Function createReducer

frontend/src/utils/createReducer.ts:55–79

(initialState: () => State, reducers: RH)

 * Utility function to create a reducer and its actions.
 */
export function createReducer<
  State,
  RH extends ReducerHandlers<NoInfer<State>>,
>(initialState: () => State, reducers: RH): ReducerCreatorResult<State, RH> {
  return {
    reducer: (state, action: ReducerActionOf<RH>) => {
      state = state || initialState();
      if (action.type in reducers) {
        return reducers[action.type](state, action.payload);
      }

      Logger.error(`Action type ${action.type} is not defined in reducers.`);
      return state;
    },
    createActions: (dispatch: Dispatch<RH>) => {
      const actions = {} as ReducerActions<RH>;
      for (const type in reducers) {
        (actions as any)[type] = (payload: any) => {
          dispatch({ type, payload } as any);
        };
      }
      return actions;
    },
  };
}

type Middleware<State, RH> = (
  prevState: State,