# Auto-detect language from the browser's Accept-Language header, no JS
# involved (site stays static/no-JS per config.toml). Only the exact "/" is
# affected — deep links (e.g. someone shares /es/legal/rules/) are untouched.
# Fires once per visitor: a "tane_visited" cookie (set on every response) is
# checked first, so a later visit to "/" — including clicking "English" from
# the switcher on a non-English browser — is never redirected again.
map $http_accept_language $tane_lang {
    default en;
    ~*^es es;
    ~*^pt pt;
}

map $http_cookie $tane_seen {
    default 0;
    "~*tane_visited=1" 1;
}

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

    # Non-sensitive, no PII: only remembers "this browser has been here
    # before" so the auto-redirect below doesn't repeat. No Secure flag since
    # the value carries no sensitive data and this must also work over plain
    # http in local/dev previews; TLS is terminated upstream in production.
    add_header Set-Cookie "tane_visited=1; Path=/; Max-Age=31536000; SameSite=Lax" always;

    location = / {
        set $tane_redirect "";
        if ($tane_seen = 0) {
            set $tane_redirect $tane_lang;
        }
        if ($tane_redirect = en) {
            set $tane_redirect "";
        }
        if ($tane_redirect != "") {
            return 302 /$tane_redirect/;
        }
        try_files /index.html =404;
    }

    # Security headers. The page is fully static and self-contained: inline CSS
    # (needs style-src 'unsafe-inline'), same-origin images (+ data: URIs), no
    # third-party scripts. HSTS is host-scoped (no includeSubDomains) so it can't
    # affect sibling *.comunes.org sites. TLS is terminated upstream (assange).
    add_header Content-Security-Policy "default-src 'self'; img-src 'self' data:; style-src 'self' 'unsafe-inline'; script-src 'self'; font-src 'self'; base-uri 'self'; form-action 'self'; frame-ancestors 'none'" always;
    add_header X-Content-Type-Options "nosniff" always;
    add_header Referrer-Policy "strict-origin-when-cross-origin" always;
    add_header X-Frame-Options "DENY" always;
    add_header Permissions-Policy "geolocation=(), camera=(), microphone=(), interest-cohort=()" always;
    add_header Strict-Transport-Security "max-age=15768000" always;

    # Hugo emits directory-style URLs (/legal/privacy/index.html).
    location / {
        try_files $uri $uri/ =404;
    }

    # Long-cache fingerprinted assets and images; the HTML stays fresh.
    location ~* \.(png|jpg|jpeg|svg|webp|woff2?|css|js)$ {
        expires 7d;
        add_header Cache-Control "public";
    }

    error_page 404 /404.html;

    gzip on;
    gzip_types text/css application/javascript image/svg+xml application/xml;
    gzip_min_length 512;
}