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;

    # Performance
    sendfile on;
    tcp_nopush on;
    tcp_nodelay on;
    keepalive_timeout 65;
    types_hash_max_size 2048;
    client_max_body_size 100M;

    # 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 font/truetype font/opentype
               application/vnd.ms-fontobject image/svg+xml;

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

    # Upstream API
    upstream api {
        least_conn;
        server api:8000 max_fails=3 fail_timeout=30s;
        keepalive 32;
    }

    # HTTP redirect to HTTPS
    server {
        listen 80;
        server_name mtd.runfoo.run www.mtd.runfoo.run;

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

        # Redirect all other traffic to HTTPS
        location / {
            return 301 https://$server_name$request_uri;
        }
    }

    # HTTPS API server
    server {
        listen 443 ssl http2;
        server_name mtd.runfoo.run;

        # SSL certificates (Let's Encrypt)
        ssl_certificate /etc/letsencrypt/live/mtd.runfoo.run/fullchain.pem;
        ssl_certificate_key /etc/letsencrypt/live/mtd.runfoo.run/privkey.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 Strict-Transport-Security "max-age=31536000; includeSubDomains" always;
        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 "strict-origin-when-cross-origin" always;
        add_header Permissions-Policy "geolocation=(), microphone=(), camera=()" always;

        # Health check endpoint
        location /health {
            access_log off;
            proxy_pass http://api;
            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;
        }

        # API endpoints with rate limiting
        location /api/v1/auth/ {
            limit_req zone=auth_limit burst=10 nodelay;

            proxy_pass http://api;
            proxy_http_version 1.1;
            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 Connection "";
            proxy_redirect off;
        }

        location /api/v1/ {
            limit_req zone=api_limit burst=20 nodelay;

            proxy_pass http://api;
            proxy_http_version 1.1;
            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 Connection "";
            proxy_redirect off;

            # Timeouts
            proxy_connect_timeout 10s;
            proxy_send_timeout 60s;
            proxy_read_timeout 60s;
        }

        # API documentation
        location /docs {
            proxy_pass http://api;
            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 /redoc {
            proxy_pass http://api;
            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 {
            proxy_pass http://api;
            proxy_set_header Host $host;
        }

        # Frontend static files
        location / {
            root /usr/share/nginx/html;
            try_files $uri $uri/ /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";
            }
        }

        # Deny access to sensitive files
        location ~ /\. {
            deny all;
        }
    }

    # HTTP health check (for load balancers)
    server {
        listen 8080;
        server_name _;

        location /health {
            access_log off;
            return 200 "healthy\n";
            add_header Content-Type text/plain;
        }

        location / {
            return 404;
        }
    }
}