Show a warning if the user tries to leave the page with unsaved textbook changes

cms/static/coffee/spec/models/textbook_spec.coffee

@@ -26,6 +26,18 @@ describe "CMS.Models.Textbook", ->
     it "should have a URL set", ->
         expect(_.result(@model, "url")).toBeTruthy()
 
+    it "should not be dirty by default", ->
+        expect(@model.isDirty()).toBeFalsy()
+
+    it "should be dirty after it's been changed", ->
+        @model.set("name", "foobar")
+        expect(@model.isDirty()).toBeTruthy()
+
+    it "should not be dirty after calling setOriginalAttributes", ->
+        @model.set("name", "foobar")
+        @model.setOriginalAttributes()
+        expect(@model.isDirty()).toBeFalsy()
+
 
 describe "CMS.Models.Textbook input/output", ->
     # replace with Backbone.Assocations.deepAttributes when

cms/static/js/models/textbook.js

@@ -23,6 +23,9 @@ CMS.Models.Textbook = Backbone.AssociatedModel.extend({
     reset: function() {
         this.set(this._originalAttributes, {parse: true});
     },
+    isDirty: function() {
+        return !_.isEqual(this._originalAttributes, this.parse(this.toJSON()));
+    },
     isEmpty: function() {
         return !this.get('name') && this.get('chapters').isEmpty();
     },

cms/templates/textbooks.html

@@ -30,6 +30,12 @@ $(function() {
     $(".nav-actions .new-button").click(function(e) {
         tbView.addOne(e);
     })
+    $(window).on("beforeunload", function() {
+        var dirty = textbooks.find(function(textbook) { return textbook.isDirty(); });
+        if(dirty) {
+            return "You have unsaved changes. Do you really want to leave this page?";
+        }
+    })
 })
 </script>
 </%block>