/**
 * 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_encode(input)
{
	if (!input) return 'null';

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

		case Number:
			return input.toString();

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

		case Array :
			var buf = [];
			for (var i = 0; i < input.length; i++)
				buf.push(egw_json_encode(input[i]));
			return '[' + buf.join(',') + ']';

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

		default:
			return 'null';
	}
}


/* The constructor of the egw_json_request class.
 * @param string _menuaction the menuaction function which should be called and which handles the actual request
 * @param array _parameters which should be passed to the menuaction function.
*/
function egw_json_request(_menuaction, _parameters)
{
	//Copy the supplied parameters
	this.menuaction = _menuaction;

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

	var url = window.egw_webserverUrl;

	// Search up to parent if the current window is in a frame
	if(typeof url == "undefined")
	{
		url = top.egw_webserverUrl;
	}

	this.url = url + '/json.php';

	this.sender = null;
	this.callback = null;
	this.alertHandler = this.alertFunc;
	if (window.egw_alertHandler)
	{
		this.alertHandler = window.egw_alertHandler;
	}
}

/* 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
	$.ajax({url: this.url + '?menuaction=' + this.menuaction,
		async: is_async,
		context: this,
		data: request_obj,
		dataType: 'json',
		type: 'POST', 
		success: this.handleResponse});
}

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

/* Internal function which handles the response from the server */
egw_json_request.prototype.handleResponse = function(data, textStatus, XMLHttpRequest)
{
	if (data && data.response)
	{
		var hasResponse = false;
		for (var i = 0; i < data.response.length; i++)
		{
			switch (data.response[i].type)
			{
				case 'alert':
					//Check whether all needed parameters have been passed and call the alertHandler function
					if ((typeof data.response[i].data.message != 'undefined') && 
						(typeof data.response[i].data.details != 'undefined'))
					{					
						this.alertHandler(
							data.response[i].data.message,
							data.response[i].data.details)
						hasResponse = true;
					}
					break;
				case 'assign':
					//Check whether all needed parameters have been passed and call the alertHandler function
					if ((typeof data.response[i].data.id != 'undefined') && 
						(typeof data.response[i].data.key != 'undefined') &&
						(typeof data.response[i].data.value != 'undefined'))
					{					
						var obj = document.getElementById(data.response[i].data.id);
						if (obj)
						{
							obj[data.response[i].data.key] = data.response[i].data.value;
							hasResponse = true;
						}
					}
					break;
				case 'data':
					//Callback the caller in order to allow him to handle the data
					if (this.callback)
					{
						this.callback.call(this.sender, data.response[i].data);
						hasResponse = true;
					}
					break;
				case 'script':
					if (typeof data.response[i].data == 'string')
					{
						try
						{
							var func = function() {eval(data.response[i].data);};
							func.call(window);
						}
						catch (e)
						{
							if (typeof console != "undefined" && typeof console.log != "undefined")
							{
								e.code = data.response[i].data;
								console.log(e);
							}
						}
						hasResponse = true;
					}
					break;
				case 'each':
					if (typeof data.response[i].select == 'string' && typeof data.response[i].func == 'string')
					{
						try
						{
							var func = data.response[i].func;
							// todo: for N>2
							$(data.response[i].select).each(func.call(data.response[i].parms[0],data.response[i].parms[1],data.response[i].parms[2]));
						}
						catch (e)
						{
							if (typeof console != "undefined" && typeof console.log != "undefined")
							{
								e.code = data.response[i];
								console.log(e);
							}
						}
						hasResponse = true;
					}
					break;
				case 'redirect':
					if (typeof data.response[i].data == 'string')
					{
						window.location.href = data.response[i].data;
					}
					break;
			}
		}

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



/**
 * 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)
	{		
		var elem = null;
		if (typeof _form == 'object')
		{
			elem = _form;
		}
		else
		{
			elem = document.getElementsByName(_form)[0];
		}

		var serialized = $(_form).serializeArray();
		alert("\nSerialized:\n" + serialized);
		return serialized;
	}
};*/