server {
    listen 80 default_server;
    listen [::]:80 default_server;

    # Root directory for static files.
    # This should match the directory where Astro's build output (e.g., from 'dist')
    # is copied in your Dockerfile (e.g., COPY --from=builder /app/dist /usr/share/nginx/html).
    root /usr/share/nginx/html;
    index index.html index.htm;

    # Serve Astro static site
    location / {
        try_files $uri $uri/ /index.html =404;
    }

    # Proxy API requests to the Node.js backend server.
    # The Node.js server is expected to be running on localhost:3000 inside the container.
    location /api/ { # Note the trailing slash here
        proxy_pass http://localhost:3000/api/; # And here. This ensures /api/foo becomes http://localhost:3000/api/foo

        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection 'upgrade'; # Important for WebSocket, etc.
        proxy_set_header Host $host; # Preserves the original host header
        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;
        proxy_cache_bypass $http_upgrade; # Useful for avoiding caching issues during development or for dynamic content
    }

    # Optional: Custom error pages
    error_page 500 502 503 504 /50x.html;
    location = /50x.html {
        # Ensure you have a 50x.html file in your static assets root
        root /usr/share/nginx/html;
    }
}