//populate JSON book object
var tocJson = {
isbn: "9780062083029",
startPg: 0,
pages:
[
{ pGrp: "Outside Front Cover", pNum: 1, pLoc: "97800620830291", imgW: 501, imgH: 750, isLoaded: false },
{ pGrp: "Inside Front Cover", pNum: 2, pLoc: "195601241660584", imgW: 501, imgH: 750, isLoaded: false },
{ pGrp: "Author's Note", pNum: 3, pLoc: "293401862490879", imgW: 501, imgH: 750, isLoaded: false },
{ pGrp: "Dedication", pNum: 4, pLoc: "391202483321176", imgW: 501, imgH: 750, isLoaded: false },
{ pGrp: "Title Page", pNum: 5, pLoc: "489003104151475", imgW: 501, imgH: 750, isLoaded: false },
{ pGrp: "Chapter 1", pNum: 7, pLoc: "684604345812079", imgW: 501, imgH: 750, isLoaded: false },
{ pGrp: "", pNum: 8, pLoc: "782404966642384", imgW: 501, imgH: 750, isLoaded: false },
{ pGrp: "", pNum: 9, pLoc: "880205587472691", imgW: 501, imgH: 750, isLoaded: false },
{ pGrp: "", pNum: 10, pLoc: "9780062083029100", imgW: 501, imgH: 750, isLoaded: false },
{ pGrp: "", pNum: 11, pLoc: "10758068291332021", imgW: 501, imgH: 750, isLoaded: false },
{ pGrp: "", pNum: 12, pLoc: "11736074499634944", imgW: 501, imgH: 750, isLoaded: false },
{ pGrp: "Inside Back Cover", pNum: 35, pLoc: "34230217290602725", imgW: 501, imgH: 750, isLoaded: false },
{ pGrp: "Outside Back Cover", pNum: 36, pLoc: "35208223498905696", imgW: 501, imgH: 750, isLoaded: false } 
]
};


var oBook = eval(tocJson);

// get DOM references to buttons
var btnFitToWindow = document.getElementById("btnFitToWindow");
//var btnZoomOut = document.getElementById("btnZoomOut");
//var btnZoomIn = document.getElementById("btnZoomIn");
var btnMoveHand = document.getElementById("btnMoveHand");
var btnSkipFirst = document.getElementById("btnSkipFirst");
var btnSkipLast = document.getElementById("btnSkipLast");
var btnNext = document.getElementById("btnNext");
var btnPrev = document.getElementById("btnPrev");
var navButtons = document.getElementById("navButtons");
var arrButtons = navButtons.getElementsByTagName("img");
var btnWidget = document.getElementById("btnWidget");
var btnEmail = document.getElementById("btnEmail");
var btnFeedback = document.getElementById("btnFeedback");
var headButtons = document.getElementById("headButtons");
var arrHeadButtons = headButtons.getElementsByTagName("img");
var pageNumber = document.getElementById("pageNumber");

//get DOM references to TOC elements
var toc = document.getElementById("toc");
var btnToc = document.getElementById("btnToc");
var tocStage = document.getElementById("tocStage");
var upArrow = document.getElementById("tocUp");
var downArrow = document.getElementById("tocDown");
var tocPanel = document.getElementById("tocPanel");
var arrTocRows = tocPanel.getElementsByTagName("div");

// get DOM references for Stage
var biHeader = document.getElementById("biHeader");
var sidebar = document.getElementById("sidebar");
var toolbar = document.getElementById("toolbar");
var biLoading = document.getElementById("biLoading");

//set cursor style
if (is_ie) {
	biStage.style.cursor = "url(/images/grab.cur)";
} else if (is_fx) {
	if (is_major >= 2) { biStage.style.cursor = "-moz-grab"; } else { biStage.style.cursor = "move"; }
} else {
	biStage.style.cursor = "move";
}

//XML HTTP REQUEST

function BiPageRequest(pgOrder, curZoom) {
    this.pgOrder = pgOrder;
    if (oBook.pages[this.pgOrder].pLoc.indexOf("getError") > -1) {
        this.pageURL = oBook.pages[this.pgOrder].pLoc + "&reqtype=0";    
    } else {
        this.pageURL = "/Services/GetPage.aspx?isbn13=" + oBook.isbn + "&pageguid=" + oBook.pages[this.pgOrder].pLoc + "&reqtype=0";
    }
    this.isSearchImg = false;
    this.curZoom = curZoom;
    this.req = null;
    this.hasLoaded = false;

    if ((typeof(results) !== "undefined") && (results)) {
        for (i=0; i < results.pages.length; i++) {
            if (results.pages[i].sequence === oBook.pages[this.pgOrder].pNum) {
                this.pageURL = "/Services/GetSearchPage.aspx?isbn13=" + oBook.isbn + "&keyword=" + keyword + "&pageGuid=" + results.pages[i].pageGuid;
                this.isSearchImg = true;
            }
        }
    } 
}

BiPageRequest.prototype.getPageImage = function() {
    var loader;
    this.req = getXMLHTTPRequest();
    if (this.req) {
        addRequest();
        loader = this;
        this.req.onreadystatechange = function() {
            loader.onReadyState.call(loader);
        };
        this.req.open("GET", this.pageURL, true);
        this.req.send(null);
    }
};

BiPageRequest.prototype.onReadyState = function() {
    var req = this.req;
    var oPageResult;
    if (req.readyState === 4) {
        if (req.status === 200) {
            if (!this.isSearchImg) {
                oPageResult = eval("(" + req.responseText + ")");
                arrBookPages[this.pgOrder].innerHTML = "<img src='" + oPageResult.imgUrl + "' unselectable='on' width='" + oBook.pages[this.pgOrder].imgW*this.curZoom + "' height='" + oBook.pages[this.pgOrder].imgH*this.curZoom + "' border='0' onload='removeRequest()' onerror='pageError(this)' />";
            } else {
                arrBookPages[this.pgOrder].innerHTML = "<img src='http://" + req.responseText + "' unselectable='on' width='" + oBook.pages[this.pgOrder].imgW*this.curZoom + "' height='" + oBook.pages[this.pgOrder].imgH*this.curZoom + "' border='0' onload='removeRequest()' onerror='pageError(this)' />";
                arrSearchedPages.push(this.pgOrder);
            }
            
            oBook.pages[this.pgOrder].isLoaded = true;
            this.hasLoaded = true;
        } else {
            alert("There was a problem with the web server. Please try again later.");
            biLoading.style.visibility = "hidden";
        }
    } else {
        window.status = "Loading";
    }
};

//create global requests array to control the number of http request objects
var arrPageRequests = [];
var totalRequests = 0;

function addRequest() { totalRequests++; checkLoadingRequests(); }
function removeRequest() { totalRequests--; checkLoadingRequests(); }
function checkLoadingRequests() {
    if (totalRequests > 0) { biLoading.style.visibility = "visible"; } else { biLoading.style.visibility = "hidden"; }
}

function pageError(theImage) {
    removeRequest();
    theImage.width = "496";
    theImage.height = "750";
    theImage.src = "/images/bi_noimage.gif";
}


//FOR SEARCH / IMAGE HIGHLIGHTING

var arrSearchedPages = [];
function resetSearchedPages(){
    //loop through all pages of the book
    for (i=0; i < oBook.pages.length; i++) {
        //check to see if the page was loaded already
        if (oBook.pages[i].isLoaded) {
            //it has been loaded already, so now loop through the results object
            for (z=0; z < results.pages.length; z++) {
                //and look to see if this particular page is viewable
                //and the results page sequence matches with this book page
                if ((results.pages[z].viewable) && (results.pages[z].sequence === oBook.pages[i].pNum)) {
                    //if it does match, it means this page should be reloaded when it is in view
                    //so reset its loaded flag to false
                    oBook.pages[i].isLoaded = false;
                }
            }
        }
    }
    
    //now wipe clean any previous searched pages
    for (i=0; i < arrSearchedPages.length; i++) {
        oBook.pages[parseInt(arrSearchedPages[i],0)].isLoaded = false;

        //clear the current page if it was a highlighted in a previous search
        if (arrSearchedPages[i] === curPage) {         
            arrPageRequests[curPage] = new BiPageRequest(curPage, curZoomPerc);
            arrPageRequests[curPage].getPageImage();
        }
    }
    
    //loop through the new results object
    for (z=0; z < results.pages.length; z++) {
        //if the results page is viewable and its sequence matches that of the current page
        if ((results.pages[z].viewable) && (results.pages[z].sequence === oBook.pages[curPage].pNum)) {
            //then reload the current page
            arrPageRequests[curPage] = new BiPageRequest(curPage, curZoomPerc);
            arrPageRequests[curPage].getPageImage();
        }
    }
    
    //clear out the requests and search queues            
    arrPageRequests.length = 0;
    arrSearchedPages.length = 0;
}

//START VIEWPORT

//global event handlers
window.onresize = windowResize;
document.onmousemove = windowMouseMove;

//disable right-click
biStage.oncontextmenu = rightClick;
function rightClick(ev) { return false; }

//prevent text selection
document.getElementsByTagName("body")[0].setAttribute("unselectable", "on");
document.getElementsByTagName("body")[0].onselectstart = preventSelection;

function preventSelection(ev) { 
    var targ;
    ev = ev || window.event;
    if (ev.target) { targ = ev.target; }
    else if (ev.srcElement) { targ = ev.srcElement; }
    if (targ.nodeType === 3) { // defeat Safari bug
        targ = targ.parentNode;
    }

    //HACK: txtSiteSearchId is defined as a js variable in the navbar control
    //      the global search box is a server txtbox control with a server id - this was only way to get the id
    if ( ((typeof(txtSiteSearchId) !== "undefined") && (targ.id === txtSiteSearchId)) || (targ.id === "txtEmail") || (targ.id === "txtSearch") ) {
        return true; 
    } else {
        return false;
    }
}

//handle keypress
function disableCtrlKeyCombination(e) {
    var forbiddenKeys = ["a", "c", "x"];
    var key, isCtrl;

    if(window.event) {
        key = window.event.keyCode; //IE
        if(window.event.ctrlKey) { isCtrl = true; } else { isCtrl = false; }
    } else {
        key = e.which; //firefox
        if(e.ctrlKey) { isCtrl = true; } else { isCtrl = false; }
    }

    //if ctrl is pressed check if other key is in forbidenKeys array
    if(isCtrl) {
        for(i=0; i < forbiddenKeys.length; i++) {
            if(forbiddenKeys[i].toLowerCase() === String.fromCharCode(key).toLowerCase()) { return false; }
        }
    }
    return true;
}
document.onkeydown = disableCtrlKeyCombination;
document.onkeypress = disableCtrlKeyCombination;

//set up global variables
var isMouseDown = false;
var startY = null;
var startX = null;
var globalXPos = null;
var globalYPos = null;

var stageTop = findPos(biStage)[1];
var stageLeft = findPos(biStage)[0];
var sidebarWidth = 298; //hardcode this because in ff width value changes with scrollbar, even though visible area does not
var toolBarHeight = 34;
//var stageWidth = document.getElementsByTagName("body")[0].clientWidth - sidebarWidth;
var stageWidth=bodyWidthValue(6);
var stageHeight = document.getElementsByTagName("body")[0].clientHeight - stageTop;

//set width and height of viewport to fix 100% height misinterpretation issue in Firefox
biStage.style.width = stageWidth + "px";
biStage.style.height = stageHeight + "px";

//ie is using 100% height for sidebar, but set it for all other browsers
if (!is_ie) {
    sidebarHeight = document.getElementsByTagName("body")[0].clientHeight - stageTop + toolBarHeight;
    sidebar.style.height = sidebarHeight + "px";
}

// global zoom variables
var curZoomLevel = 4;
var arrZoomInc = [0.6, 0.7, 0.8, 0.9, 1, 1.1];
var curZoomPerc = arrZoomInc[curZoomLevel];

//set position of toc button
if ( (findPos(fitToWindow)[0]-220) > stageLeft ) {
    toc.style.left = (findPos(fitToWindow)[0]-205) + "px";
} else {
    //if it is trying to appear before start of stageLeft, catch it
    toc.style.left = stageLeft + "px";
}

//set position of navigation buttons
if ((findPos(fitToWindow)[0]-390) > (stageLeft)) {
    //navButtons.style.left = (findPos(fitToWindow)[0]-390) + "px";
    navButtons.style.left = ((findPos(fitToWindow)[0])/2)+298-182 + "px";
} else {
    navButtons.style.left = stageLeft;
}

//for firefox scrollwheel support
if ( (window.addEventListener) && (is_fx) ) {
    window.addEventListener("DOMMouseScroll", windowMouseWheel, false);
}

//get the body width including sidebarWidth
function body_width()
{
    var body_width;
    if ($.browser.msie) 
    {
        body_width=$("#main_container").width();
        return body_width;
    }else{
        body_width=$("#main_container").width();
        return body_width;
    }
}

var body_width;
function bodyWidthValue(siteIDValueFromIndexASPX){
    var rightSectionWidth;
    if(siteIDValueFromIndexASPX==13 || siteIDValueFromIndexASPX==14 || siteIDValueFromIndexASPX==1 || siteIDValueFromIndexASPX==9)
    {
        rightSectionWidth=document.getElementsByTagName("body")[0].clientWidth - sidebarWidth;
        return rightSectionWidth;
    }
    else{ //siteID's other than 13,14,1,9
        if (!is_ie){body_width=1003;}else{body_width=983;}
        if(document.getElementsByTagName("body")[0].clientWidth < body_width)
            {
                rightSectionWidth=document.getElementsByTagName("body")[0].clientWidth - sidebarWidth;
                return rightSectionWidth;
            }else{
                rightSectionWidth = body_width - sidebarWidth;
                return rightSectionWidth;
            }//close of if condition
    }//close of if..else condition
}

function windowResize(ev){
    //recalculate stage width/height

    stageTop = findPos(biStage)[1];
    
    //Below code is for unknown body with resolution - if you want this you can uncomment this one
    
    //stageWidth = document.getElementsByTagName("body")[0].clientWidth - sidebarWidth;
    stageWidth = bodyWidthValue(6);
    stageHeight = document.getElementsByTagName("body")[0].clientHeight - stageTop;
    
    if (stageWidth >= 0) {
        biStage.style.width = stageWidth + "px";
    }
    
    if (stageHeight >= 0) {
        biStage.style.height = stageHeight + "px";
    }
    
    //ie is using 100% height for sidebar, but set it for all other browsers
    if (!is_ie) {
        sidebarHeight = document.getElementsByTagName("body")[0].clientHeight - stageTop + toolBarHeight;
        sidebar.style.height = sidebarHeight + "px";
    }
    
    //set position of toc button
    if ( (findPos(fitToWindow)[0]-220) > stageLeft ) {
        toc.style.left = (findPos(fitToWindow)[0]-205) + "px";
    } else {
        //if it is trying to appear before start of stageLeft, catch it
        toc.style.left = stageLeft + "px";
    }
    
    //set position of navigation buttons
    if ( (findPos(fitToWindow)[0]-390) > (stageLeft) ) {
        navButtons.style.left = (findPos(fitToWindow)[0]-390) + "px";
    } else {
        navButtons.style.left = stageLeft;
    }
    
    //if fit to window is depressed, release it on resize
    if (isFitToWindowSelected) {
        isFitToWindowSelected = false;
       btnFitToWindow.src = "/images/btnFitToWindow.gif";
        btnFitToWindow.style.cursor = "pointer";
    }

    // jQuery snippet to remove inline styles and apply custom styles
    var siteIDFromIndex=6;
    if(siteIDFromIndex==2 || siteIDFromIndex==5 || siteIDFromIndex==6)
    {
        if ($.browser.msie) {
            $("#toc").removeAttr("style").attr("style", "float:left;margin-left:40px;position:absolute;");
            $("#main_container").attr("style", "margin:0 auto; width:983px; text-align: left;");
        } else {
            $("#toc").removeAttr("style").attr("style", "float:left;margin-left:440px;position:absolute;");
            $("#main_container").attr("style", "margin:0 auto; width:1003px; text-align: left;");
        }
        $("#navButtons").removeAttr("style").attr("style", "float:left;position:static");
        $("#fitToWindow").removeAttr("style");
    }else{
       /* var toolbarfullwidth_in_js;
        var rightColumnWidth=$(window).width() - 298;
        if(rightColumnWidth>450){toolbarfullwidth_in_js=rightColumnWidth;}else{toolbarfullwidth_in_js=800;}
        if ($.browser.msie) {
            $("#toc").removeAttr("style").attr("style", "float:left;position:absolute;margin-left:" + (toolbarfullwidth - 508) + "px;");
            $("#navButtons").removeAttr("style").attr("style", "float:left;position:absolute;margin-left:" + ((toolbarfullwidth / 2) - 339) + "px;");
            $("#fitToWindow").removeAttr("style").attr("style", "float:left;position:absolute;margin-left:" + (toolbarfullwidth - 298) + "px;");
        }else{
            $("#toc").removeAttr("style").attr("style", "float:left;position:absolute;margin-left:" + (toolbarfullwidth_in_js-250) + "px;");
            $("#navButtons").removeAttr("style").attr("style", "float:left;position:absolute;margin-left:" + ((toolbarfullwidth_in_js/2)-100) + "px;");
            $("#fitToWindow").removeAttr("style").attr("style", "float:left;position:absolute;margin-left:" + (toolbarfullwidth_in_js-40) + "px;")
        }*/
    }
    //$("#ctl00_ContentPlaceHolder1_biStage").css({ width: '100%' });
    // End of jQuery snippet
}

function windowMouseMove(ev) {
    ev = ev || window.event;
    globalXPos = ev.clientX;
    globalYPos = ev.clientY;
}

function windowMouseWheel(ev) {
    var delta = 0;
    ev = ev || window.event;
    if (ev.wheelDelta) { //ie/opera
        delta = ev.wheelDelta/120; 
        if (window.opera) { delta = -delta; } //opera
    } else if (ev.detail) { //mozilla
        delta = -ev.detail/3;
    }

    //handles Firefox auto scrollwheel when moused over biStage
    if ( (delta) && (globalYPos >= stageTop) && (globalXPos >= stageLeft) ) {
        biStage.scrollTop = biStage.scrollTop - (delta*100);
        biScroll();
    }

    //handles Firefox auto scrollwheel when moused over left sidebar
    if ( (delta) && (globalYPos >= stageTop) && (globalXPos < stageLeft) ) {
        sidebar.scrollTop = sidebar.scrollTop - (delta*100);
    }

    if (ev.preventDefault) {
            ev.preventDefault();
    }
    ev.returnValue = false;
}

var arrBookPages = biStage.getElementsByTagName("div");
var arrBookImages = biStage.getElementsByTagName("img");

//build array of scroll heights
var arrPageHeight = [oBook.pages.length];
arrPageHeight[0] = 0;
for (i=0; i < oBook.pages.length; i++) {
    if (i===0) {
        arrPageHeight[i+1] = oBook.pages[i].imgH + 30;
    } else {
        arrPageHeight[i+1] = oBook.pages[i].imgH + 30 + arrPageHeight[i];
    }
}

// global pagination variables
var curPage = 0;
var startPage = 0;
var endPage = arrBookImages.length-1;

//Browse Inside specific event handlers
biStage.onmousedown = biMouseDown;
biStage.onmouseup = biMouseUp;
biStage.onmousemove = biMouseMove;
biStage.onscroll = biScroll;

function biMouseDown(ev){
	isMouseDown = true;
	ev = ev || window.event;

	startY = ev.clientY;
	startX = ev.clientX;
	
	//prevent not being able to click biStage into focus in IE
	if (is_ie) { this.focus(); }
	
	//prevent text selection Firefox
	if (typeof ev.preventDefault !== "undefined") { ev.preventDefault(); }
}

function biMouseMove(ev){
	ev = ev || window.event;
	
	if ((isMouseDown) && (startY < stageTop + stageHeight) && (startY >= stageTop) && (startX < stageLeft + stageWidth-17)) {
		biStage.scrollTop += startY - ev.clientY;
		biStage.scrollLeft += startX - ev.clientX;
		startY = ev.clientY;
		startX = ev.clientX;
		
		//firefox does not trigger scroll event so call it explicitly
		if (is_fx) { biScroll(); }
	}
}

function biMouseUp(ev) {
	isMouseDown = false;
}

function biScroll(ev) {
    checkLoadingRequests();
    
    //if current page is not last page of book,
    //and scroll is greater than or equal to start of next page,
    //and the next page has not been loaded yet,
    //load in next image 
    if ( (curPage < endPage) && (biStage.scrollTop >= (arrPageHeight[curPage+1]-stageHeight)) && (!oBook.pages[curPage+1].isLoaded) && (!arrPageRequests[curPage+1]) ) {
        arrPageRequests[curPage+1] = new BiPageRequest(curPage+1, curZoomPerc);
        arrPageRequests[curPage+1].getPageImage();
    }
    //if current page is not start of book, 
    //and scroll is less than end of previous page
    //and previous page has not been loaded yet
    //load in prevous image
    if ( (curPage > 0) && (biStage.scrollTop < (arrPageHeight[curPage]-30)) && (!oBook.pages[curPage-1].isLoaded) && (!arrPageRequests[curPage-1]) ) {
        arrPageRequests[curPage-1] = new BiPageRequest(curPage-1, curZoomPerc);
        arrPageRequests[curPage-1].getPageImage();
    }
    //add to page number at next 50% mark
    if ( (curPage < endPage) && (biStage.scrollTop >= (arrPageHeight[curPage]+(stageHeight*0.50))) ) {
        curPage++;
        
        //page numbering commented out for launch because data is out of synch
        //pageNumber.innerHTML = "Page " + oBook.pages[curPage].pNum;
    }
    //subtract from page number if scroll is above current 50%
    if ((curPage > 0) && (biStage.scrollTop < (arrPageHeight[curPage]-(stageHeight*0.50))) ) {
        curPage--;
        
        //page numbering commented out for launch because data is out of synch
        //pageNumber.innerHTML = "Page " + oBook.pages[curPage].pNum;
    }
    
    if ((curPage === 0) && (prevButtonsEnabled)) { disablePrevButtons(); } 
    if ((curPage > 0) && (!prevButtonsEnabled)) { enablePrevButtons(); }
    
    if ((curPage === endPage) && (nextButtonsEnabled)) { disableNextButtons(); }
    if ((curPage < endPage) && (!nextButtonsEnabled)) { enableNextButtons(); }
}

function initScroll(){
    if ( (biStage.scrollTop >= (arrPageHeight[curPage]-stageHeight)) && (!oBook.pages[curPage].isLoaded) && (!arrPageRequests[curPage]) ) {
        arrPageRequests[curPage] = new BiPageRequest(curPage, curZoomPerc);
        arrPageRequests[curPage].getPageImage();
    }
    
    //page numbering commented out for launch because data is out of synch
    //pageNumber.innerHTML = "Page " + oBook.pages[curPage].pNum;
}

function findPos(obj) {
    var curleft = 0; curtop = 0;
    if (obj.offsetParent) {
        curleft = obj.offsetLeft;
        curtop = obj.offsetTop;
        while (obj = obj.offsetParent) {
	        curleft += obj.offsetLeft;
	        curtop += obj.offsetTop;
        }
    }
    return [curleft,curtop];
}


// START TOC
	
//create rows in table of contents
for (y=0; y < oBook.pages.length; y++) {
    if (oBook.pages[y].pGrp !== "") {
        tocPanel.innerHTML += "<div class='tocRow' onmouseover='mouseOverTocRow(this)' onmouseout='mouseOutTocRow(this)' onclick='tocRowClick(this, " + y + ")'>" + oBook.pages[y].pGrp + "</div>";
    }
}

function tocRowClick(el, pageNum){
    goToPage(pageNum);
    el.className = "tocRow";
}

function mouseOverTocRow(el) {
    el.className = "tocRowOver";
}

function mouseOutTocRow(el) {
    el.className = "tocRow";
}

//register main TOC button events
btnToc.onclick = toggleTocMenu;
btnToc.onmouseover = mouseOverTocBtn;
btnToc.onmouseout = mouseOutTocBtn;

//handle document clicks
document.onclick = documentClick;

var isMenuOpen = false;

function toggleTocMenu() {
    if (!isMenuOpen) {
        btnToc.src = "/images/toc_selected.gif";
		tocStage.style.display = "block";
        isMenuOpen = true;
    } else {
        btnToc.src = "/images/toc.gif";
		tocStage.style.display = "none";
        isMenuOpen = false;        
    }
}

function hideTocMenu() {
    btnToc.src = "/images/toc.gif";
	tocStage.style.display = "none";
    isMenuOpen = false;
}

function mouseOverTocBtn() {
    if (isMenuOpen) {
        btnToc.src = "/images/toc_selected.gif";
    } else {
        btnToc.src = "/images/toc_over.gif";
    }
}

function mouseOutTocBtn() {
    if (!isMenuOpen) {
        btnToc.src = "/images/toc.gif";
    }
}

function documentClick (ev) {
    var targ;
    ev = ev || window.event;
    if (ev.target) { targ = ev.target; }
    else if (ev.srcElement) { targ = ev.srcElement; }
    if (targ.nodeType === 3) { // defeat Safari bug
        targ = targ.parentNode;
    }
    //hide toc menu when user clicks off
    if ( (targ.id !== "toc") && (targ.id !== "btnToc") && (targ.id !== "tocStage") && (targ.id !== "tocPanel") && (targ.id !== "tocNavigation") && (targ.id !== "tocUp") && (targ.id !== "tocDown") ) {
        hideTocMenu();
    }
}

// TOC Navigation Arrows
function toggleUpArrow(ev) {
    var imgPath;
    if (scrollPos === 0) {
        imgPath = this.src.substring(this.src.indexOf("/images"), this.src.length);
        if (imgPath !== "/images/up_disabled.gif") {
            this.src="/images/up_disabled.gif";
        }
    } else {
        ev = ev || window.event;
        if (ev.type === "mouseover") {
            this.src="/images/up_over.gif";
        } else if (ev.type === "mousedown") {
            this.src="/images/up_down.gif";
	    } else if (ev.type === "mouseup") {
            this.src="/images/up_over.gif";
        } else {
            this.src="/images/up.gif";
        }
    }
}

function toggleDownArrow(ev) {
    var imgPath;
    if (scrollPos >= (scrollEnd-scrollPos)) {
        imgPath = this.src.substring(this.src.indexOf("/images"), this.src.length);
        if (imgPath !== "/images/down_disabled.gif") {
            this.src="/images/down_disabled.gif";
        }
    } else {
        ev = ev || window.event;
        if (ev.type === "mouseover") {
            this.src="/images/down_over.gif";
        } else if (ev.type === "mousedown") {
            this.src="/images/down_down.gif";
	    } else if (ev.type === "mouseup") {
            this.src="/images/down_over.gif";
        } else {
            this.src="/images/down.gif";
        }
    }
}

// TOC Scrolling
var scrollPos = tocPanel.scrollTop;
var scrollStart = 0;
var scrollEnd = tocPanel.scrollHeight;

// TOC Menu Items
var menuItemHeight = 0;
if (arrTocRows.length !== 0) {
    menuItemHeight = arrTocRows[0].offsetHeight;
} 

var numOfRows = 10;
var scrollLength = menuItemHeight*numOfRows;
tocPanel.style.height = scrollLength + "px";
var scrollIncrement = 6;
var d, u;

function scrollDown() {
    if ( (scrollPos < scrollEnd) && (scrollPos < scrollStart+scrollLength) ) {
        scrollPos = scrollPos + scrollIncrement;
        tocPanel.scrollTop = scrollPos;
        d = setTimeout(scrollDown, 1);
    } else {
        scrollStart = tocPanel.scrollTop;
        clearTimeout(d);
       
        if (scrollPos > 0) { upArrow.src = "/images/up.gif"; upArrow.style.cursor = "pointer"; }
        if (scrollPos >= (scrollEnd-scrollPos)) { downArrow.src = "/images/down_disabled.gif"; downArrow.style.cursor = "default"; }
    }
}

function scrollUp() {
    if ( (scrollPos > 0) && (scrollPos > scrollStart-scrollLength) ) {
        scrollPos = scrollPos - scrollIncrement;
        tocPanel.scrollTop = scrollPos;
        u = setTimeout(scrollUp, 1);
    } else {
        scrollStart = tocPanel.scrollTop;
        clearTimeout(u);
        
        if (scrollPos === 0 ) { upArrow.src = "/images/up_disabled.gif"; upArrow.style.cursor = "default"; }
        if (scrollPos < scrollEnd) { downArrow.src = "/images/down.gif"; downArrow.style.cursor = "pointer"; }
    }
}

//register up arrow events
upArrow.onmouseover = toggleUpArrow;
upArrow.onmouseout = toggleUpArrow;
upArrow.onmousedown = toggleUpArrow;
upArrow.onmouseup = toggleUpArrow;
upArrow.onclick = scrollUp;

//set default cursor styles (for startup only)
upArrow.src = "/images/up_disabled.gif";
upArrow.style.cursor = "default";

//register down arrow events
downArrow.onmouseover = toggleDownArrow;
downArrow.onmouseout = toggleDownArrow;
downArrow.onmousedown = toggleDownArrow;
downArrow.onmouseup = toggleDownArrow;
downArrow.onclick = scrollDown;

//hide TOC in script - this is so that entire toc menu has loaded before turning display:none
hideTocMenu();

//call initScroll function to load in first image
initScroll();

// START TOOLBAR BUTTONS
//assign header button event handlers
//button handler functions are in common.js
for (b=0; b < arrHeadButtons.length; b++)
{
    arrHeadButtons[b].onmouseover = handleButton;
	arrHeadButtons[b].onmouseout = handleButton;
	arrHeadButtons[b].onmousedown = handleButton;
	arrHeadButtons[b].onmouseup = handleButton;
}

//assign toolbar button event handlers
for (b=0; b < arrButtons.length; b++)
{
	arrButtons[b].onmouseover = handleToolBarButton;
	arrButtons[b].onmouseout = handleToolBarButton;
	arrButtons[b].onmousedown = handleToolBarButton;
	arrButtons[b].onmouseup = handleToolBarButton;
}

//assign button event handlers to FitToWindow (it is now ouside of arrButtons array)
btnFitToWindow.onmouseover = handleToolBarButton;
btnFitToWindow.onmouseout = handleToolBarButton;
btnFitToWindow.onmousedown = handleToolBarButton;
btnFitToWindow.onmouseup = handleToolBarButton;

//set global on-off flag for buttons
var prevButtonsEnabled = true;
var nextButtonsEnabled = true;
var isFitToWindowSelected = false;

function disablePrevButtons() {
    btnPrev.src="/images/btnPrev_disabled.gif"; 
    btnPrev.style.cursor = "default";
    btnSkipFirst.src="/images/btnSkipFirst_disabled.gif";
    btnSkipFirst.style.cursor = "default";
    prevButtonsEnabled = false;
}

function enablePrevButtons() {
    btnPrev.src="/images/btnPrev.gif"; 
    btnPrev.style.cursor = "pointer";
    btnSkipFirst.src="/images/btnSkipFirst.gif";
    btnSkipFirst.style.cursor = "pointer";
    prevButtonsEnabled = true;
}

function disableNextButtons() {
    btnNext.src="/images/btnNext_disabled.gif";
    btnNext.style.cursor = "default";
    btnSkipLast.src="/images/btnSkipLast_disabled.gif";
    btnSkipLast.style.cursor = "default";
    nextButtonsEnabled = false;
}

function enableNextButtons() {
    btnNext.src="/images/btnNext.gif";
    btnNext.style.cursor = "pointer";
    btnSkipLast.src="/images/btnSkipLast.gif";
    btnSkipLast.style.cursor = "pointer";
    nextButtonsEnabled = true;
}

//check buttons on startup
if (curPage === 0) { disablePrevButtons(); }
if (curPage === endPage) { disableNextButtons(); }

function resetPageHeight(pageHeight, pageNum){
    arrPageHeight[0] = 0;
    if (pageNum===0) {
        arrPageHeight[pageNum+1] = pageHeight+ 30;
    } else {
        arrPageHeight[pageNum+1] = pageHeight + 30 + arrPageHeight[pageNum];
    }
}

//commented out for launch
//btnZoomIn.onclick = fnZoomIn;
//btnZoomOut.onclick = fnZoomOut;
btnFitToWindow.onclick = fnFitToWindow;

function fnZoomIn() {

    var tempPage = curPage;
    
    if (curZoomLevel < arrZoomInc.length-1) {
        curZoomLevel++;
        curZoomPerc = arrZoomInc[curZoomLevel];
        
        //clear out existing array of page heights and create a new one
        arrPageHeight = null;
        arrPageHeight = [oBook.pages.length];
        
        for (t=0; t < arrBookImages.length; t++) 
        {
            arrBookImages[t].width = Math.round(oBook.pages[t].imgW*curZoomPerc);
            arrBookImages[t].height = Math.round(oBook.pages[t].imgH*curZoomPerc);
            arrBookPages[t].style.width = Math.round(oBook.pages[t].imgW*curZoomPerc);
            resetPageHeight(Math.round(oBook.pages[t].imgH*curZoomPerc), t);
        }
        
        goToPage(tempPage);
        
        //zoom out is available so show button
        btnZoomOut.src = "/images/btnZoomOut.gif";
        btnZoomOut.style.cursor = "pointer";
        
        //reset fit to window button style to enabled
        isFitToWindowSelected = false;
        btnFitToWindow.src = "/images/btnFitToWindow.gif";
        btnFitToWindow.style.cursor = "pointer";
    }
    
    //set button styles
    if (curZoomLevel === arrZoomInc.length-1) {
        btnZoomIn.src = "/images/btnZoomIn_disabled.gif";
        btnZoomIn.style.cursor = "default";
    } else {
        btnZoomIn.src = "/images/btnZoomIn.gif";
        btnZoomIn.style.cursor = "pointer";
    }
}

function fnZoomOut() {
    
    var tempPage = curPage;
    
    if (curZoomLevel > 0) {
        curZoomLevel--;
        curZoomPerc = arrZoomInc[curZoomLevel];
        for (t=0; t < arrBookImages.length; t++) 
        {
            arrBookImages[t].width = Math.round(oBook.pages[t].imgW*curZoomPerc);
            arrBookImages[t].height = Math.round(oBook.pages[t].imgH*curZoomPerc);
            arrBookPages[t].style.width = Math.round(oBook.pages[t].imgW*curZoomPerc);
            resetPageHeight(Math.round(oBook.pages[t].imgH*curZoomPerc), t);
        }

        goToPage(tempPage);
        
        //zoom in is available, so show button
        btnZoomIn.src = "/images/btnZoomIn.gif";
        btnZoomIn.style.cursor = "pointer";

        //reset fit to window button style to enabled
        isFitToWindowSelected = false;
        btnFitToWindow.src = "/images/btnFitToWindow.gif";
        btnFitToWindow.style.cursor = "pointer";
    }
    
    //set button styles
    if (curZoomLevel === 0) {
        btnZoomOut.src = "/images/btnZoomOut_disabled.gif";
        btnZoomOut.style.cursor = "default";
    } else {
        btnZoomOut.src = "/images/btnZoomOut.gif";
        btnZoomOut.style.cursor = "pointer";
    }
}

function fnFitToWindow() {
    var aspectRatio, zoomImgArea, origImgArea, zPerc, prevZoomImgArea;
    
    if (isFitToWindowSelected) {
        isFitToWindowSelected = false;

        //set button style to enabled
        btnFitToWindow.src = "/images/btnFitToWindow.gif";
        btnFitToWindow.style.cursor = "pointer";
    
        curZoomLevel = 4;
        curZoomPerc = arrZoomInc[curZoomLevel];
        for (t=0; t < arrBookImages.length; t++) 
        {
            arrBookImages[t].width = Math.round(oBook.pages[t].imgW*curZoomPerc);
            arrBookImages[t].height = Math.round(oBook.pages[t].imgH*curZoomPerc);
            arrBookPages[t].style.width = Math.round(oBook.pages[t].imgW*curZoomPerc);
            resetPageHeight(Math.round(oBook.pages[t].imgH*curZoomPerc), t);
        }
        
        //commented out for launch
        //btnZoomIn.src = "/images/btnZoomIn.gif";
        //btnZoomIn.style.cursor = "pointer";
        //btnZoomOut.src = "/images/btnZoomOut.gif";
        //btnZoomOut.style.cursor = "pointer";

    } else {
    
        isFitToWindowSelected = true;
        
        //set button style to disabled
        btnFitToWindow.src = "/images/btnFitToWindow_down.gif";
        btnFitToWindow.style.cursor = "default";
        
        for (t=0; t < arrBookImages.length; t++)
        {
            aspectRatio = arrBookImages[t].width/arrBookImages[t].height;
            arrBookImages[t].width = Math.round(aspectRatio*stageHeight);
            arrBookImages[t].height = stageHeight;
            arrBookPages[t].style.width = Math.round(aspectRatio*stageHeight);
            
            //now figure out what the corresponding current zoom level is
            origImgHeight = oBook.pages[t].imgH;
            zoomImgHeight = arrBookImages[t].height;
            zPerc = zoomImgHeight/origImgHeight;
            
            //get the previous zoomed image's area
            if (t===0) {
                prevZoomHeight = arrBookImages[t].height;
            } else {
                prevZoomHeight = arrBookImages[t-1].height;
            }
            
            //update the zoom percentage if the next image has a larger area
            if (zoomImgHeight > prevZoomHeight) {
                zPerc = zoomImgHeight/origImgHeight;
            }
        }
        
        //set the current zoom to the smallest level
        curZoomLevel = 0;
        
        //loop through zoom increments and set zoom level            
        for (z=0; z < arrZoomInc.length; z++) {
            if (zPerc > arrZoomInc[z]) {
                curZoomLevel = z;
            }
        }
        
        //set global zoom percentage
        curZoomPerc = zPerc;
        
        //commented out for launch
        //if (curZoomLevel === arrZoomInc.length-1) {
        //    btnZoomIn.src = "/images/btnZoomIn_disabled.gif";
        //    btnZoomIn.style.cursor = "default";
        //    btnZoomOut.src = "/images/btnZoomOut.gif";
        //    btnZoomOut.style.cursor = "pointer";
        //} else if (curZoomLevel === 0) {
        //    btnZoomOut.src = "/images/btnZoomOut_disabled.gif";
        //    btnZoomOut.style.cursor = "default";
        //    btnZoomIn.src = "/images/btnZoomIn.gif";
        //    btnZoomIn.style.cursor = "pointer";
        //} else if ( (curZoomLevel < arrZoomInc.length-1) && (curZoomLevel > 0) ) {
        //    btnZoomIn.src = "/images/btnZoomIn.gif";
        //    btnZoomIn.style.cursor = "pointer";
        //    btnZoomOut.src = "/images/btnZoomOut.gif";
        //    btnZoomOut.style.cursor = "pointer";
        //}
        
        for (t=0; t < arrBookImages.length; t++){
             resetPageHeight(Math.round(oBook.pages[t].imgH*curZoomPerc), t);
        }
    }
    goToPage(curPage);
}

function goToPage(pageNum) {
    var tempScroll = biStage.scrollTop;
    
    if (pageNum < 0) { pageNum = 0;}
    if (pageNum > oBook.pages.length-1){ pageNum = oBook.pages.length-1; }
    curPage = pageNum;
    
    biStage.scrollTop = arrPageHeight[pageNum];
    
    //check to see if scroll was updated after scrollTop changed
    if (tempScroll === biStage.scrollTop)
    {
        //value was the same, so call function (for case of first image)
        biScroll();
    }
    
    //page numbering commented out for launch because data is out of synch
    //pageNumber.innerHTML = "Page " + oBook.pages[pageNum].pNum;

    //final check to make sure image has loaded (this is for skip to first or last pages)
    if ( (!oBook.pages[curPage].isLoaded) && (!arrPageRequests[curPage]) ) {
        arrPageRequests[curPage] = new BiPageRequest(curPage, curZoomPerc);
        arrPageRequests[curPage].getPageImage();
    }
    
    //and get next image too (in case user is zoomed out)
    //if ( ((curPage+1) < endPage) && (!oBook.pages[curPage+1].isLoaded) && (!arrPageRequests[curPage+1]) ) {
    //    arrPageRequests[curPage+1] = new BiPageRequest(curPage+1, curZoomPerc);
    //    arrPageRequests[curPage+1].getPageImage();
    //}
}

function getPageIndex(pageSequence){
    for (i=0; i < oBook.pages.length; i++) {
        if (oBook.pages[i].pNum === parseInt(pageSequence,0)) {
            return i;
        }
    }
    return null;
}

function goToPageSequence(pageSequence){
    var pageIndex = getPageIndex(pageSequence);
    if (pageIndex !== null) {
        goToPage(pageIndex);
    }
}

btnNext.onclick = function(){
    if (curPage < endPage) {
        goToPage(curPage+1);
    }
};

btnPrev.onclick = function(){
    if (curPage > startPage) {
       goToPage(curPage-1);
    }
};

btnSkipFirst.onclick = function(){
    curPage=0;
    goToPage(startPage);
};

btnSkipLast.onclick = function(){
    curPage=endPage;
    //call webtrends only if button is enabled
    goToPage(endPage);
};



btnWidget.onclick = function(){
    document.location = "faq.aspx?isbn13=9780062083029";    
};



btnEmail.onclick = function(){
    document.location = "mailto:?subject=Start%20reading%20Fancy%20Nancy%20and%20the%20Too-Loose%20Tooth%20By%20Jane%20O'Connor%20Illustrated%20by%20Robin%20Preiss%20Glasser%20&body=I%20thought%20you'd%20be%20interested%20in%20this.%20Click%20on%20the%20link%20to%20Browse%20Inside%20and%20start%20reading%20the%20book.%0d%0a%0d%0ahttp://browseinside.harpercollins.ca/index.aspx?isbn13=9780062083029%26pg=" + oBook.pages[curPage].pNum;    
};



btnFeedback.onclick = function(){
    window.open("http://www.harpercollins.com/features/browseinside/feedback.aspx");
};

// handle specific page requests
var pageQS = queryString("pg");
if (pageQS !== "false") {
    goToPageSequence(pageQS);
}

window.onload = function() {
    //defeat safari bug that loads incorrect page height/widths when page initializes
    if (is_safari) { 
        //stageWidth = document.getElementsByTagName("body")[0].clientWidth - sidebarWidth;   
        stageWidth=bodyWidthValue(6);
        stageHeight = document.getElementsByTagName("body")[0].clientHeight - stageTop;
        biStage.style.width = stageWidth + "px";
        biStage.style.height = stageHeight + "px";
        sidebarHeight = document.getElementsByTagName("body")[0].clientHeight - stageTop + toolBarHeight;
        sidebar.style.height = sidebarHeight + "px";
    }
    //show the page after everything has loaded
    document.getElementById("biTable").style.visibility = "visible";
};