server {
    listen 80;
    server_name _;
    root /usr/share/nginx/html;
    index index.html;

    location / {
        try_files $uri $uri/ /index.html;
    }

    # WebSocket feed. Kept in its own block so the upgrade headers are only set
    # here, and so the API token is injected server-side on the handshake (the
    # browser cannot set headers on a WebSocket).
    location /api/ws {
        proxy_pass http://backend:8000;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_read_timeout 3600s;
        proxy_send_timeout 3600s;
        proxy_set_header ${API_TOKEN_HEADER} "${API_TOKEN}";
    }

    location /api/ {
        proxy_pass http://backend:8000;
        proxy_http_version 1.1;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_read_timeout 3600s;
        # Inject the optional API token server-side so the browser never sees it
        # and the WebUI keeps working without any client changes.
        proxy_set_header ${API_TOKEN_HEADER} "${API_TOKEN}";
    }
}