# /etc/nginx/conf.d/drawit.conf
#
# Assumes:
#   - drawit is listening on 127.0.0.1:3000 (PORT=3000)
#   - TLS is terminated here at nginx (recommended)
#   - Certbot / Let's Encrypt has already issued a certificate
#
# Enable:
#   sudo nginx -t
#   sudo systemctl reload nginx

# ── Upstream ──────────────────────────────────────────────────────────────────

upstream drawit_backend {
  server 127.0.0.1:3000;
  # Keep a pool of connections to the backend so nginx does not open a new
  # TCP connection for every WebSocket upgrade.
  #keepalive 64;
}

server {
    listen 80;
    listen [::]:80;
    server_name your.domain.com;

    # Let's Encrypt ACME challenge — must be reachable over plain HTTP.
    location /.well-known/acme-challenge/ {
        root /var/www/certbot;
    }

    # Everything else redirects to HTTPS.
    location / {
        return 301 https://$host$request_uri;
    }
}

server {
    listen 443 ssl;
    listen [::]:443 ssl;
    http2 on;
    server_name your.domain.com;

    # Let's Encrypt Cert location
    ssl_certificate     /etc/letsencrypt/live/your.domain.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/your.domain.com/privkey.pem;

    # Modern TLS only — drops IE11 and very old Android.
    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_ciphers ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305;
    ssl_prefer_server_ciphers off;
    ssl_session_cache shared:SSL:10m;
    ssl_session_timeout 1d;
    ssl_session_tickets off;

    # Security Headers
    add_header Referrer-Policy                   "no-referrer"       always;
    add_header X-Content-Type-Options            "nosniff"           always;
    add_header X-Frame-Options                   "SAMEORIGIN"        always; # Or DENY
    add_header X-Permitted-Cross-Domain-Policies "none"              always;
    add_header X-Robots-Tag                      "noindex, nofollow" always;
    add_header X-XSS-Protection                  "1; mode=block"     always;
    add_header Permissions-Policy                "geolocation=(self), midi=(self), sync-xhr=(self), microphone=(self), camera=(self), magnetometer=(self), gyroscope=(self), fullscreen=(self), payment=(self), interest-cohort=()";
    #add_header Strict-Transport-Security "max-age=63072000; includeSubDomains" always; # Only enable this when you are ready!

    # Logging
    access_log /var/log/nginx/drawit_access.log;
    error_log /var/log/nginx/drawit_error.log info;
    # Or, disable logging altogether
    #access_log off;
    #error_log /dev/null crit;

    # Proxy rules
    location / {
        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 https;
        proxy_set_header Host $http_host;
        proxy_redirect off;
        proxy_ssl_verify off;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
        proxy_read_timeout 86400;
        proxy_http_version 1.1;
        proxy_pass http://drawit_backend;
    }

    # Block sensitive files
    location ~* /(data|node_modules|src)/.*\.(db|db-shm|db-wal)$ {
        deny all;
    }
    location ~* /(node_modules|src)/.*$ {
        deny all;
    }
    # Block everything else
    # Anything else gets a 444 (faster but confusing, change to 404 if you want) from nginx before it reaches the backend.
    location ~* \.(php|asp|aspx|jsp|cgi|go|env|env.local|mod|sum|yaml|yml|md|gitignore|git|github|gitea|ts|mjs)$ {
        return 444;
    }

}