services:
  # 메인 DB
  mysql:
    image: mysql:8.4
    container_name: mysql
    restart: unless-stopped
    # dirty page 디스크 플러시를 위한 대기 시간 확보
    stop_grace_period: 1m
    environment:
      MYSQL_ROOT_PASSWORD: ${MYSQL_ROOT_PASSWORD}
      MYSQL_DATABASE: ${MYSQL_DATABASE}
      MYSQL_USER: ${MYSQL_USER}
      MYSQL_PASSWORD: ${MYSQL_PASSWORD}
      TZ: Asia/Seoul
    # 256MB 환경 구동을 위한 메모리 다이어트 옵션 전달
    command:
      - --innodb-buffer-pool-size=128M
      - --performance-schema=OFF
      - --max-connections=30
      - --character-set-server=utf8mb4
      - --collation-server=utf8mb4_unicode_ci
    volumes:
      - mysql-data:/var/lib/mysql
    deploy:
      resources:
        limits:
          memory: 384M # 256MB 목표이나 구동 시 버퍼 고려해 384MB 하드 리밋
    healthcheck:
      # 포트 오픈 여부가 아닌 실제 쿼리 응답 여부 검증
      test: ["CMD-SHELL", "mysqladmin ping -h localhost -u root -p$${MYSQL_ROOT_PASSWORD}"]
      interval: 10s
      timeout: 5s
      retries: 5
      start_period: 30s
    logging: &default-logging
      driver: "json-file"
      options:
        max-size: "10m"
        max-file: "3"
    networks:
      - backend-net

  # 채팅 DB
  mongodb:
    image: mongo:7.0
    container_name: mongodb
    restart: unless-stopped
    stop_grace_period: 30s
    environment:
      MONGO_INITDB_ROOT_USERNAME: ${MONGO_INITDB_ROOT_USERNAME}
      MONGO_INITDB_ROOT_PASSWORD: ${MONGO_INITDB_ROOT_PASSWORD}
      TZ: Asia/Seoul
    # WiredTiger 캐시를 256MB로 명시적 제한하여 OOM Crash 방지
    command: ["mongod", "--wiredTigerCacheSizeGB", "0.25"]
    volumes:
      - mongo-data:/data/db
    deploy:
      resources:
        limits:
          memory: 512M
    healthcheck:
      test: ["CMD-SHELL", "mongosh --eval 'db.adminCommand(\"ping\")' --quiet"]
      interval: 10s
      timeout: 5s
      retries: 5
      start_period: 20s
    logging: *default-logging
    networks:
      - backend-net

  # 세션 관리 및 응답 캐싱
  redis:
    image: redis:7.2-alpine
    container_name: redis
    restart: unless-stopped
    command: >
      redis-server
      --requirepass ${REDIS_PASSWORD}
      --maxmemory 96mb
      --maxmemory-policy allkeys-lru
    deploy:
      resources:
        limits:
          memory: 128M
    healthcheck:
      test: ["CMD", "redis-cli", "-a", "${REDIS_PASSWORD}", "ping"]
      interval: 5s
      timeout: 3s
      retries: 3
      start_period: 5s
    logging: *default-logging
    networks:
      - backend-net

  # AI 중계 서버
  fastapi:
    image: ${FASTAPI_IMAGE} # GitHub Actions에서 빌드/푸시한 이미지 태그
    container_name: fastapi
    restart: unless-stopped
    environment:
      - OPENAI_API_KEY=${OPENAI_API_KEY}
      - CLAUDE_API_KEY=${CLAUDE_API_KEY}
      - TZ=Asia/Seoul
    deploy:
      resources:
        limits:
          memory: 512M
    healthcheck:
      test: ["CMD-SHELL", "curl -f http://localhost:8000/health || exit 1"]
      interval: 10s
      timeout: 5s
      retries: 3
      start_period: 10s
    logging: *default-logging
    networks:
      - backend-net

  # 핵심 비즈니스 로직 API 서버
  springboot:
    image: ${SPRINGBOOT_IMAGE}
    container_name: springboot
    restart: unless-stopped
    environment:
      - SPRING_PROFILES_ACTIVE=prod
      - SPRING_DATASOURCE_URL=jdbc:mysql://mysql:3306/${MYSQL_DATABASE}?useSSL=false&allowPublicKeyRetrieval=true
      - SPRING_DATASOURCE_USERNAME=${MYSQL_USER}
      - SPRING_DATASOURCE_PASSWORD=${MYSQL_PASSWORD}
      - SPRING_DATA_MONGODB_URI=mongodb://${MONGO_INITDB_ROOT_USERNAME}:${MONGO_INITDB_ROOT_PASSWORD}@mongodb:27017/${MONGO_DATABASE}?authSource=admin
      - SPRING_DATA_REDIS_HOST=redis
      - SPRING_DATA_REDIS_PORT=6379
      - SPRING_DATA_REDIS_PASSWORD=${REDIS_PASSWORD}
      - FASTAPI_BASE_URL=http://fastapi:8000
      - TZ=Asia/Seoul
      # JVM 힙 메모리를 512MB로 제한하고 GC 오버헤드를 줄이기 위한 옵션
      - JAVA_OPTS=-Xms256m -Xmx512m -XX:MaxMetaspaceSize=192m
    depends_on:
      mysql:
        condition: service_healthy # MySQL 핑 응답 확인 후 구동 시작
      mongodb:
        condition: service_healthy
      redis:
        condition: service_healthy
      fastapi:
        condition: service_healthy
    deploy:
      resources:
        limits:
          memory: 1024M
    healthcheck:
      test: ["CMD-SHELL", "curl -f http://localhost:8080/actuator/health || exit 1"]
      interval: 15s
      timeout: 5s
      retries: 5
      start_period: 40s # Spring Boot JVM 부팅 시간을 감안한 유예시간
    logging: *default-logging
    networks:
      - backend-net
      - frontend-net

  # Reverse Proxy & Static Web Server
  nginx:
    image: nginx:alpine
    container_name: nginx
    restart: unless-stopped
    ports:
      - "80:80"
      - "443:443"
    volumes:
      - certbot-certs:/etc/letsencrypt:ro # 발급된 인증서
      - certbot-challenge:/var/www/certbot:ro # Let's Encrypt 검증 파일
    depends_on:
      springboot:
        condition: service_healthy # 백엔드 기동 완료 후 라우팅 오픈
    deploy:
      resources:
        limits:
          memory: 64M
    healthcheck:
      test: ["CMD-SHELL", "wget -q --spider http://localhost/ || exit 1"]
      interval: 10s
      timeout: 3s
      retries: 3
    logging: *default-logging
    networks:
      - frontend-net

  certbot:
    image: certbot/certbot:latest
    container_name: certbot
    profiles: ["tools"] # 상시 구동할 필요가 없기 때문에 명시적으로 호출할 때만 동작
    volumes:
      - certbot-certs:/etc/letsencrypt:rw
      - certbot-challenge:/var/www/certbot:rw

# 네트워크 분리: DB/캐시는 외부에 노출되지 않도록 완전 격리
networks:
  backend-net:
    driver: bridge
  frontend-net:
    driver: bridge

volumes:
  mysql-data:
  mongo-data:
  certbot-certs:
  certbot-challenge: