frontend: updates reducer to process serialized values

frontend/src/App.tsx

@@ -8,96 +8,32 @@ import {
 import './App.css';
 import { Notifications } from './components/NotificationsComponent';
 import { ConnectionToast } from './components/ConnectionToast';
+import { SerializedValue, setNestedValueByPath, State } from './utils/stateUtils';
 
-type ValueType = boolean | string | number | object;
-
-type State = DataServiceJSON | null;
 type Action =
-  | { type: 'SET_DATA'; data: DataServiceJSON }
-  | { type: 'UPDATE_ATTRIBUTE'; parentPath: string; name: string; value: ValueType };
+  | { type: 'SET_DATA'; data: State }
+  | {
+      type: 'UPDATE_ATTRIBUTE';
+      parentPath: string;
+      name: string;
+      value: SerializedValue;
+    };
 type UpdateMessage = {
-  data: { parent_path: string; name: string; value: object };
+  data: { parent_path: string; name: string; value: SerializedValue };
 };
 type ExceptionMessage = {
   data: { exception: string; type: string };
 };
 
-/**
- * A function to update a specific property in a deeply nested object.
- * The property to be updated is specified by a path array.
- *
- * Each path element can be a regular object key or an array index of the
- * form "attribute[index]", where "attribute" is the key of the array in
- * the object and "index" is the index of the element in the array.
- *
- * For array indices, the element at the specified index in the array is
- * updated.
- *
- * If the property to be updated is an object or an array, it is updated
- * recursively.
- */
-function updateNestedObject(path: Array<string>, obj: object, value: ValueType) {
-  // Base case: If the path is empty, return the new value.
-  // This means we've reached the nested property to be updated.
-  if (path.length === 0) {
-    return value;
-  }
-
-  // Recursive case: If the path is not empty, split it into the first key and the rest
-  // of the path.
-  const [first, ...rest] = path;
-
-  // Check if 'first' is an array index.
-  const indexMatch = first.match(/^(\w+)\[(\d+)\]$/);
-
-  // If 'first' is an array index of the form "attribute[index]", then update the
-  // element at the specified index in the array. Otherwise, update the property
-  // specified by 'first' in the object.
-  if (indexMatch) {
-    const attribute = indexMatch[1];
-    const index = parseInt(indexMatch[2]);
-
-    if (Array.isArray(obj[attribute]?.value)) {
-      return {
-        ...obj,
-        [attribute]: {
-          ...obj[attribute],
-          value: obj[attribute].value.map((item, i) =>
-            i === index
-              ? {
-                  ...item,
-                  value: updateNestedObject(rest, item.value || {}, value)
-                }
-              : item
-          )
-        }
-      };
-    } else {
-      throw new Error(
-        `Expected ${attribute}.value to be an array, but received ${typeof obj[
-          attribute
-        ]?.value}`
-      );
-    }
-  } else {
-    return {
-      ...obj,
-      [first]: {
-        ...obj[first],
-        value: updateNestedObject(rest, obj[first]?.value || {}, value)
-      }
-    };
-  }
-}
-
 const reducer = (state: State, action: Action): State => {
   switch (action.type) {
     case 'SET_DATA':
       return action.data;
     case 'UPDATE_ATTRIBUTE': {
-      const path = action.parentPath.split('.').slice(1).concat(action.name);
+      const pathList = action.parentPath.split('.').slice(1).concat(action.name);
+      const joinedPath = pathList.join('.');
 
-      return updateNestedObject(path, state, action.value);
+      return setNestedValueByPath(state, joinedPath, action.value);
     }
     default:
       throw new Error();
@@ -137,7 +73,7 @@ const App = () => {
       // Fetch data from the API when the client connects
       fetch(`http://${hostname}:${port}/service-properties`)
         .then((response) => response.json())
-        .then((data: DataServiceJSON) => dispatch({ type: 'SET_DATA', data }));
+        .then((data: State) => dispatch({ type: 'SET_DATA', data }));
       setConnectionStatus('connected');
     });
     socket.on('disconnect', () => {