events {
    worker_connections 1024;
}

http {
    upstream backend_nodes {
        # Round-robin load balancing across all backend nodes
        server backend-node-1:8000 weight=1;
        server backend-node-2:8000 weight=1;
        server backend-node-3:8000 weight=1;
    }

    server {
        listen 8000;
        server_name localhost;

        # Health check endpoint (direct response)
        location /health {
            access_log off;
            return 200 "healthy\n";
            add_header Content-Type text/plain;
        }

        # Proxy all other requests to backend nodes
        location / {
            proxy_pass http://backend_nodes;
            proxy_http_version 1.1;

            # Header handling
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_set_header X-Forwarded-Proto $scheme;

            # Connection settings
            proxy_set_header Connection "";
            proxy_connect_timeout 30s;
            proxy_send_timeout 30s;
            proxy_read_timeout 30s;

            # Buffering
            proxy_buffering on;
            proxy_buffer_size 4k;
            proxy_buffers 8 4k;
        }

        # API documentation
        location /docs {
            proxy_pass http://backend_nodes;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
        }

        location /openapi.json {
            proxy_pass http://backend_nodes;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
        }
    }
}