/**
 * eGroupWare API: JSON - Contains the client side javascript implementation of class.egw_json.inc.php
 *
 * @link http://www.egroupware.org
 * @license http://opensource.org/licenses/gpl-license.php GPL - GNU General Public License
 * @package api
 * @subpackage ajax
 * @author Andreas Stoeckel <as@stylite.de>
 * @version $Id$
 */

/* The egw_json_request is the javaScript side implementation of class.egw_json.inc.php.*/

function _egw_json_escape_string(input)
{
	var len = input.length;
	var res = "";

	for (var i = 0; i < len; i++)
	{
		switch (input.charAt(i))
		{
			case '"':
				res += '\\"';
				break;

			case '\n':
				res += '\\n';
				break;

			case '\r':
				res += '\\r';
				break;

			case '\\':
				res += '\\\\';
				break;

			case '\/':
				res += '\\/';
				break;

			case '\b':
				res += '\\b';
				break;

			case '\f':
				res += '\\f';
				break;

			case '\t':
				res += '\\t';
				break;

			default:
				res += input.charAt(i);
		}
	}

	return res;
}

function _egw_json_encode_simple(input)
{
	switch (input.constructor)
	{
		case String:
			return '"' + _egw_json_escape_string(input) + '"';

		case Number:
			return input.toString();

		case Boolean:
			return input ? 'true' : 'false';

		default:
			return null;
	}
}

function egw_json_encode(input)
{
	if (input == null || !input && input.length == 0) return 'null';

	var simple_res = _egw_json_encode_simple(input);
	if (simple_res == null)
	{
		switch (input.constructor)
		{
			case Array:		
				var buf = [];
				for (var k in input)
				{
					//Filter the remove function, which is added to arrays in egw_fw_classes
					if (k != 'remove')
						buf.push(egw_json_encode(input[k]));
				}
				return '[' + buf.join(',') + ']';

			case Object:
				var buf = [];
				for (var k in input)
				{
					buf.push(_egw_json_encode_simple(k) + ':' + egw_json_encode(input[k]));
				}
				return '{' + buf.join(',') + '}';

			default:
				return 'null';
		}
	}
	else
	{
		return simple_res;
	}
}


/**
 * Some variables needed to store which JS and CSS files have already be included
 */
var egw_json_files = {};

/**
 * Variable which stores all currently registered plugins
 */
var _egw_json_plugins = [];

/**
 * Register a plugin for the egw_json handler
 */
function egw_json_register_plugin(_callback, _context)
{
	//Default the context parameter to "window"
	if (typeof _context == 'undefined') {
		_context = window;
	}

	//Add a plugin object to the plugins array
	_egw_json_plugins[_egw_json_plugins.length] = {
		'callback': _callback,
		'context': _context
	};
}

/**
 * Function used internally to pass a response to all registered plugins
 */
function _egw_json_plugin_handle(_type, _response) {
	for (var i = 0; i < _egw_json_plugins.length; i++)
	{
		try {
			var plugin = _egw_json_plugins[i];
			if (plugin.callback.call(plugin.context, _type, _response)) {
				return true;
			}
		} catch (e) {
			if (typeof console != 'undefined')
			{
				console.log(e);
			}
		}
	}

	return false;
}

/** The constructor of the egw_json_request class.
 *
 * @param string _menuaction the menuaction function which should be called and
 *   which handles the actual request. If the menuaction is a full featured
 *   url, this one will be used instead.
 * @param array _parameters which should be passed to the menuaction function.
 * @param object _context is the context which will be used for the callback function 
 */
function egw_json_request(_menuaction, _parameters, _context)
{
	this.context = window.document;
	if (typeof _context != 'undefined')
		this.context = _context;

	if (typeof _parameters != 'undefined')
	{
		this.parameters = _parameters;
	}
	else
	{
		this.parameters = new Array;
	}

	// Check whether the supplied menuaction parameter is a full featured url
	// or just a menuaction
	if (_menuaction.match(/json.php\?menuaction=[a-z_0-9]*\.[a-z_0-9]*\.[a-z_0-9]*/i))
	{
		// Menuaction is a full featured url
		this.url = _menuaction
	}
	else
	{
		// We only got a menu action, assemble the url manually.
		this.url = this._assembleAjaxUrl(_menuaction);
	}

	this.request = null;
	this.sender = null;
	this.callback = null;
	this.alertHandler = this.alertFunc;
	this.onLoadFinish = null;
	this.loadedJSFiles = {};
	this.handleResponseDone = false;
	if (window.egw_alertHandler)
	{
		this.alertHandler = window.egw_alertHandler;
	}
}

egw_json_request.prototype._assembleAjaxUrl = function(_menuaction)
{
	// Retrieve the webserver url
	var webserver_url = egw_topWindow().egw_webserverUrl;

	// Check whether the webserver_url is really set
	// Don't check for !webserver_url as it might be empty.
	// Thank you to Ingo Ratsdorf for reporting this.
	if (typeof webserver_url == "undefined")
	{
		throw "Internal JS error, top window not found, webserver url could not be retrieved.";
	}

	// Add the ajax relevant parts
	return webserver_url + '/json.php?menuaction=' + _menuaction;
}

/**
 * Sends the AJAX JSON request.
 *
 * @param boolean _async specifies whether the request should be handeled asynchronously (true, the sendRequest function immediately returns to the caller) or asynchronously (false, the sendRequest function waits until the request is received)
 * @param _callback is an additional callback function which should be called upon a "data" response is received
 * @param _sender is the reference object the callback function should get
*/
egw_json_request.prototype.sendRequest = function(_async, _callback, _sender)
{
	//Store the sender and callback parameter inside this class	
	this.sender = _sender;
	if (typeof _callback != "undefined")
		this.callback = _callback;

	//Copy the async parameter which defaults to "true"	
	var is_async = true;
	if (typeof _async != "undefined")
		is_async = _async;

	//Assemble the actual request object containing the json data string
	var request_obj = {
		"json_data": egw_json_encode(
		{
			"request": {
				"parameters": this.parameters
			}
		})
	};

	//Send the request via the jquery AJAX interface to the server
	this.request = $.ajax({url: this.url,
		async: is_async,
		context: this,
		data: request_obj,
		dataType: 'json',
		type: 'POST', 
		success: this.handleResponse,
		error: function(_xmlhttp,_err) { alert('Ajax request to ' + this.url + ' failed: ' + _err); }
	});
}

egw_json_request.prototype.abort = function()
{
	this.request.abort();
}

egw_json_request.prototype.alertFunc = function(_message, _details)
{
	alert(_message);
	if(_details) _egw_json_debug_log(_message, _details);
}

function _egw_json_debug_log(_msg, _e)
{
	if (typeof console != "undefined" && typeof console.log != "undefined")
	{
		console.log(_msg, _e);
	}
}

/* Displays an json error message */
egw_json_request.prototype.jsonError = function(_msg, _e)
{
	var msg = 'EGW JSON Error: '._msg;

	//Log and show the error message
	_egw_json_debug_log(msg, _e);
	this.alertHandler(msg);
}

/* Internal function which handles the response from the server */
egw_json_request.prototype.handleResponse = function(data, textStatus, XMLHttpRequest)
{
	this.handleResponseDone = false;
	if (data && data.response)
	{
		var hasResponse = false;
		for (var i = 0; i < data.response.length; i++)
		{
			try
			{
				var res = data.response[i];				

				switch (data.response[i].type)
				{
					case 'alert':
						//Check whether all needed parameters have been passed and call the alertHandler function
						if ((typeof res.data.message != 'undefined') && 
							(typeof res.data.details != 'undefined'))
						{					
							this.alertHandler(
								res.data.message,
								res.data.details)
							hasResponse = true;
						} else
							throw 'Invalid parameters';
						break;
					case 'assign':
						//Check whether all needed parameters have been passed and call the alertHandler function
						if ((typeof res.data.id != 'undefined') && 
							(typeof res.data.key != 'undefined') &&
							(typeof res.data.value != 'undefined'))
						{					
							var obj = document.getElementById(res.data.id);
							if (obj)
							{
								obj[res.data.key] = res.data.value;
								hasResponse = true;
							}
						} else
							throw 'Invalid parameters';
						break;
					case 'data':
						//Callback the caller in order to allow him to handle the data
						if (this.callback)
						{
							this.callback.call(this.sender, res.data);
							hasResponse = true;
						}
						break;
					case 'script':
						if (typeof res.data == 'string')
						{
							try
							{
								var func = function() {eval(res.data);};
								func.call(window);
							}
							catch (e)
							{
								e.code = res.data;
								_egw_json_debug_log(e);
							}
							hasResponse = true;
						} else
							throw 'Invalid parameters';
						break;
					case 'jquery':
						if (typeof res.data.select == 'string' &&
							typeof res.data.func == 'string')
						{
							try
							{
								var jQueryObject = $(res.data.select, this.context);
								jQueryObject[res.data.func].apply(jQueryObject,	res.data.parms);
							}
							catch (e)
							{
								_egw_json_debug_log(e, {'Function': res.data.func, 'Parameters': res.data.params});
							}
							hasResponse = true;
						} else
							throw 'Invalid parameters';
						break;
					case 'redirect':
						if (typeof res.data.url == 'string' &&
							typeof res.data.global == 'boolean')
						{
							//Special handling for framework reload
							res.data.global |= (res.data.url.indexOf("?cd=10") > 0);

							if (res.data.global)
							{
								egw_topWindow().location.href = res.data.url;
							}
							else
							{
								window.location.href = res.data.url;
							}

							hasResponse = true;
						} else
							throw 'Invalid parameters';
						break;
					case 'css':
						if (typeof res.data == 'string')
						{
							//Check whether the requested file had already be included
							if (!egw_json_files[res.data])
							{
								egw_json_files[res.data] = true;

								//Get the head node and append a new link node with the stylesheet url to it
								var headID = document.getElementsByTagName('head')[0];
								var cssnode = document.createElement('link');
								cssnode.type = "text/css";
								cssnode.rel = "stylesheet";
								cssnode.href = res.data;
								headID.appendChild(cssnode);
							}
							hasResponse = true;
						} else
							throw 'Invalid parameters';
						break;
					case 'js':
						if (typeof res.data == 'string')
						{
							//Check whether the requested file had already be included
							if (!egw_json_files[res.data])
							{
								egw_json_files[res.data] = true;

								//Get the head node and append a new script node with the js file to it
								var headID = document.getElementsByTagName('head')[0];
								var scriptnode = document.createElement('script');
								scriptnode.type = "text/javascript";
								scriptnode.src = res.data;
								scriptnode._originalSrc = res.data;
								headID.appendChild(scriptnode);

								//Increment the includedJSFiles count
								this.loadedJSFiles[res.data] = false;

								if (typeof console != 'undefined' && typeof console.log != 'undefined')
									console.log("Requested JS file '%s' from server", [res.data]);

								var self = this;

								//FF, Opera, Chrome
								scriptnode.onload = function(e) {
									var file = e.target._originalSrc;
									if (typeof console != 'undefined' && typeof console.log != 'undefined')
										console.log("Retrieved JS file '%s' from server", [file]);

									self.loadedJSFiles[file] = true;
									self.checkLoadFinish();
								};

								//IE
								if (typeof scriptnode.readyState != 'undefined')
								{
									if (scriptnode.readyState != 'complete' &&
									    scriptnode.readyState != 'loaded')
									{
										scriptnode.onreadystatechange = function() {
											var node = window.event.srcElement;
											if (node.readyState == 'complete' || node.readyState == 'loaded') {
												var file = node._originalSrc;
												if (typeof console != 'undefined' && typeof console.log != 'undefined')
													console.log("Retrieved JS file '%s' from server", [file]);

												self.loadedJSFiles[file] = true;
												self.checkLoadFinish();
											}
										};
									}
									else
									{
										this.loadedJSFiles[res.data] = true;
									}
								}
							}
							hasResponse = true;
						} else
							throw 'Invalid parameters';
						break;
					case 'error':
						if (typeof res.data == 'string')
						{
							this.jsonError(res.data);
							hasResponse = true;
						} else
							throw 'Invalid parameters';
						break;
				}

				//Try to handle the json response with all registered plugins
				hasResponse |= _egw_json_plugin_handle(data.response[i].type, res);
			} catch(e) {
				this.jsonError('Internal JSON handler error', e);
			}
		}

		/* If no explicit response has been specified, call the callback (if one was set) */
		if (!hasResponse && this.callback && data.response[i])
		{			
			this.callback.call(this.sender, data.response[i].data);			
		}

		this.handleResponseDone = true;

		this.checkLoadFinish();
	}
}

/**
 * The "onLoadFinish" handler gets called after all JS-files have been loaded
 * successfully
 */
egw_json_request.prototype.checkLoadFinish = function()
{
	var complete = true;
	for (var key in this.loadedJSFiles)
		complete = complete && this.loadedJSFiles[key];

	if (complete && this.onLoadFinish && this.handleResponseDone)
	{
		this.onLoadFinish.call(this.sender);
	}
}

function egw_json_getFormValues(_form, _filterClass)
{
	var elem = null;
	if (typeof _form == 'object')
	{
		elem = _form;
	}
	else
	{
		elem = document.getElementsByName(_form)[0];
	}

	var serialized = new Object;
	if (typeof elem != "undefined" && elem && elem.childNodes)
	{
		if (typeof _filterClass == 'undefined')
			_filterClass = null;

		_egw_json_getFormValues(serialized, elem.childNodes, _filterClass)
	}

	return serialized;
}

/**
 * Deprecated legacy xajax wrapper functions for the new egw_json interface
 */
_xajax_doXMLHTTP = function(_async, _menuaction, _arguments)
{
	/* Assemble the parameter array */
	var paramarray = new Array();
	for (var i = 1; i < _arguments.length; i++)
	{
		paramarray[paramarray.length] = _arguments[i];
	}

	/* Create a new request, passing the menuaction and the parameter array */
	var request = new egw_json_request(_menuaction, paramarray);

	/* Send the request */
	request.sendRequest(_async);

	return request;
}

xajax_doXMLHTTP = function(_menuaction)
{
	return _xajax_doXMLHTTP(true, _menuaction, arguments);
}

xajax_doXMLHTTPsync = function(_menuaction)
{
	return _xajax_doXMLHTTP(false, _menuaction, arguments);
};

window.xajax = {
	"getFormValues": function(_form)
	{
		return egw_json_getFormValues(_form);
	}
};

/*
	The following code is adapted from the xajax project which is licensed under
	the following license
	@copyright Copyright (c) 2005-2007 by Jared White & J. Max Wilson
	@copyright Copyright (c) 2008-2009 by Joseph Woolley, Steffen Konerow, Jared White  & J. Max Wilson
	@license http://www.xajaxproject.org/bsd_license.txt BSD License
*/

/**
 * used internally by the legacy "egw_json_response.getFormValues" to recursively
 * run over all form elements
 * @param serialized is the object which will contain the form data
 * @param children is the children node of the form we're runing over
 * @param string _filterClass if given only return 
 */
function _egw_json_getFormValues(serialized, children, _filterClass)
{
	//alert('_egw_json_getFormValues(,,'+_filterClass+')');
	for (var i = 0; i < children.length; ++i) {
		var child = children[i];

		if (typeof child.childNodes != "undefined")
			_egw_json_getFormValues(serialized, child.childNodes, _filterClass);

		if ((!_filterClass || $(child).hasClass(_filterClass)) && typeof child.name != "undefined")
		{
			//alert('_egw_json_getFormValues(,,'+_filterClass+') calling _egw_json_getFormValue for name='+child.name+', class='+child.class+', value='+child.value);
			_egw_json_getFormValue(serialized, child);
		}
	}
}

function _egw_json_getObjectLength(_obj)
{
	var res = 0;
	for (key in _obj)
	{
		if (_obj.hasOwnProperty(key))
			res++;
	}
	return res;
}

/**
 * used internally to serialize 
 */
function _egw_json_getFormValue(serialized, child)
{
	//Return if the child doesn't have a name, is disabled, or is a radio-/checkbox and not checked
	if ((typeof child.name == "undefined") || (child.disabled && child.disabled == true) ||				
		(child.type && (child.type == 'radio' || child.type == 'checkbox' || child.type == 'button' || child.type == 'submit') && (!child.checked)))
	{
		return;
	}
	
	var name = child.name;
	var values = null;	

 	if ('select-multiple' == child.type)
	{
		values = new Array;
 		for (var j = 0; j < child.length; ++j)
		{
 			var option = child.options[j];
 			if (option.selected == true)
 				values.push(option.value);
 		}
 	}
	else
	{
 		values = child.value;
 	}

	//Special treatment if the name of the child contains a [] - then all theese
	//values are added to an array.
	var keyBegin = name.indexOf('[');
	if (0 <= keyBegin) {
		var n = name;
		var k = n.substr(0, n.indexOf('['));
		var a = n.substr(n.indexOf('['));
		if (typeof serialized[k] == 'undefined')
			serialized[k] = new Object;

		var p = serialized; // pointer reset
		while (a.length != 0) {
			var sa = a.substr(0, a.indexOf(']')+1);
			
			var lk = k; //save last key
			var lp = p; //save last pointer
			
			a = a.substr(a.indexOf(']')+1);
			p = p[k];
			k = sa.substr(1, sa.length-2);
			if (k == '') {
				if ('select-multiple' == child.type) {
					k = lk; //restore last key
					p = lp;
				} else {
					k = _egw_json_getObjectLength(p);
				}
			}
			if (typeof p[k] == 'undefined')
			{
				p[k] = new Object; 
			}
		}
		p[k] = values;
	} else {
		//Add the value to the result object with the given name
		if (typeof values != "undefined")
		{
			serialized[name] = values;
		}
	}
}