var gfeedfetcher_loading_image="http://www.pikatechnologies.com/appliance/loading.gif";

google.load("feeds", "1"); //Load Google Ajax Feed API (version 1)

function gfeedfetcher(divid, divClass, linktarget)
{
	this.linktarget=linktarget || ""; //link target of RSS entries
	this.feedlabels=[]; //array holding lables for each RSS feed
	this.feedurls=[];
	this.feeds=[]; //array holding combined RSS feeds' entries from Feed API (result.feed.entries)
	this.feedsfetched=0; //number of feeds fetched
	this.feedlimit=5;
	this.showoptions=""; //Optional components of RSS entry to show (none by default)
	this.sortstring="date"; //sort by "date" by default
	document.write('<div id="'+divid+'" class="'+divClass+'"></div>'); //output div to contain RSS entries
	this.feedcontainer=document.getElementById(divid);
	this.itemcontainer="<li>"; //default element wrapping around each RSS entry item
}

gfeedfetcher.prototype.addFeed=function(label, url)
{
	this.feedlabels[this.feedlabels.length]=label;
	this.feedurls[this.feedurls.length]=url;
}

gfeedfetcher.prototype.filterfeed=function(feedlimit, sortstr)
{
	this.feedlimit=feedlimit;
	if (typeof sortstr!="undefined")
	{
		this.sortstring=sortstr;
	}
}

gfeedfetcher.prototype.displayoptions=function(parts)
{
	this.showoptions=parts; //set RSS entry options to show ("date, datetime, time, snippet, label, description")
}

gfeedfetcher.prototype.setentrycontainer=function(containerstr)
{  //set element that should wrap around each RSS entry item
	this.itemcontainer="<"+containerstr.toLowerCase()+">";
}

gfeedfetcher.prototype.init=function()
{
	this.feedsfetched=0; //reset number of feeds fetched to 0 (in case init() is called more than once)
	this.feeds=[]; //reset feeds[] array to empty (in case init() is called more than once)
	this.feedcontainer.innerHTML='<img src="'+gfeedfetcher_loading_image+'" /> Retrieving RSS feed(s)';
	var displayer=this;
	for (var i=0; i<this.feedurls.length; i++)
	{ //loop through the specified RSS feeds' URLs
		var feedpointer=new google.feeds.Feed(this.feedurls[i]); //create new instance of Google Ajax Feed API
		var items_to_show=(this.feedlimit<=this.feedurls.length)? 1 : Math.floor(this.feedlimit/this.feedurls.length); //Calculate # of entries to show for each RSS feed
		if (this.feedlimit%this.feedurls.length>0 && this.feedlimit>this.feedurls.length && i==this.feedurls.length-1) //If this is the last RSS feed, and feedlimit/feedurls.length yields a remainder
		{			
      items_to_show+=(this.feedlimit%this.feedurls.length); //Add that remainder to the number of entries to show for last RSS feed
		}
		feedpointer.setNumEntries(items_to_show); //set number of items to display
		feedpointer.load(function(r){displayer._fetch_data_as_array(r)}); //call Feed.load() to retrieve and output RSS feed
	}
}


gfeedfetcher._formatdate=function(datestr, showoptions)
{
	var itemdate=new Date(datestr);
	var parseddate=(showoptions.indexOf("datetime")!=-1)? itemdate.toLocaleString() : (showoptions.indexOf("date")!=-1)? itemdate.toLocaleDateString() : (showoptions.indexOf("time")!=-1)? itemdate.toLocaleTimeString() : "";
	return "<span class='datefield'>"+parseddate+"</span>";
}

gfeedfetcher._sortarray=function(arr, sortstr)
{
	var sortstr=(sortstr=="label")? "ddlabel" : sortstr; //change "label" string (if entered) to "ddlabel" instead, for internal use
	if (sortstr=="title" || sortstr=="ddlabel")
	{
		//sort array by "title" or "ddlabel" property of RSS feed entries[]
		arr.sort(function(a,b)
		{
			var fielda=a[sortstr].toLowerCase();
			var fieldb=b[sortstr].toLowerCase();
			return (fielda<fieldb)? -1 : (fielda>fieldb)? 1 : 0;
		});
	}
	else
	{ 
    //else, sort by "publishedDate" property (using error handling, as "publishedDate" may not be a valid date str if an error has occured while getting feed
		try
		{
			arr.sort(function(a,b){return new Date(b.publishedDate)-new Date(a.publishedDate)});
		}
		catch(err)
		{
    }
	}
}

gfeedfetcher.prototype._fetch_data_as_array=function(result)
{
	var thisfeed=(!result.error)? result.feed.entries : ""; //get all feed entries as a JSON array or "" if failed
	if (thisfeed=="")
	{ 
		//if error has occured fetching feed
		alert("Google Feed API Error: " + result.error.message);
	}

	for (var i=0; i<thisfeed.length; i++) //For each entry within feed
	{
		result.feed.entries[i].ddlabel=this.feedlabels[this.feedsfetched]; //extend it with a "ddlabel" property
	}
	this.feeds=this.feeds.concat(thisfeed); //add entry to array holding all feed entries
	this._signaldownloadcomplete(); //signal the retrieval of this feed as complete (and move on to next one if defined)
}

gfeedfetcher.prototype._signaldownloadcomplete=function()
{
	this.feedsfetched+=1;
	if (this.feedsfetched==this.feedurls.length)
	{
		//if all feeds fetched
		this._displayresult(this.feeds); //display results
	}
}

gfeedfetcher.removeTagsFromStr=function(aFeedContentStr)
{
  //alert(aFeedContentStr.replace(/<[\s\S]*?>/g, " "))
  var newContent = aFeedContentStr.replace(/<[\s\S]*?>/g, " ");
	newContent = newContent.replace(/\s(\s)+/g, " ");
  //alert(newContent)
  return newContent;
}

gfeedfetcher.getSpecifiedNumOfWords=function(aString, numOfWords)
{
	var newString = "";
	var arrayOfWords = aString.split(" ", numOfWords);

	for (var i=0; i < arrayOfWords.length; i++)
	{
		newString = newString + arrayOfWords[i] + " ";
	}

	return newString;
}

gfeedfetcher.prototype._displayresult=function(feeds)
{
	var rssoutput=(this.itemcontainer=="<li>")? "<ul>\n" : "";
	gfeedfetcher._sortarray(feeds, this.sortstring);
	for (var i=0; i<feeds.length; i++)
	{
		var itemtitle="<a href=\"" + feeds[i].link + "\" target=\"" + this.linktarget + "\" class=\"titlefield\">" + feeds[i].title + "</a>";
		var itemlabel=/label/i.test(this.showoptions)? '<span class="labelfield">['+this.feeds[i].ddlabel+']</span>' : " ";
		var itemdate= "<br />" + gfeedfetcher._formatdate(feeds[i].publishedDate, this.showoptions) + "<br />";


		var itemdescription=/description/i.test(this.showoptions)? "<br />"+ gfeedfetcher.getSpecifiedNumOfWords(gfeedfetcher.removeTagsFromStr(feeds[i].content),60) + "[...]" : /snippet/i.test(this.showoptions)? "<br />"+feeds[i].contentSnippet  : "";
		rssoutput+=this.itemcontainer + itemtitle + " " + itemlabel + "" + itemdate + "\n" + itemdescription + this.itemcontainer.replace("<", "</") + "\n\n";
		//alert(rssoutput);
		rssoutput =  rssoutput + "<br /><hr size=1 noshade />";
	}
	rssoutput+=(this.itemcontainer=="<li>")? "</ul>" : "";
	//alert(rssoutput);
	this.feedcontainer.innerHTML=rssoutput;
}