function dateAge(dateString) {
	var ms = new Date().getTime() - Date.parse(dateString);
	var s = ms / 1000;
	if (s <= 1)
		return "just now";
	else if (s <= 60)
		return Math.round(s) + "s ago";

	var m = s / 60;
	if (m <= 60)
		return Math.round(m) + "m ago";

	var h = m / 60;
	if (h <= 24)
		return Math.round(h) + "h ago";

	var d = h / 24;
	return Math.round(d) + "d ago";
}


var pithySubtitles = [
	"find out what people are having for lunch",
	"enjoy quality political discourse",
	"eavesdrop on people's conversations",
	"lern 2 talk leik a teenager",
	"learn effective new pickup lines",
	"see pictures of cats",
    "discover true &lt;3"
];

$(function(){
	var Tweet = Backbone.Model.extend({

		// here's where we're going to add the entities
		parse: function(item) {
			console.log(["Tweet", item]);
			return item;
		}
	});

	var Tweets = Backbone.Collection.extend({
		model: Tweet
	});

	var SearchResult = Backbone.Model.extend({
	   initialize: function() {
		   this.tweets = new Tweets;
		   this.currentClientPage = 1;

		   this.on("add remove change destroy sync", this.update, this);
	   },

		parse: function(response) {
			console.log("Search result:", response);

			// If we're still on page 1 and the query's the same, it means we must have refreshed.
			// So, concatenate our more complete results onto the end of the newer ones.  Preserve next_page
			// so we don't get out-of-order when going backwards.
			if (response.page == 1 && this.get("page") == 1 &&
				response.query == this.get("query")) {

				response.results = response.results.concat(this.get("results"));

				response.next_page = this.get("next_page");
			}

			return response;
		},

		update: function() {
			if (this.currentClientPage <= 0) {
				var url = "http://search.twitter.com/search.json";

				// If we're already on page 1 of the server results and we need to go newer, that means we're
				// doing a refresh -- otherwise we're loading the previous page of results from Twitter.
				if (this.get("page") == 1) {
					this.currentClientPage = 1;
					url += this.get("refresh_url");
				}
				else {
					this.currentClientPage = Math.floor(this.get("results_per_page") / 10);
					url += this.get("previous_page");
				}

				console.log("querying Twitter", url);
				this.fetch({dataType: "jsonp", url: url});

				return;
			}

			var min = (this.currentClientPage - 1) * 10;
			var max = min + 10;

			var currentData = this.get("results");

			if (max > currentData.length) {
				this.currentClientPage = 1;
				var url = "http://search.twitter.com/search.json";
				url += this.get("next_page");

				console.log("querying Twitter", url);
				this.fetch({dataType: "jsonp", url: url});
				return;
			}

			var part = this.get("results").slice(min, max);
			this.tweets.reset(part);
		},

		search: function(hashtag) {
			var url = "http://search.twitter.com/search.json?q=";
			url += encodeURIComponent("#" + hashtag);
			url += "&rpp=100";

			console.log("querying Twitter", url);
			this.fetch({dataType: "jsonp", url: url});
		},

		older: function() {
			this.currentClientPage++;
			this.update();
		},

		newer: function() {
			this.currentClientPage--;
			this.update();
		}
	});

	var TweetView = Backbone.View.extend({
		tagName : "li",
		template : _.template($("#tweet_template").html()),

		render: function() {
			this.$el.html(this.template(this.model.toJSON()));
			return this;
		 }
	});

	var TweetsView = Backbone.View.extend({
		initialize: function() {
			this.model.on("add remove change destroy reset sync", this.render, this);
		},

		render: function() {
			var container = this.$el;
			if (container == null)
				return this;

			container.empty();
			this.model.each(function(tweet){
				var tv = new TweetView({model: tweet});
				tv.render().$el.appendTo(container);
			});

			return this;
		}
	});

	var AppView = Backbone.View.extend({

		events: {
			"click #searchButton": "doSearch",
			"click .pager .older" : "older",
			"click .pager .newer" : "newer"
		},

		initialize: function() {
			this.searchInput = this.$("#hashSearch");
		},

		doSearch: function(e) {
			var sr = this.searchResult = new SearchResult;
			this.tweetView = new TweetsView({model: sr.tweets, el: this.$("#tweets")});
			sr.search(this.searchInput.val());
		},

		older: function(e) {
			this.searchResult.older();
			return false;
		},

		newer: function(e) {
			this.searchResult.newer();
			return false;
		}
	});

	var App = new AppView({el: $("#twitterSearchApp")});
});