var btnArrowLeft = document.getElementById("btnArrowLt");
var btnArrowRight = document.getElementById("btnArrowRt");

//assign event handlers
btnArrowLeft.onclick = scrollLt;
btnArrowLeft.onmouseover = toggleLtArrow;
btnArrowLeft.onmouseout = toggleLtArrow;
btnArrowRight.onclick = scrollRt;
btnArrowRight.onmouseover = toggleRtArrow;
btnArrowRight.onmouseout = toggleRtArrow;

var morePanel = document.getElementById("divBIFrame");
var arrMoreRows = morePanel.getElementsByTagName("div");
var moreItemWidth = 240;

var morePos = morePanel.scrollLeft;
var moreStart = 0;
var moreEnd = moreItemWidth*(arrMoreRows.length-1);
var moreLength = moreItemWidth;
var moreIncrement = 10;
var r, l;

//set default left arrow to disabled
btnArrowLeft.src = "/images/btnArrowLt_disabled.gif"; 
btnArrowLeft.style.cursor = "default";

if (arrMoreRows.length < 2) {
    btnArrowRight.src = "/images/btnArrowRt_disabled.gif"; 
    btnArrowRight.style.cursor = "default";
}

function scrollRt() {
    if ( (morePos < moreEnd) && (morePos < moreStart+moreLength) ) {
        morePos = morePos + moreIncrement;
        morePanel.scrollLeft = morePos;
        r = setTimeout(scrollRt, 1);
    } else {
        moreStart = morePanel.scrollLeft;
        clearTimeout(r);
        if (morePos > 0) { btnArrowLeft.src = "/images/btnArrowLt.gif"; btnArrowLeft.style.cursor = "pointer"; }
        if (morePos > (moreEnd-moreLength)) { btnArrowRight.src = "/images/btnArrowRt_disabled.gif"; btnArrowRight.style.cursor = "default"; }
    }
}

function scrollLt() {
    if ( (morePos > 0) && (morePos > moreStart-moreLength) ) {
        morePos = morePos - moreIncrement;
        morePanel.scrollLeft = morePos;
        l = setTimeout(scrollLt, 1);
    } else {
        moreStart = morePanel.scrollLeft;
        clearTimeout(l);
        if (morePos === 0 ) { btnArrowLeft.src = "/images/btnArrowLt_disabled.gif"; btnArrowLeft.style.cursor = "default"; }
        if (morePos < moreEnd) { btnArrowRight.src = "/images/btnArrowRt.gif"; btnArrowRight.style.cursor = "pointer"; }
    }
}

function toggleLtArrow(ev) {
    var imgPath;
    if (morePos === 0) {
        imgPath = this.src.substring(this.src.indexOf("/images"), this.src.length);
        if (imgPath !== "/images/btnArrowLt_disabled.gif") {
            this.src="/images/btnArrowLt_disabled.gif";
        }
    } else {
        ev = ev || window.event;
        if (ev.type === "mouseover") {
            this.src="/images/btnArrowLt_over.gif";
	    } else if (ev.type === "mouseup") {
            this.src="/images/btnArrowLt_over.gif";
        } else {
            this.src="/images/btnArrowLt.gif";
        }
    }
}

function toggleRtArrow(ev) {
    var imgPath;
    if (morePos > (moreEnd-moreLength)) {
        imgPath = this.src.substring(this.src.indexOf("/images"), this.src.length);
        if (imgPath !== "/images/btnArrowRt_disabled.gif") {
            this.src="/images/btnArrowRt_disabled.gif";
        }
    } else {
        ev = ev || window.event;
        if (ev.type === "mouseover") {
            this.src="/images/btnArrowRt_over.gif";
 	    } else if (ev.type === "mouseup") {
            this.src="/images/btnArrowRt_over.gif";
        } else {
            this.src="/images/btnArrowRt.gif";
        }
    }
}