// vertical scroll area
var VSA_scrollAreas = new Array();
var VSA_default_imagesPath = "/images";
var VSA_default_btnUpImage = "btn-up.gif";
var VSA_default_btnDownImage = "btn-down.gif";
var VSA_default_scrollStep = 5;
var VSA_default_wheelSensitivity = 10;
var VSA_default_scrollbarPosition = 'right'; //'left','right','inline';
var VSA_default_scrollButtonHeight = 17;
var VSA_default_scrollbarWidth = 19;
var VSA_resizeTimer = 2000;
var VSA_touchFlag = isTouchDevice(); // true/false - move scroll with scrollable body

if (window.addEventListener) window.addEventListener("load", VSA_initScrollbars, false);
else if (window.attachEvent) window.attachEvent("onload", VSA_initScrollbars);

function VSA_initScrollbars()
{
    if (!document.body.children) return;
    var scrollElements = VSA_getElements("vscrollable", "DIV", document, "class");
    for (var i = 0; i < scrollElements.length; i++)
    {
        VSA_scrollAreas[i] = new VScrollArea(i, scrollElements[i]);
    }
}

function isTouchDevice()
{
    try
    {
        document.createEvent("TouchEvent");
        return true;
    } catch (e)
    {
        return false;
    }
}

function touchHandler(event)
{
    var touches = event.changedTouches, first = touches[0], type = "";
    switch (event.type)
    {
        case "touchstart": type = "mousedown"; break;
        case "touchmove": type = "mousemove"; break;
        case "touchend": type = "mouseup"; break;
        default: return;
    }
    var simulatedEvent = document.createEvent("MouseEvent");
    simulatedEvent.initMouseEvent(type, true, true, window, 1, first.screenX, first.screenY, first.clientX, first.clientY, false, false, false, false, 0/*left*/, null);
    first.target.dispatchEvent(simulatedEvent);
    event.preventDefault();
}

function VScrollArea(index, elem) //constructor
{
    this.index = index;
    this.element = elem;

    var attr = this.element.getAttribute("imagesPath");
    this.imagesPath = attr ? attr : VSA_default_imagesPath;

    attr = this.element.getAttribute("btnUpImage");
    this.btnUpImage = attr ? attr : VSA_default_btnUpImage;

    attr = this.element.getAttribute("btnDownImage");
    this.btnDownImage = attr ? attr : VSA_default_btnDownImage;

    attr = Number(this.element.getAttribute("scrollStep"));
    this.scrollStep = attr ? attr : VSA_default_scrollStep;

    attr = Number(this.element.getAttribute("wheelSensitivity"));
    this.wheelSensitivity = attr ? attr : VSA_default_wheelSensitivity;

    attr = this.element.getAttribute("scrollbarPosition");
    this.scrollbarPosition = attr ? attr : VSA_default_scrollbarPosition;

    attr = this.element.getAttribute("scrollButtonHeight");
    this.scrollButtonHeight = attr ? attr : VSA_default_scrollButtonHeight;

    attr = this.element.getAttribute("scrollbarWidth");
    this.scrollbarWidth = attr ? attr : VSA_default_scrollbarWidth;

    this.scrolling = false;

    this.iOffsetY = 0;
    this.scrollHeight = 0;
    this.scrollContent = null;
    this.scrollbar = null;
    this.scrollup = null;
    this.scrolldown = null;
    this.scrollslider = null;
    this.scroll = null;
    this.enableScrollbar = false;
    this.scrollFactor = 1;
    this.scrollingLimit = 0;
    this.topPosition = 0;

    //functions declaration
    this.init = VSA_init;
    this.scrollUp = VSA_scrollUp;
    this.scrollDown = VSA_scrollDown;
    this.createScrollBar = VSA_createScrollBar;
    this.scrollIt = VSA_scrollIt;

    this.init();
}

function VSA_init()
{
    this.scrollContent = document.createElement("DIV");
    this.scrollContent.style.position = "absolute";
    this.scrollContent.style.overflow = "hidden";
    this.scrollContent.style.width = this.element.offsetWidth + "px";
    this.scrollContent.style.height = this.element.offsetHeight + "px";

    while (this.element.childNodes.length) this.scrollContent.appendChild(this.element.childNodes[0]);

    this.element.style.overflow = "hidden";
    this.element.style.display = "block";
    this.element.style.visibility = "visible";
    this.element.style.position = "relative";
    this.element.appendChild(this.scrollContent);

    this.scrollContent.className = 'scroll-content';

    this.element.index = this.index;
    this.element.over = false;

    var _this = this;

    if (document.all && !window.opera)
    {
        this.element.onmouseenter = function () { _this.element.over = true; };
        this.element.onmouseleave = function () { _this.element.over = false; }
    } else
    {
        this.element.onmouseover = function () { _this.element.over = true; };
        this.element.onmouseout = function () { _this.element.over = false; }
    }

    if (document.all)
    {
        this.element.onscroll = VSA_handleOnScroll;
        this.element.onresize = VSA_handleResize;
    }
    else
    {
        window.onresize = VSA_handleResize;
    }

    this.createScrollBar();

    if (window.addEventListener)
    {
        /* DOMMouseScroll is for mozilla. */
        this.element.addEventListener('DOMMouseScroll', VSA_handleMouseWheel, false);
    }
    /* IE/Opera. */
    this.element.onmousewheel = document.onmousewheel = VSA_handleMouseWheel;

    // move content by touch
    if (VSA_touchFlag)
    {
        _this.scrollContent.onmousedown = function (e)
        {
            var startY = e.pageY - getRealTop(_this.scrollContent);
            var origTop = _this.scrollContent.scrollTop;
            _this.scrollContent.onmousemove = function (e)
            {
                var moveY = e.pageY - getRealTop(_this.scrollContent);
                var iNewY = origTop - (moveY - startY);
                if (iNewY < 0) iNewY = 0;
                if (iNewY > _this.scrollContent.scrollHeight) iNewY = _this.scrollContent.scrollHeight;
                _this.scrollContent.scrollTop = iNewY;
                _this.scrollslider.style.top = 1 / _this.scrollFactor * Math.abs(_this.scrollContent.scrollTop) + _this.scrollButtonHeight + "px";
            }
        }
        _this.scrollContent.onmouseup = function (e)
        {
            _this.scrollContent.onmousemove = null;
        }
        this.scrollContent.addEventListener("touchstart", touchHandler, true);
        this.scrollContent.addEventListener("touchmove", touchHandler, true);
        this.scrollContent.addEventListener("touchend", touchHandler, true);
    }
}

function VSA_createScrollBar()
{
    if (this.scrollbar != null)
    {
        this.element.removeChild(this.scrollbar);
        this.scrollbar = null;
    }

    if (this.scrollContent.scrollHeight <= this.scrollContent.offsetHeight)
        this.enableScrollbar = false;
    else if (this.element.offsetHeight > 2 * this.scrollButtonHeight)
        this.enableScrollbar = true;
    else
        this.enableScrollbar = false;

    if (this.scrollContent.scrollHeight - Math.abs(this.scrollContent.scrollTop) < this.element.offsetHeight)
        this.scrollContent.style.top = 0;

    if (this.enableScrollbar)
    {
        this.scrollbar = document.createElement("DIV");
        this.element.appendChild(this.scrollbar);
        this.scrollbar.style.position = "absolute";
        this.scrollbar.style.top = "0px";
        this.scrollbar.style.height = this.element.offsetHeight + "px";
        this.scrollbar.style.width = this.scrollbarWidth + "px";

        this.scrollbar.className = 'vscroll-bar';

        if (this.scrollbarWidth != this.scrollbar.offsetWidth)
        {
            this.scrollbarWidth = this.scrollbar.offsetHeight;
        }

        this.scrollbarWidth = this.scrollbar.offsetWidth;

        if (this.scrollbarPosition == 'left')
        {
            this.scrollContent.style.left = this.scrollbarWidth + 5 + "px";
            this.scrollContent.style.width = this.element.offsetWidth - this.scrollbarWidth - 5 + "px";
        }
        else if (this.scrollbarPosition == 'right')
        {
            this.scrollbar.style.left = this.element.offsetWidth - this.scrollbarWidth + "px";
            this.scrollContent.style.width = this.element.offsetWidth - this.scrollbarWidth - 5 + "px";
        }

        //create scroll up button
        this.scrollup = document.createElement("DIV");
        this.scrollup.index = this.index;
        this.scrollup.onmousedown = VSA_handleBtnUpMouseDown;
        this.scrollup.onmouseup = VSA_handleBtnUpMouseUp;
        this.scrollup.onmouseout = VSA_handleBtnUpMouseOut;

        if (VSA_touchFlag)
        {
            this.scrollup.addEventListener("touchstart", touchHandler, true);
            this.scrollup.addEventListener("touchend", touchHandler, true);
        }

        this.scrollup.style.position = "absolute";
        this.scrollup.style.top = "0px";
        this.scrollup.style.left = "0px";
        this.scrollup.style.height = this.scrollButtonHeight + "px";
        this.scrollup.style.width = this.scrollbarWidth + "px";

        this.scrollup.innerHTML = '<img src="' + this.imagesPath + '/' + this.btnUpImage + '" border="0"/>';
        this.scrollbar.appendChild(this.scrollup);

        this.scrollup.className = 'vscroll-up';

        if (this.scrollButtonHeight != this.scrollup.offsetHeight)
        {
            this.scrollButtonHeight = this.scrollup.offsetHeight;
        }

        //create scroll down button
        this.scrolldown = document.createElement("DIV");
        this.scrolldown.index = this.index;
        this.scrolldown.onmousedown = VSA_handleBtnDownMouseDown;
        this.scrolldown.onmouseup = VSA_handleBtnDownMouseUp;
        this.scrolldown.onmouseout = VSA_handleBtnDownMouseOut;

        if (VSA_touchFlag)
        {
            this.scrolldown.addEventListener("touchstart", touchHandler, true);
            this.scrolldown.addEventListener("touchend", touchHandler, true);
        }

        this.scrolldown.style.position = "absolute";
        this.scrolldown.style.left = "0px";
        this.scrolldown.style.top = this.scrollbar.offsetHeight - this.scrollButtonHeight + "px";
        this.scrolldown.style.width = this.scrollbarWidth + "px";
        this.scrolldown.innerHTML = '<img src="' + this.imagesPath + '/' + this.btnDownImage + '" border="0"/>';
        this.scrollbar.appendChild(this.scrolldown);

        this.scrolldown.className = 'vscroll-down';

        //create scroll
        this.scroll = document.createElement("DIV");
        this.scroll.index = this.index;
        this.scroll.style.position = "absolute";
        this.scroll.style.zIndex = 0;
        this.scroll.style.textAlign = "center";
        this.scroll.style.top = this.scrollButtonHeight + "px";
        this.scroll.style.left = "0px";
        this.scroll.style.width = this.scrollbarWidth + "px";

        var h = this.scrollbar.offsetHeight - 2 * this.scrollButtonHeight;
        this.scroll.style.height = ((h > 0) ? h : 0) + "px";

        this.scroll.innerHTML = '';
        this.scroll.onclick = VSA_handleScrollbarClick;
        this.scrollbar.appendChild(this.scroll);
        this.scroll.style.overflow = "hidden";

        this.scroll.className = "vscroll-line";

        //create slider
        this.scrollslider = document.createElement("DIV");
        this.scrollslider.index = this.index;
        this.scrollslider.style.position = "absolute";
        this.scrollslider.style.zIndex = 1000;
        this.scrollslider.style.textAlign = "center";
        this.scrollslider.innerHTML = '<div id="vscrollslider' + this.index + '" style="padding:0;margin:0;"><div class="scroll-bar-top"></div><div class="scroll-bar-bottom"></div></div>';
        this.scrollbar.appendChild(this.scrollslider);

        this.subscrollslider = document.getElementById("vscrollslider" + this.index);
        this.subscrollslider.style.height = Math.round((this.scrollContent.offsetHeight / this.scrollContent.scrollHeight) * (this.scrollbar.offsetHeight - 2 * this.scrollButtonHeight)) + "px";

        this.scrollslider.className = "vscroll-slider";

        this.scrollHeight = this.scrollbar.offsetHeight - 2 * this.scrollButtonHeight - this.scrollslider.offsetHeight;
        this.scrollFactor = (this.scrollContent.scrollHeight - this.scrollContent.offsetHeight) / this.scrollHeight;
        this.topPosition = getRealTop(this.scrollbar) + this.scrollButtonHeight;
        /* this.scrollbarHeight = this.scrollbar.offsetHeight - 2*this.scrollButtonHeight - this.scrollslider.offsetHeight; */

        this.scrollslider.style.top = /* 1 / this.scrollFactor * Math.abs(this.scrollContent.offsetTop) +*/this.scrollButtonHeight + "px";
        this.scrollslider.style.left = "0px";
        this.scrollslider.style.width = "100%";
        this.scrollslider.onmousedown = VSA_handleSliderMouseDown;
        if (VSA_touchFlag)
        {
            this.scrollslider.addEventListener("touchstart", touchHandler, true);
        }
        if (document.all)
            this.scrollslider.onmouseup = VSA_handleSliderMouseUp;
    }
    else
        this.scrollContent.style.width = this.element.offsetWidth + "px";
}

function VSA_handleBtnUpMouseDown()
{
    var sa = VSA_scrollAreas[this.index];
    sa.scrolling = true;
    sa.scrollUp();
}

function VSA_handleBtnUpMouseUp()
{
    VSA_scrollAreas[this.index].scrolling = false;
}

function VSA_handleBtnUpMouseOut()
{
    VSA_scrollAreas[this.index].scrolling = false;
}

function VSA_handleBtnDownMouseDown()
{
    var sa = VSA_scrollAreas[this.index];
    sa.scrolling = true;
    sa.scrollDown();
}

function VSA_handleBtnDownMouseUp()
{
    VSA_scrollAreas[this.index].scrolling = false;
}

function VSA_handleBtnDownMouseOut()
{
    VSA_scrollAreas[this.index].scrolling = false;
}

function VSA_scrollIt()
{
    this.scrollContent.scrollTop = this.scrollFactor * ((this.scrollslider.offsetTop + this.scrollslider.offsetHeight / 2) - this.scrollButtonHeight - this.scrollslider.offsetHeight / 2);
}

function VSA_scrollUp()
{
    if (this.scrollingLimit > 0)
    {
        this.scrollingLimit--;
        if (this.scrollingLimit == 0) this.scrolling = false;
    }
    if (!this.scrolling) return;
    if (this.scrollContent.scrollTop - this.scrollStep > 0)
    {
        this.scrollContent.scrollTop -= this.scrollStep;
        this.scrollslider.style.top = 1 / this.scrollFactor * Math.abs(this.scrollContent.scrollTop) + this.scrollButtonHeight + "px";
    }
    else
    {
        this.scrollContent.scrollTop = "0";
        this.scrollslider.style.top = this.scrollButtonHeight + "px";
        return;
    }
    setTimeout("VSA_Ext_scrollUp(" + this.index + ")", 30);
}

function VSA_Ext_scrollUp(index)
{
    VSA_scrollAreas[index].scrollUp();
}

function VSA_scrollDown()
{
    if (this.scrollingLimit > 0)
    {
        this.scrollingLimit--;
        if (this.scrollingLimit == 0) this.scrolling = false;
    }
    if (!this.scrolling) return;


    this.scrollContent.scrollTop += this.scrollStep;
    this.scrollslider.style.top = 1 / this.scrollFactor * Math.abs(this.scrollContent.scrollTop) + this.scrollButtonHeight + "px";

    if (this.scrollContent.scrollTop >= (this.scrollContent.scrollHeight - this.scrollContent.offsetHeight))
    {
        this.scrollContent.scrollTop = (this.scrollContent.scrollHeight - this.scrollContent.offsetHeight);
        this.scrollslider.style.top = this.scrollbar.offsetHeight - this.scrollButtonHeight - this.scrollslider.offsetHeight + "px";
        return;
    }

    setTimeout("VSA_Ext_scrollDown(" + this.index + ")", 30);
}

function VSA_Ext_scrollDown(index)
{
    VSA_scrollAreas[index].scrollDown();
}

function VSA_handleMouseMove(evt)
{
    var sa = VSA_scrollAreas[((document.all && !window.opera) ? this.index : document.documentElement.scrollAreaIndex)];
    var posy = 0;
    if (!evt) var evt = window.event;

    if (evt.pageY)
        posy = evt.pageY;
    else if (evt.clientY)
        posy = evt.clientY;

    if (document.all && !window.opera)
    {
        if (!document.addEventListener)
        {
            posy += document.documentElement.scrollTop;
        }
    }

    var iNewY = posy - sa.iOffsetY - getRealTop(sa.scrollbar) - sa.scrollButtonHeight;
    iNewY += sa.scrollButtonHeight;

    if (iNewY < sa.scrollButtonHeight)
        iNewY = sa.scrollButtonHeight;
    if (iNewY > (sa.scrollbar.offsetHeight - sa.scrollButtonHeight) - sa.scrollslider.offsetHeight)
        iNewY = (sa.scrollbar.offsetHeight - sa.scrollButtonHeight) - sa.scrollslider.offsetHeight;

    sa.scrollslider.style.top = iNewY + "px";

    sa.scrollIt();
}

function VSA_handleSliderMouseDown(evt)
{
    if (!(document.uniqueID && document.compatMode && !window.XMLHttpRequest))
    {
        document.onselectstart = function () { return false; }
        document.onmousedown = function () { return false; }
    }

    var sa = VSA_scrollAreas[this.index];
    if (document.all && !window.opera)
    {
        sa.scrollslider.setCapture()
        sa.iOffsetY = event.offsetY;
        sa.scrollslider.onmousemove = VSA_handleMouseMove;
        if (VSA_touchFlag)
        {
            sa.scrollslider.addEventListener("touchmove", touchHandler, true);
        }
    }
    else
    {
        if (window.opera)
        {
            sa.iOffsetY = event.offsetY;
        }
        else
        {
            sa.iOffsetY = evt.layerY;
        }
        document.documentElement.scrollAreaIndex = sa.index;
        document.documentElement.addEventListener("mousemove", VSA_handleMouseMove, true);
        document.documentElement.addEventListener("mouseup", VSA_handleSliderMouseUp, true);
        if (VSA_touchFlag)
        {
            document.documentElement.addEventListener("touchmove", touchHandler, true);
            document.documentElement.addEventListener("touchend", touchHandler, true);
        }
    }
    return false;
}

function VSA_handleSliderMouseUp()
{
    if (!(document.uniqueID && document.compatMode && !window.XMLHttpRequest))
    {
        document.onmousedown = null;
        document.onselectstart = null;
    }

    if (document.all && !window.opera)
    {
        var sa = VSA_scrollAreas[this.index];
        sa.scrollslider.onmousemove = null;
        sa.scrollslider.releaseCapture();
        sa.scrollIt();
    }
    else
    {
        var sa = VSA_scrollAreas[document.documentElement.scrollAreaIndex];
        document.documentElement.removeEventListener("mousemove", VSA_handleMouseMove, true);
        document.documentElement.removeEventListener("mouseup", VSA_handleSliderMouseUp, true);
        if (VSA_touchFlag)
        {
            document.documentElement.removeEventListener("touchmove", touchHandler, true);
            document.documentElement.removeEventListener("touchend", touchHandler, true);
        }
        sa.scrollIt();
    }
    return false;
}

function VSA_handleResize()
{
    if (VSA_resizeTimer)
    {
        clearTimeout(VSA_resizeTimer);
        VSA_resizeTimer = 0;
    }
    VSA_resizeTimer = setTimeout("VSA_performResizeEvent()", 100);
}

function VSA_performResizeEvent()
{
    for (var i = 0; i < VSA_scrollAreas.length; i++)
        VSA_scrollAreas[i].createScrollBar();
}
function VSA_handleMouseWheel(event)
{
    if (this.index != null)
    {
        var sa = VSA_scrollAreas[this.index];
        if (sa.scrollbar == null) return;
        sa.scrolling = true;
        sa.scrollingLimit = sa.wheelSensitivity;

        var delta = 0;
        if (!event) /* For IE. */
            event = window.event;
        if (event.wheelDelta)
        { /* IE/Opera. */
            delta = event.wheelDelta / 120;
            /*if (window.opera) delta = -delta;*/
        } else if (event.detail)
        { /* Mozilla case. */
            delta = -event.detail / 3;
        }

        if (delta && sa.element.over)
        {
            if (delta > 0)
            {
                sa.scrollUp();
            } else
            {
                sa.scrollDown();
            }
            if (event.preventDefault)
            {
                event.preventDefault();
            }
            event.returnValue = false;
        }
    }
}

function VSA_handleSelectStart()
{
    event.returnValue = false;
}

function VSA_handleScrollbarClick(evt)
{
    var sa = VSA_scrollAreas[this.index];
    var offsetY = (document.all ? event.offsetY : evt.layerY);

    if (offsetY < (sa.scrollButtonHeight + sa.scrollslider.offsetHeight / 2))
        sa.scrollslider.style.top = sa.scrollButtonHeight + "px";
    else if (offsetY > (sa.scrollbar.offsetHeight - sa.scrollButtonHeight - sa.scrollslider.offsetHeight))
        sa.scrollslider.style.top = sa.scrollbar.offsetHeight - sa.scrollButtonHeight - sa.scrollslider.offsetHeight + "px";
    else
    {
        sa.scrollslider.style.top = offsetY + sa.scrollButtonHeight - sa.scrollslider.offsetHeight / 2 + "px";
    }
    sa.scrollIt();
}

function VSA_handleOnScroll()
{
    //event.srcElement.doScroll("pageUp");
}

//--- common functions ----

function VSA_getElements(attrValue, tagName, ownerNode, attrName) //get Elements By Attribute Name
{
    if (!tagName) tagName = "*";
    if (!ownerNode) ownerNode = document;
    if (!attrName) attrName = "name";
    var result = [];
    var nl = ownerNode.getElementsByTagName(tagName);
    for (var i = 0; i < nl.length; i++)
    {
        //	if (nl.item(i).getAttribute(attrName) == attrValue)
        //		result.push(nl.item(i));
        if (nl.item(i).className.indexOf(attrValue) != -1)
            result.push(nl.item(i));
    }
    return result;
}

function getRealTop(obj)
{
    var posTop = 0;
    while (obj.offsetParent)
    {
        posTop += obj.offsetTop;
        obj = obj.offsetParent;
    }
    return posTop;
}