import { ADD_MESSAGE, REMOVE_OLDEST_MESSAGE } from "../actions/message.actions";

const initialState = {
    sortedByTimestamp: []
};

export function messagesReducer(state = initialState, action) {
    switch(action.type) {
        case ADD_MESSAGE:
            return handleAddMessage(state, action);
        case REMOVE_OLDEST_MESSAGE:
            return handleRemoveOldestMessage(state, action);
    };
    return state;
}

function handleAddMessage(state, action) {
    return {
        ...state,
        sortedByTimestamp: [
            { ts: Date.now(), text: action.text, type: action.messageType },
            ...state.sortedByTimestamp
        ]
    }
};

function handleRemoveOldestMessage(state, action) {
    return {
        ...state,
        sortedByTimestamp: state.sortedByTimestamp.slice(0, -1)
    }
};