Add ISO 8601 timestamp parsing for legacy browsers.

Would cause legacy browsers (e.g. Safari 4.1.3) to show posts in the
reverse order and the infinite scroll would not be triggered when
scrolling down to the end of the page.

public/javascripts/app/models/post.js

@@ -21,7 +21,31 @@ app.models.Post = Backbone.Model.extend({
   },
 
   timeOf: function(field) {
-    return new Date(this.get(field)) /1000;
+    var timestamp = new Date(this.get(field)) /1000;
+
+    if (isNaN(timestamp)) {
+	timestamp = this.legacyTimeOf(field);
+    }
+
+    return timestamp;
+  },
+
+  legacyTimeOf: function(field) {
+    var iso8601_utc_pattern = /^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(.(\d{3}))?Z$/;
+    var time_components = this.get(field).match(iso8601_utc_pattern);
+    var timestamp = 0;
+
+    if (time_components != null) {
+      if (time_components[8] == undefined) {
+        time_components[8] = 0;
+      }
+
+      timestamp = Date.UTC(time_components[1], time_components[2] - 1, time_components[3],
+                           time_components[4], time_components[5], time_components[6],
+                           time_components[8]);
+    }
+
+    return timestamp /1000;
   },
 
   createReshareUrl : "/reshares",

spec/javascripts/app/views/post_view_spec.js

@@ -119,5 +119,13 @@ describe("app.views.Post", function(){
       })
     })
 
+    context("legacy browsers", function(){
+      it("supports iso8501 utc timestamps", function(){
+        var timestamp = new Date(this.statusMessage.get("created_at")) /1000;
+
+        expect(this.statusMessage.legacyTimeOf("created_at")).toEqual(timestamp);
+      })
+    })
+
   })
 });