/*
This file contains all other user interaction functions:
switching to the 3 column layout, switching to the 1 column
layout, increasing and decreasing the font, setting the 
window resize, etc.
*/

var classFix;
if (document.all){
	classFix = "className";
} else {
	classFix = "class";
}

// these values come from the cookie
var columnMode = 2;

// set some defaults values
var originalHeight;
var lineHeight = 16;
var currentPos = 0;

// use these values to manipulate the width of the text columns
// col3Width is used in the 3 column layout and col1Width is 
// used in the 1 column layout.
var col3Width = 284;

// use this number to manipulate the height of the article text box
// it is counter intuitive: smaller is taller, bigger is shorter
var heightOfColumns = 700;
var heightB;

// returns the height of the current window
function getHeight(obj){
	if (obj == "window"){
		if (window.innerHeight){
			return window.innerHeight;
		} else {
			return document.getElementById("bodyNode").offsetHeight;
		}
	} else {
		obj = document.getElementById(obj);
		if (obj.offsetHeight){
			return obj.offsetHeight;
		}
	}
}
	
// makes the columns and copies the text node into the newly
// created columns ac is the div holding the cloned node - at
function articleSetup(){
	var fontSize = 12;
    
    var cv1 = 12;
	var parentDiv = document.getElementById("articleParent");
	var currentPos = 0;
	for (var i = 0; i < columnMode; i++){
		var col = document.createElement("div");
		col.setAttribute("id", "ac" + i);
		//col.setAttribute("class", "artCol");
		col.setAttribute(classFix, "artCol");
		parentDiv.appendChild(col);
		var obj = document.getElementById("articleBody");
		var artText = obj.cloneNode(true);
		artText.setAttribute("id", "at" + i);
		artText.style.display = "block";
		artText.style.top = "0px";
		artText.style.fontSize = fontSize + "px";
		artText.style.lineHeight = lineHeight + "px";
		col.appendChild(artText);		
	}
}

// moves the columns into position, but adjust the top
function layoutArticles(){	
	var parentHeight = getHeight("articleParent");
	for (var i = 0; i < columnMode; i++){
		var obj = document.getElementById("at" + i);
		//make sure at least 2 rows of article text are available 
		if (parentHeight > (2 * lineHeight)){
			obj.style.top = -1 * (parentHeight * (i + currentPos));
		}
	}
	articlePages();
}

// resets the article to the first "page"
function resetArticle(){
	currentPos = 0;
	layoutArticles();
}

// returns the snap to align article; this adjusts the height of the 
// article window with a number divisible by line height. the minium 
// number of rows is 10
function setSnap(mod){
	if (mod == null){
		mod = 0;
	}
	var snap = lineHeight * Math.round((getHeight("window") - mod) / lineHeight);	
	if (snap < (lineHeight * 10)){
		snap = lineHeight * 10;
		if (window.scrollTo){
			window.scrollTo(0, 75);
		}
	} else if (window.scrollTo){
		window.scrollTo(0, 0);
	}
	return snap;
}

// clips the parent layer to the defined visible area
// if space allows include bottom, otherwise clip out most of bottom
function setArticleHeightNew(){
	if (columnMode > 1){
		if (document.getElementById("articleBody") != null){
			//document.getElementById("articleParent").style.height = setSnap(heightOfColumns);	
			
			/*document.getElementById('articleBody').style.display='visible';
			var height=document.getElementById('articleBody').offsetHeight;//getHeight("articleBody");
			document.getElementById('articleBody').style.display='none';*/
			//alert('!!!'+heightB+'!');
			h=heightB.replace('px','');
			var m=Math.round(h/2); 
			var i=0;
			while (m>i) i=i+lineHeight;			
			document.getElementById("articleParent").style.height = i+'px';
			var tHeight = getHeight("at1");
			parentHeight = getHeight("articleParent");
			//parentHeight=Math.round(tHeight);
			//alert(getHeight("articleParent")+'...'+tHeight+'...'+parentHeight);
			//check to make sure page is still visible
			while ((parentHeight * (currentPos + (columnMode - 1))) > tHeight && currentPos > 0){
				currentPos = currentPos - 1;
			}
		}
	}
}

// returns the number of screens an article spans, ie the number of pages
function articlePages(){
	var parentHeight = getHeight("articleParent");
	var tHeight = getHeight("at1");
	var totalColumns = tHeight / parentHeight;
	var totalPages = Math.ceil(totalColumns);
	//alert('!'+totalColumns+'  '+totalPages);
	var tPos = (currentPos + columnMode) / columnMode;
	var pagesTotal = Math.ceil(totalPages / columnMode);
	var pagesCurrent = Math.round(tPos);
	var obj = document.getElementById("tc_page_nav_middle");
	obj.innerHTML = "" + pagesCurrent + " of " + pagesTotal;
    
    // button activation/deactivation
    var prevButtonBG = document.getElementById("tc_prev_button_bg");
    var prevButtonText = document.getElementById("tc_prev_button_text");
    var nextButtonBG = document.getElementById("tc_next_button_bg");
    var nextButtonText = document.getElementById("tc_next_button_text");
    if (pagesTotal > 1) {
        if (pagesCurrent == 1) {
            // activate next button
            nextButtonText.style.color = "#000";
            nextButtonBG.onmouseover = function () {
                //nextButtonBG.style.backgroundColor = "#e5e5e5";
                nextButtonBG.style.cursor = "pointer";
            }
            nextButtonBG.onmouseout = function () {
                nextButtonBG.style.backgroundColor = "";
            }
            nextButtonBG.onclick = function () { nextPage(); }
            // deactivate prev button
            prevButtonText.style.color = "#ccc";
            prevButtonBG.onmouseover = function () {
                prevButtonBG.style.backgroundColor = "";
                prevButtonBG.style.cursor = "";
            }
        } 
        
        if (pagesCurrent > 1 && (pagesCurrent <= pagesTotal)) {
            // activate prev button
            prevButtonText.style.color = "#000";
            prevButtonBG.onmouseover = function () {
                //prevButtonBG.style.backgroundColor = "#e5e5e5";
                prevButtonBG.style.cursor = "pointer";
            }
            prevButtonBG.onmouseout = function () {
                prevButtonBG.style.backgroundColor = "";
            }
            prevButtonBG.onclick = function () { prevPage(); }
            if (pagesCurrent == pagesTotal) {
                // deactivate next button
                nextButtonText.style.color = "#ccc";
                nextButtonBG.onmouseover = function () {
                    nextButtonBG.style.backgroundColor = "";
                    nextButtonBG.style.cursor = "";
                }
            } else {
                // activate next button
                nextButtonText.style.color = "#000";
                nextButtonBG.onmouseover = function () {
                   // nextButtonBG.style.backgroundColor = "#e5e5e5";
                    nextButtonBG.style.cursor = "pointer";
                }
                nextButtonBG.onmouseout = function () {
                    nextButtonBG.style.backgroundColor = "";
                }
                nextButtonBG.onclick = function () { nextPage(); }
            }
        }
    	}
	else {
			document.getElementById('tc_prev_button_bg').style.visibility='hidden';
			document.getElementById('tc_page_nav_middle').style.visibility='hidden';
			document.getElementById('tc_next_button_bg').style.visibility='hidden';
		}
}




// adjusts the article to display the next page
function nextPage(){
	tHeight = getHeight("at1")
	var parentHeight = getHeight("articleParent");
	// check to make sure page is still visible 
	if ((parentHeight * (currentPos + columnMode)) < tHeight){
		currentPos = currentPos + columnMode;
	}
	layoutArticles();
}

// adjusts the article to display the previous page
function prevPage(){
	currentPos = currentPos - columnMode;
	if (currentPos < 0){
		currentPos = 0;
	}
	layoutArticles();
}

// switches to three Column mode
function threeColumn(){
	var fontSize = 12;
    var cv1 = 12;
	currentPos = 0;
	//columnMode = 2;
	colWidth = col3Width;

	if (fontSize > 18){
		fontSize = 18;
	}
	var obj1 = document.getElementById("at0");
	obj1.style.zIndex = 5;
	obj1.style.display = "block";
	obj1.style.width = colWidth;
	obj1.style.left = 0;
	
	var obj2 = document.getElementById("at1");

	obj2.style.zIndex = 5;
	obj2.style.display = "block";
	obj2.style.width = colWidth;
	obj2.style.left = colWidth + 20;

	/*var obj3 = document.getElementById("at2");

	obj3.style.zIndex = 5;
	obj3.style.display = "block";
	obj3.style.width = colWidth;
	obj3.style.left = 2 * (colWidth + 20);*/

}

function initArticleNew(height){
	heightB=height;
	if (document.getElementById("articleBody") != null){
		articleSetup();
		setArticleHeightNew();
		threeColumn();
		layoutArticles();
	} else {
		//alert("Can not find articleBody node");
	}
}



// adjust article layout when the window is resized
function windowResize(){
	setArticleHeightNew();
	layoutArticles();
}
window.onresize = windowResize;