SerpentRace/SerpentRace_Backend/src/Application/Game/commands/JoinGameCommandHandler.ts

import { JoinGameCommand } from './JoinGameCommand';
import { GameAggregate, GameState, LoginType } from '../../../Domain/Game/GameAggregate';
import { IGameRepository } from '../../../Domain/IRepository/IGameRepository';
import { DIContainer } from '../../Services/DIContainer';
import { RedisService } from '../../Services/RedisService';
import { logOther, logError } from '../../Services/Logger';
import { v4 as uuidv4 } from 'uuid';

export interface GamePlayerData {
    playerId: string;
    playerName?: string;
    joinedAt: Date;
    isOnline: boolean;
    position?: number;  // For game board position (to be used later)
}

export interface ActiveGameData {
    gameId: string;
    gameCode: string;
    hostId?: string;
    maxPlayers: number;
    currentPlayers: GamePlayerData[];
    state: GameState;
    createdAt: Date;
    startedAt?: Date;
    currentTurn?: string;  // Player ID whose turn it is
    websocketRoom: string;  // WebSocket room name for real-time updates
}

export class JoinGameCommandHandler {
    private gameRepository: IGameRepository;
    private redisService: RedisService;

    constructor() {
        this.gameRepository = DIContainer.getInstance().gameRepository;
        this.redisService = RedisService.getInstance();
    }

    async handle(command: JoinGameCommand): Promise<GameAggregate> {
        const startTime = performance.now();
        
        try {
            logOther('Joining game', `gameCode: ${command.gameCode}, playerId: ${command.playerId || 'anonymous'}, loginType: ${command.loginType}`);

            // Find the game by game code
            const game = await this.gameRepository.findByGameCode(command.gameCode);
            if (!game) {
                throw new Error(`Game with code ${command.gameCode} not found`);
            }

            // Generate player ID for public games or use provided one
            const actualPlayerId = command.playerId || uuidv4();

            // Validate game joinability (authentication/org checks done in router)
            this.validateGameJoinability(game, actualPlayerId, command);

            // Add player to database
            const updatedGame = await this.gameRepository.addPlayerToGame(game.id, actualPlayerId);
            if (!updatedGame) {
                throw new Error('Failed to add player to game');
            }

            // Update Redis with the new player
            await this.updateGameInRedis(updatedGame, { ...command, playerId: actualPlayerId });

            const endTime = performance.now();
            logOther('Player joined game successfully', {
                gameId: game.id,
                gameCode: game.gamecode,
                playerId: actualPlayerId,
                playerCount: updatedGame.players.length,
                maxPlayers: updatedGame.maxplayers,
                loginType: game.logintype,
                executionTime: Math.round(endTime - startTime)
            });

            return updatedGame;

        } catch (error) {
            const endTime = performance.now();
            logError('Failed to join game', error instanceof Error ? error : new Error(String(error)));
            logOther('Game join failed', {
                gameCode: command.gameCode,
                playerId: command.playerId || 'anonymous',
                loginType: command.loginType,
                executionTime: Math.round(endTime - startTime)
            });
            throw error;
        }
    }

    private validateGameJoinability(game: GameAggregate, playerId: string, command: JoinGameCommand): void {
        // Check if game is in waiting state
        if (game.state !== GameState.WAITING) {
            throw new Error('Game is not accepting new players');
        }

        // Check if player is already in the game
        if (game.players.includes(playerId)) {
            throw new Error('Player is already in this game');
        }

        // Check if game is full
        if (game.players.length >= game.maxplayers) {
            throw new Error('Game is full');
        }

        // Note: Login type validation is now handled in the router before reaching this handler
        // This ensures proper authentication and organization membership checks are done first

        logOther('Game join validation passed', {
            gameId: game.id,
            gameCode: game.gamecode,
            currentPlayers: game.players.length,
            maxPlayers: game.maxplayers,
            gameState: game.state,
            loginType: game.logintype,
            playerId: playerId,
            isAuthenticated: !!command.playerId
        });
    }

    private async updateGameInRedis(game: GameAggregate, command: JoinGameCommand & { playerId: string }): Promise<void> {
        try {
            const redisKey = `game:${game.id}`;
            
            // Get existing game data from Redis or create new
            let gameData: ActiveGameData;
            const existingData = await this.redisService.get(redisKey);
            
            if (existingData) {
                gameData = JSON.parse(existingData) as ActiveGameData;
            } else {
                // Create new game data structure
                gameData = {
                    gameId: game.id,
                    gameCode: game.gamecode,
                    maxPlayers: game.maxplayers,
                    currentPlayers: [],
                    state: game.state,
                    createdAt: game.createdate,
                    websocketRoom: `game_${game.gamecode}`
                };
            }

            // Add the new player
            const newPlayer: GamePlayerData = {
                playerId: command.playerId,
                playerName: command.playerName,
                joinedAt: new Date(),
                isOnline: true
            };

            // Check if player name is already in use by a different player
            const existingPlayerWithName = gameData.currentPlayers.find(
                p => p.playerName === command.playerName && p.playerId !== command.playerId
            );

            if (existingPlayerWithName) {
                throw new Error(`Player name "${command.playerName}" is already in use in this game`);
            }

            // Update players list (remove if exists, then add)
            gameData.currentPlayers = gameData.currentPlayers.filter(p => p.playerId !== command.playerId);
            gameData.currentPlayers.push(newPlayer);

            // Update game state and player count
            gameData.state = game.state;

            // Store updated data in Redis with TTL (24 hours)
            await this.redisService.setWithExpiry(redisKey, JSON.stringify(gameData), 24 * 60 * 60);

            logOther('Game data updated in Redis', {
                gameId: game.id,
                gameCode: game.gamecode,
                redisKey,
                playerCount: gameData.currentPlayers.length,
                websocketRoom: gameData.websocketRoom,
                playerId: command.playerId
            });

        } catch (error) {
            logError('Failed to update game in Redis', error instanceof Error ? error : new Error(String(error)));
            // Don't throw error here - Redis failure shouldn't prevent game join
            logOther('Game join completed despite Redis error', {
                gameId: game.id,
                playerId: command.playerId
            });
        }
    }

    async getGameFromRedis(gameId: string): Promise<ActiveGameData | null> {
        try {
            const redisKey = `game:${gameId}`;
            const data = await this.redisService.get(redisKey);
            return data ? JSON.parse(data) as ActiveGameData : null;
        } catch (error) {
            logError('Failed to get game from Redis', error instanceof Error ? error : new Error(String(error)));
            return null;
        }
    }

    async removePlayerFromRedis(gameId: string, playerId: string): Promise<void> {
        try {
            const redisKey = `game:${gameId}`;
            const existingData = await this.redisService.get(redisKey);
            
            if (existingData) {
                const gameData = JSON.parse(existingData) as ActiveGameData;
                gameData.currentPlayers = gameData.currentPlayers.filter(p => p.playerId !== playerId);
                
                await this.redisService.setWithExpiry(redisKey, JSON.stringify(gameData), 24 * 60 * 60);
            }
        } catch (error) {
            logError('Failed to remove player from Redis', error instanceof Error ? error : new Error(String(error)));
        }
    }
}