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

    # gzip 압축
    gzip on;
    gzip_vary on;
    gzip_min_length 1024;
    gzip_types text/plain text/css text/xml text/javascript application/javascript application/json application/xml;

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

    # API 프록시
    location /api {
        proxy_pass http://backend:3000;
        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_cache_bypass $http_upgrade;
        
        # SSE 지원
        proxy_buffering off;
        proxy_read_timeout 86400s;
    }

    # SPA 라우팅 지원
    location / {
        try_files $uri $uri/ /index.html;
    }
}