reducer.ts

import type { Action } from "./actions";

export const initialState = {
  content: "Hello World",
  background: "#ffcc00"
};

export type Store = typeof initialState;

export const reducer = (state: Store, action: Action) => {
  switch (action.type) {
    case "SET_BACKGROUND_COLOR":
      const background = action.payload.background

      return { ...state, background };
    case "SET_CONTENT":
      const content = action.payload.content;

      return { ...state, content };
    default:
      return state;
  }
};