// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
// See LICENSE.txt for license information.

import {Model, Q} from '@nozbe/watermelondb';

import {updateRecentCustomStatuses, updateUserPresence} from '@actions/local/user';
import {fetchRolesIfNeeded} from '@actions/remote/role';
import {Database, General} from '@constants';
import DatabaseManager from '@database/manager';
import {debounce} from '@helpers/api/general';
import NetworkManager from '@init/network_manager';
import {queryCurrentUserId, queryWebSocketLastDisconnected} from '@queries/servers/system';
import {prepareUsers, queryAllUsers, queryCurrentUser, queryUsersById, queryUsersByUsername} from '@queries/servers/user';

import {forceLogoutIfNecessary} from './session';

import type {Client} from '@client/rest';
import type ClientError from '@client/rest/error';
import type UserModel from '@typings/database/models/servers/user';

export type MyUserRequest = {
    user?: UserProfile;
    error?: unknown;
}

export type ProfilesPerChannelRequest = {
    data?: ProfilesInChannelRequest[];
    error?: unknown;
}

export type ProfilesInChannelRequest = {
    users?: UserProfile[];
    channelId: string;
    error?: unknown;
}

export const fetchMe = async (serverUrl: string, fetchOnly = false): Promise<MyUserRequest> => {
    let client;
    try {
        client = NetworkManager.getClient(serverUrl);
    } catch (error) {
        return {error};
    }

    try {
        const user = await client.getMe();

        if (!fetchOnly) {
            const operator = DatabaseManager.serverDatabases[serverUrl]?.operator;
            if (operator) {
                operator.handleUsers({users: [user], prepareRecordsOnly: false});
            }
        }

        return {user};
    } catch (error) {
        await forceLogoutIfNecessary(serverUrl, error as ClientErrorProps);
        return {error};
    }
};

export const fetchProfilesInChannel = async (serverUrl: string, channelId: string, excludeUserId?: string, fetchOnly = false): Promise<ProfilesInChannelRequest> => {
    let client: Client;
    try {
        client = NetworkManager.getClient(serverUrl);
    } catch (error) {
        return {channelId, error};
    }

    try {
        const users = await client.getProfilesInChannel(channelId);
        const uniqueUsers = Array.from(new Set(users));
        if (!fetchOnly) {
            const operator = DatabaseManager.serverDatabases[serverUrl]?.operator;
            if (operator) {
                const prepare = prepareUsers(operator, uniqueUsers.filter((u) => u.id !== excludeUserId));
                if (prepare) {
                    const models = await prepare;
                    if (models.length) {
                        await operator.batchRecords(models);
                    }
                }
            }
        }

        return {channelId, users: uniqueUsers};
    } catch (error) {
        forceLogoutIfNecessary(serverUrl, error as ClientError);
        return {channelId, error};
    }
};

export const fetchProfilesPerChannels = async (serverUrl: string, channelIds: string[], excludeUserId?: string, fetchOnly = false): Promise<ProfilesPerChannelRequest> => {
    try {
        const requests = channelIds.map((id) => fetchProfilesInChannel(serverUrl, id, excludeUserId, true));
        const data = await Promise.all(requests);

        if (!fetchOnly) {
            const operator = DatabaseManager.serverDatabases[serverUrl]?.operator;
            if (operator) {
                const users = new Set<UserProfile>();
                for (const item of data) {
                    if (item.users?.length) {
                        item.users.forEach(users.add, users);
                    }
                }
                const prepare = prepareUsers(operator, Array.from(users).filter((u) => u.id !== excludeUserId));
                if (prepare) {
                    const models = await prepare;
                    if (models.length) {
                        await operator.batchRecords(models);
                    }
                }
            }
        }

        return {data};
    } catch (error) {
        return {error};
    }
};

export const updateMe = async (serverUrl: string, user: UserModel) => {
    const database = DatabaseManager.serverDatabases[serverUrl]?.database;
    const operator = DatabaseManager.serverDatabases[serverUrl]?.operator;
    if (!database) {
        return {error: `${serverUrl} database not found`};
    }

    let client;
    try {
        client = NetworkManager.getClient(serverUrl);
    } catch (error) {
        return {error};
    }

    let data: UserProfile;
    try {
        data = await client.patchMe(user._raw);
    } catch (e) {
        forceLogoutIfNecessary(serverUrl, e as ClientError);
        return {error: e};
    }

    if (data) {
        operator.handleUsers({prepareRecordsOnly: false, users: [data]});

        const updatedRoles: string[] = data.roles.split(' ');
        if (updatedRoles.length) {
            await fetchRolesIfNeeded(serverUrl, updatedRoles);
        }
    }

    return {data};
};

let ids: string[] = [];
const debouncedFetchStatusesByIds = debounce((serverUrl: string) => {
    fetchStatusByIds(serverUrl, [...new Set(ids)]);
}, 200, false, () => {
    ids = [];
});

export const fetchStatusInBatch = (serverUrl: string, id: string) => {
    ids = [...ids, id];
    return debouncedFetchStatusesByIds.apply(null, [serverUrl]);
};

export const fetchStatusByIds = async (serverUrl: string, userIds: string[], fetchOnly = false) => {
    let client: Client;
    try {
        client = NetworkManager.getClient(serverUrl);
    } catch (error) {
        return {error};
    }
    if (!userIds.length) {
        return {statuses: []};
    }

    try {
        const statuses = await client.getStatusesByIds(userIds);

        if (!fetchOnly && DatabaseManager.serverDatabases[serverUrl]) {
            const {database, operator} = DatabaseManager.serverDatabases[serverUrl];
            if (operator) {
                const users = await database.get(Database.MM_TABLES.SERVER.USER).query(Q.where('id', Q.oneOf(userIds))).fetch() as UserModel[];
                for (const user of users) {
                    const status = statuses.find((s) => s.user_id === user.id);
                    user.prepareStatus(status?.status || General.OFFLINE);
                }

                await operator.batchRecords(users);
            }
        }

        return {statuses};
    } catch (error) {
        forceLogoutIfNecessary(serverUrl, error as ClientError);
        return {error};
    }
};

export const fetchUsersByIds = async (serverUrl: string, userIds: string[], fetchOnly = false) => {
    let client: Client;
    try {
        client = NetworkManager.getClient(serverUrl);
    } catch (error) {
        return {error};
    }
    if (!userIds.length) {
        return {users: []};
    }

    const operator = DatabaseManager.serverDatabases[serverUrl]?.operator;
    if (!operator) {
        return {error: `${serverUrl} database not found`};
    }

    try {
        const currentUserId = await queryCurrentUserId(operator.database);
        const exisingUsers = await queryUsersById(operator.database, userIds);
        const usersToLoad = userIds.filter((id) => (id !== currentUserId && !exisingUsers.find((u) => u.id === id)));
        const users = await client.getProfilesByIds([...new Set(usersToLoad)]);
        if (!fetchOnly) {
            await operator.handleUsers({
                users,
                prepareRecordsOnly: false,
            });
        }

        return {users};
    } catch (error) {
        forceLogoutIfNecessary(serverUrl, error as ClientError);
        return {error};
    }
};

export const fetchUsersByUsernames = async (serverUrl: string, usernames: string[], fetchOnly = false) => {
    let client: Client;
    try {
        client = NetworkManager.getClient(serverUrl);
    } catch (error) {
        return {error};
    }
    if (!usernames.length) {
        return {users: []};
    }

    const operator = DatabaseManager.serverDatabases[serverUrl]?.operator;
    if (!operator) {
        return {error: `${serverUrl} database not found`};
    }

    try {
        const currentUser = await queryCurrentUser(operator.database);
        const exisingUsers = await queryUsersByUsername(operator.database, usernames);
        const usersToLoad = usernames.filter((username) => (username !== currentUser?.username && !exisingUsers.find((u) => u.username === username)));
        const users = await client.getProfilesByUsernames([...new Set(usersToLoad)]);

        if (!fetchOnly) {
            await operator.handleUsers({
                users,
                prepareRecordsOnly: false,
            });
        }

        return {users};
    } catch (error) {
        forceLogoutIfNecessary(serverUrl, error as ClientError);
        return {error};
    }
};

export const fetchMissingProfilesByIds = async (serverUrl: string, userIds: string[]) => {
    const operator = DatabaseManager.serverDatabases[serverUrl]?.operator;
    if (!operator) {
        return {error: `${serverUrl} database not found`};
    }

    try {
        const {users} = await fetchUsersByIds(serverUrl, userIds);
        if (users) {
            const statusToLoad = users.map((u) => u.id);
            fetchStatusByIds(serverUrl, statusToLoad);
        }
        return {users};
    } catch (error) {
        forceLogoutIfNecessary(serverUrl, error as ClientError);
        return {error};
    }
};

export const fetchMissingProfilesByUsernames = async (serverUrl: string, usernames: string[]) => {
    const operator = DatabaseManager.serverDatabases[serverUrl]?.operator;
    if (!operator) {
        return {error: `${serverUrl} database not found`};
    }

    try {
        const {users} = await fetchUsersByUsernames(serverUrl, usernames);
        if (users) {
            const statusToLoad = users.map((u) => u.id);
            fetchStatusByIds(serverUrl, statusToLoad);
        }
        return {users};
    } catch (error) {
        forceLogoutIfNecessary(serverUrl, error as ClientError);
        return {error};
    }
};

export const updateAllUsersSinceLastDisconnect = async (serverUrl: string) => {
    const database = DatabaseManager.serverDatabases[serverUrl];
    if (!database) {
        return {error: `${serverUrl} database not found`};
    }

    const lastDisconnectedAt = await queryWebSocketLastDisconnected(database.database);

    if (!lastDisconnectedAt) {
        return {users: []};
    }
    const currentUserId = await queryCurrentUserId(database.database);
    const users = await queryAllUsers(database.database);
    const userIds = users.map((u) => u.id).filter((id) => id !== currentUserId);
    let userUpdates: UserProfile[] = [];
    try {
        userUpdates = await NetworkManager.getClient(serverUrl).getProfilesByIds(userIds, {since: lastDisconnectedAt});
    } catch {
        // Do nothing
    }

    if (userUpdates.length) {
        database.operator.handleUsers({users: userUpdates, prepareRecordsOnly: false});
    }

    return {users: userUpdates};
};

export const updateUsersNoLongerVisible = async (serverUrl: string): Promise<{error?: unknown}> => {
    let client: Client;
    try {
        client = NetworkManager.getClient(serverUrl);
    } catch (error) {
        return {error};
    }

    const serverDatabase = DatabaseManager.serverDatabases[serverUrl];
    if (!serverDatabase) {
        return {error: `${serverUrl} database not found`};
    }

    try {
        const knownUsers = new Set(await client.getKnownUsers());
        const currentUserId = await queryCurrentUserId(serverDatabase.database);
        knownUsers.add(currentUserId);

        const models: Model[] = [];
        const allUsers = await queryAllUsers(serverDatabase.database);
        for (const user of allUsers) {
            if (!knownUsers.has(user.id)) {
                user.prepareDestroyPermanently();
                models.push(user);
            }
        }
        if (models.length) {
            serverDatabase.operator.batchRecords(models);
        }
    } catch (error) {
        forceLogoutIfNecessary(serverUrl, error as ClientError);
        return {error};
    }

    return {};
};
export const setStatus = async (serverUrl: string, status: UserStatus) => {
    let client: Client;
    try {
        client = NetworkManager.getClient(serverUrl);
    } catch (error) {
        return {error};
    }

    try {
        const data = await client.updateStatus(status);
        updateUserPresence(serverUrl, status);

        return {
            data,
        };
    } catch (error: any) {
        forceLogoutIfNecessary(serverUrl, error);
        return {error};
    }
};

export const updateCustomStatus = async (serverUrl: string, user: UserModel, customStatus: UserCustomStatus) => {
    let client: Client;
    try {
        client = NetworkManager.getClient(serverUrl);
    } catch (error) {
        return {error};
    }

    try {
        await client.updateCustomStatus(customStatus);
        return {data: true};
    } catch (error) {
        return {error};
    }
};

export const removeRecentCustomStatus = async (serverUrl: string, customStatus: UserCustomStatus) => {
    let client: Client;
    try {
        client = NetworkManager.getClient(serverUrl);
    } catch (error) {
        return {error};
    }

    const operator = DatabaseManager.serverDatabases[serverUrl]?.operator;
    if (!operator) {
        return {error: `${serverUrl} database not found`};
    }

    updateRecentCustomStatuses(serverUrl, customStatus, false, true);

    try {
        await client.removeRecentCustomStatus(customStatus);
    } catch (error) {
        return {error};
    }

    return {data: true};
};

export const unsetCustomStatus = async (serverUrl: string) => {
    let client: Client;

    try {
        client = NetworkManager.getClient(serverUrl);
    } catch (error) {
        return {error};
    }

    try {
        await client.unsetCustomStatus();
    } catch (error) {
        return {error};
    }

    return {data: true};
};