/*
 	 Copyright (c) 2007, iUI Project Members
	 See LICENSE.txt for licensing terms
 */


(function() {

var slideSpeed = 20;
var slideInterval = 0;

var currentPage = null;
var currentDialog = null;
var currentWidth = 0;
var currentHash = location.hash;
var hashPrefix = "#_";
var pageHistory = [];
var newPageCount = 0;
var checkTimer;

// *************************************************************************************************

window.iui =
{
	showPage: function(page, backwards)
	{
		if (page)
		{
			if (currentDialog)
			{
				currentDialog.removeAttribute("selected");
				currentDialog = null;
			}

			if (hasClass(page, "dialog"))
				showDialog(page);
			else
			{
				var fromPage = currentPage;
				currentPage = page;

				if (fromPage)
					setTimeout(slidePages, 0, fromPage, page, backwards);
				else
					updatePage(page, fromPage);
			}
		}
	},

	showPageById: function(pageId)
	{
		var page = $(pageId);
		if (page)
		{
			var index = pageHistory.indexOf(pageId);
			var backwards = index != -1;
			if (backwards)
				pageHistory.splice(index, pageHistory.length);

			iui.showPage(page, backwards);
		}
	},

	showPageByHref: function(href, args, method, replace, cb)
	{
		var req = new XMLHttpRequest();
		req.onerror = function()
		{
			if (cb)
				cb(false);
		};
		
		req.onreadystatechange = function()
		{
			if (req.readyState == 4)
			{
				if (replace)
					replaceElementWithSource(replace, req.responseText);
				else
				{
					var frag = document.createElement("div");
					frag.innerHTML = req.responseText;
					iui.insertPages(frag.childNodes);
				}
				if (cb)
					setTimeout(cb, 1000, true);
			}
		};

		if (args)
		{
			req.open(method || "GET", href, true);
			req.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
			req.setRequestHeader("Content-Length", args.length);
			req.send(args.join("&"));
		}
		else
		{
			req.open(method || "GET", href, true);
			req.send(null);
		}
	},
	
	insertPages: function(nodes)
	{
		var targetPage;
		for (var i = 0; i < nodes.length; ++i)
		{
			var child = nodes[i];
			if (child.nodeType == 1)
			{
				if (!child.id)
					child.id = "__" + (++newPageCount) + "__";

				var clone = $(child.id);
				if (clone)
					clone.parentNode.replaceChild(child, clone);
				else
					document.body.appendChild(child);

				if (child.getAttribute("selected") == "true" || !targetPage)
					targetPage = child;
				
				--i;
			}
		}

		if (targetPage)
			iui.showPage(targetPage);
	},

	getSelectedPage: function()
	{
		for (var child = document.body.firstChild; child; child = child.nextSibling)
		{
			if (child.nodeType == 1 && child.getAttribute("selected") == "true")
				return child;
		}	
	}	
};

// *************************************************************************************************

addEventListener("load", function(event)
{
	var page = iui.getSelectedPage();
	if (page)
		iui.showPage(page);

	setTimeout(preloadImages, 0);
	setTimeout(checkOrientAndLocation, 0);
	checkTimer = setInterval(checkOrientAndLocation, 300);
}, false);
	
addEventListener("click", function(event)
{
	var link = findParent(event.target, "a");
	if (link)
	{
		function unselect() { link.removeAttribute("selected"); }
		
		if (link.href && link.hash && link.hash != "#")
		{
			link.setAttribute("selected", "true");
			iui.showPage($(link.hash.substr(1)));
			setTimeout(unselect, 500);
		}
		else if (link == $("backButton"))
			history.back();
		else if (link.getAttribute("type") == "submit")
			submitForm(findParent(link, "form"));
		else if (link.getAttribute("type") == "cancel")
			cancelDialog(findParent(link, "form"));
		else if (link.target == "_replace")
		{
			link.setAttribute("selected", "progress");
			iui.showPageByHref(link.href, null, null, link, unselect);
		}
		else if (!link.target)
		{
			link.setAttribute("selected", "progress");
			iui.showPageByHref(link.href, null, null, null, unselect);
		}
		else
			return;
		
		event.preventDefault();
	}
}, true);

addEventListener("click", function(event)
{
	var div = findParent(event.target, "div");
	if (div && hasClass(div, "toggle"))
	{
		div.setAttribute("toggled", div.getAttribute("toggled") != "true");
		event.preventDefault();
	}
}, true);

function checkOrientAndLocation()
{
	if (window.innerWidth != currentWidth)
	{   
		currentWidth = window.innerWidth;
		var orient = currentWidth == 320 ? "profile" : "landscape";
		document.body.setAttribute("orient", orient);
		setTimeout(scrollTo, 100, 0, 1);
	}

	if (location.hash != currentHash)
	{
		var pageId = location.hash.substr(hashPrefix.length)
		iui.showPageById(pageId);
	}
}

function showDialog(page)
{
	currentDialog = page;
	page.setAttribute("selected", "true");
	
	if (hasClass(page, "dialog") && !page.target)
		showForm(page);
}

function showForm(form)
{
	form.onsubmit = function(event)
	{
		event.preventDefault();
		submitForm(form);
	};
	
	form.onclick = function(event)
	{
		if (event.target == form && hasClass(form, "dialog"))
			cancelDialog(form);
	};
}

function cancelDialog(form)
{
	form.removeAttribute("selected");
}

function updatePage(page, fromPage)
{
	if (!page.id)
		page.id = "__" + (++newPageCount) + "__";

	location.href = currentHash = hashPrefix + page.id;
	pageHistory.push(page.id);

	var pageTitle = $("pageTitle");
	if (page.title) {
		pageTitle.innerHTML = page.title;
	}
	if (page.localName.toLowerCase() == "form" && !page.target)
		showForm(page);
		
	var backButton = $("backButton");
	if (backButton)
	{
		var prevPage = $(pageHistory[pageHistory.length-2]);
		if (prevPage && !page.getAttribute("hideBackButton"))
		{
			backButton.style.display = "inline";
			backButton.innerHTML = prevPage.title ? prevPage.title : "Back";
		}
		else
			backButton.style.display = "none";
	}	
}

function slidePages(fromPage, toPage, backwards)
{		
	var axis = (backwards ? fromPage : toPage).getAttribute("axis");
	if (axis == "y")
		(backwards ? fromPage : toPage).style.top = "100%";
	else
		toPage.style.left = "100%";

	toPage.setAttribute("selected", "true");
	scrollTo(0, 1);
	clearInterval(checkTimer);
	
	var percent = 100;
	slide();
	var timer = setInterval(slide, slideInterval);

	function slide()
	{
		percent -= slideSpeed;
		if (percent <= 0)
		{
			percent = 0;
			if (!hasClass(toPage, "dialog"))
				fromPage.removeAttribute("selected");
			clearInterval(timer);
			checkTimer = setInterval(checkOrientAndLocation, 300);
			setTimeout(updatePage, 0, toPage, fromPage);
		}
	
		if (axis == "y")
		{
			backwards
				? fromPage.style.top = (100-percent) + "%"
				: toPage.style.top = percent + "%";
		}
		else
		{
			fromPage.style.left = (backwards ? (100-percent) : (percent-100)) + "%"; 
			toPage.style.left = (backwards ? -percent : percent) + "%"; 
		}
	}
}

function preloadImages()
{
	var preloader = document.createElement("div");
	preloader.id = "preloader";
	document.body.appendChild(preloader);
}

function submitForm(form)
{
	iui.showPageByHref(form.action || "POST", encodeForm(form), form.method);
}

function encodeForm(form)
{
	function encode(inputs)
	{
		for (var i = 0; i < inputs.length; ++i)
		{
			if (inputs[i].name)
				args.push(inputs[i].name + "=" + escape(inputs[i].value));
		}
	}

	var args = [];
	encode(form.getElementsByTagName("input"));
	encode(form.getElementsByTagName("select"));
	return args;
}

function findParent(node, localName)
{
	while (node && (node.nodeType != 1 || node.localName.toLowerCase() != localName))
		node = node.parentNode;
	return node;
}

function hasClass(self, name)
{
	var re = new RegExp("(^|\\s)"+name+"($|\\s)");
	return re.exec(self.getAttribute("class")) != null;
}

function replaceElementWithSource(replace, source)
{
	var page = replace.parentNode;
	var parent = replace;
	while (page.parentNode != document.body)
	{
		page = page.parentNode;
		parent = parent.parentNode;
	}

	var frag = document.createElement(parent.localName);
	frag.innerHTML = source;

	page.removeChild(parent);

	while (frag.firstChild)
		page.appendChild(frag.firstChild);
}

function $(id) { return document.getElementById(id); }
function ddd() { console.log.apply(console, arguments); }

})();
