// Core javascript helper functions

// basic browser identification & version
var isOpera = (navigator.userAgent.indexOf("Opera")>=0) && parseFloat(navigator.appVersion);
var isIE = ((document.all) && (!isOpera)) && parseFloat(navigator.appVersion.split("MSIE ")[1].split(";")[0]);

// Cross-browser event handlers.
function addEvent(obj, evType, fn) {
    if (obj.addEventListener) {
        obj.addEventListener(evType, fn, false);
        return true;
    } else if (obj.attachEvent) {
        var r = obj.attachEvent("on" + evType, fn);
        return r;
    } else {
        return false;
    }
}

function removeEvent(obj, evType, fn) {
    if (obj.removeEventListener) {
        obj.removeEventListener(evType, fn, false);
        return true;
    } else if (obj.detachEvent) {
        obj.detachEvent("on" + evType, fn);
        return true;
    } else {
        return false;
    }
}

// quickElement(tagType, parentReference, textInChildNode, [, attribute, attributeValue ...]);
function quickElement() {
    var obj = document.createElement(arguments[0]);
    if (arguments[2] != '' && arguments[2] != null) {
        var textNode = document.createTextNode(arguments[2]);
        obj.appendChild(textNode);
    }
    var len = arguments.length;
    for (var i = 3; i < len; i += 2) {
        obj.setAttribute(arguments[i], arguments[i+1]);
    }
    arguments[1].appendChild(obj);
    return obj;
}

// ----------------------------------------------------------------------------
// Cross-browser xmlhttp object
// from http://jibbering.com/2002/4/httprequest.html
// ----------------------------------------------------------------------------
var xmlhttp;
/*@cc_on @*/
/*@if (@_jscript_version >= 5)
    try {
        xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
    } catch (e) {
        try {
            xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
        } catch (E) {
            xmlhttp = false;
        }
    }
@else
    xmlhttp = false;
@end @*/
if (!xmlhttp && typeof XMLHttpRequest != 'undefined') {
  xmlhttp = new XMLHttpRequest();
}

// ----------------------------------------------------------------------------
// Find-position functions by PPK
// See http://www.quirksmode.org/js/findpos.html
// ----------------------------------------------------------------------------
function findPosX(obj) {
    var curleft = 0;
    if (obj.offsetParent) {
        while (obj.offsetParent) {
            curleft += obj.offsetLeft - ((isOpera) ? 0 : obj.scrollLeft);
            obj = obj.offsetParent;
        }
        // IE offsetParent does not include the top-level 
        if (isIE && obj.parentElement){
            curleft += obj.offsetLeft - obj.scrollLeft;
        }
    } else if (obj.x) {
        curleft += obj.x;
    }
    return curleft;
}

function findPosY(obj) {
    var curtop = 0;
    if (obj.offsetParent) {
        while (obj.offsetParent) {
            curtop += obj.offsetTop - ((isOpera) ? 0 : obj.scrollTop);
            obj = obj.offsetParent;
        }
        // IE offsetParent does not include the top-level 
        if (isIE && obj.parentElement){
            curtop += obj.offsetTop - obj.scrollTop;
        }
    } else if (obj.y) {
        curtop += obj.y;
    }
    return curtop;
}

//-----------------------------------------------------------------------------
// Date object extensions
// ----------------------------------------------------------------------------
Date.prototype.getCorrectYear = function() {
    // Date.getYear() is unreliable --
    // see http://www.quirksmode.org/js/introdate.html#year
    var y = this.getYear() % 100;
    return (y < 38) ? y + 2000 : y + 1900;
}

Date.prototype.getTwelveHours = function() {
    return (this.getHours() <= 12) ? this.getHours() : 24 - this.getHours();
}

Date.prototype.getTwoDigitMonth = function() {
    return (this.getMonth() < 9) ? '0' + (this.getMonth()+1) : (this.getMonth()+1);
}

Date.prototype.getTwoDigitDate = function() {
    return (this.getDate() < 10) ? '0' + this.getDate() : this.getDate();
}

Date.prototype.getTwoDigitTwelveHour = function() {
    return (this.getTwelveHours() < 10) ? '0' + this.getTwelveHours() : this.getTwelveHours();
}

Date.prototype.getTwoDigitHour = function() {
    return (this.getHours() < 10) ? '0' + this.getHours() : this.getHours();
}

Date.prototype.getTwoDigitMinute = function() {
    return (this.getMinutes() < 10) ? '0' + this.getMinutes() : this.getMinutes();
}

Date.prototype.getTwoDigitSecond = function() {
    return (this.getSeconds() < 10) ? '0' + this.getSeconds() : this.getSeconds();
}

Date.prototype.getISODate = function() {
    return this.getCorrectYear() + '-' + this.getTwoDigitMonth() + '-' + this.getTwoDigitDate();
}

Date.prototype.getHourMinute = function() {
    return this.getTwoDigitHour() + ':' + this.getTwoDigitMinute();
}

Date.prototype.getHourMinuteSecond = function() {
    return this.getTwoDigitHour() + ':' + this.getTwoDigitMinute() + ':' + this.getTwoDigitSecond();
}

Date.prototype.strftime = function(format) {
    var fields = {
        c: this.toString(),
        d: this.getTwoDigitDate(),
        H: this.getTwoDigitHour(),
        I: this.getTwoDigitTwelveHour(),
        m: this.getTwoDigitMonth(),
        M: this.getTwoDigitMinute(),
        p: (this.getHours() >= 12) ? 'PM' : 'AM',
        S: this.getTwoDigitSecond(),
        w: '0' + this.getDay(),
        x: this.toLocaleDateString(),
        X: this.toLocaleTimeString(),
        y: ('' + this.getFullYear()).substr(2, 4),
        Y: '' + this.getFullYear(),
        '%' : '%'
    };
    var result = '', i = 0;
    while (i < format.length) {
        if (format.charAt(i) === '%') {
            result = result + fields[format.charAt(i + 1)];
            ++i;
        }
        else {
            result = result + format.charAt(i);
        }
        ++i;
    }
    return result;
}

// ----------------------------------------------------------------------------
// String object extensions
// ----------------------------------------------------------------------------
String.prototype.pad_left = function(pad_length, pad_string) {
    var new_string = this;
    for (var i = 0; new_string.length < pad_length; i++) {
        new_string = pad_string + new_string;
    }
    return new_string;
}

// ----------------------------------------------------------------------------
// Get the computed style for and element
// ----------------------------------------------------------------------------
function getStyle(oElm, strCssRule){
    var strValue = "";
    if(document.defaultView && document.defaultView.getComputedStyle){
        strValue = document.defaultView.getComputedStyle(oElm, "").getPropertyValue(strCssRule);
    }
    else if(oElm.currentStyle){
        strCssRule = strCssRule.replace(/\-(\w)/g, function (strMatch, p1){
            return p1.toUpperCase();
        });
        strValue = oElm.currentStyle[strCssRule];
    }
    return strValue;
}
