user nginx;
worker_processes auto;
error_log /var/log/nginx/error.log warn;
pid /var/run/nginx.pid;

events {
    worker_connections 1024;
    use epoll;
}

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;
    tcp_nopush on;
    tcp_nodelay on;
    keepalive_timeout 65;
    types_hash_max_size 2048;
    client_max_body_size 2048M;

    # Gzip compression
    gzip on;
    gzip_vary on;
    gzip_proxied any;
    gzip_comp_level 6;
    gzip_types text/plain text/css text/xml text/javascript application/json application/javascript application/xml+rss application/rss+xml;

    # Upstream to Flask application
    upstream digiserver_app {
        server digiserver-app:5000;
        keepalive 32;
    }

    # HTTP Server - redirect to HTTPS
    server {
        listen 80 default_server;
        listen [::]:80 default_server;
        server_name _;

        # Allow ACME challenges for Let's Encrypt
        location /.well-known/acme-challenge/ {
            root /var/www/certbot;
        }

        # Redirect HTTP to HTTPS for non-ACME requests
        location / {
            return 301 https://$host$request_uri;
        }
    }

    # HTTPS Server (with self-signed cert by default)
    server {
        listen 443 ssl http2 default_server;
        listen [::]:443 ssl http2 default_server;
        server_name localhost;

        # SSL certificate paths (will be volume-mounted)
        ssl_certificate /etc/nginx/ssl/cert.pem;
        ssl_certificate_key /etc/nginx/ssl/key.pem;

        # SSL Configuration
        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;

        # Security Headers
        add_header X-Frame-Options "SAMEORIGIN" always;
        add_header X-Content-Type-Options "nosniff" always;
        add_header X-XSS-Protection "1; mode=block" always;
        add_header Referrer-Policy "no-referrer-when-downgrade" always;
        add_header Content-Security-Policy "default-src 'self' http: https: data: blob: 'unsafe-inline'" always;
        
        # CORS Headers for API endpoints (allows player device connections)
        add_header 'Access-Control-Allow-Origin' '*' always;
        add_header 'Access-Control-Allow-Methods' 'GET, POST, PUT, DELETE, OPTIONS' always;
        add_header 'Access-Control-Allow-Headers' 'Content-Type, Authorization' always;
        add_header 'Access-Control-Max-Age' '3600' always;

        # Handle OPTIONS requests for CORS preflight
        if ($request_method = 'OPTIONS') {
            return 204;
        }

        # Proxy settings
        location / {
            proxy_pass http://digiserver_app;
            proxy_http_version 1.1;
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header 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 $server_name;
            proxy_set_header X-Forwarded-Port $server_port;

            # Timeouts for large uploads
            proxy_connect_timeout 300s;
            proxy_send_timeout 300s;
            proxy_read_timeout 300s;

            # Buffering
            proxy_buffering on;
            proxy_buffer_size 128k;
            proxy_buffers 4 256k;
            proxy_busy_buffers_size 256k;
        }

        # Static files caching
        location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff|woff2|ttf|eot)$ {
            proxy_pass http://digiserver_app;
            proxy_cache_valid 200 60d;
            expires 60d;
            add_header Cache-Control "public, immutable";
        }
    }

    # Additional server blocks for custom domains can be included here
    include /etc/nginx/conf.d/*.conf;
}