# -----------------------------------------------------------------------------
# Serves the SPA and proxies /api to the Django container.
#
# Putting both behind one origin means the browser never issues a cross-origin
# request, so no CORS pre-flight, no third-party cookie rules, and the API can
# keep its allow-list empty in production.
# -----------------------------------------------------------------------------
server {
    listen 8080;
    server_name _;

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

    # --- Security headers ----------------------------------------------------
    add_header X-Content-Type-Options "nosniff" always;
    add_header X-Frame-Options "DENY" always;
    add_header Referrer-Policy "strict-origin-when-cross-origin" always;
    add_header Permissions-Policy "camera=(), microphone=(), geolocation=(), interest-cohort=()" always;
    # The bundle is fully self-hosted, so the policy can stay strict.
    add_header Content-Security-Policy "default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline'; img-src 'self' data:; connect-src 'self'; font-src 'self'; frame-ancestors 'none'; base-uri 'self'; form-action 'self'" always;

    server_tokens off;
    client_max_body_size 2m;

    gzip on;
    gzip_types text/css application/javascript application/json image/svg+xml;
    gzip_min_length 1024;

    location = /healthz {
        access_log off;
        add_header Content-Type text/plain;
        return 200 'ok';
    }

    # Hashed assets never change under the same name - cache them hard.
    location /assets/ {
        expires 1y;
        add_header Cache-Control "public, immutable";
        try_files $uri =404;
    }

    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_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header X-Request-ID $request_id;
        proxy_connect_timeout 5s;
        proxy_read_timeout 30s;
    }

    # Django admin and API documentation share the backend origin.
    location ~ ^/(admin|static)/ {
        proxy_pass http://backend:8000;
        proxy_set_header Host $host;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
    }

    # Client-side routing: unknown paths fall back to the SPA shell.
    location / {
        try_files $uri $uri/ /index.html;
        add_header Cache-Control "no-cache";
    }
}