/**
 * Nette Framework
 *
 * Copyright (c) 2004, 2008 David Grudl (http://davidgrudl.com)
 *
 * This source file is subject to the "Nette license" that is bundled
 * with this package in the file license.txt.
 *
 * For more information please see http://nettephp.com
 *
 * @version    $Id: nette.js 42 2008-07-24 13:39:55Z David Grudl $
 */

var nette = {

	// public
	lastError: null,

	spinnerId: "spinner",

	processing: 0,

	debug: true,

	result: {},

	action: function(action, sender)
	{
		if (this.processing > 0) return true;

		this.result = {};

		// create new AJAX request
		this.initAjax();
		if (!this.ajax) return false;

		action += (action.indexOf('?') == -1) ? '?' : '&';
		if (typeof(this.state) === 'object') {
			action += this.buildQuery(this.state, '', '');
		}

		// create process indicator
		try {
			var img = document.getElementById(this.spinnerId);
			if (sender && img) {
				this.spinner = img.cloneNode(true);
				this.spinner.style.display = 'inline';
				sender.parentNode.insertBefore(this.spinner, sender.nextSibling);
			}
		} catch (e) {
		}

		try {
			var url = action + '-r=' + Math.random();
			var query = null;

			this.ajax.open("POST", url, true);
			this.ajax.setRequestHeader("X-Requested-With", "XMLHttpRequest");
			//this.ajax.setRequestHeader("Content-Type","application/x-www-form-urlencoded");
			this.ajax.onreadystatechange = function() { nette.ajaxHandler(); }
			this.ajax.send(query);
			this.processing = 1;
			return true;

		} catch (e) {
			return false;
		}
	},



	onSuccess: function()
	{
		if (this.result.error) {
			this.onError(this.result.error.message);
			return;
		}

		if (this.result.redirect) {
			var url = this.result.redirect;
			if (this.debug) {
				alert(url);
			}
			document.location = url;
			return;
		}

		if (this.result.state) {
			this.state = this.result.state;
		}

		if (this.result.events) {
			for (var id in this.result.events) {
				this.handleEvent(this.result.events[id].event, this.result.events[id].args);
			}
		}
		if (this.result.snippets) {
			for (var id in this.result.snippets) {
				this.updateSnippet(id, this.result.snippets[id]);
			}
		}

		this.result = {};
	},


	onError: function(message)
	{
		this.lastError = message;

		if (this.debug) {
			alert(message);
		}
	},


	updateSnippet: function(id, html)
	{
		var el = document.getElementById(id);
		if (el) el.innerHTML = html;
	},

	handleEvent: function(event, args)
	{
		if (this.debug) {
			//alert(event + '(' + args + ')');
		}
		var obj = event.split('.');
		obj.pop();
		obj = obj.join('.');
		eval(event + '.apply(' + obj + ', args);');
	},


	// private
	state: null,

	spinner: null,

	ajax: null,


	initAjax: function()
	{
		this.ajax = false;

		if (typeof XMLHttpRequest !== 'undefined') {
			this.ajax = new XMLHttpRequest();
		}

		if (!this.ajax && window.ActiveXObject) {
			try {
				this.ajax = new ActiveXObject("Msxml2.XMLHTTP");
			} catch (e) {
				try {
					this.ajax = new ActiveXObject("Microsoft.XMLHTTP");
				} catch (e) {
					this.ajax = false;
				}
			}
		}
	},


	ajaxHandler: function()
	{
		if (this.ajax.readyState == 4) {
			// remove process indicator
			if (this.spinner) {
				this.spinner.parentNode.removeChild(this.spinner);
				this.spinner = null;
			}

			if (this.ajax.status === 200) {
				//alert(this.ajax.responseText);
				eval('this.result = ' + this.ajax.responseText);
				this.onSuccess();

			} else  {
				this.onError(this.ajax.status + " " + this.ajax.statusText + "\n\n" + this.ajax.responseText);
			}

			this.processing -= 1;
			this.ajax = false;
		}
	},


	buildQuery: function(data, prefix, postfix)
	{
		var s = '';
		for (var key in data) {
			if (typeof(data[key]) === 'object') {
				s += this.buildQuery(data[key], prefix + encodeURIComponent(key) + postfix + '%5B', '%5D');
			} else {
				if (data[key] === true || data[key] === false) {
					data[key] = data[key] ? '1' : '0';
				}
				s += prefix + encodeURIComponent(key) + postfix + '=' + encodeURIComponent((data[key].toString())) + '&';
			}
		}
		return s.replace(/%20/g, '+');
	}
}