function App() {
	this.login = new Login(this);
	this.currentIndex = -1;

	var color = localStorage.color;
	if(!color) color = "red";
	this.setColor(color);
	this.fontChange();

	var numArticles = localStorage.numArticles;
	if(!numArticles) numArticles = 50;
	this.numArticles(numArticles);
	var maxDownload = localStorage.maxDownload;
	if(!maxDownload) maxDownload = 500000;
	this.maxDownload(maxDownload);
};

App.prototype.authenticate = function() {
	
};

App.prototype.after_login = function(backend) {

	var request = window.navigator.mozApps.getSelf();
	request.onsuccess = function() {
		$("#version").innerHTML = request.result.manifest.version;
	}

	var _this = this;

	window.onhashchange = function(e) {

		// do not reload page
		e.preventDefault();
 		e.stopPropagation();

		var url = window.location.hash;

		if(url == "#list") {
			_this.setCurrentRead();
			_this.changeToPage("#list");
		} if(url.indexOf("#list-") == 0) {
			var feedId = parseInt(url.replace("#list-", ""), 10);
			_this.reload(feedId);
			_this.changeToPage("#list");
		} else if(url == "#reload") {
			_this.reload();
		} else if(url == "#settings") {
			_this.changeToPage("#settings");
		} else if(url == "#categories" || url == "#categories-back") {
			_this.changeToPage("#categories");
			var isComingBack = (url == "#categories-back") ? true : false;
			_this.loadCategories(isComingBack);
		} else if (url.indexOf("#categories-") == 0) {
			var categoryId = parseInt(url.replace("#categories-", ""), 10);
			_this.loadCategoryFeeds(categoryId);
		} else if(url.indexOf("#color-") == 0) {
			var color = url.replace("#color-", "");
			_this.setColor(color);
		} else if(url.indexOf("#full-") == 0) {
			var i = parseInt(url.replace("#full-", ""), 10);
			_this.showFull(_this.unread_articles[i]);
		} else if(url == "#unread") {
			_this.toggleCurrentUnread();
		} else if(url == "#starred") {
			_this.toggleStarred();
		} else if(url == "#published") {
			_this.togglePublished();
		} else if(url == "#logout") {
			_this.logout();
		} else if(url == "#reset-info") {
			alert("Info bubbles will be shown again.")
			$$(".info").forEach(function(o) {
				o.removeClass("hidden");
			});
		} else if(url == "#next") {
			_this.showNext();
		} else if(url == "#previous") {
			_this.showPrevious();
		} else if(url == "#font-smaller") {
			_this.fontChange("smaller");
		} else if(url == "#font-bigger") {
			_this.fontChange("bigger");
		} else if(url == "#all-read") {
			_this.toggleAllRead();
		}

		// this is here so you can tap on a button more then once
		// and it will still call onhashchange
		window.location.hash = "#";
	}

	// FIXME move that code somewhere else
	$(".info.swipe").ontouchend = function(e) {
		localStorage.info_swipe = true;
		$(".info.swipe").addClass("hidden");
	};

	var supportsTouch = 'ontouchend' in document;

	if(!supportsTouch || localStorage.info_swipe) {
		$(".info.swipe").addClass("hidden");
	}

	// set up swiping
	var options = {
		dragLockToAxis: true,
		dragBlockHorizontal: true
	};
	var hammertime = new Hammer($("#full"), options);
	hammertime.on("dragleft", function(ev){ ev.gesture.preventDefault(); });
	hammertime.on("dragright", function(ev){ ev.gesture.preventDefault(); });
	hammertime.on("swipeleft", function(ev){ _this.showNext(); ev.gesture.preventDefault(); });
	hammertime.on("swiperight", function(ev){ _this.showPrevious(); ev.gesture.preventDefault(); });

	if(backend == "OwnCloud") {
		this.backend = new OwnCloud(this, localStorage.server_url, localStorage.session_id);
	} else if (backend == "Pond") {
		this.backend = new Pond(this, localStorage.server_url, localStorage.session_id)
	} else {
		this.backend = new TinyTinyRSS(this, localStorage.server_url, localStorage.session_id);
		$("#setpublished").removeClass("invisible");
	}

	this.changeToPage("#categories");
	this.loadCategories();

	var numArticles = localStorage.numArticles;
	if(!numArticles) numArticles = 50;
	this.numArticles(numArticles);
	var maxDownload = localStorage.maxDownload;
	if(!maxDownload) maxDownload = 500000;
	this.maxDownload(maxDownload);

	this.reload();
};

App.prototype.logout = function() {
	this.backend.logOut();
	this.unread_articles = [];
	this.populateList();
	this.login.log_out();
};

App.prototype.changeToPage = function(page) {

	// FIXME
	var active = $(".active");
	if(active.id == "list") {
		this.saveScrollTop = document.body.scrollTop;
	}

	if(page == "#list") {
		document.body.scrollTop = this.saveScrollTop;
	} else {
		window.scroll(0, 0);
	}

	active.removeClass("active");
	$(page).addClass("active");
};

App.prototype.setColor = function(color) {
	localStorage.color = color;
	document.body.className = "";
	document.body.addClass(color);
	this.updatePieChart();
};

App.prototype.reload = function(feedId) {
	this.unread_articles = [];
	$("#all-read").addClass('inactive');
	var number=parseInt(localStorage.numArticles);
	this.backend.reload(this.gotUnreadFeeds.bind(this),number, feedId);
};

App.prototype.loadCategories = function (isComingBack) {
	if (this.categories && isComingBack != true) {
		populateCategoryList();
	} else {
		this.backend.getCategories(this.gotCategories.bind(this));
	}
}

App.prototype.loadCategoryFeeds = function (categoryId) {
	this.backend.getFeedsByCategory(categoryId, this.gotCategoryFeeds.bind(this));
}

App.prototype.gotUnreadFeeds = function(new_articles) {

	if(new_articles == null || !this.validate(new_articles)) {
            
                // Check if we did not get a NOT_LOGGED_IN error, and ask the
                // user to login again if it is the case.
                // This can happen with TT-RSS backend
                if (new_articles.error && new_articles.error === "NOT_LOGGED_IN") {
                    alert("Your TinyTinyRSS session has expired. Please login again");
                    this.login.fillLoginFormFromLocalStorage();
                    this.login.log_in();
                }
                else {
                    // On other errors, load the saved unread articles.
                    var old_articles = localStorage.unread_articles;
                    if(old_articles) {
                            this.unread_articles = JSON.parse(old_articles);	
                    }
                    this.populateList();
                    this.isShowingFeeds = true;
                }
                
	} else {
            
                this.unread_articles = this.unread_articles.concat(new_articles);

                if(new_articles.length > 0) {
                    this.populateList();
                    this.isShowingFeeds = true;
                }
	}
};

App.prototype.gotCategories = function (categories) {
	if (!categories) {
		//FIXME this is repeated code, so create a function for it
		// Check if we did not get a NOT_LOGGED_IN error, and ask the
        // user to login again if it is the case.
        // This can happen with TT-RSS backend
        if (new_articles.error && new_articles.error === "NOT_LOGGED_IN") {
            alert("Your TinyTinyRSS session has expired. Please login again");
            this.login.fillLoginFormFromLocalStorage();
            this.login.log_in();
        }
	} else {
		this.categories = categories;
        if(categories.length > 0) {
            try {
                //To check if when it fails it is the same
                localStorage.categories = JSON.stringify(this.categories);
            }
            catch (e) {
                alert("Reached maximum memory by app " + e.name + " " + e.message + ". We will keep working in anycase with: " + localStorage.categories.length);
            }
			this.populateCategoryList();
        }
	}
};

App.prototype.gotCategoryFeeds = function (feeds) {
	this.feeds = feeds;
	this.populateFeedList();
};

App.prototype.validate = function(articles) {

	if(articles.length == 0) return true;

	for (var i = 0; i < articles.length; i++) {
		if(typeof articles[i].title != "undefined") return true;
	}

	return false;
};

App.prototype.populateList = function() {

	var html_str = "";
	for (var i = 0; i < this.unread_articles.length; i++) {
		var article = this.unread_articles[i];
		html_str += "<li"+ (article.unread ? " class='unread'" : "") +">";
		html_str += "<a href='#full-"+i+"'>";
		html_str += "<p class='title'>" + article.feed_title + "</p>";
		html_str += "<h2>" + article.title + "</h2>";
		if(article.excerpt)	html_str += "<p class='excerpt'>" + article.excerpt + "</p>";
		html_str += "</a></li>";
	}
	
	$("#list ul").innerHTML = html_str;

	this.updatePieChart();
};

App.prototype.updateList = function() {
	var unread = 0;
	$$("#list ul li").forEach(function(o, i) {

		if(!this.unread_articles[i].unread) {
			o.removeClass("unread");
		}
		else {
			unread++;
			o.addClass("unread");
		}
	}, this);

	if(unread > 0) {
		$("#all-read").addClass('inactive');
	} else {
		$("#all-read").removeClass('inactive');
	}

	this.updatePieChart();
};

App.prototype.populateCategoryList = function () {
	var html_str = "";
	for (var i = 0; i < this.categories.length; i++) {
		var category = this.categories[i];
		html_str += "<li>";
		html_str += "<a href='#categories-"+category.id+"'>";
		html_str += "<p class='title'>" + category.title + "</p>";
		html_str += "</a>";
		html_str += "</li>";
	}
	
	$("#categories ul").innerHTML = html_str;
};

App.prototype.populateFeedList = function () {
	var html_str = "";
	for (var i = 0; i < this.feeds.length; i++) {
		var feed = this.feeds[i];
		html_str += "<li>";
		html_str += "<a href='#list-"+feed.id+"'>";
		html_str += "<p class='title'>" + feed.title + "</p>";
		html_str += "</a>";
		html_str += "</li>";
	}
	
	$("#categories ul").innerHTML = html_str;
};

App.prototype.updatePieChart = function() {

	if(!this.unread_articles) return; // happens on loginpage

	var all = this.unread_articles.length;
	var unread = 0;
	for (var i = 0; i < all; i++) {
		if(this.unread_articles[i].unread) unread++;
	};


	var a = 100 / all * unread;
	var b = 100 / all * (all - unread);

	var bg = window.getComputedStyle($("body"), null).backgroundColor;
	var fg = window.getComputedStyle($(".bar"), null).backgroundColor;
	var tx = window.getComputedStyle($(".bar"), null).color;

	var myColor = [bg, fg];

	var data = [a, b];

	$$("canvas").forEach(function(canvas) {
		var ctx = canvas.getContext("2d");
		var lastend = 0;
		var myTotal = 0;

		for(var e = 0; e < data.length; e++) myTotal += data[e];

		for (var i = 0; i < data.length; i++) {
			ctx.fillStyle = myColor[i];
			ctx.beginPath();
			ctx.moveTo(canvas.width/2, canvas.height/2);
			ctx.arc(canvas.width/2, canvas.height/2, canvas.height/2, lastend, lastend+(Math.PI*2*(data[i]/myTotal)), false);
			ctx.lineTo(canvas.width/2, canvas.height/2);
			ctx.fill();
			lastend += Math.PI*2*(data[i]/myTotal);
		}

		if(all > 0) {
			ctx.font =  "12px FeuraSans, sans-serif";
			ctx.fillStyle = tx;
			ctx.textAlign = "center";
			var text = unread + "/" + all;
			var x = canvas.width / 2;
			var y = canvas.height / 2 + 4;
			ctx.fillText(text, x, y, canvas.width-6);			
		}
	})
};

App.prototype.showFull = function(article, slide_back) {

	this.changeToPage("#full");

	this.currentIndex = this.unread_articles.indexOf(article);

	var page_id = "#full";

	$(page_id + " .date").innerHTML = (new Date(parseInt(article.updated, 10) * 1000)).toLocaleString();

	var title = $(page_id + " .title");
	title.innerHTML = article.title;
	title.href = article.link;

	$(page_id + " .feed_title").innerHTML = article.feed_title;

	$(page_id + " .author").innerHTML = "";
	if(article.author && article.author.length > 0)
		$(page_id + " .author").innerHTML = "&ndash; " + article.author; 

	$(page_id + " .article").innerHTML = article.content;

	// Open all links in browser
	$$(page_id + " .article a").forEach(function(o, i) {
		o.target = "_blank";
	});

	if(article.unread) {
		$("#setunread").addClass('inactive');
	} else {
		$("#setunread").removeClass('inactive');
	}

	if(!article.marked) {
		$("#setstarred").addClass('inactive');
	} else {
		$("#setstarred").removeClass('inactive');
	}

	if(!article.published) {
		$("#setpublished").addClass('inactive');
	} else {
		$("#setpublished").removeClass('inactive');
	}

};

App.prototype.showNext = function() {
	this.setCurrentRead();

	if(this.currentIndex >= this.unread_articles.length - 1) {
		this.goToList();
	} else {
		this.currentIndex++;
		this.showFull(this.unread_articles[this.currentIndex], false);
	}
};

App.prototype.showPrevious = function() {
	this.setCurrentRead();

	if(this.currentIndex <= 0) {
		this.goToList();
	} else {
		this.currentIndex--;
		this.showFull(this.unread_articles[this.currentIndex], true);
	}
};

App.prototype.setCurrentRead = function() {
	var article = this.unread_articles[this.currentIndex];
	if(!article) return; // happens if we're not on a full article site
	if(!article.set_unread) {
		article.unread = false;
		this.updateList();
		this.backend.setArticleRead(article);
	}

	article.set_unread = false;

	$("#setunread").removeClass('inactive');

	this.updatePieChart();
};

App.prototype.toggleCurrentUnread = function() {
	var article = this.unread_articles[this.currentIndex];
	if(article.unread) {
		article.unread = false;
		article.set_unread = false;
		$("#setunread").removeClass('inactive');
	} else {
		article.unread = true;
		article.set_unread = true;
		$("#setunread").addClass('inactive');
	}

	this.updateList();
	this.backend.setArticleUnread(article);
};

App.prototype.toggleAllRead = function() {

	if($("#all-read").hasClass('inactive')) { // set all read

		var articles = [];
		for (var i = 0; i < this.unread_articles.length; i++) {
			var article = this.unread_articles[i];
			article.unread = false;
			article.set_unread = false;
			articles.push(article);
		}
		$("#all-read").removeClass('inactive');

		this.updateList();

		this.backend.setArticlesRead(articles);

	} else {

		var articles = [];
		for (var i = 0; i < this.unread_articles.length; i++) {
			var article = this.unread_articles[i];
			article.unread = true;
			article.set_unread = false;
			articles.push(article);
		}
		$("#all-read").addClass('inactive');
		this.updateList();

		this.backend.setArticlesUnread(articles);

	}
};

App.prototype.toggleStarred = function() {
	var article = this.unread_articles[this.currentIndex];
	if(!article) return; // happens if we're not on a full article site
	
	if(!article.marked) {
		article.marked = true;
		this.updateList();
		this.backend.setArticleStarred(article);
		$("#setstarred").removeClass('inactive');
	}
	else {
		article.marked = false;
		this.updateList();
		this.backend.setArticleUnstarred(article);
		$("#setstarred").addClass('inactive');
	}

};

App.prototype.togglePublished = function() {
	var article = this.unread_articles[this.currentIndex];
	if(!article) return; // happens if we're not on a full article site
	
	if(!article.published) {
		article.published = true;
		this.backend.setArticlePublished(article);
		$("#setpublished").removeClass('inactive');
	}
	else {
		article.published = false;
		this.backend.setArticleUnpublished(article);
		$("#setpublished").addClass('inactive');
	}

};

App.prototype.goToList = function() {
	this.changeToPage("#list");
};

App.prototype.fontChange = function(size) {
	if(size == "bigger") {
		
		var i = localStorage.font_size;
		if(i < 5) {
			document.body.removeClass("f" + i);
			i++;
			document.body.addClass("f" + i);
			localStorage.font_size = i;
		}

	} else if(size == "smaller") {

		var i = localStorage.font_size;
		if(i > 1) {
			document.body.removeClass("f" + i);
			i--;
			document.body.addClass("f" + i);
			localStorage.font_size = i;
		}

	} else {

		var i = localStorage.font_size;
		if(typeof i == "undefined") {
			i = localStorage.font_size = 2;
		}

		document.body.addClass("f" + i);
	}

};

App.prototype.numArticles= function(askfor) {
	if(askfor < 200 && askfor > 0) {
		localStorage.numArticles=askfor;
	}
	else {
		localStorage.numArticles=100;
	}
};

App.prototype.maxDownload= function(maxdata) {
	if(maxdata < 5000000 && maxdata > 100000) {
		localStorage.maxDownload=maxdata;
	}
	else {
		localStorage.maxDownload=500000;
	}
};