server {
    listen 80;
    server_name _;
    root /usr/share/nginx/html;
    index index.html;

    # Gzip compression
    gzip on;
    gzip_vary on;
    gzip_min_length 1024;
    gzip_types text/plain text/css text/xml application/json application/javascript application/xml+rss image/svg+xml;

    # Health check endpoint
    location /healthz {
        access_log off;
        return 200 "OK";
        add_header Content-Type text/plain;
    }

    # Proxy API calls to the backend
    location /api/ {
        proxy_pass http://backend:8080;
        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_read_timeout 60s;
    }

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

    # SPA: redirect all routes to index.html
    location / {
        try_files $uri $uri/ /index.html;
    }
}