# NGINX Configuration for go-first / URPI
# Deploy to /etc/nginx/nginx.conf

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

events {
    worker_connections 1024;
    use epoll;
    multi_accept on;
}

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

    # Logging
    log_format main '$remote_addr - $remote_user [$time_local] "$request" '
                    '$status $body_bytes_sent "$http_referer" '
                    '"$http_user_agent" "$http_x_forwarded_for" '
                    'rt=$request_time uct="$upstream_connect_time" '
                    'uht="$upstream_header_time" urt="$upstream_response_time"';

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

    # Performance
    sendfile on;
    tcp_nopush on;
    tcp_nodelay on;
    keepalive_timeout 65;
    types_hash_max_size 2048;
    server_tokens off;

    # Gzip
    gzip on;
    gzip_vary on;
    gzip_proxied any;
    gzip_comp_level 6;
    gzip_min_length 1000;
    gzip_types
        text/plain
        text/css
        text/xml
        text/javascript
        application/json
        application/javascript
        application/xml+rss
        application/atom+xml
        image/svg+xml;

    # Brotli (if available)
    # brotli on;
    # brotli_comp_level 6;
    # brotli_types text/plain text/css application/json application/javascript text/xml application/xml application/xml+rss text/javascript;

    # Rate limiting
    limit_req_zone $binary_remote_addr zone=api:10m rate=10r/s;
    limit_req_zone $binary_remote_addr zone=login:10m rate=5r/m;

    # Upstream
    upstream go_first_backend {
        server app:8080;
        keepalive 32;
    }

    # HTTP -> HTTPS redirect
    server {
        listen 80;
        listen [::]:80;
        server_name www.urpi.be urpi.be;

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

        # Redirect all other traffic to HTTPS
        location / {
            return 301 https://www.urpi.be$request_uri;
        }
    }

    # HTTPS server
    server {
        listen 443 ssl http2;
        listen [::]:443 ssl http2;
        server_name www.urpi.be urpi.be;

        # SSL Configuration
        ssl_certificate /etc/nginx/ssl/fullchain.pem;
        ssl_certificate_key /etc/nginx/ssl/privkey.pem;
        ssl_session_timeout 1d;
        ssl_session_cache shared:SSL:10m;
        ssl_session_tickets off;

        # Modern SSL config
        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:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384;
        ssl_prefer_server_ciphers off;

        # HSTS
        add_header Strict-Transport-Security "max-age=31536000" always;

        # OCSP Stapling
        ssl_stapling on;
        ssl_stapling_verify on;
        resolver 1.1.1.1 8.8.8.8 valid=300s;
        resolver_timeout 5s;

        # Security headers
        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' 'unsafe-eval'; style-src 'self' 'unsafe-inline'; img-src 'self' data: https:; font-src 'self' data:; connect-src 'self'; frame-ancestors 'none';" always;

        # Frontend static files
        root /var/www/html;
        index index.html;

        # Cache static assets
        location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff|woff2|ttf|eot)$ {
            expires 1y;
            add_header Cache-Control "public, immutable";
            try_files $uri =404;
        }

        # API routes
        location /api/ {
            limit_req zone=api burst=20 nodelay;

            proxy_pass http://go_first_backend;
            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_cache_bypass $http_upgrade;

            # Timeouts
            proxy_connect_timeout 5s;
            proxy_send_timeout 30s;
            proxy_read_timeout 30s;

            # Buffering
            proxy_buffering on;
            proxy_buffer_size 4k;
            proxy_buffers 8 4k;
        }

        # Health check endpoint (no rate limit)
        location /api/v1/health {
            proxy_pass http://go_first_backend;
            proxy_http_version 1.1;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            access_log off;
        }

        # SPA fallback - serve index.html for all other routes
        location / {
            try_files $uri $uri/ /index.html;

            # Cache HTML for short time
            add_header Cache-Control "no-cache, must-revalidate";
        }

        # Block access to hidden files
        location ~ /\. {
            deny all;
            access_log off;
            log_not_found off;
        }

        # Block access to backup/config files
        location ~* \.(env|log|conf|bak|backup|sql)$ {
            deny all;
            access_log off;
            log_not_found off;
        }
    }
}