window.addEventListener ('load',
	function () { Vn.Web.initialize (); });

Vn.Web = 
{
	 modules: {}
	,activeForm: null
	,requestedForm: null

	,initialize: function ()
	{
		this.loadingCount = 0;
		this.loader = Vn.get ('loader');

		this.formHolder = Vn.get ('module');

		this.hash = new Vn.Hash ();
		this.hashLink = new Vn.HashLink
		({
			 hash: this.hash
			,key: 'module'
		});
		this.hashLink.on ('changed', this.onHashChange, this);

		this.conn = new Db.Conn ();
		this.conn.on ('error', this.onConnError, this);
		this.conn.on ('loading-changed', this.onConnLoading, this);
		this.conn.open (null, null, null, this.connOpened.bind (this));
	}
	
	,connOpened: function (conn, success)
	{
		var sql = 'SELECT default_module, image_dir FROM config';
		this.conn.execQuery (sql, this.queryConfigDone.bind (this));
	
		var sql = 'SELECT name FROM customer_view';
		this.conn.execQuery (sql, this.queryUserDone.bind (this));
	
		var sql = 'CALL module_list ()';
		this.conn.execQuery (sql, this.onModuleListLoad.bind (this));
	}

	,queryConfigDone: function (resultSet)
	{
		var res = resultSet.fetchResult ();
		var columns = res.columns;
	
		if (res.next ())
		for (var i = 0; i < res.columns.length; i++)
			Vn.Config[columns[i].name] = res.get (columns[i].name);

		this.onHashChange ();
	}
	
	,queryUserDone: function (resultSet)
	{
		var userName = resultSet.fetchValue ();
	
		if (userName)
		{
			var span = Vn.get ('user-name');
			span.appendChild (document.createTextNode (', '+ userName));
		}
	}

	,onConnError: function (conn, error)
	{
		switch (error.domain)
		{
			case 'Auth':
				this.unload ();
				location.assign ('?page=login#!error='+ error.code);
				break;
			case 'Version':
				this.newVersion (error);
				break;
			case 'Conn':
				alert (error.message);
				break;
			default:
				console.warn (error.message);
		}
	}
	
	,newVersion: function (error)
	{
		if (this.skipVersion)
			return;

		this.skipVersion = true;

		var reload;
		var message = _('NewVersionAvailable') +"\n\n"+ error.message;

		if (error.code == 'criticalVersion')
		{
			alert (message)
			reload = true;
		}
		else
			reload = confirm (message);
		
		if (reload)
		{
			this.unload ();
			location.reload ();
		}
	}
	
	,onHashChange: function ()
	{
		var x = this.hashLink.value;
		this.openModule (x ? x : Vn.Config['default_module']);
	}

	,onModuleListLoad: function (resultSet)
	{
		var res = resultSet.fetchResult ();	
		var sectionMap = {};
		
		if (res)
		for (var i = 0; res.next (); i++)
		{
			var parent = res.get ('parent');
			
			if (!sectionMap[parent])
				sectionMap[parent] = [];
				
			sectionMap[parent].push (i);
		}

		this.createMenu (res, sectionMap, null, Vn.get ('menu'));
	}

	,createMenu: function (res, sectionMap, parent, ul)
	{
		var sections = sectionMap[parent];

		for (var i = 0; i < sections.length; i++)
		{
			res.row = sections[i];
		
			var li = document.createElement ('li');
			ul.appendChild (li);

			var a = document.createElement ('a');
			a.href = this.hash.make ({'module': res.get ('file')});
			li.appendChild (a);

			var text = document.createTextNode (_(res.get ('description')));
			a.appendChild (text);
			
			var moduleId = res.get ('id');
			
			if (sectionMap[moduleId])
			{
				var submenu = document.createElement ('ul');
				submenu.className = 'submenu';
				li.appendChild (submenu);

				li.addEventListener ('mouseover',
					this.onLiMouseHover.bind (this, submenu, a));
				li.addEventListener ('mouseout',
					this.onLiMouseOut.bind (this));
	
				this.createMenu (res, sectionMap, moduleId, submenu);
			}
		}
	}

	,onLiMouseHover: function (submenu, parent)
	{
		this.hideSubmenu ();
		this.activeSubmenu = submenu;

		var rect = parent.getBoundingClientRect ();
		submenu.style.display = 'inline';
		submenu.style.left = rect.left +'px';
		submenu.style.top = rect.bottom +'px';
	}
	
	,onLiMouseOut: function ()
	{
		this.timeout = setTimeout (this.hideSubmenu.bind (this), 160);
	}
	
	,hideSubmenu: function ()
	{
		var submenu = this.activeSubmenu;
	
		if (submenu)
		{
			submenu.style.display = 'none';
			clearTimeout (this.timeout);
			this.activeSubmenu = null;
			this.timeout = 0;
		}
	}

	,onConnLoading: function (conn, isLoading)
	{
		if (isLoading)
			this.loaderPush ();
		else
			this.loaderPop ();
	}
	
	,loaderPush: function ()
	{
		this.loadingCount++;

		if (this.loadingCount == 1)
			this.loader.style.visibility = 'visible';
	}
	
	,loaderPop: function ()
	{
		this.loadingCount--;
		
		if (this.loadingCount == 0)
			this.loader.style.visibility = 'hidden';
	}

	,openModule: function (name)
	{
		this.requestedForm = name;
		this.loadModule (name, this.onModuleLoad.bind (this));
	}
	
	,onModuleLoad: function (module)
	{
		if (module.name != this.requestedForm)
			return;
			
		if (this.activeForm)
			this.activeForm.close ();

		var klassName = 'Vn.'
			+ module.name.charAt (0).toUpperCase ()
			+ module.name.substr (1);

		try {
			var klass = eval (klassName);
			this.activeForm = new klass (this, module);
			this.activeForm.activate ();
		}
		catch (e) {
			console.error (e);
		}
	}
	
	,loadModule: function (name, callback)
	{
		var x = this.modules[name];

		if (!x)
		{
			x = {
				 name: name
				,status: 3
				,xml: null
				,callbacks: []
			};
			
			if (callback)
				x.callbacks.push (callback);

			var path = 'modules/'+ name;

			Vn.Locale.load (path,
				this.onPartDownload.bind (this, x));
			Vn.includeJs (path +'/'+ name +'.js',
				this.onPartDownload.bind (this, x));
			Vn.includeCss (path +'/style.css');

			var request = new XMLHttpRequest ();
			request.onreadystatechange =
				this.onXmlDownload.bind (this, x, request);
			request.open ('get', 'module.php?module='+ name, true);
			request.send ();

			this.modules[name] = x;
			this.loaderPush ();
		}
		else if (callback)
		{
			if (x.status == 0)
				callback (x);
			else
				x.callbacks.push (callback);
		}
	}
	
	,onXmlDownload: function (module, request)
	{
		if (request.readyState != 4)
			return;
		if (request.status == 200)
			module.xml = request;

		this.onPartDownload (module);
	}
	
	,onPartDownload: function (m)
	{
		m.status--;

		if (m.status != 0)
			return;

		var x = m.callbacks;
		delete m.callbacks;

		for (var i = 0; i < x.length; i++)	
			x[i] (m);

		this.loaderPop ();
	}
	
	,unload: function ()
	{
		this.hashLink.disconnect ('changed', this.onHashChange, this);
		this.conn.disconnect ('error', this.onConnError, this);
		this.conn.disconnect ('loading-changed', this.onConnLoading, this);
	}
};