server {
    listen 80;

    root /usr/share/nginx/html;
    index index.html;

    # API no mesmo domínio: sem CORS e sem URL da API embutido no build.
    location ~ ^/(api|docs|openapi)(/|$) {
        proxy_pass ${API_UPSTREAM};
        proxy_set_header Host $host;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
    }

    # Ficheiros com hash no nome: cache longa.
    # (add_header num location anula os do server, por isso os cabeçalhos de segurança repetem-se.)
    location /assets/ {
        add_header Cache-Control "public, max-age=31536000, immutable";
        add_header X-Content-Type-Options nosniff;
        try_files $uri =404;
    }

    # SPA fallback
    location / {
        add_header Cache-Control "no-cache";
        add_header X-Content-Type-Options nosniff;
        add_header Referrer-Policy strict-origin-when-cross-origin;
        try_files $uri /index.html;
    }

    gzip on;
    gzip_types text/plain text/css application/javascript application/json image/svg+xml;
}