/**********************************
          GLOBAL VARIABLES
***********************************/
// pre-cache art files and sizes for widget styles and spacers
// (all images must have same height/width)
var collapsedWidget = new Image(20, 16);
collapsedWidget.src = "oplus.gif";
var collapsedWidgetStart = new Image(20, 16);
collapsedWidgetStart.src = "oplusStart.gif";
var collapsedWidgetEnd = new Image(20, 16);
collapsedWidgetEnd.src = "oplusEnd.gif";
var expandedWidget = new Image(20, 16);
expandedWidget.src = "ominus.gif";
var expandedWidgetStart = new Image(20, 16);
expandedWidgetStart.src = "ominusStart.gif";
var expandedWidgetEnd = new Image(20, 16);
expandedWidgetEnd.src = "ominusEnd.gif";
var nodeWidget = new Image(20, 16);
nodeWidget.src = "onode.gif";
var nodeWidgetEnd = new Image(20, 16);
nodeWidgetEnd.src = "onodeEnd.gif";
var emptySpace = new Image(20, 16);
emptySpace.src = "oempty.gif";
var chainSpace = new Image(20, 16);
chainSpace.src = "ochain.gif";

// miscellaneous globals
var widgetWidth = "20";
var widgetHeight = "16";
var currState = "";
var displayTarget = "contentFrame";

/**********************************
           DATA COLLECTIONS
***********************************/
var expansionState = "";
// constructor for outline item objects
function outlineItem(text, uri) {
    this.text = text;
    this.uri = uri;
}
var olData = {childNodes:
             [{item:new outlineItem("Zur Person"),
               childNodes:
                   [{item:new outlineItem("Geburtstage")},
                    {item:new outlineItem("Leben")},
                    {item:new outlineItem("Ort", "Probe.html")}
                    ]},
	      {item:new outlineItem("Zu Projekten"),
               childNodes:
                   [{item:new outlineItem("Kata", "Projekte/Kata_Diplom/Kata_Diplom.html")},
                    {item:new outlineItem("Olli-Nissen", "Projekte/OlliMolli/renderings.html")},
                    {item:new outlineItem("Prüfungen"),
					 childNodes:
					     [{item:new outlineItem("Stadtplanung")},
					      {item:new outlineItem("Gebäudekunde", "Projekte/Pruefung/Gebaeudekunde/RahmenGliederung.html")}
					     ]},
		    {item:new outlineItem("Pfefferberg", "http://www.viellieb.org/Version2_0/Projekte/Pfefferberg/Pfefferbergstart.html"),
			    childNodes:
			    	[{item:new outlineItem("Inhalt", "Projekte/Pfefferberg/Inhalt.html")},
				 {item:new outlineItem("These", "Projekte/Pfefferberg/these/denkmal.html")},
				 {item:new outlineItem("Geschichte"),
					 childNodes:
					     [{item:new outlineItem("1841-1886")},
					      {item:new outlineItem("1887-1920")},
					      {item:new outlineItem("1921-1989")},
					      {item:new outlineItem("1990-2002")}
					     ]},
				 {item:new outlineItem("Ist-Soll"),
					 childNodes:
					     [{item:new outlineItem("Ver. Pfefferwerk")},
					      {item:new outlineItem("Akira Ikeda Gallery")},
					      {item:new outlineItem("Entwurf")},
					      {item:new outlineItem("Denkmalpflege")}
					     ]},
				 {item:new outlineItem("Bewertung"),
					 childNodes:
					     [{item:new outlineItem("Vergleichsbauten")},
					      {item:new outlineItem("Die Bauwerke"),
						      	childNodes:
							    [{item:new outlineItem("Flaschenkeller")},
							     {item:new outlineItem("Kesselhaus")},
							     {item:new outlineItem("Biergarten")},
							     {item:new outlineItem("Kellergewölbe")}
					      		    ]}
					     ]},
				 {item:new outlineItem("Befund")}
				]},
                    {item:new outlineItem("Olli-Nissen", "Projekte/OlliMolli/renderings.html")},
                    {item:new outlineItem("WAS_SAGEN!?", "Projekte/wassagen/Anfang.html")}
                    ]},	
              {item:new outlineItem("Zu Pfaden"),
               childNodes:
                   [{item:new outlineItem("MacOSX", "Pfade/macosx.html")},
                    {item:new outlineItem("Netzstättenhelfer", "Pfade/helfer.html")},
                    {item:new outlineItem("Informationen", "Pfade/informationen.html")},
                    {item:new outlineItem("Leben", "Pfade/leben.html")},
                    {item:new outlineItem("Geschichte", "Pfade/geschichte.html")},
                    {item:new outlineItem("Musik", "Pfade/musik.html")},
                    {item:new outlineItem("Grafik/Design", "Pfade/grafik.html")},
                    {item:new outlineItem("Konsum", "Pfade/konsum.html")},
                    {item:new outlineItem("Rezepte", "Pfade/rezepte.html")},
                    {item:new outlineItem("Freunde", "Pfade/freunde.html")},
                    {item:new outlineItem("Danke", "Pfade/danke.html")}
                   ]}
              ]};

          
          


/**********************************
  TOGGLE DISPLAY AND ICONS
***********************************/
// invert item state (expanded to/from collapsed)
function swapState(currState, currVal, n) {
    var newState = currState.substring(0,n);
    newState += currVal ^ 1 // Bitwise XOR item n;
    newState += currState.substring(n+1,currState.length);
    return newState;
}

// retrieve matching version of 'minus' images
function getExpandedWidgetState(imgURL) {
    if (imgURL.indexOf("Start") != -1) {
        return expandedWidgetStart.src;
    }
    if (imgURL.indexOf("End") != -1) {
        return expandedWidgetEnd.src;
    }
    return expandedWidget.src;
}

// retrieve matching version of 'plus' images
function getCollapsedWidgetState(imgURL) {
    if (imgURL.indexOf("Start") != -1) {
        return collapsedWidgetStart.src;
    }
    if (imgURL.indexOf("End") != -1) {
        return collapsedWidgetEnd.src;
    }
    return collapsedWidget.src;
}

// toggle an outline mother entry, storing new state value;
// invoked by onclick event handlers of widget image elements
function toggle(img, blockNum) {
    var newString = "";
    var expanded, n;
    // modify state string based on parameters from IMG
    expanded = currState.charAt(blockNum);
    currState = swapState(currState, expanded, blockNum);
    // dynamically change display style
    if (expanded == "0") {
        document.getElementById("OLBlock" + blockNum).style.display = "block";
        img.src = getExpandedWidgetState(img.src);
    } else {
        document.getElementById("OLBlock" + blockNum).style.display = "none";
        img.src = getCollapsedWidgetState(img.src);
    }
}

function expandAll() {
    var newState = "";
    while (newState.length < currState.length) {
        newState += "1";
    }
    currState = newState;
    initExpand();
}

function collapseAll() {
    var newState = "";
    while (newState.length < currState.length) {
        newState += "0";
    }
    currState = newState;
    initExpand();
}

/*********************************
   OUTLINE HTML GENERATION
**********************************/
// apply default expansion state from outline's header
// info to the expanded state for one element to help 
// initialize currState variable
function calcBlockState(n) {
    // get default expansionState data
    var expandedData = (expansionState.length > 0) ? expansionState.split(",") : null;
    if (expandedData) {
        for (var j = 0; j < expandedData.length; j++) {
            if (n == expandedData[j] - 1) {
                return "1";
            }
        }
    }
    return "0";
}

// counters for reflexive calls to drawOutline()
var currID = 0;
var blockID = 0;
// generate HTML for outline
function drawOutline(ol, prefix) {
    var output = "";
    var nestCount, link, nestPrefix, lastInnerNode;
    prefix = (prefix) ? prefix : "";
    for (var i = 0; i < ol.childNodes.length ; i++) {
        nestCount = (ol.childNodes[i].childNodes) ? ol.childNodes[i].childNodes.length : 0;
        output += "<div class='OLRow' id='line" + currID++ + "'>\n";
        if (nestCount > 0) {
            output += prefix;
            output += "<img id='widget" + (currID-1) + "' src='" + ((i == ol.childNodes.length-1 && blockID != 0) ? collapsedWidgetEnd.src : (blockID == 0) ? collapsedWidgetStart.src : collapsedWidget.src);
            output += "' height=" + widgetHeight + " width=" + widgetWidth;
            output += " title='Drüberfahren zum öffnen und schließen der Struktur.' onmouseover='toggle(this," + blockID + ")'>&nbsp;";
            link =  (ol.childNodes[i].item.uri) ? ol.childNodes[i].item.uri : "";
            if (link) {
                output += "<a href='" + link + "' class='itemTitle' title='" + 
                link + "' target='" + displayTarget + "'>" ;
            } else {
                output += "<a class='itemTitle' title='" + link + "'>";
            }
            output += "<span style='position:relative; top:-3px; height:11px'>" + ol.childNodes[i].item.text + "</span></a>";
            currState += calcBlockState(currID-1);
            output += "<span class='OLBlock' blocknum='" + blockID + "' id='OLBlock" + blockID++ + "'>";
            nestPrefix = prefix;
            nestPrefix += (i == ol.childNodes.length - 1) ? 
                       "<img src='" + emptySpace.src + "' height=" + widgetHeight + " width=" + widgetWidth + ">" :
                       "<img src='" + chainSpace.src + "' height=" + widgetHeight + " width=" + widgetWidth + ">"
            output += drawOutline(ol.childNodes[i], nestPrefix);
            output += "</span></div>\n";
        } else {
            output += prefix;
            output += "<img id='widget" + (currID-1) + "' src='" + ((i == ol.childNodes.length - 1) ? nodeWidgetEnd.src : nodeWidget.src);
            output += "' height=" + widgetHeight + " width=" + widgetWidth + ">";
            link =  (ol.childNodes[i].item.uri) ? ol.childNodes[i].item.uri : "";
            if (link) {
                output += "&nbsp;<a href='" + link + "' class='itemTitle' title='" + 
                link + "' target='" + displayTarget + "'>";
            } else {
                output += "&nbsp;<a class='itemTitle' title='" + link + "'>";
            }
            output += "<span style='position:relative; top:-3px; height:11px'>" + ol.childNodes[i].item.text + "</span></a>";
            output += "</div>\n";
        }
    }
    return output;
}

/*********************************
     OUTLINE INITIALIZATIONS
**********************************/
// expand items set in expansionState var, if any
function initExpand() {
    for (var i = 0; i < currState.length; i++) {
        if (currState.charAt(i) == 1) {
            document.getElementById("OLBlock" + i).style.display = "block";
        } else {
            document.getElementById("OLBlock" + i).style.display = "none";
        }
    }
}

// initialize first time -- invoked onload
function initExpMenu(xFile) {
    // wrap whole outline HTML in a span
    var olHTML = "<span id='renderedOL'>" + drawOutline(olData) + "</span>";
    // throw HTML into 'content' div for display
    document.getElementById("content").innerHTML = olHTML;
    initExpand();
}