CatchTheLettersBackend/src/main/java/com/example/catchTheLetters/service/impl/RoomServiceImpl.java

package com.example.catchTheLetters.service.impl;

import com.example.catchTheLetters.entity.*;
import com.example.catchTheLetters.enums.MessageType;
import com.example.catchTheLetters.enums.RoomStatus;
import com.example.catchTheLetters.model.vo.Letter;
import com.example.catchTheLetters.service.AuthService;
import com.example.catchTheLetters.service.RoomService;
import com.fasterxml.jackson.databind.ObjectMapper;
import jakarta.annotation.Resource;
import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.stereotype.Service;
import org.springframework.web.socket.TextMessage;
import org.springframework.web.socket.WebSocketSession;

import java.io.IOException;
import java.util.Map;
import java.util.Random;
import java.util.concurrent.ConcurrentHashMap;

@Service
public class RoomServiceImpl implements RoomService {

    // 房间列表
    private final ConcurrentHashMap<Long, GameRoom> rooms = new ConcurrentHashMap<>();

    private final ObjectMapper objectMapper = new ObjectMapper();

    private final Random random = new Random();

    @Resource
    private MongoTemplate mongoTemplate;

    @Resource
    private AuthService authService;

    @Override
    public void addPlayer(long roomId, WebSocketSession session, String token) {
        var room = rooms.get(roomId);
        var players = room.getPlayers();
        var user = authService.verify(token);
        var player = new PlayerInGame(user.getId(), user);

        // 如果玩家已经在房间中，更新他们的WebSocketSession
        for (var entry : players.entrySet()) {
            if (entry.getValue().getUserId().equals(user.getId())) {
                player = entry.getValue();
                players.remove(entry.getKey());
                break;
            }
        }
        players.put(session, player);

        // TODO 发送消息通知其他玩家有人加入了
    }

    @Override
    public void removePlayer(long roomId, WebSocketSession session) {
        var room = rooms.get(roomId);
        var players = room.getPlayers();
        players.remove(session);
        // 如果是房主退出，更换房主，否则关闭房间
        if (session == room.getHost()) {
            if (!players.isEmpty()) {
                room.setHost(players.keySet().iterator().next());
            } else {
                rooms.remove(roomId);
            }
        }
        // TODO 发送消息通知其他玩家有人退出了
    }

    @Override
    public void startGame(long roomId, WebSocketSession session) {
        var room = rooms.get(roomId);
        var players = room.getPlayers();
        var readyPlayers = room.getReadyPlayers();
        readyPlayers.add(session);
        // TODO 发送消息通知其他玩家有人准备好了
        // 如果所有玩家都准备好了，开始游戏
        if (readyPlayers.size() == room.getPlayers().size()) {
            // TODO 发送消息通知所有玩家游戏开始
            readyPlayers.clear();
            room.setStatus(RoomStatus.PLAYING);
            gameLogic(room);
        }
    }

    @Override
    public void cancelStartGame(long roomId, WebSocketSession session) {
        var room = rooms.get(roomId);
        var readyPlayers = room.getReadyPlayers();
        readyPlayers.remove(session);
        // TODO 发送消息通知其他玩家有人取消准备
    }

    @Override
    public void endGame(long roomId) {
        var room = rooms.get(roomId);
        room.setStatus(RoomStatus.WAITING);
        // TODO 发送消息通知所有玩家游戏结束
    }

    @Override
    public void handleInput(long roomId, WebSocketSession session, PlayerInput input) {
        var message = new GameMessage<>(MessageType.INPUT, input);
        var room = rooms.get(roomId);
        var players = room.getPlayers();
        for (var player : players.keySet())
            if (player != session) sendMessage(player, message);
    }

    @Override
    public void createRoom(WebSocketSession session, String token) {
        var user = authService.verify(token);
        var player = new PlayerInGame(user.getId(), user);
        var room = new GameRoom(session, player);
        rooms.put(room.getRoomId(), room);
    }

    @Override
    public void removeRoom(long roomId) {
        // 如果房间内还有玩家，全部移除
        var room = rooms.get(roomId);
        var players = room.getPlayers();
        for (var player : players.keySet()) {
            // TODO 发送消息通知所有玩家房间已解散
        }
        rooms.remove(roomId);
    }

    private void generateLetter(GameRoom room) {
        var players = room.getPlayers();
        var words = room.getWords();

        // 如果words长度<=5，从数据库中再获取一批随机单词
        if (words.size() <= 5) getWords(words);

        Letter letter;

        var val = random.nextInt(100);

        // 在80%概率当前单词的字母中随机选择一个，19%随机生成一个字母，1%是回血爱心。选定后随机赋值2f到6f的下落速度
        if (val == 0)
            // 回血爱心
            letter = new Letter("10", random.nextFloat(1), random.nextFloat(2, 6));
        if (val >= 1 && val <= 81)
            // 从当前单词中随机选择一个字母
            letter = new Letter(words.keySet().toArray()[random.nextInt(words.size())].toString(), random.nextFloat(1), random.nextFloat(2, 6));
        else
            // 随机生成一个字母
            letter = new Letter(String.valueOf((char) (random.nextInt(26) + 'a')), random.nextFloat(1), random.nextFloat(2, 6));

        // 给所有玩家发送字母
        for (var player : players.keySet())
            sendMessage(player, new GameMessage<>(MessageType.LETTER, letter));
    }

    private <T> void sendMessage(WebSocketSession session, T message) {
        String json;
        if (!(message instanceof String)) {
            try {
                json = objectMapper.writeValueAsString(message);
            } catch (Exception e) {
                throw new RuntimeException("消息转为JSON字符串操作失败", e);
            }
        } else json = (String) message;
        try {
            session.sendMessage(new TextMessage(json));
        } catch (IOException e) {
            throw new RuntimeException("发送消息失败", e);
        }
    }

    private void getWords(Map<String, Integer> words) {
        // TODO 从数据库中获取一批随机单词，然后放入words中，并把单词数组推送给所有玩家
    }

    private void gameLogic(GameRoom room) {
        getWords(room.getWords());
        // TODO 从300秒开始倒计时，每秒调用一次generateLetter方法，如果时间到了，调用endGame方法，如果当前单词被某玩家拼完，Map对应单词的value++，如果value>=玩家数（有可能中途有人退出），目前单词出队列，继续下一个单词
    }
}