Show time ago in comments

app/assets/javascripts/application.js

@@ -8,6 +8,7 @@
 //= require jquery_ujs
 //= require vendor/underscore-min
 //= require vendor/backbone-min
+//= require vendor/jquery.timeago
 //= require handlebars.runtime
 //= require backbone/ascii_io
 //= require player/player

app/assets/javascripts/backbone/views/comments/comment_entry.js.coffee

@@ -11,13 +11,19 @@ class AsciiIo.Views.CommentEntry extends AsciiIo.Views.Base
     @collection = options.collection
 
   render: ->
-    context = _.extend(@model.toJSON(), { show_remove_link: @showRemoveLink() })
+    context = _.extend( @model.toJSON(), { 
+      show_remove_link: @showRemoveLink(),
+      created: @timeAgo() } )
+
     $(@el).html @template(context)
     this
 
   showRemoveLink: ->
     @current_user() && ( @current_user().id == @model.user().id )
 
+  timeAgo: ->
+    $.timeago( @model.get('created') )
+
   removeComment: (event) ->
     event.preventDefault()
     @model.destroy

app/assets/javascripts/vendor/jquery.timeago.js

@@ -0,0 +1,147 @@
+/**
+ * Timeago is a jQuery plugin that makes it easy to support automatically
+ * updating fuzzy timestamps (e.g. "4 minutes ago" or "about 1 day ago").
+ *
+ * @name timeago
+ * @version 0.10.1
+ * @requires jQuery v1.2.3+
+ * @author Ryan McGeary
+ * @license MIT License - http://www.opensource.org/licenses/mit-license.php
+ *
+ * For usage and examples, visit:
+ * http://timeago.yarp.com/
+ *
+ * Copyright (c) 2008-2011, Ryan McGeary (ryanonjavascript -[at]- mcgeary [*dot*] org)
+ */
+(function($) {
+  $.timeago = function(timestamp) {
+    if (timestamp instanceof Date) {
+      return inWords(timestamp);
+    } else if (typeof timestamp === "string") {
+      return inWords($.timeago.parse(timestamp));
+    } else {
+      return inWords($.timeago.datetime(timestamp));
+    }
+  };
+  var $t = $.timeago;
+
+  $.extend($.timeago, {
+    settings: {
+      refreshMillis: 60000,
+      allowFuture: false,
+      strings: {
+        prefixAgo: null,
+        prefixFromNow: null,
+        suffixAgo: "ago",
+        suffixFromNow: "from now",
+        seconds: "less than a minute",
+        minute: "about a minute",
+        minutes: "%d minutes",
+        hour: "about an hour",
+        hours: "about %d hours",
+        day: "a day",
+        days: "%d days",
+        month: "about a month",
+        months: "%d months",
+        year: "about a year",
+        years: "%d years",
+        wordSeparator: " ",
+        numbers: []
+      }
+    },
+    inWords: function(distanceMillis) {
+      var $l = this.settings.strings;
+      var prefix = $l.prefixAgo;
+      var suffix = $l.suffixAgo;
+      if (this.settings.allowFuture) {
+        if (distanceMillis < 0) {
+          prefix = $l.prefixFromNow;
+          suffix = $l.suffixFromNow;
+        }
+      }
+
+      var seconds = Math.abs(distanceMillis) / 1000;
+      var minutes = seconds / 60;
+      var hours = minutes / 60;
+      var days = hours / 24;
+      var years = days / 365;
+
+      function substitute(stringOrFunction, number) {
+        var string = $.isFunction(stringOrFunction) ? stringOrFunction(number, distanceMillis) : stringOrFunction;
+        var value = ($l.numbers && $l.numbers[number]) || number;
+        return string.replace(/%d/i, value);
+      }
+
+      var words = seconds < 45 && substitute($l.seconds, Math.round(seconds)) ||
+        seconds < 90 && substitute($l.minute, 1) ||
+        minutes < 45 && substitute($l.minutes, Math.round(minutes)) ||
+        minutes < 90 && substitute($l.hour, 1) ||
+        hours < 24 && substitute($l.hours, Math.round(hours)) ||
+        hours < 48 && substitute($l.day, 1) ||
+        days < 30 && substitute($l.days, Math.floor(days)) ||
+        days < 60 && substitute($l.month, 1) ||
+        days < 365 && substitute($l.months, Math.floor(days / 30)) ||
+        years < 2 && substitute($l.year, 1) ||
+        substitute($l.years, Math.floor(years));
+
+      return $.trim([prefix, words, suffix].join($l.wordSeparator));
+    },
+    parse: function(iso8601) {
+      var s = $.trim(iso8601);
+      s = s.replace(/\.\d\d\d+/,""); // remove milliseconds
+      s = s.replace(/-/,"/").replace(/-/,"/");
+      s = s.replace(/T/," ").replace(/Z/," UTC");
+      s = s.replace(/([\+\-]\d\d)\:?(\d\d)/," $1$2"); // -04:00 -> -0400
+      return new Date(s);
+    },
+    datetime: function(elem) {
+      // jQuery's `is()` doesn't play well with HTML5 in IE
+      var isTime = $(elem).get(0).tagName.toLowerCase() === "time"; // $(elem).is("time");
+      var iso8601 = isTime ? $(elem).attr("datetime") : $(elem).attr("title");
+      return $t.parse(iso8601);
+    }
+  });
+
+  $.fn.timeago = function() {
+    var self = this;
+    self.each(refresh);
+
+    var $s = $t.settings;
+    if ($s.refreshMillis > 0) {
+      setInterval(function() { self.each(refresh); }, $s.refreshMillis);
+    }
+    return self;
+  };
+
+  function refresh() {
+    var data = prepareData(this);
+    if (!isNaN(data.datetime)) {
+      $(this).text(inWords(data.datetime));
+    }
+    return this;
+  }
+
+  function prepareData(element) {
+    element = $(element);
+    if (!element.data("timeago")) {
+      element.data("timeago", { datetime: $t.datetime(element) });
+      var text = $.trim(element.text());
+      if (text.length > 0) {
+        element.attr("title", text);
+      }
+    }
+    return element.data("timeago");
+  }
+
+  function inWords(date) {
+    return $t.inWords(distance(date));
+  }
+
+  function distance(date) {
+    return (new Date().getTime() - date.getTime());
+  }
+
+  // fix for IE6 suckage
+  document.createElement("abbr");
+  document.createElement("time");
+}(jQuery));

app/models/comment.rb

@@ -10,7 +10,7 @@ class Comment < ActiveRecord::Base
   attr_accessible :body
 
   def created
-    created_at.to_s
+    created_at && created_at.strftime("%Y-%m-%dT%H:%M:%S")
   end
 
   def as_json(options = {})

spec/models/comment_spec.rb

@@ -27,4 +27,22 @@ describe Comment do
     end
   end
 
+  describe "#created" do
+    let(:time) { Time.new(2012, 01, 03) }
+    let(:expected) { time.strftime("%Y-%m-%dT%H:%M:%S") }
+    let(:comment) { Factory.build(:comment) }
+
+    context "when created_at present" do
+      before { comment.stub(:created_at).and_return(time) }
+
+      it "returns js parsable format" do
+        comment.created.should == expected
+      end
+    end
+
+    context "no created_at" do
+      it { comment.created_at.should be_nil }
+    end
+
+  end
 end