import { ActionTypes } from '../actions';

const reducer = (state = {}, action) => {
  switch (action.type) {
    case ActionTypes.CHANGE_LOCALE:
      return {
        ...state,
        locale: action.payload.locale,
      };

    case ActionTypes.FETCH_MESSAGES:
      return {
        ...state,
        loading: true,
        error: null,
      };

    case ActionTypes.FETCH_MESSAGES_SUCCESS: {
      const messages = {
        ...state.messages,
        [action.payload.locale]: action.payload.messages,
      };

      return {
        ...state,
        loading: false,
        error: null,
        messages,
      };
    }

    case ActionTypes.FETCH_MESSAGES_ERROR: {
      return {
        ...state,
        loading: false,
        error: action.payload.error,
      };
    }

    default:
      return state;
  }
};

/**
 * Creates a reducer that can be used with [`combineReducer`](http://redux.js.org/docs/api/combineReducers.html)
 */
export default (options = {}) => ({
  [options.domain || 'i18n']: reducer,
});