Refactor panel toggle reducer to be more readable

[MAILPOET-2455]

assets/js/src/form_editor/store/actions.jsx

@@ -61,11 +61,17 @@ export function switchSidebarTab(id) {
   };
 }
 
-export function toggleSidebarPanel(id, isOpened = undefined) {
+/**
+ * Toggle a panel within the sidebar. Use toggleTo to enforce certain state
+ * @param {string} id
+ * @param {string|undefined} toggleTo - possible values 'opened', 'closed'
+ * @return {{toggleTo: string|undefined, id: string, type: string}}
+ */
+export function toggleSidebarPanel(id, toggleTo = undefined) {
   return {
     type: 'TOGGLE_SIDEBAR_PANEL',
     id,
-    isOpened,
+    toggleTo,
   };
 }
 

assets/js/src/form_editor/store/reducers/toggle_sidebar_panel.jsx

@@ -1,13 +1,34 @@
 import { remove } from 'lodash';
 
-export default (state, action) => {
+const getRequiredAction = (openedPanels, panelId, toggleTo) => {
-  const openedPanels = [...state.sidebar.openedPanels];
+  const isPanelOpened = openedPanels.includes(panelId);
-  const isOpenedCurrent = openedPanels.includes(action.id);
+  let requestedToggleState = toggleTo;
-  const isOpenedFinal = action.isOpened !== undefined ? action.isOpened : !isOpenedCurrent;
+  if (requestedToggleState === undefined) {
-  if (isOpenedFinal && !isOpenedCurrent) {
+    requestedToggleState = isPanelOpened ? 'closed' : 'opened';
-    openedPanels.push(action.id);
   }
-  if (!isOpenedFinal && isOpenedCurrent) {
+  if (isPanelOpened && requestedToggleState === 'closed') {
+    return 'close';
+  }
+  if (!isPanelOpened && requestedToggleState === 'opened') {
+    return 'open';
+  }
+  return null;
+};
+
+/**
+ * @param {object} state
+ * @param {{toggleTo: string|undefined, id: string, type: string}} action
+ * @return {object} Modified state object
+ */
+export default (state, action) => {
+  if (action.toggleTo !== undefined && !['opened', 'closed'].includes(action.toggleTo)) {
+    throw new Error(`Unexpected toggleTo value "${action.toggleTo}"`);
+  }
+  const openedPanels = [...state.sidebar.openedPanels];
+  const requiredAction = getRequiredAction(openedPanels, action.id, action.toggleTo);
+  if (requiredAction === 'open') {
+    openedPanels.push(action.id);
+  } else if (requiredAction === 'close') {
     remove(openedPanels, (item) => item === action.id);
   }
   return {