/*
    json.js
    2006-04-28

    This file adds these methods to JavaScript:

        object.toJSONString()

            This method produces a JSON text from an object. The
            object must not contain any cyclical references.

        array.toJSONString()

            This method produces a JSON text from an array. The
            array must not contain any cyclical references.

        string.parseJSON()

            This method parses a JSON text to produce an object or
            array. It will return false if there is an error.
*/
(function () {
    var m = {
            '\b': '\\b',
            '\t': '\\t',
            '\n': '\\n',
            '\f': '\\f',
            '\r': '\\r',
            '"' : '\\"',
            '\\': '\\\\'
        },
        s = {
            array: function (x) {
                var a = ['['], b, f, i, l = x.length, v;
                for (i = 0; i < l; i += 1) {
                    v = x[i];
                    f = s[typeof v];
                    if (f) {
                        v = f(v);
                        if (typeof v == 'string') {
                            if (b) {
                                a[a.length] = ',';
                            }
                            a[a.length] = v;
                            b = true;
                        }
                    }
                }
                a[a.length] = ']';
                return a.join('');
            },
            'boolean': function (x) {
                return String(x);
            },
            'null': function (x) {
                return "null";
            },
            number: function (x) {
                return isFinite(x) ? String(x) : 'null';
            },
            object: function (x) {
                if (x) {
                    if (x instanceof Array) {
                        return s.array(x);
                    }
                    var a = ['{'], b, f, i, v;
                    for (i in x) {
                        v = x[i];
                        f = s[typeof v];
                        if (f) {
                            v = f(v);
                            if (typeof v == 'string') {
                                if (b) {
                                    a[a.length] = ',';
                                }
                                a.push(s.string(i), ':', v);
                                b = true;
                            }
                        }
                    }
                    a[a.length] = '}';
                    return a.join('');
                }
                return 'null';
            },
            string: function (x) {
                if (/["\\\x00-\x1f]/.test(x)) {
                    x = x.replace(/([\x00-\x1f\\"])/g, function(a, b) {
                        var c = m[b];
                        if (c) {
                            return c;
                        }
                        c = b.charCodeAt();
                        return '\\u00' +
                            Math.floor(c / 16).toString(16) +
                            (c % 16).toString(16);
                    });
                }
                return '"' + x + '"';
            }
        };

    Object.prototype.toJSONString = function () {
        return s.object(this);
    };

    Array.prototype.toJSONString = function () {
        return s.array(this);
    };
})();

String.prototype.parseJSON = function () {
    try {
        return !(/[^,:{}\[\]0-9.\-+Eaeflnr-u \n\r\t]/.test(
                this.replace(/"(\\.|[^"\\])*"/g, ''))) &&
            eval('(' + this + ')');
    } catch (e) {
        return false;
    }
};


/** insieme di funzioni ed oggetti utili per interagire con ajax */

	
// funzione per assegnare un oggetto XMLHttpRequest
	function assignXMLHttpRequest() {
		var
			XHR = null,
			browserUtente = navigator.userAgent.toUpperCase();
		if(typeof(XMLHttpRequest) === "function" || typeof(XMLHttpRequest) === "object")
			XHR = new XMLHttpRequest();
		else if(window.ActiveXObject && browserUtente.indexOf("MSIE 4") < 0) {
			if(browserUtente.indexOf("MSIE 5") < 0)
				XHR = new ActiveXObject("Msxml2.XMLHTTP");
			else
				XHR = new ActiveXObject("Microsoft.XMLHTTP");
		}
		return XHR;
	};



/** OGGETTI / ARRAY */

// oggetto di verifica stato
	var readyState = {
		INATTIVO:	0,
		INIZIALIZZATO:	1,
		RICHIESTA:	2,
		RISPOSTA:	3,
		COMPLETATO:	4
	};

// array descrittivo dei codici restituiti dal server
// [la scelta dell' array è per evitare problemi con vecchi browsers]
var statusText = new Array();
statusText[100] = "Continue";
statusText[101] = "Switching Protocols";
statusText[200] = "OK";
statusText[201] = "Created";
statusText[202] = "Accepted";
statusText[203] = "Non-Authoritative Information";
statusText[204] = "No Content";
statusText[205] = "Reset Content";
statusText[206] = "Partial Content";
statusText[300] = "Multiple Choices";
statusText[301] = "Moved Permanently";
statusText[302] = "Found";
statusText[303] = "See Other";
statusText[304] = "Not Modified";
statusText[305] = "Use Proxy";
statusText[306] = "(unused, but reserved)";
statusText[307] = "Temporary Redirect";
statusText[400] = "Bad Request";
statusText[401] = "Unauthorized";
statusText[402] = "Payment Required";
statusText[403] = "Forbidden";
statusText[404] = "Not Found";
statusText[405] = "Method Not Allowed";
statusText[406] = "Not Acceptable";
statusText[407] = "Proxy Authentication Required";
statusText[408] = "Request Timeout";
statusText[409] = "Conflict";
statusText[410] = "Gone";
statusText[411] = "Length Required";
statusText[412] = "Precondition Failed";
statusText[413] = "Request Entity Too Large";
statusText[414] = "Request-URI Too Long";
statusText[415] = "Unsupported Media Type";
statusText[416] = "Requested Range Not Satisfiable";
statusText[417] = "Expectation Failed";
statusText[500] = "Internal Server Error";
statusText[501] = "Not Implemented";
statusText[502] = "Bad Gateway";
statusText[503] = "Service Unavailable";
statusText[504] = "Gateway Timeout";
statusText[505] = "HTTP Version Not Supported";
statusText[509] = "Bandwidth Limit Exceeded";