# nginx config for llm.home.ms - kokorotts-server reverse proxy
# Addresses: issues #15-#24 (OPE-Web security audit findings)

server {
    listen 443 ssl http2;
    server_name llm.home.ms;

    # SSL configuration
    ssl_certificate /etc/letsencrypt/live/llm.home.ms/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/llm.home.ms/privkey.pem;
    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_ciphers HIGH:!aNULL:!MD5;
    ssl_prefer_server_ciphers on;
    ssl_session_cache shared:SSL:10m;
    ssl_session_timeout 10m;

    # Issue #21: Hide server version
    server_tokens off;

    # Issue #16: HSTS header (1 year, include subdomains)
    add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;

    # Issue #17: Content-Security-Policy
    # Allow Swagger UI inline scripts/styles while restricting external sources
    add_header Content-Security-Policy "default-src 'self'; script-src 'self' 'unsafe-inline' 'unsafe-eval'; style-src 'self' 'unsafe-inline'; img-src 'self' data:; font-src 'self'; connect-src 'self'; frame-ancestors 'none'; base-uri 'self'; form-action 'self';" always;

    # Issue #18: X-Frame-Options - prevent clickjacking
    add_header X-Frame-Options "DENY" always;

    # Issue #19: X-Content-Type-Options - prevent MIME sniffing
    add_header X-Content-Type-Options "nosniff" always;

    # Issue #20: Referrer-Policy
    add_header Referrer-Policy "strict-origin-when-cross-origin" always;

    # Permissions Policy
    add_header Permissions-Policy "geolocation=(), microphone=(), camera=()" always;

    # Issue #15: Restrict Swagger UI access - require authentication
    location /docs {
        auth_basic "API Documentation - Restricted Access";
        auth_basic_user_file /etc/nginx/.htpasswd;
        proxy_pass http://127.0.0.1:5012;
        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;
    }

    location /openapi.json {
        auth_basic "API Documentation - Restricted Access";
        auth_basic_user_file /etc/nginx/.htpasswd;
        proxy_pass http://127.0.0.1:5012;
        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;
    }

    # Main API endpoint
    location /tts {
        proxy_pass http://127.0.0.1:5012;
        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;

        # Rate limiting
        limit_req zone=tts_zone burst=5 nodelay;
    }

    # Health check endpoint (no auth needed)
    location /health {
        proxy_pass http://127.0.0.1:5012;
        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;
    }

    # Issue #22: Fix protocol-relative links by redirecting absolute paths
    # These locations handle the broken //ui, //fallback/login, //ui/model_hub_table links
    location /ui/ {
        proxy_pass http://127.0.0.1:5012/ui/;
        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;
    }

    location /fallback/login {
        proxy_pass http://127.0.0.1:5012/fallback/login;
        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;
    }

    location /ui/model_hub_table {
        proxy_pass http://127.0.0.1:5012/ui/model_hub_table;
        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;
    }

    # Default: proxy to Flask app
    location / {
        proxy_pass http://127.0.0.1:5012;
        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;
    }

    # Block access to version info
    location ~* /version {
        return 403;
    }
}

# HTTP -> HTTPS redirect
server {
    listen 80;
    server_name llm.home.ms;
    return 301 https://$server_name$request_uri;
}

# Rate limiting zone (add to http block in nginx.conf)
# limit_req_zone $binary_remote_addr zone=tts_zone:10m rate=10r/s;