Chat/src/reducers/chat.js

function chatReducer(state = {}, { type, chat_id, title, createdAt, lastModified, avatar, members, messages, msg_id, msg_text, msg_createdAt, msg_owner, msg_media, msg_replies }) {
    if (type === 'ADD_CHAT') {
        return {
            ...state,

            [chat_id]: {
                title,
                createdAt,
                lastModified,
                avatar,
                messages,
                members
            }
        }
    }

    if (type === "EDIT_CHAT") {
        return {
            ...state,

            [chat_id]: {
                title: title || state[chat_id].title,
                createdAt: state[chat_id].createdAt,
                lastModified: state[chat_id].lastModified,
                avatar: avatar || state[chat_id].avatar,
                messages: state[chat_id].messages,
                members: members || state[chat_id].members
            }
        }
    }

    if (type === "ADD_MESSAGE") {
        if ((state[chat_id]?.messages?.filter(msg => msg._id === msg_id).length === 0)) {
            return {
                ...state,

                [chat_id]: {
                    title: state[chat_id].title,
                    createdAt: state[chat_id].createdAt,
                    lastModified: msg_createdAt,
                    avatar: state[chat_id].avatar,
                    messages: [...state[chat_id].messages, { _id: msg_id, text: msg_text, createdAt: msg_createdAt, owner: msg_owner, media: msg_media, replies: msg_replies }],
                    members: state[chat_id].members
                }
            }
        }
    }

    if (type === "EDIT_MESSAGE") {
        let order;

        for (let key in state[chat_id].messages) {
            if (state[chat_id].messages[key]._id === messages[0]._id) {
                order = key
            }
        }

        return {
            ...state,

            [chat_id]: {
                title: state[chat_id].title,
                createdAt: state[chat_id].createdAt,
                lastModified,
                avatar: state[chat_id].avatar,
                messages: [
                    ...state[chat_id].messages,

                    state[chat_id].messages[order].text = msg_text,
                    state[chat_id].messages[order].modified = true
                ],
                members: state[chat_id].members
            }
        }
    }
    return state
}

export default chatReducer