// ////////////////////////////////////////////////////////////////////////////

// Symbian Foundation Example Code

//

// This software is in the public domain. No copyright is claimed, and you 

// may use it for any purpose without license from the Symbian Foundation.

// No warranty for any purpose is expressed or implied by the authors or

// the Symbian Foundation. 

// ////////////////////////////////////////////////////////////////////////////

var twitterurl = "http://twitter.com/statuses/user_timeline/21138778.rss";

function Twitter(parentView) {

	this.parentView = parentView;

	this.buttons = null;	

	this.numToShow = 5;

	this.http = null;

}

Twitter.prototype.Update = function(numToShow){

	this.numToShow = numToShow;

	if ( this.buttons == null ) {

		// add the separator

		var separator = new NavigationButton(null, "tweetz-icon.png", "<img src='tweetz.png' border=0>");

		separator.setEnabled(false);

		this.parentView.addControl(separator);

		// create buttons

		this.buttons = new Array();

		for( var i = 0 ; i < this.numToShow; i++ ) {

			var button = new NavigationButton("twitter_button_"+i, null , "");

			this.parentView.addControl(button);

			this.buttons.push(button);

		}

		this.buttons[0].setText("Loading twitter feed...");

	}

	var self = this;

	// get the rss 

	// Prepare synchronous download

	this.http = new Ajax();

    this.http.open("GET", twitterurl , true); // false means synchronous

    this.http.onreadystatechange = function() { self.DoUpdate(); };

    this.http.send(null);

}

Twitter.prototype.DoUpdate = function(){

    if (this.http.readyState == 4) {

		try {

			// Get parsed Doc

			var xmlDoc = this.http.responseXML;

			if (xmlDoc == null) {

				// if the content type is not set correctly, we get the response as text

				var xmlparser = new DOMParser();

				xmlDoc = xmlparser.parseFromString(this.http.responseText, "text/xml");

			}

			var itemElements = xmlDoc.getElementsByTagName("item");

			var loopEnd = Math.min(this.numToShow, itemElements.length);

			// traverse elements and create buttons

			for (var i = 0; i < loopEnd; i++) {

				// iterate through child nodes of this item and gather tweets

				var title = null;

				var date = null;

				node = itemElements[i].firstChild;

				while (node != null) {

					if (node.nodeType == Node.ELEMENT_NODE) {

						if (node.nodeName == "title") {

							// item title

							title = getTextOfNode(node);

						}

						else 

							if (node.nodeName == "pubDate" || node.nodeName == "dc:date") {

								// item publishing date

								date = getTextOfNode(node);

							}

					}

					node = node.nextSibling;

				}

				this.buttons[i].setText("<font size=0.6em><i>" + date + "</i> " + title + "</font>");

				this.buttons[i].setImage("tweet.png");

			}

		} 

		catch (x) {

			this.buttons[0].setText("<font size=0.6em>Uh-Oh! Tweetz not tweeting right now.</font>");

			for (var i = 0; i < this.numToShow; i++) {

				this.buttons[i].setText("");

				this.buttons[i].setImage(null);

			}

		}

	}

}

// Returns the text of a node.

function getTextOfNode(node) {

    var buf = "";

	// iterate through all child elements and collect all text to the buffer

	var child = node.firstChild;

	while (child != null) {

		if (child.nodeType == Node.TEXT_NODE || child.nodeType == Node.CDATA_SECTION_NODE) {

			// append text to buffer

			if (buf != "") {

				buf += " ";

			}

			buf += child.nodeValue;

		}

		child = child.nextSibling;

	}

	// make link if there is a url

	var ind = buf.indexOf("http://");

	var endind = buf.indexOf(" ", ind);

	if ( ind != -1 ) {

		var tmp = buf.substring(0,ind);

		var url = "";

		if ( endind == -1 ) {

			url = buf.substring(ind);

		} else {

			url = buf.substring(ind, endind);

		}

		tmp += "<div class=\"FeedItemLink\">";

        tmp += "<a href=\"JavaScript:void(0)\" onclick=\"openURL('" + url + "'); return false;\">";

		tmp += url + "</a></div>";

		if ( endind != -1 ) {

			tmp += buf.substring(endind);

		}

		buf = tmp;

	}

	return buf;

}