function callCallbackFunctionIfPassed(args, data) {
	//is last args is a function, call it. The others are passed as parameter back to the callback function
	if(args.length>=1) {
		var func = args[args.length-1];
			if(typeof(func)=="function") {
			func.call(this, data);
		}
	}
}

function errorHandler(e) {
	alert(e);
}

function requestData(args, url) {
	xmlhttp.open("get", url);
		xmlhttp.send(null);
		
		xmlhttp.onreadystatechange = function() {
				if(xmlhttp.readyState==4) {
					if(xmlhttp.status==404) {
						errorHandler("Check your config.php file; Installation path is not filled properly");	
					}
					callCallbackFunctionIfPassed(args, evalJSON(xmlhttp.responseText));
			}
		}
}

function toJSON(object) {
	for(var i=0; i<object.length; i++) {
		//alert(typeof(object[i]));	
		var type = typeof object[i];
		switch (type) {
		  case 'undefined':
		  case 'function':
		  case 'unknown': return;
		  case 'boolean': return object[i].toString();
		}
		if (object[i] === null) return 'null';
		if (toJSON(object[i])) return toJSON(object[i]);
		if (Object.isElement(object[i])) return;
		var results = [];
		for (var property in object[i]) {
			var value = Object.toJSON(object[i][property]);
		  	if (!Object.isUndefined(value))
				results.push(property.toJSON() + ': ' + value);
		}
		
	
		return '{' + results.join(', ') + '}';
	
	}
}

function iter(iterable) {
  if (!iterable) return [];
  if (iterable.toArray) return iterable.toArray();
  var length = iterable.length || 0, results = new Array(length);
  while (length--) results[length] = iterable[length];
  return results;
}


try { 
    xmlhttp = new ActiveXObject("Msxml2.XMLHTTP"); 
} catch (e) { 
    try { 
        xmlhttp = new ActiveXObject("Microsoft.XMLHTTP"); 
    } catch (E) { 
        xmlhttp = false; 
    } 
} 

if  (!xmlhttp && typeof  XMLHttpRequest != 'undefined' ) { 
    try  { 
        xmlhttp = new  XMLHttpRequest(); 
    } catch  (e) { 
        xmlhttp = false ; 
    } 
} 

/**
* Eval no valor em JSON
*/
function evalJSON (sanitize) {
    try {
	 if (sanitize) return eval('(' + sanitize + ')');
    } catch (e) {throw e; }
    
}



/*
    http://www.JSON.org/json2.js
    2008-11-19

    Public Domain.

    NO WARRANTY EXPRESSED OR IMPLIED. USE AT YOUR OWN RISK.

    See http://www.JSON.org/js.html

    This file creates a global JSON object containing two methods: stringify
    and parse.

        JSON.stringify(value, replacer, space)
            value       any JavaScript value, usually an object or array.

            replacer    an optional parameter that determines how object
                        values are stringified for objects. It can be a
                        function or an array of strings.

            space       an optional parameter that specifies the indentation
                        of nested structures. If it is omitted, the text will
                        be packed without extra whitespace. If it is a number,
                        it will specify the number of spaces to indent at each
                        level. If it is a string (such as '\t' or '&nbsp;'),
                        it contains the characters used to indent at each level.

            This method produces a JSON text from a JavaScript value.
*/

if (!this.JSON) {
    JSON = {};
}
(function () {

    function f(n) {
        // Format integers to have at least two digits.
        return n < 10 ? '0' + n : n;
    }

    if (typeof Date.prototype.toJSON !== 'function') {

        Date.prototype.toJSON = function (key) {

            return this.getUTCFullYear()   + '-' +
                 f(this.getUTCMonth() + 1) + '-' +
                 f(this.getUTCDate())      + 'T' +
                 f(this.getUTCHours())     + ':' +
                 f(this.getUTCMinutes())   + ':' +
                 f(this.getUTCSeconds())   + 'Z';
        };

        String.prototype.toJSON =
        Number.prototype.toJSON =
        Boolean.prototype.toJSON = function (key) {
            return this.valueOf();
        };
    }

    var cx = /[\u0000\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,
        escapable = /[\\\"\x00-\x1f\x7f-\x9f\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,
        gap,
        indent,
        meta = {    // table of character substitutions
            '\b': '\\b',
            '\t': '\\t',
            '\n': '\\n',
            '\f': '\\f',
            '\r': '\\r',
            '"' : '\\"',
            '\\': '\\\\'
        },
        rep;


    function quote(string) {
        escapable.lastIndex = 0;
        return escapable.test(string) ?
            '"' + string.replace(escapable, function (a) {
                var c = meta[a];
                return typeof c === 'string' ? c :
                    '\\u' + ('0000' + a.charCodeAt(0).toString(16)).slice(-4);
            }) + '"' :
            '"' + string + '"';
    }


    function str(key, holder) {


        var i,          // The loop counter.
            k,          // The member key.
            v,          // The member value.
            length,
            mind = gap,
            partial,
            value = holder[key];


        if (value && typeof value === 'object' &&
                typeof value.toJSON === 'function') {
            value = value.toJSON(key);
        }


        if (typeof rep === 'function') {
            value = rep.call(holder, key, value);
        }

        switch (typeof value) {
        case 'string':
            return '"'  + value + '"';

        case 'number':

            return isFinite(value) ? String(value) : 'null';

        case 'boolean':
        case 'null':

        return String(value);
        case 'object':

            if (!value) {
                return 'null';
            }
            gap += indent;
            partial = [];
            if (Object.prototype.toString.apply(value) === '[object Array]') {

                length = value.length;
                for (i = 0; i < length; i += 1) {
                    partial[i] = str(i, value) || 'null';
                }

                v = partial.length === 0 ? '[]' :
                    gap ? '[\n' + gap +
                            partial.join(',\n' + gap) + '\n' +
                                mind + ']' :
                          '[' + partial.join(',') + ']';
                gap = mind;
                return v;
            }

            if (rep && typeof rep === 'object') {
                length = rep.length;
                for (i = 0; i < length; i += 1) {
                    k = rep[i];
                    if (typeof k === 'string') {
                        v = str(k, value);
                        if (v) {
                            partial.push(quote(k) + (gap ? ': ' : ':') + v);
                        }
                    }
                }
            } else {

               for (k in value) {
                    if (Object.hasOwnProperty.call(value, k)) {
                        v = str(k, value);
                        if (v) {
                            partial.push(quote(k) + (gap ? ': ' : ':') + v);
                        }
                    }
                }
            }


            v = partial.length === 0 ? '{}' :
                gap ? '{\n' + gap + partial.join(',\n' + gap) + '\n' +
                        mind + '}' : '{' + partial.join(',') + '}';
            gap = mind;
            return v;
        }
    }

    if (typeof JSON.stringify != 'function') {
        JSON.stringify = function (value, replacer, space) {


            var i;
            gap = '';
            indent = '';


            if (typeof space === 'number') {
                for (i = 0; i < space; i += 1) {
                    indent += ' ';
                }


            } else if (typeof space === 'string') {
                indent = space;
            }


            rep = replacer;
            if (replacer && typeof replacer !== 'function' &&
                    (typeof replacer !== 'object' ||
                     typeof replacer.length !== 'number')) {
                throw new Error('JSON.stringify');
            }



            return str('', {'': value});
        };
    }




    if (typeof JSON.parse !== 'function') {
        JSON.parse = function (text, reviver) {



            var j;

            function walk(holder, key) {



                var k, v, value = holder[key];
                if (value && typeof value === 'object') {
                    for (k in value) {
                        if (Object.hasOwnProperty.call(value, k)) {
                            v = walk(value, k);
                            if (v !== undefined) {
                                value[k] = v;
                            } else {
                                delete value[k];
                            }
                        }
                    }
                }
                return reviver.call(holder, key, value);
            }




            cx.lastIndex = 0;
            if (cx.test(text)) {
                text = text.replace(cx, function (a) {
                    return '\\u' +
                        ('0000' + a.charCodeAt(0).toString(16)).slice(-4);
                });
            }



            if (/^[\],:{}\s]*$/.
test(text.replace(/\\(?:["\\\/bfnrt]|u[0-9a-fA-F]{4})/g, '@').
replace(/"[^"\\\n\r]*"|true|false|null|-?\d+(?:\.\d*)?(?:[eE][+\-]?\d+)?/g, ']').
replace(/(?:^|:|,)(?:\s*\[)+/g, ''))) {

// In the third stage we use the eval function to compile the text into a
// JavaScript structure. The '{' operator is subject to a syntactic ambiguity
// in JavaScript: it can begin a block or an object literal. We wrap the text
// in parens to eliminate the ambiguity.

                j = eval('(' + text + ')');

// In the optional fourth stage, we recursively walk the new structure, passing
// each name/value pair to a reviver function for possible transformation.

                return typeof reviver === 'function' ?
                    walk({'': j}, '') : j;
            }

// If the text is not JSON parseable, then a SyntaxError is thrown.

            throw new SyntaxError('JSON.parse');
        };
    }
})();