package emu.grasscutter.database;

import java.util.List;
import java.util.stream.Stream;

import com.mongodb.client.result.DeleteResult;

import dev.morphia.query.FindOptions;
import dev.morphia.query.Sort;
import dev.morphia.query.experimental.filters.Filters;
import emu.grasscutter.GameConstants;
import emu.grasscutter.Grasscutter;
import emu.grasscutter.game.Account;
import emu.grasscutter.game.activity.PlayerActivityData;
import emu.grasscutter.game.activity.musicgame.MusicGameBeatmap;
import emu.grasscutter.game.avatar.Avatar;
import emu.grasscutter.game.battlepass.BattlePassManager;
import emu.grasscutter.game.friends.Friendship;
import emu.grasscutter.game.gacha.GachaRecord;
import emu.grasscutter.game.home.GameHome;
import emu.grasscutter.game.inventory.GameItem;
import emu.grasscutter.game.mail.Mail;
import emu.grasscutter.game.player.Player;
import emu.grasscutter.game.quest.GameMainQuest;

import static com.mongodb.client.model.Filters.eq;

public final class DatabaseHelper {
    public static Account createAccount(String username) {
        return createAccountWithUid(username, 0);
    }

    public static Account createAccountWithUid(String username, int reservedUid) {
        // Unique names only
        if (DatabaseHelper.checkIfAccountExists(username)) {
            return null;
        }

        // Make sure there are no id collisions
        if (reservedUid > 0) {
            // Cannot make account with the same uid as the server console
            if (reservedUid == GameConstants.SERVER_CONSOLE_UID) {
                return null;
            }

            if (DatabaseHelper.checkIfAccountExists(reservedUid)) {
                return null;
            }

            // Make sure no existing player already has this id.
            if (DatabaseHelper.checkIfPlayerExists(reservedUid)) {
                return null;
            }
        }

        // Account
        Account account = new Account();
        account.setUsername(username);
        account.setId(Integer.toString(DatabaseManager.getNextId(account)));

        if (reservedUid > 0) {
            account.setReservedPlayerUid(reservedUid);
        }

        DatabaseHelper.saveAccount(account);
        return account;
    }

    @Deprecated
    public static Account createAccountWithPassword(String username, String password) {
        // Unique names only
        Account exists = DatabaseHelper.getAccountByName(username);
        if (exists != null) {
            return null;
        }

        // Account
        Account account = new Account();
        account.setId(Integer.toString(DatabaseManager.getNextId(account)));
        account.setUsername(username);
        account.setPassword(password);
        DatabaseHelper.saveAccount(account);
        return account;
    }

    public static void saveAccount(Account account) {
        DatabaseManager.getAccountDatastore().save(account);
    }

    public static Account getAccountByName(String username) {
        return DatabaseManager.getAccountDatastore().find(Account.class).filter(Filters.eq("username", username)).first();
    }

    public static Account getAccountByToken(String token) {
        if (token == null) return null;
        return DatabaseManager.getAccountDatastore().find(Account.class).filter(Filters.eq("token", token)).first();
    }

    public static Account getAccountBySessionKey(String sessionKey) {
        if (sessionKey == null) return null;
        return DatabaseManager.getAccountDatastore().find(Account.class).filter(Filters.eq("sessionKey", sessionKey)).first();
    }

    public static Account getAccountById(String uid) {
        return DatabaseManager.getAccountDatastore().find(Account.class).filter(Filters.eq("_id", uid)).first();
    }

    public static Account getAccountByPlayerId(int playerId) {
        return DatabaseManager.getAccountDatastore().find(Account.class).filter(Filters.eq("reservedPlayerId", playerId)).first();
    }

    public static boolean checkIfAccountExists(String name) {
        return DatabaseManager.getAccountDatastore().find(Account.class).filter(Filters.eq("username", name)).count() > 0;
    }

    public static boolean checkIfAccountExists(int reservedUid) {
        return DatabaseManager.getAccountDatastore().find(Account.class).filter(Filters.eq("reservedPlayerId", reservedUid)).count() > 0;
    }

    public static synchronized void deleteAccount(Account target) {
        // To delete an account, we need to also delete all the other documents in the database that reference the account.
        // This should optimally be wrapped inside a transaction, to make sure an error thrown mid-way does not leave the
        // database in an inconsistent state, but unfortunately Mongo only supports that when we have a replica set ...

        Player player = Grasscutter.getGameServer().getPlayerByAccountId(target.getId());

        // Close session first
        if (player != null) {
            player.getSession().close();
        } else {
            player = getPlayerByAccount(target);
            if (player == null) return;
        }
        int uid = player.getUid();
        // Delete data from collections
        DatabaseManager.getGameDatabase().getCollection("activities").deleteMany(eq("uid", uid));
        DatabaseManager.getGameDatabase().getCollection("homes").deleteMany(eq("ownerUid", uid));
        DatabaseManager.getGameDatabase().getCollection("mail").deleteMany(eq("ownerUid", uid));
        DatabaseManager.getGameDatabase().getCollection("avatars").deleteMany(eq("ownerId", uid));
        DatabaseManager.getGameDatabase().getCollection("gachas").deleteMany(eq("ownerId", uid));
        DatabaseManager.getGameDatabase().getCollection("items").deleteMany(eq("ownerId", uid));
        DatabaseManager.getGameDatabase().getCollection("quests").deleteMany(eq("ownerUid", uid));
        DatabaseManager.getGameDatabase().getCollection("battlepass").deleteMany(eq("ownerUid", uid));

        // Delete friendships.
        // Here, we need to make sure to not only delete the deleted account's friendships,
        // but also all friendship entries for that account's friends.
        DatabaseManager.getGameDatabase().getCollection("friendships").deleteMany(eq("ownerId", uid));
        DatabaseManager.getGameDatabase().getCollection("friendships").deleteMany(eq("friendId", uid));

        // Delete the player last.
        DatabaseManager.getGameDatastore().find(Player.class).filter(Filters.eq("id", uid)).delete();

        // Finally, delete the account itself.
        DatabaseManager.getAccountDatastore().find(Account.class).filter(Filters.eq("id", target.getId())).delete();
    }

    public static <T> Stream<T> getByGameClass(Class<T> classType) {
        return DatabaseManager.getGameDatastore().find(classType).stream();
    }

    @Deprecated(forRemoval = true)
    public static List<Player> getAllPlayers() {
        return DatabaseManager.getGameDatastore().find(Player.class).stream().toList();
    }

    public static Player getPlayerByUid(int id) {
        return DatabaseManager.getGameDatastore().find(Player.class).filter(Filters.eq("_id", id)).first();
    }

    @Deprecated
    public static Player getPlayerByAccount(Account account) {
        return DatabaseManager.getGameDatastore().find(Player.class).filter(Filters.eq("accountId", account.getId())).first();
    }

    public static Player getPlayerByAccount(Account account, Class<? extends Player> playerClass) {
        return DatabaseManager.getGameDatastore().find(playerClass).filter(Filters.eq("accountId", account.getId())).first();
    }

    public static boolean checkIfPlayerExists(int uid) {
        return DatabaseManager.getGameDatastore().find(Player.class).filter(Filters.eq("_id", uid)).count() > 0;
    }

    public static synchronized Player generatePlayerUid(Player character, int reservedId) {
        // Check if reserved id
        int id;
        if (reservedId > 0 && !checkIfPlayerExists(reservedId)) {
            id = reservedId;
            character.setUid(id);
        } else {
            do {
                id = DatabaseManager.getNextId(character);
            }
            while (checkIfPlayerExists(id));
            character.setUid(id);
        }
        // Save to database
        DatabaseManager.getGameDatastore().save(character);
        return character;
    }

    public static synchronized int getNextPlayerId(int reservedId) {
        // Check if reserved id
        int id;
        if (reservedId > 0 && !checkIfPlayerExists(reservedId)) {
            id = reservedId;
        } else {
            do {
                id = DatabaseManager.getNextId(Player.class);
            }
            while (checkIfPlayerExists(id));
        }
        return id;
    }

    public static void savePlayer(Player character) {
        DatabaseManager.getGameDatastore().save(character);
    }

    public static void saveAvatar(Avatar avatar) {
        DatabaseManager.getGameDatastore().save(avatar);
    }

    public static List<Avatar> getAvatars(Player player) {
        return DatabaseManager.getGameDatastore().find(Avatar.class).filter(Filters.eq("ownerId", player.getUid())).stream().toList();
    }

    public static void saveItem(GameItem item) {
        DatabaseManager.getGameDatastore().save(item);
    }

    public static boolean deleteItem(GameItem item) {
        DeleteResult result = DatabaseManager.getGameDatastore().delete(item);
        return result.wasAcknowledged();
    }

    public static List<GameItem> getInventoryItems(Player player) {
        return DatabaseManager.getGameDatastore().find(GameItem.class).filter(Filters.eq("ownerId", player.getUid())).stream().toList();
    }

    public static List<Friendship> getFriends(Player player) {
        return DatabaseManager.getGameDatastore().find(Friendship.class).filter(Filters.eq("ownerId", player.getUid())).stream().toList();
    }

    public static List<Friendship> getReverseFriends(Player player) {
        return DatabaseManager.getGameDatastore().find(Friendship.class).filter(Filters.eq("friendId", player.getUid())).stream().toList();
    }

    public static void saveFriendship(Friendship friendship) {
        DatabaseManager.getGameDatastore().save(friendship);
    }

    public static void deleteFriendship(Friendship friendship) {
        DatabaseManager.getGameDatastore().delete(friendship);
    }

    public static Friendship getReverseFriendship(Friendship friendship) {
        return DatabaseManager.getGameDatastore().find(Friendship.class).filter(Filters.and(
                Filters.eq("ownerId", friendship.getFriendId()),
                Filters.eq("friendId", friendship.getOwnerId())
        )).first();
    }

    public static List<GachaRecord> getGachaRecords(int ownerId, int page, int gachaType) {
        return getGachaRecords(ownerId, page, gachaType, 10);
    }

    public static List<GachaRecord> getGachaRecords(int ownerId, int page, int gachaType, int pageSize) {
        return DatabaseManager.getGameDatastore().find(GachaRecord.class).filter(
            Filters.eq("ownerId", ownerId),
            Filters.eq("gachaType", gachaType)
        ).iterator(new FindOptions()
                .sort(Sort.descending("transactionDate"))
                .skip(pageSize * page)
                .limit(pageSize)
        ).toList();
    }

    public static long getGachaRecordsMaxPage(int ownerId, int page, int gachaType) {
        return getGachaRecordsMaxPage(ownerId, page, gachaType, 10);
    }

    public static long getGachaRecordsMaxPage(int ownerId, int page, int gachaType, int pageSize) {
        long count = DatabaseManager.getGameDatastore().find(GachaRecord.class).filter(
            Filters.eq("ownerId", ownerId),
            Filters.eq("gachaType", gachaType)
        ).count();
        return count / 10 + (count % 10 > 0 ? 1 : 0 );
    }

    public static void saveGachaRecord(GachaRecord gachaRecord) {
        DatabaseManager.getGameDatastore().save(gachaRecord);
    }

    public static List<Mail> getAllMail(Player player) {
        return DatabaseManager.getGameDatastore().find(Mail.class).filter(Filters.eq("ownerUid", player.getUid())).stream().toList();
    }

    public static void saveMail(Mail mail) {
        DatabaseManager.getGameDatastore().save(mail);
    }

    public static boolean deleteMail(Mail mail) {
        DeleteResult result = DatabaseManager.getGameDatastore().delete(mail);
        return result.wasAcknowledged();
    }

    public static List<GameMainQuest> getAllQuests(Player player) {
        return DatabaseManager.getGameDatastore().find(GameMainQuest.class).filter(Filters.eq("ownerUid", player.getUid())).stream().toList();
    }

    public static void saveQuest(GameMainQuest quest) {
        DatabaseManager.getGameDatastore().save(quest);
    }

    public static boolean deleteQuest(GameMainQuest quest) {
        return DatabaseManager.getGameDatastore().delete(quest).wasAcknowledged();
    }

    public static GameHome getHomeByUid(int id) {
        return DatabaseManager.getGameDatastore().find(GameHome.class).filter(Filters.eq("ownerUid", id)).first();
    }

    public static void saveHome(GameHome gameHome) {
        DatabaseManager.getGameDatastore().save(gameHome);
    }

    public static BattlePassManager loadBattlePass(Player player) {
        BattlePassManager manager = DatabaseManager.getGameDatastore().find(BattlePassManager.class).filter(Filters.eq("ownerUid", player.getUid())).first();
        if (manager == null) {
            manager = new BattlePassManager(player);
            manager.save();
        } else {
            manager.setPlayer(player);
        }
        return manager;
    }

    public static void saveBattlePass(BattlePassManager manager) {
        DatabaseManager.getGameDatastore().save(manager);
    }

    public static PlayerActivityData getPlayerActivityData(int uid, int activityId) {
        return DatabaseManager.getGameDatastore().find(PlayerActivityData.class)
            .filter(Filters.and(Filters.eq("uid", uid),Filters.eq("activityId", activityId)))
            .first();
    }

    public static void savePlayerActivityData(PlayerActivityData playerActivityData) {
        DatabaseManager.getGameDatastore().save(playerActivityData);
    }

    public static MusicGameBeatmap getMusicGameBeatmap(long musicShareId) {
        return DatabaseManager.getGameDatastore().find(MusicGameBeatmap.class)
            .filter(Filters.eq("musicShareId", musicShareId))
            .first();
    }

    public static void saveMusicGameBeatmap(MusicGameBeatmap musicGameBeatmap) {
        DatabaseManager.getGameDatastore().save(musicGameBeatmap);
    }
}
