json.php

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    function name_value($name, $value)
    {
        return (sprintf("%s:%s", $this->encode(strval($name)), $this->encode($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  $str    JSON-formatted string
    *
    * @return   mixed   number, boolean, string, array, or object
    *                   corresponding to given JSON input string.
    *                   See argument 1 to JSON() above for object-output behavior.
    *                   Note that decode() always returns strings
    *                   in ASCII or UTF-8 format!
    * @access   public
    */
    function decode($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('/^("|\').+("|\')$/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 ($substr_chrs_c_2) {
                            case '\b':  $utf8 .= chr(0x08);  $c+=1;  break;
                            case '\t':  $utf8 .= chr(0x09);  $c+=1;  break;
                            case '\n':  $utf8 .= chr(0x0A);  $c+=1;  break;
                            case '\f':  $utf8 .= chr(0x0C);  $c+=1;  break;
                            case '\r':  $utf8 .= chr(0x0D);  $c+=1;  break;

                            case '\\"':
                            case '\\\'':
                            case '\\\\':
                            case '\\/':
                                if (($delim == '"' && $substr_chrs_c_2 != '\\\'') ||
                                   ($delim == "'" && $substr_chrs_c_2 != '\\"')) {
                                    $utf8 .= $chrs{++$c};
                                }
                                break;
                                
                            default:
                                if (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)));
                                    $utf8 .= mb_convert_encoding($utf16, 'UTF-8', 'UTF-16');
                                    $c+=5;
        
                                } elseif(($ord_chrs_c >= 0x20) && ($ord_chrs_c <= 0x7F)) {
                                    $utf8 .= $chrs{$c};
        
                                } elseif(($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 += 1;
    
                                } elseif(($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;
    
                                } elseif(($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;
    
                                } elseif(($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;
    
                                } elseif(($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(JSON_IN_ARR);
                        $arr = array();
                    } else {
                        if ($this->use == JSON_LOOSE_TYPE) {
                            $stk = array(JSON_IN_OBJ);
                            $obj = array();
                        } else {
                            $stk = array(JSON_IN_OBJ);
                            $obj = new stdClass();
                        }
                    }
                    
                    array_push($stk, array('what'  => JSON_SLICE,
                                           'where' => 0,
                                           'delim' => false));

                    $chrs = substr($str, 1, -1);
                    $chrs = $this->reduce_string($chrs);
                    
                    if ($chrs == '') {
                        if (reset($stk) == 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'] == 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' => JSON_SLICE, 'where' => ($c + 1), 'delim' => false));
                            //print("Found split at {$c}: ".substr($chrs, $top['where'], (1 + $c - $top['where']))."\n");

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

                            } elseif (reset($stk) == 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 == 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 == JSON_LOOSE_TYPE) {
                                        $obj[$key] = $val;
                                    } else {
                                        $obj->$key = $val;
                                    }
                                }

                            }

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

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

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

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

                        } elseif (($chrs{$c} == '}') && ($top['what'] == JSON_IN_OBJ)) {
                            // found a right-brace, and we're in an object
                            array_pop($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(JSON_SLICE, JSON_IN_ARR, JSON_IN_OBJ))) {
                            // found a comment start, and we are in an array, object, or slice
                            array_push($stk, array('what' => JSON_IN_CMT, 'where' => $c, 'delim' => false));
                            $c++;
                            //print("Found start of comment at {$c}\n");

                        } elseif (($substr_chrs_c_2 == '*/') && ($top['what'] == 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) == JSON_IN_ARR) {
                        return $arr;

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

                    }
                
                }
        }
    }
    
   /**
    * decodes a JSON string into appropriate variable; alias for decode()
    */
    function dec($var)
    {
        return $this->decode($var);
    }
    
}
    
?>