//create a namespace for this example:

YAHOO.namespace("example.GetNews");

//This example uses the "Module Pattern"; a full explanation of 

//this pattern can be found on yuiblog:

// http://yuiblog.com/blog/2007/06/12/module-pattern

YAHOO.example.GetNews = function() {

	//set up some shortcuts in case our typing fingers

	//get lazy:

	var Event = YAHOO.util.Event,

		Dom = YAHOO.util.Dom,

		JSON = YAHOO.lang.JSON,

		Button = YAHOO.widget.Button,

		Get = YAHOO.util.Get,

		elResults = Dom.get("results");

	//we won't use the Get Utility's success handler in this example

	//because the web service we're using has a built-in callback

	//mechanism.  But we'll stub it out here and use it to simply

	//log a message to the logger:

	var onGetNewsSuccess = function() {

		YAHOO.log("The Get Utility has fired the success handler indicating that the requested script has loaded and is ready for use.", "info", "example");

	}

	//function to retrieve data from Yahoo! News Search web service --

	//http://developer.yahoo.com/search/news/V1/newsSearch.html

	var getNewsData = function() {

		YAHOO.log("Button clicked; getGetNewsData firing.", "info", "example");

		//Load the transitional state of the results section:

		elResults.innerHTML = "<h3>Retrieving news search results for for " +

			Dom.get("searchString").value + ":</h3>" +

			"<img src='http://l.yimg.com/a/i/nt/ic/ut/bsc/busybar_1.gif' " +

			"alt='Please wait...'>";

		//prepare the URL for the Yahoo Site Explorer API:

		var sURL = "http://search.yahooapis.com/NewsSearchService/V1/newsSearch?" +

			"appid=3wEDxLHV34HvAU2lMnI51S4Qra5m.baugqoSv4gcRllqqVZm3UrMDZWToMivf5BJ3Mom" +

			"&results=10&output=json&" +

			"&callback=YAHOO.example.GetNews.callback" +

			"&query=" + encodeURIComponent(Dom.get("searchString").value);

		//This simple line is the call to the Get Utility; we pass

		//in the URL and the configuration object, which in this case

		//consists merely of our success and failure callbacks:

		var transactionObj = Get.script(sURL, {

			onSuccess: onGetNewsSuccess,

			scope    : this

		});

		//The script method returns a single-field object containing the

		//tranaction id:

		YAHOO.log("Get Utility transaction started; transaction object: " + YAHOO.lang.dump(transactionObj), "info", "example");

	}

	return {

		init: function() {

			//suppress default form behavior

			Event.on("newsSearch", "submit", function(e) {

				Event.preventDefault(e);

				getNewsData();

			}, this, true);

			//instantiate Button:

			var oButton = new Button("getNewsData");

			YAHOO.log("GetNews Button instantiated.", "info", "example");

			getNewsData();

		},

		callback: function(results) {

			YAHOO.log("Web service returned data to YAHOO.example.GetNews.callback; beginning to process.", "info", "example");

			//work with the returned data to extract meaningful fields:

			var aResults = results.ResultSet.Result;

			var totalLinks = results.ResultSet.totalResultsAvailable;

			var returnedLinkCount = results.ResultSet.totalResultsReturned;

			if(returnedLinkCount) {//there are inbound links; process and display them:

				//write header and open list of inbound links:			

				var html = "<h3>There are " +

					totalLinks + 

					" news items on this topic; here are the first " + 

					returnedLinkCount +

					":</h3><ol>";

				//process list of inbound links:

				for (var i=0; i < aResults.length; i++) {

					html += "<li><strong><a href='" +

						aResults[i].Url +

						"'>" + aResults[i].Title +

						"</a>:</strong> " + aResults[i].Summary +

						"</li>";

				}

				//close list of inbound links

				html += "</ol>";

			} else {//no inbound links exist for this page:

				var html = "<h3>There are no news items available for the topic specified.</h3";

			}

			//insert string into DOM:

			elResults.innerHTML = html;			

		}

	}

}();

//Initialize the example when the DOM is completely loaded:

YAHOO.util.Event.onDOMReady(

	YAHOO.example.GetNews.init, 

	YAHOO.example.GetNews, 		//pass this object to init and...

	true);								//...run init in the passed object's

										//scope