map $uri $empty {
    default "";
}

server {
    listen 80;
    server_name _;

    client_max_body_size 50M;
    absolute_redirect off;

    # React SPA at root
    location / {
        root /usr/share/nginx/html/app;
        try_files $uri $uri/ /index.html;
        add_header Cache-Control "no-cache, no-store, must-revalidate" always;
        add_header X-Frame-Options "DENY" always;
        add_header X-Content-Type-Options "nosniff" always;
        add_header X-XSS-Protection "1; mode=block" always;
        add_header Referrer-Policy "strict-origin-when-cross-origin" always;
        add_header Permissions-Policy "geolocation=(), microphone=(), camera=()" always;
    }

    # Backend API proxy
    location /api/ {
        proxy_pass http://backend:8000/api/;
        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;
        proxy_read_timeout 900s;
        proxy_send_timeout 900s;
        proxy_connect_timeout 60s;
        add_header X-Frame-Options "DENY" always;
        add_header X-Content-Type-Options "nosniff" always;
    }
}