/*--------------------------------------------------------
 * Copyright © 2009 – 2010* France Telecom
 * This software is distributed under the "Simplified BSD license",
 * the text of which is available at http://www.winktoolkit.org/licence.txt
 * or see the "license.txt" file for more details.
 *--------------------------------------------------------*/

/**
 * XHR utility
 * 
 * @methods:
 * 	--> sendData: make an XHR call to the given URL
 * 
 * @attributes:
 * 	--> uId: unique identifier of the component
 * 	--> request: an object containing the actual XMLHttpRequest and optionally parameters
 * 
 * @properties:
 * 	--> properties: parameters that will be stored within the request object and can be used in the callbacks methods
 * 
 * @compatibility:
 * 	--> Iphone OS2, Iphone OS3, Iphone OS4, Android 1.1, Android 1.5, Android 2.1, Android 2.2, Android 2.3, BlackBerry 6, Bada 1.0
 * 
 * @author:
 * 	--> Jerome GIRAUD
 */
(function(wink) {
	
var isSet = wink.isSet;
var isArray = wink.isArray;

wink.net.Xhr = function(properties)
{
	this.uId = wink.getUId();
	
	this.request =
	{
	    xhrObject: null,
	    params: properties
	};

	/**
	 * Initiate the component
	 */
	this._create();
};

wink.net.Xhr.prototype =
{
	/**
	 * Send the datas
	 * 
	 * @parameters:
	 * 	--> url: the URL to call
	 * 	--> parameters: the parameters to add to the request URL
	 * 	--> method: either GET or POST
	 * 	--> successCallback: the method to call in case of success. The 'callback' is an object that must contain a 'method' and a 'scope'
	 * 	--> failureCallback: the method to call in case of success. The 'callback' is an object that must contain a 'method' and a 'scope'
	 * 	--> headers: the HTTP headers to add to the request
	 */
	sendData: function(url, parameters, method, successCallback, failureCallback, headers)
	{
		var r = this.request, xo = r.xhrObject, enc = encodeURIComponent;
	
		method = method.toUpperCase();
		
		if ( isSet(parameters) && !isArray(parameters) )
		{
			wink.log('[Xhr] parameters must be in an array of objects containing the parameter name and value');
			return;
		}
	
		if (xo)
		{
			var p = null;
			
			if ( isSet(parameters) )
			{	
				var i, l = parameters.length;
				
				for (i=0; i<l; i++)
				{
					var parami = parameters[i];
					var name = parami.name;
					var value = parami.value;
					
					if ( method == 'GET' )
					{
						if ( i==0 && url.indexOf('?')==-1)	
						{
							url += '?' + enc(name) + '=' + enc(value);
						} else
						{
							url += '&' + enc(name) + '=' + enc(value);
						}
					} else
					{
						if ( i==0 )
						{
							p = enc(name) + '=' + enc(value);
						} else
						{
							p += '&' + enc(name) + '=' + enc(value);
						}
					}
				}
			}
			
			try
			{
				xo.open(method, url, true);
				xo.setRequestHeader('Content-Type', 'text/xml; charset=utf-8');
				
				if ( isSet(headers) )
  				{
  					if ( !isArray(headers) )
  					{
  						wink.log('[Xhr] headers must be in an array of objects containing the header name and value');
  					} else
  					{
  						var i, l = headers.length;
  						for (i=0; i<l; i++)
  						{
  							var hi = headers[i];
  							xo.setRequestHeader(hi.name, hi.value);
  						}
  					}
  				}
				
				xo.send(p);
				
			} catch (e)
			{
				return false;
			}
				
			xo.onreadystatechange = function()
			{
				var readyState = xo.readyState;
				var status = xo.status;
				if (readyState == 4 && !((status >= 200 && status < 400) || status == 0))
				{
					if ( isSet(failureCallback) )
					{
						wink.call(failureCallback, r);
					}
				}
				if (readyState == 4 && ((status >= 200 && status < 400) || status == 0))
				{
					if ( isSet(successCallback) )
					{
						wink.call(successCallback, r);
					}
				}
			};
		} else
		{
			return false;
		}
	
		return true;
	},

	/**
	 * Instantiate a new XMLHttpRequest
	 */
	_create: function()
	{
		var xhrInterface = window.XMLHttpRequest;
		if (xhrInterface)
		{
			var xo;
			try
			{
				xo = new xhrInterface();
			} catch (e)
			{
				xo = false;
			}
			this.request.xhrObject = xo;
		} else
		{
			wink.log('[Xhr] XHR not supported');
		}
	}
};

//Bindings
wink.Xhr = wink.net.Xhr;

})(wink);