sidebar & widget state management WIP

src/public/javascripts/services/sidebar.js

@@ -38,14 +38,27 @@ class Sidebar {
         this.$hideSidebarButton.click(() => {
             this.$sidebar.hide();
             this.$showSideBarButton.show();
+            this.ctx.stateChanged();
         });
 
         this.$showSideBarButton.click(() => {
             this.$sidebar.show();
             this.$showSideBarButton.hide();
+            this.ctx.stateChanged();
         });
     }
 
+    isVisible() {
+        return this.$sidebar.is(":visible");
+    }
+
+    getSidebarState() {
+        return {
+            visible: this.isVisible(),
+            widgets: this.widgets.map(w => w.getWidgetState())
+        }
+    }
+
     async noteLoaded() {
         this.widgets = [];
         this.$widgets.empty();