eggheadio-projects/getting-started-with-redux: null

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JS Bin</title>
  <script src="https://wzrd.in/standalone/expect@22.4.3"></script>
  <script src="https://unpkg.com/redux@4.0.0/dist/redux.js"></script>
</head>
<body>

</body>
</html>

/*
 * Open the console
 * to see the state log.
 */

const todo = (state, action) => {
  switch (action.type) {
    case 'ADD_TODO':
      return {
        id: action.id,
        text: action.text,
        completed: false
      };
    case 'TOGGLE_TODO':
      if (state.id !== action.id) {
        return state;
      }

      return {
        ...state,
        completed: !state.completed
      };
    default:
      return state;
  }
};

const todos = (state = [], action) => {
  switch (action.type) {
    case 'ADD_TODO':
      return [
        ...state,
        todo(undefined, action)
      ];
    case 'TOGGLE_TODO':
      return state.map(t => todo(t, action));
    default:
      return state;
  }
};

const visibilityFilter = (
  state = 'SHOW_ALL',
  action
) => {
  switch (action.type) {
    case 'SET_VISIBILITY_FILTER':
      return action.filter;
    default:
      return state;
  }
};

const combineReducers = (reducers) => {
  return (state = {}, action) => {
    return Object.keys(reducers).reduce(
      (nextState, key) => {
        nextState[key] = reducers[key](
          state[key],
          action
        );
        return nextState;
      },
      {}
    );
  };
};

const todoApp = combineReducers({
  todos,
  visibilityFilter
});

const { createStore } = Redux;
const store = createStore(todoApp);

console.log('Initial state:');
console.log(store.getState());
console.log('--------------');

console.log('Dispatching ADD_TODO.');
store.dispatch({
  type: 'ADD_TODO',
  id: 0,
  text: 'Learn Redux'
});
console.log('Current state:');
console.log(store.getState());
console.log('--------------');

console.log('Dispatching ADD_TODO.');
store.dispatch({
  type: 'ADD_TODO',
  id: 1,
  text: 'Go shopping'
});
console.log('Current state:');
console.log(store.getState());
console.log('--------------');

console.log('Dispatching TOGGLE_TODO.');
store.dispatch({
  type: 'TOGGLE_TODO',
  id: 0
});
console.log('Current state:');
console.log(store.getState());
console.log('--------------');

console.log('Dispatching SET_VISIBILITY_FILTER');
store.dispatch({
  type: 'SET_VISIBILITY_FILTER',
  filter: 'SHOW_COMPLETED'
});
console.log('Current state:');
console.log(store.getState());
console.log('--------------');