server {
    listen 80;
    server_name localhost;
    root /usr/share/nginx/html;

    # Gzip compression
    gzip on;
    gzip_types text/plain text/css application/json application/javascript text/xml application/xml;

    # SvelteKit SPA routing
    location / {
        try_files $uri $uri/ /index.html;
    }

    # API proxy to backend
    location /api/ {
        proxy_pass http://backend:8080;
        proxy_http_version 1.1;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

        # SSE specific settings - critical for streaming
        proxy_set_header X-Accel-Buffering no;
        proxy_buffering off;
        proxy_cache off;
        chunked_transfer_encoding off;
        proxy_read_timeout 86400s;
        proxy_send_timeout 86400s;

        # Keep connection open for SSE
        proxy_set_header Connection '';
    }

    # Health check
    location /health {
        proxy_pass http://backend:8080;
    }

    # Prometheus metrics endpoint
    location /metrics {
        proxy_pass http://backend:8080;
    }

    # Cache static assets
    location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff|woff2)$ {
        expires 1y;
        add_header Cache-Control "public, immutable";
    }
}