package main

import (
	"log"
	"net/http"
	"net/url"

	"github.com/darkit/goproxy"
)

// ReverseProxyDelegate 反向代理委托
type ReverseProxyDelegate struct {
	goproxy.DefaultDelegate
	backendURL *url.URL
}

// ResolveBackend 解析后端服务器
func (d *ReverseProxyDelegate) ResolveBackend(req *http.Request) (string, error) {
	return d.backendURL.String(), nil
}

// RunReverseProxy 运行反向代理服务器
func main() {
	// 解析后端服务器地址
	backendURL, err := url.Parse("http://localhost:8081")
	if err != nil {
		return
	}

	// 创建反向代理委托
	delegate := &ReverseProxyDelegate{
		backendURL: backendURL,
	}

	// 创建代理实例
	proxy := goproxy.NewProxy(
		goproxy.WithDelegate(delegate),
		goproxy.WithReverseProxy(true),
	)

	// 启动代理服务器
	log.Println("反向代理服务器启动在 :8080")
	log.Printf("请求将被转发到: %s\n", backendURL.String())
	http.ListenAndServe(":8080", proxy)
}