/lib/pear/HTML/AJAX/JSON.php

<?php

/**

 * This is an embedded version of HTML_AJAX_JSON since it has yet to have

 * a PEAR release it has been renamed to HTML_AJAX_JSON so no problems

 * will be caused by an eventual release

 * Feel free to report bugs against it to HTML_AJAX

 *

 * SVN Rev: $Id: JSON.php,v 1.1.2.1 2008/10/03 07:07:32 nicolasconnault Exp $

 */



/**

 * Needed for compat functions

 */

require_once 'HTML/AJAX.php';



/**

 * 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     HTML_AJAX_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

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

 * @link        http://pear.php.net/pepr/pepr-proposal-show.php?id=198

 */



/**

 * Marker constant for HTML_AJAX_JSON::decode(), used to flag stack state

 */

define('SERVICES_JSON_SLICE',   1);



/**

 * Marker constant for HTML_AJAX_JSON::decode(), used to flag stack state

 */

define('SERVICES_JSON_IN_STR',  2);



/**

 * Marker constant for HTML_AJAX_JSON::decode(), used to flag stack state

 */

define('SERVICES_JSON_IN_ARR',  3);



/**

 * Marker constant for HTML_AJAX_JSON::decode(), used to flag stack state

 */

define('SERVICES_JSON_IN_OBJ',  4);



/**

 * Marker constant for HTML_AJAX_JSON::decode(), used to flag stack state

 */

define('SERVICES_JSON_IN_CMT', 5);



/**

 * Behavior switch for HTML_AJAX_JSON::decode()

 */

define('SERVICES_JSON_LOOSE_TYPE', 16);



/**

 * Behavior switch for HTML_AJAX_JSON::decode()

 */

define('SERVICES_JSON_SUPPRESS_ERRORS', 32);



/**

 * Converts to and from JSON format.

 *

 * Brief example of use:

 *

 * <code>

 * // create a new instance of HTML_AJAX_JSON

 * $json = new HTML_AJAX_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 HTML_AJAX_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 HTML_AJAX_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

    *

    * @param    mixed   $var    any number, boolean, string, array, or object to be encoded.

    *                           see argument 1 to HTML_AJAX_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

                            $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):

                            // 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):

                            // 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

                            $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):

                            // 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(HTML_AJAX_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(HTML_AJAX_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(HTML_AJAX_JSON::isError($property))

                        return $property;



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



            default:

                return ($this->use & SERVICES_JSON_SUPPRESS_ERRORS)

                    ? 'null'

                    : new HTML_AJAX_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(HTML_AJAX_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 HTML_AJAX_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:

                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

                                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) &&

                                 (($chrs{$c - 1} != '\\') ||

                                 ($chrs{$c - 1} == '\\' && $chrs{$c - 2} == '\\'))) {

                            // found a quote, we're in a string, and it's not escaped

                            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 (HTML_AJAX_class_exists('pear', false)) {

            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 (HTML_AJAX_class_exists('pear_error', false)) {



    class HTML_AJAX_JSON_Error extends PEAR_Error

    {

        function HTML_AJAX_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 HTML_AJAX_JSON_Error

    {

        function HTML_AJAX_JSON_Error($message = 'unknown error', $code = null,

                                     $mode = null, $options = null, $userinfo = null)

        {



        }

    }



}



// Future-friendly json_encode

if( !function_exists('json_encode') ) {

	function json_encode($data) {

        $json = new HTML_AJAX_JSON();

        return( $json->encode($data) );

    }

}



// Future-friendly json_decode

if( !function_exists('json_decode') ) {

	function json_decode($data) {

        $json = new HTML_AJAX_JSON();

        return( $json->decode($data) );

    }

}

/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */

?>