// HTTP 穿透测试：验证"隧道模式全用 tcp"成立——真实 HTTP 服务（含 keep-alive、
// 大 body）经纯 TCP 隧道完整可用，无需 zonat 的 http 反向代理模式。
package e2e

import (
	"bytes"
	"crypto/rand"
	"encoding/json"
	"io"
	"net/http"
	"net/http/httptest"
	"strconv"
	"testing"
	"time"

	"git.zeroonesoft.cn/golib/zonat/agent"
	"git.zeroonesoft.cn/golib/zonat/internal/node"
)

func startHTTPServer(t *testing.T) *httptest.Server {
	t.Helper()
	mux := http.NewServeMux()
	mux.HandleFunc("/hello", func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Content-Type", "application/json")
		json.NewEncoder(w).Encode(map[string]string{"hello": "zonat", "via": "tcp-tunnel"})
	})
	mux.HandleFunc("/echo", func(w http.ResponseWriter, r *http.Request) {
		if r.Method != http.MethodPost {
			http.Error(w, "POST only", http.StatusMethodNotAllowed)
			return
		}
		body, err := io.ReadAll(r.Body)
		if err != nil {
			http.Error(w, err.Error(), http.StatusBadRequest)
			return
		}
		w.Write(body)
	})
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)
	return srv
}

// registerHTTP 把 httptest.Server 登记为一条隧道，返回公网端口
func registerHTTP(t *testing.T, n *node.Node, a *agent.Agent, srv *httptest.Server, id string) int {
	t.Helper()
	port, err := a.RegisterTunnel(buildTunnel(t, n, a, id, srv.Listener.Addr().String(), 0))
	if err != nil {
		t.Fatal(err)
	}
	return port
}

func TestHTTPGetPostThroughTunnel(t *testing.T) {
	srv := startHTTPServer(t)
	n, a := startEnv(t)
	port := registerHTTP(t, n, a, srv, "http-tunnel")
	base := "http://127.0.0.1:" + strconv.Itoa(port)

	// GET
	resp, err := http.Get(base + "/hello")
	if err != nil {
		t.Fatal(err)
	}
	var body map[string]string
	if err := json.NewDecoder(resp.Body).Decode(&body); err != nil {
		t.Fatal(err)
	}
	resp.Body.Close()
	if resp.StatusCode != http.StatusOK || body["hello"] != "zonat" {
		t.Fatalf("GET /hello 异常: status=%d body=%v", resp.StatusCode, body)
	}

	// POST 大 body（1MB，跨 smux 多帧）
	payload := make([]byte, 1<<20)
	if _, err := rand.Read(payload); err != nil {
		t.Fatal(err)
	}
	resp2, err := http.Post(base+"/echo", "application/octet-stream", bytes.NewReader(payload))
	if err != nil {
		t.Fatal(err)
	}
	got, err := io.ReadAll(resp2.Body)
	resp2.Body.Close()
	if err != nil {
		t.Fatal(err)
	}
	if resp2.StatusCode != http.StatusOK || !bytes.Equal(got, payload) {
		t.Fatalf("POST /echo 异常: status=%d len(got)=%d", resp2.StatusCode, len(got))
	}
}

func TestHTTPKeepAliveThroughTunnel(t *testing.T) {
	srv := startHTTPServer(t)
	n, a := startEnv(t)
	port := registerHTTP(t, n, a, srv, "http-ka")

	// 同一 client 复用 TCP 连接（keep-alive），10 次请求走同一条隧道流
	client := &http.Client{Timeout: 10 * time.Second}
	for i := 0; i < 10; i++ {
		resp, err := client.Get("http://127.0.0.1:" + strconv.Itoa(port) + "/hello")
		if err != nil {
			t.Fatal(err)
		}
		resp.Body.Close()
		if resp.StatusCode != http.StatusOK {
			t.Fatalf("第 %d 次请求异常: %d", i+1, resp.StatusCode)
		}
	}
}