan_k $
     * @license		http://www.opensource.org/licenses/bsd-license.php
     * @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);

    /**
     * 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>
     */
    class Services_JSON
    {
        /**
         * constructs a new JSON instance
         *
         * @param int $use object behavior flags; combine with boolean-OR
         *
         *						possible values:
         *						- SERVICES_JSON_LOOSE_TYPE:  loose typing.
         *								"{...}" syntax creates associative arrays
         *								instead of objects in decode().
         *						- SERVICES_JSON_SUPPRESS_ERRORS:  error suppression.
         *								Values which can't be encoded (e.g. resources)
         *								appear as NULL instead of throwing errors.
         *								By default, a deeply-nested resource will
         *								bubble up with an error, so all return values
         *								from encode() should be checked with isError()
         */
        function Services_JSON($use = 0)
        {
            $this->use = $use;
        }

        /**
         * 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(function_exists('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(function_exists('mb_convert_encoding')) {
                return mb_convert_encoding($utf8, 'UTF-16', 'UTF-8');
            }

            switch(strlen($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 '';
        }

        /**
         * 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 $this->_encode($var);
        }
        /**
         * encodes an arbitrary variable into JSON format without JSON Header - warning - may allow CSS!!!!)
         *
         * @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)
        {
            return $this->_encode($var);
        }
        /**
         * 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)
        {

            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 = '';
                    $strlen_var = strlen($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))) {
                        $properties = array_map(array($this, 'name_value'),
                            array_keys($var),
                            array_values($var));

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

                        return '{' . join(',', $properties) . '}';
                    }

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

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

                    return '[' . join(',', $elements) . ']';

                case 'object':
                    $vars = get_object_vars($var);

                    $properties = array_map(array($this, 'name_value'),
                        array_keys($vars),
                        array_values($vars));

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

                    return '{' . join(',', $properties) . '}';

                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;
            }

            return $this->_encode(strval($name)) . ':' . $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
                        $delim = substr($str, 0, 1);
                        $chrs = substr($str, 1, -1);
                        $utf8 = '';
                        $strlen_chrs = strlen($chrs);

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

                            $substr_chrs_c_2 = substr($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', substr($chrs, $c, 6)):
                                    // single, escaped unicode character
                                    $utf16 = chr(hexdec(substr($chrs, ($c + 2), 2)))
                                        . chr(hexdec(substr($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
                                    $utf8 .= substr($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
                                    $utf8 .= substr($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
                                    $utf8 .= substr($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
                                    $utf8 .= substr($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
                                    $utf8 .= substr($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));

                        $chrs = substr($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");

                        $strlen_chrs = strlen($chrs);

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

                            $top = end($stk);
                            $substr_chrs_c_2 = substr($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
                                $slice = substr($chrs, $top['where'], ($c - $top['where']));
                                array_push($stk, array('what' => SERVICES_JSON_SLICE, 'where' => ($c + 1), 'delim' => false));
                                //print("Found split at {$c}: ".substr($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*:\s*(\S.*),?$/Uis', $slice, $parts)) {
                                        // "name":value pair
                                        $key = $this->decode($parts[1]);
                                        $val = $this->decode($parts[2]);

                                        if ($this->use & SERVICES_JSON_LOOSE_TYPE) {
                                            $obj[$key] = $val;
                                        } else {
                                            $obj->$key = $val;
                                        }
                                    } elseif (preg_match('/^\s*(\w+)\s*:\s*(\S.*),?$/Uis', $slice, $parts)) {
                                        // name:value pair, where name is unquoted
                                        $key = $parts[1];
                                        $val = $this->decode($parts[2]);

                                        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) &&
                                ((strlen(substr($chrs, 0, $c)) - strlen(rtrim(substr($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 {$c}: ".substr($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 {$c}: ".substr($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 {$c}: ".substr($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 {$c}: ".substr($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;
        }
    }

    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
         */
        class Services_JSON_Error
        {
            function Services_JSON_Error($message = 'unknown error', $code = null,
                                         $mode = null, $options = null, $userinfo = null)
            {

            }
        }

    }
endif;


/**
 * 为了兼容低版本的php而增加的函数集
 * json从5.2.0开始支持，wordpress 2.9开始提供json函数的兼容性代码
 */
if ( !function_exists('json_encode') ) {
    function json_encode( $string ) {
        global $wp_json;

        if ( !is_a($wp_json, 'Services_JSON') ) {
            $wp_json = new Services_JSON();
        }

        return $wp_json->encodeUnsafe( $string );
    }
}

if ( !function_exists('json_decode') ) {
    function json_decode( $string, $assoc_array = false ) {
        global $wp_json;

        if ( !is_a($wp_json, 'Services_JSON') ) {
            $wp_json = new Services_JSON();
        }

        $res = $wp_json->decode( $string );
        if ( $assoc_array )
            $res = _json_decode_object_helper( $res );
        return $res;
    }
    function _json_decode_object_helper($data) {
        if ( is_object($data) )
            $data = get_object_vars($data);
        return is_array($data) ? array_map(__FUNCTION__, $data) : $data;
    }
}