worker_processes auto;

events {
  worker_connections 1024;
}

http {
  include       /etc/nginx/mime.types;
  default_type  application/octet-stream;

  sendfile        on;
  keepalive_timeout  65;

  map $http_upgrade $connection_upgrade {
    default upgrade;
    ''      close;
  }

  upstream frontend {
    server 127.0.0.1:${FRONTEND_PORT};
  }

  upstream backend {
    server 127.0.0.1:${BACKEND_PORT};
  }

  server {
    listen ${PORT};

    # Proxy WebSocket traffic for Socket.IO to the NestJS backend
    location /socket.io/ {
      proxy_pass http://backend;
      proxy_http_version 1.1;
      proxy_set_header Upgrade $http_upgrade;
      proxy_set_header Connection $connection_upgrade;
      proxy_set_header Host $host;
      proxy_cache_bypass $http_upgrade;
    }

    # Proxy all other traffic to Next.js frontend (which rewrites /api to backend)
    location / {
      proxy_pass http://frontend;
      proxy_http_version 1.1;
      proxy_set_header Upgrade $http_upgrade;
      proxy_set_header Connection $connection_upgrade;
      proxy_set_header Host $host;
      proxy_set_header X-Real-IP $remote_addr;
      proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    }
  }
}