/**
 * 2 reducers which are used for composition.
 */
const reduceUpdateEntity = state => state; // Ignore this one
const reduceReplaceEntity = (state, { payload, meta }) => ({
    ...state,
    [meta.model]: {
        ...state[meta.model]
        [meta.entity]: payload,
    },
});

/**
 * Reducer's managed state.
 */
const mainReducerInitialState = {
    collection: {
        animals: [],
        people: [],
        books: [],
    },
};

/**
 * Typical reducer.
 */
const mainReducer = (state = mainReducerInitialState, action) => {
    switch (action.type) {
        case constant.REPLACE_ENTITY:
            return reduceReplaceEntity(state, action);
        case constant.UPDATE_ENTITY:
            return reduceUpdateEntity(state, action);
    }
};

/**
 * Creating Redux store with one main reducer. - Instead of using
 * plain switch statement I'm using 'redux-actions' module from GitHub.
 */
const store = Redux.createStore(
    Redux.CombineReducers({
        main: mainReducer,
    }),
);


store.dispatch({
    type: constant.REPLACE_ENTITY,
    payload: 'replacing animals',
    meta: {
        model: 'collection', // <-- This is where I'd like to reuse my constants
        entity: 'animals', // <-- This is where I'd like to reuse my constants
    },
});