user  nginx;
worker_processes  auto;

error_log  /var/log/nginx/error.log warn;
pid        /var/run/nginx.pid;

events {
  worker_connections  1024;
}

http {
  include       /etc/nginx/mime.types;
  default_type  application/octet-stream;

  log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                    '$status $body_bytes_sent "$http_referer" '
                    '"$http_user_agent" "$http_x_forwarded_for"';

  access_log  /var/log/nginx/access.log  main;

  sendfile        on;
  keepalive_timeout  65;

  # Security headers
  map $http_upgrade $connection_upgrade {
    default upgrade;
    ''      close;
  }

  # HTTP server: serve ACME challenge and redirect everything else to HTTPS
  server {
    listen 80;
    server_name _;

    # ACME challenge
    location ^~ /.well-known/acme-challenge/ {
      root /var/www/certbot;
    }

    location / {
      return 301 https://$host$request_uri;
    }
  }

  # HTTPS server
  server {
    listen 443 ssl http2;
    server_name _;

    # TLS certs (managed by certbot). We use fixed cert-name 'portal'
    ssl_certificate     /etc/letsencrypt/live/portal/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/portal/privkey.pem;
    ssl_session_timeout 1d;
    ssl_session_cache shared:SSL:10m;
    ssl_session_tickets off;

    # Modern TLS config
    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_ciphers 'ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256';
    ssl_prefer_server_ciphers off;

    # Security headers
    add_header Strict-Transport-Security "max-age=63072000; includeSubDomains; preload" always;
    add_header X-Frame-Options DENY;
    add_header X-Content-Type-Options nosniff;
    add_header Referrer-Policy no-referrer-when-downgrade;
    add_header Permissions-Policy "geolocation=(), microphone=(), camera=(), payment=(), usb=(), vr=()";
    add_header Content-Security-Policy "default-src 'self'; img-src 'self' data: blob:; style-src 'self' 'unsafe-inline'; script-src 'self'; font-src 'self' data:; connect-src 'self'; frame-ancestors 'none'; base-uri 'self'" always;

    # Request protections
    client_max_body_size 10m;
    send_timeout 30s;
    proxy_read_timeout 60s;
    proxy_send_timeout 60s;

    # Basic rate limiting for API
    limit_req_zone $binary_remote_addr zone=api_limit:10m rate=5r/s;

    # Portal (Next.js)
    location / {
      proxy_pass http://frontend:3000;
      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-Forwarded-Host $host;
      proxy_set_header X-Forwarded-Port $server_port;
    }

    # BFF API
    location /api/ {
      proxy_pass http://backend:4000/api/;
      proxy_http_version 1.1;
      proxy_set_header Upgrade $http_upgrade;
      proxy_set_header Connection $connection_upgrade;
      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-Forwarded-Host $host;
      proxy_set_header X-Forwarded-Port $server_port;

      # Apply rate limiting to API only
      limit_req zone=api_limit burst=10 nodelay;
    }

    # Health check
    location /healthz {
      proxy_pass http://frontend:3000/api/health;
    }
  }
}