// create namespace
var util = {};

/**
 * Test whether given object is a number
 * @param {*} object
 * @return {Boolean} isNumber
 */
util.isNumber = function isNumber(object) {
    return (object instanceof Number || typeof object == 'number');
};

/**
 * Test whether given object is a string
 * @param {*} object
 * @return {Boolean} isString
 */
util.isString = function isString(object) {
    return (object instanceof String || typeof object == 'string');
};

/**
 * Test whether given object is a Date, or a String containing a Date
 * @param {Date | String} object
 * @return {Boolean} isDate
 */
util.isDate = function isDate(object) {
    if (object instanceof Date) {
        return true;
    }
    else if (util.isString(object)) {
        // test whether this string contains a date
        var match = ASPDateRegex.exec(object);
        if (match) {
            return true;
        }
        else if (!isNaN(Date.parse(object))) {
            return true;
        }
    }

    return false;
};

/**
 * Test whether given object is an instance of google.visualization.DataTable
 * @param {*} object
 * @return {Boolean} isDataTable
 */
util.isDataTable = function isDataTable(object) {
    return (typeof (google) !== 'undefined') &&
        (google.visualization) &&
        (google.visualization.DataTable) &&
        (object instanceof google.visualization.DataTable);
};

/**
 * Create a semi UUID
 * source: http://stackoverflow.com/a/105074/1262753
 * @return {String} uuid
 */
util.randomUUID = function randomUUID () {
    var S4 = function () {
        return Math.floor(
            Math.random() * 0x10000 /* 65536 */
        ).toString(16);
    };

    return (
        S4() + S4() + '-' +
            S4() + '-' +
            S4() + '-' +
            S4() + '-' +
            S4() + S4() + S4()
        );
};

/**
 * Extend object a with the properties of object b
 * @param {Object} a
 * @param {Object} b
 * @return {Object} a
 */
util.extend = function (a, b) {
    for (var prop in b) {
        if (b.hasOwnProperty(prop)) {
            a[prop] = b[prop];
        }
    }
    return a;
};

/**
 * Cast an object to another type
 * @param {Boolean | Number | String | Date | Null | undefined} object
 * @param {String | function | undefined} type   Name of the type or a cast
 *                                               function. Available types:
 *                                               'Boolean', 'Number', 'String',
 *                                               'Date', ISODate', 'ASPDate'.
 * @return {*} object
 * @throws Error
 */
util.cast = function cast(object, type) {
    if (object === undefined) {
        return undefined;
    }
    if (object === null) {
        return null;
    }

    if (!type) {
        return object;
    }
    if (typeof type == 'function') {
        return type(object);
    }

    //noinspection FallthroughInSwitchStatementJS
    switch (type) {
        case 'boolean':
        case 'Boolean':
            return Boolean(object);

        case 'number':
        case 'Number':
            return Number(object);

        case 'string':
        case 'String':
            return String(object);

        case 'Date':
            if (util.isNumber(object)) {
                return new Date(object);
            }
            if (object instanceof Date) {
                return new Date(object.valueOf());
            }
            if (util.isString(object)) {
                // parse ASP.Net Date pattern,
                // for example '/Date(1198908717056)/' or '/Date(1198908717056-0700)/'
                // code from http://momentjs.com/
                var match = ASPDateRegex.exec(object);
                if (match) {
                    return new Date(Number(match[1]));
                }
                else {
                    return moment(object).toDate(); // parse string
                }
            }
            else {
                throw new Error(
                    'Cannot cast object of type ' + util.getType(object) +
                        ' to type Date');
            }

        case 'ISODate':
            if (object instanceof Date) {
                return object.toISOString();
            }
            else if (util.isNumber(object) || util.isString(object)) {
                return moment(object).toDate().toISOString();
            }
            else {
                throw new Error(
                    'Cannot cast object of type ' + util.getType(object) +
                        ' to type ISODate');
            }

        case 'ASPDate':
            if (object instanceof Date) {
                return '/Date(' + object.valueOf() + ')/';
            }
            else if (util.isNumber(object) || util.isString(object)) {
                return '/Date(' + moment(object).valueOf() + ')/';
            }
            else {
                throw new Error(
                    'Cannot cast object of type ' + util.getType(object) +
                        ' to type ASPDate');
            }

        default:
            throw new Error('Cannot cast object of type ' + util.getType(object) +
                ' to type "' + type + '"');
    }
};

var ASPDateRegex = /^\/?Date\((\-?\d+)/i;

/**
 * Get the type of an object, for example util.getType([]) returns 'Array'
 * @param {*} object
 * @return {String} type
 */
util.getType = function getType(object) {
    var type = typeof object;

    if (type == 'object') {
        if (object == null) {
            return 'null';
        }
        if (object instanceof Boolean) {
            return 'Boolean';
        }
        if (object instanceof Number) {
            return 'Number';
        }
        if (object instanceof String) {
            return 'String';
        }
        if (object instanceof Array) {
            return 'Array';
        }
        if (object instanceof Date) {
            return 'Date';
        }
        return 'Object';
    }
    else if (type == 'number') {
        return 'Number';
    }
    else if (type == 'boolean') {
        return 'Boolean';
    }
    else if (type == 'string') {
        return 'String';
    }

    return type;
};

/**
 * Retrieve the absolute left value of a DOM element
 * @param {Element} elem        A dom element, for example a div
 * @return {number} left        The absolute left position of this element
 *                              in the browser page.
 */
util.getAbsoluteLeft = function getAbsoluteLeft (elem) {
    var doc = document.documentElement;
    var body = document.body;

    var left = elem.offsetLeft;
    var e = elem.offsetParent;
    while (e != null && e != body && e != doc) {
        left += e.offsetLeft;
        left -= e.scrollLeft;
        e = e.offsetParent;
    }
    return left;
};

/**
 * Retrieve the absolute top value of a DOM element
 * @param {Element} elem        A dom element, for example a div
 * @return {number} top        The absolute top position of this element
 *                              in the browser page.
 */
util.getAbsoluteTop = function getAbsoluteTop (elem) {
    var doc = document.documentElement;
    var body = document.body;

    var top = elem.offsetTop;
    var e = elem.offsetParent;
    while (e != null && e != body && e != doc) {
        top += e.offsetTop;
        top -= e.scrollTop;
        e = e.offsetParent;
    }
    return top;
};

/**
 * Get the absolute, vertical mouse position from an event.
 * @param {Event} event
 * @return {Number} pageY
 */
util.getPageY = function getPageY (event) {
    if ('pageY' in event) {
        return event.pageY;
    }
    else {
        var clientY;
        if (('targetTouches' in event) && event.targetTouches.length) {
            clientY = event.targetTouches[0].clientY;
        }
        else {
            clientY = event.clientY;
        }

        var doc = document.documentElement;
        var body = document.body;
        return clientY +
            ( doc && doc.scrollTop || body && body.scrollTop || 0 ) -
            ( doc && doc.clientTop || body && body.clientTop || 0 );
    }
};

/**
 * Get the absolute, horizontal mouse position from an event.
 * @param {Event} event
 * @return {Number} pageX
 */
util.getPageX = function getPageX (event) {
    if ('pageY' in event) {
        return event.pageX;
    }
    else {
        var clientX;
        if (('targetTouches' in event) && event.targetTouches.length) {
            clientX = event.targetTouches[0].clientX;
        }
        else {
            clientX = event.clientX;
        }

        var doc = document.documentElement;
        var body = document.body;
        return clientX +
            ( doc && doc.scrollLeft || body && body.scrollLeft || 0 ) -
            ( doc && doc.clientLeft || body && body.clientLeft || 0 );
    }
};

/**
 * add a className to the given elements style
 * @param {Element} elem
 * @param {String} className
 */
util.addClassName = function addClassName(elem, className) {
    var classes = elem.className.split(' ');
    if (classes.indexOf(className) == -1) {
        classes.push(className); // add the class to the array
        elem.className = classes.join(' ');
    }
};

/**
 * add a className to the given elements style
 * @param {Element} elem
 * @param {String} className
 */
util.removeClassName = function removeClassname(elem, className) {
    var classes = elem.className.split(' ');
    var index = classes.indexOf(className);
    if (index != -1) {
        classes.splice(index, 1); // remove the class from the array
        elem.className = classes.join(' ');
    }
};

/**
 * For each method for both arrays and objects.
 * In case of an array, the built-in Array.forEach() is applied.
 * In case of an Object, the method loops over all properties of the object.
 * @param {Object | Array} object   An Object or Array
 * @param {function} callback       Callback method, called for each item in
 *                                  the object or array with three parameters:
 *                                  callback(value, index, object)
 */
util.forEach = function forEach (object, callback) {
    if (object instanceof Array) {
        // array
        object.forEach(callback);
    }
    else {
        // object
        for (var key in object) {
            if (object.hasOwnProperty(key)) {
                callback(object[key], key, object);
            }
        }
    }
};

/**
 * Update a property in an object
 * @param {Object} object
 * @param {String} key
 * @param {*} value
 * @return {Boolean} changed
 */
util.updateProperty = function updateProp (object, key, value) {
    if (object[key] !== value) {
        object[key] = value;
        return true;
    }
    else {
        return false;
    }
};

/**
 * Add and event listener. Works for all browsers
 * @param {Element}     element    An html element
 * @param {string}      action     The action, for example "click",
 *                                 without the prefix "on"
 * @param {function}    listener   The callback function to be executed
 * @param {boolean}     [useCapture]
 */
util.addEventListener = function addEventListener(element, action, listener, useCapture) {
    if (element.addEventListener) {
        if (useCapture === undefined)
            useCapture = false;

        if (action === "mousewheel" && navigator.userAgent.indexOf("Firefox") >= 0) {
            action = "DOMMouseScroll";  // For Firefox
        }

        element.addEventListener(action, listener, useCapture);
    } else {
        element.attachEvent("on" + action, listener);  // IE browsers
    }
};

/**
 * Remove an event listener from an element
 * @param {Element}     element         An html dom element
 * @param {string}      action          The name of the event, for example "mousedown"
 * @param {function}    listener        The listener function
 * @param {boolean}     [useCapture]
 */
util.removeEventListener = function removeEventListener(element, action, listener, useCapture) {
    if (element.removeEventListener) {
        // non-IE browsers
        if (useCapture === undefined)
            useCapture = false;

        if (action === "mousewheel" && navigator.userAgent.indexOf("Firefox") >= 0) {
            action = "DOMMouseScroll";  // For Firefox
        }

        element.removeEventListener(action, listener, useCapture);
    } else {
        // IE browsers
        element.detachEvent("on" + action, listener);
    }
};


/**
 * Get HTML element which is the target of the event
 * @param {Event} event
 * @return {Element} target element
 */
util.getTarget = function getTarget(event) {
    // code from http://www.quirksmode.org/js/events_properties.html
    if (!event) {
        event = window.event;
    }

    var target;

    if (event.target) {
        target = event.target;
    }
    else if (event.srcElement) {
        target = event.srcElement;
    }

    if (target.nodeType != undefined && target.nodeType == 3) {
        // defeat Safari bug
        target = target.parentNode;
    }

    return target;
};

/**
 * Stop event propagation
 */
util.stopPropagation = function stopPropagation(event) {
    if (!event)
        event = window.event;

    if (event.stopPropagation) {
        event.stopPropagation();  // non-IE browsers
    }
    else {
        event.cancelBubble = true;  // IE browsers
    }
};


/**
 * Cancels the event if it is cancelable, without stopping further propagation of the event.
 */
util.preventDefault = function preventDefault (event) {
    if (!event)
        event = window.event;

    if (event.preventDefault) {
        event.preventDefault();  // non-IE browsers
    }
    else {
        event.returnValue = false;  // IE browsers
    }
};


util.option = {};

/**
 * Cast a value as boolean
 * @param {Boolean | function | undefined} value
 * @param {Boolean} [defaultValue]
 * @returns {Boolean} bool
 */
util.option.asBoolean = function (value, defaultValue) {
    if (typeof value == 'function') {
        value = value();
    }

    if (value != null) {
        return (value != false);
    }

    return defaultValue || null;
};

/**
 * Cast a value as number
 * @param {Boolean | function | undefined} value
 * @param {Number} [defaultValue]
 * @returns {Number} number
 */
util.option.asNumber = function (value, defaultValue) {
    if (typeof value == 'function') {
        value = value();
    }

    if (value != null) {
        return Number(value);
    }

    return defaultValue || null;
};

/**
 * Cast a value as string
 * @param {String | function | undefined} value
 * @param {String} [defaultValue]
 * @returns {String} str
 */
util.option.asString = function (value, defaultValue) {
    if (typeof value == 'function') {
        value = value();
    }

    if (value != null) {
        return String(value);
    }

    return defaultValue || null;
};

/**
 * Cast a size or location in pixels or a percentage
 * @param {String | Number | function | undefined} value
 * @param {String} [defaultValue]
 * @returns {String} size
 */
util.option.asSize = function (value, defaultValue) {
    if (typeof value == 'function') {
        value = value();
    }

    if (util.isString(value)) {
        return value;
    }
    else if (util.isNumber(value)) {
        return value + 'px';
    }
    else {
        return defaultValue || null;
    }
};

/**
 * Cast a value as DOM element
 * @param {HTMLElement | function | undefined} value
 * @param {HTMLElement} [defaultValue]
 * @returns {HTMLElement | null} dom
 */
util.option.asElement = function (value, defaultValue) {
    if (typeof value == 'function') {
        value = value();
    }

    return value || defaultValue || null;
};


// Internet Explorer 8 and older does not support Array.indexOf, so we define
// it here in that case.
// http://soledadpenades.com/2007/05/17/arrayindexof-in-internet-explorer/
if(!Array.prototype.indexOf) {
    Array.prototype.indexOf = function(obj){
        for(var i = 0; i < this.length; i++){
            if(this[i] == obj){
                return i;
            }
        }
        return -1;
    };

    try {
        console.log("Warning: Ancient browser detected. Please update your browser");
    }
    catch (err) {
    }
}

// Internet Explorer 8 and older does not support Array.forEach, so we define
// it here in that case.
// https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Global_Objects/Array/forEach
if (!Array.prototype.forEach) {
    Array.prototype.forEach = function(fn, scope) {
        for(var i = 0, len = this.length; i < len; ++i) {
            fn.call(scope || this, this[i], i, this);
        }
    }
}

// Internet Explorer 8 and older does not support Array.map, so we define it
// here in that case.
// https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Global_Objects/Array/map
// Production steps of ECMA-262, Edition 5, 15.4.4.19
// Reference: http://es5.github.com/#x15.4.4.19
if (!Array.prototype.map) {
    Array.prototype.map = function(callback, thisArg) {

        var T, A, k;

        if (this == null) {
            throw new TypeError(" this is null or not defined");
        }

        // 1. Let O be the result of calling ToObject passing the |this| value as the argument.
        var O = Object(this);

        // 2. Let lenValue be the result of calling the Get internal method of O with the argument "length".
        // 3. Let len be ToUint32(lenValue).
        var len = O.length >>> 0;

        // 4. If IsCallable(callback) is false, throw a TypeError exception.
        // See: http://es5.github.com/#x9.11
        if (typeof callback !== "function") {
            throw new TypeError(callback + " is not a function");
        }

        // 5. If thisArg was supplied, let T be thisArg; else let T be undefined.
        if (thisArg) {
            T = thisArg;
        }

        // 6. Let A be a new array created as if by the expression new Array(len) where Array is
        // the standard built-in constructor with that name and len is the value of len.
        A = new Array(len);

        // 7. Let k be 0
        k = 0;

        // 8. Repeat, while k < len
        while(k < len) {

            var kValue, mappedValue;

            // a. Let Pk be ToString(k).
            //   This is implicit for LHS operands of the in operator
            // b. Let kPresent be the result of calling the HasProperty internal method of O with argument Pk.
            //   This step can be combined with c
            // c. If kPresent is true, then
            if (k in O) {

                // i. Let kValue be the result of calling the Get internal method of O with argument Pk.
                kValue = O[ k ];

                // ii. Let mappedValue be the result of calling the Call internal method of callback
                // with T as the this value and argument list containing kValue, k, and O.
                mappedValue = callback.call(T, kValue, k, O);

                // iii. Call the DefineOwnProperty internal method of A with arguments
                // Pk, Property Descriptor {Value: mappedValue, : true, Enumerable: true, Configurable: true},
                // and false.

                // In browsers that support Object.defineProperty, use the following:
                // Object.defineProperty(A, Pk, { value: mappedValue, writable: true, enumerable: true, configurable: true });

                // For best browser support, use the following:
                A[ k ] = mappedValue;
            }
            // d. Increase k by 1.
            k++;
        }

        // 9. return A
        return A;
    };
}

// Internet Explorer 8 and older does not support Array.filter, so we define it
// here in that case.
// https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Global_Objects/Array/filter
if (!Array.prototype.filter) {
    Array.prototype.filter = function(fun /*, thisp */) {
        "use strict";

        if (this == null) {
            throw new TypeError();
        }

        var t = Object(this);
        var len = t.length >>> 0;
        if (typeof fun != "function") {
            throw new TypeError();
        }

        var res = [];
        var thisp = arguments[1];
        for (var i = 0; i < len; i++) {
            if (i in t) {
                var val = t[i]; // in case fun mutates this
                if (fun.call(thisp, val, i, t))
                    res.push(val);
            }
        }

        return res;
    };
}


// Internet Explorer 8 and older does not support Object.keys, so we define it
// here in that case.
// https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Global_Objects/Object/keys
if (!Object.keys) {
    Object.keys = (function () {
        var hasOwnProperty = Object.prototype.hasOwnProperty,
            hasDontEnumBug = !({toString: null}).propertyIsEnumerable('toString'),
            dontEnums = [
                'toString',
                'toLocaleString',
                'valueOf',
                'hasOwnProperty',
                'isPrototypeOf',
                'propertyIsEnumerable',
                'constructor'
            ],
            dontEnumsLength = dontEnums.length;

        return function (obj) {
            if (typeof obj !== 'object' && typeof obj !== 'function' || obj === null) {
                throw new TypeError('Object.keys called on non-object');
            }

            var result = [];

            for (var prop in obj) {
                if (hasOwnProperty.call(obj, prop)) result.push(prop);
            }

            if (hasDontEnumBug) {
                for (var i=0; i < dontEnumsLength; i++) {
                    if (hasOwnProperty.call(obj, dontEnums[i])) result.push(dontEnums[i]);
                }
            }
            return result;
        }
    })()
}

// Internet Explorer 8 and older does not support Array.isArray,
// so we define it here in that case.
// https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Global_Objects/Array/isArray
if(!Array.isArray) {
    Array.isArray = function (vArg) {
        return Object.prototype.toString.call(vArg) === "[object Array]";
    };
}

// exports
module.exports = exports = util;