server {
    listen 80;
    server_name admin.mnemo-cards.online;

    # Redirect HTTP to HTTPS
    return 301 https://$server_name$request_uri;
}

server {
    listen 443 ssl http2;
    server_name admin.mnemo-cards.online;

    # SSL configuration - Let's Encrypt
    ssl_certificate /etc/letsencrypt/live/admin.mnemo-cards.online/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/admin.mnemo-cards.online/privkey.pem;

    # Fallback to self-signed certificates if Let's Encrypt fails
    # ssl_certificate /etc/ssl/certs/nginx-selfsigned.crt;
    # ssl_certificate_key /etc/ssl/private/nginx-selfsigned.key;
    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_ciphers ECDHE-RSA-AES256-GCM-SHA512:DHE-RSA-AES256-GCM-SHA512:ECDHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES256-GCM-SHA384;
    ssl_prefer_server_ciphers off;

    # Security headers (enhanced for admin panel)
    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 Content-Security-Policy "default-src 'self'; script-src 'self' 'unsafe-inline'; style-src 'self' 'unsafe-inline'; img-src 'self' data: https:; font-src 'self' data:; connect-src 'self' https://api.mnemo-cards.online;" always;
    add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;

    # Root directory for admin panel
    root /var/www/mnemo_cards_admin;
    index index.html;

    # Gzip compression
    gzip on;
    gzip_vary on;
    gzip_min_length 1024;
    gzip_types text/plain text/css text/xml text/javascript application/javascript application/json;

    # Main location block
    location / {
        try_files $uri $uri/ /index.html;

        # Cache static assets
        location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff|woff2|ttf|eot)$ {
            expires 1h;  # Shorter cache for admin panel
            add_header Cache-Control "private, must-revalidate";
        }
    }

    # Security - deny access to hidden files and sensitive paths
    location ~ /\. {
        deny all;
    }

    location ~ ^/admin/ {
        deny all;  # Prevent access to any /admin/ paths that might be exposed
    }

    # Rate limiting for admin panel
    limit_req zone=admin burst=10 nodelay;
    limit_req_status 429;

    # Log admin access
    access_log /var/log/nginx/admin_access.log;
    error_log /var/log/nginx/admin_error.log;
}

# Rate limiting zone for admin panel
limit_req_zone $binary_remote_addr zone=admin:10m rate=5r/m;