package starnet

import (
	"io"
	"net"
	"net/http"
	"net/http/httptest"
	"testing"
	"time"
)

func TestRequestTimeoutDoesNotMutateClientTimeout(t *testing.T) {
	s := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		time.Sleep(200 * time.Millisecond)
		w.WriteHeader(http.StatusOK)
	}))
	defer s.Close()

	client := NewClientNoErr()
	baseTimeout := client.HTTPClient().Timeout

	_, err := client.Get(s.URL, WithTimeout(80*time.Millisecond))
	if err == nil {
		t.Fatal("expected request timeout error")
	}

	if client.HTTPClient().Timeout != baseTimeout {
		t.Fatalf("client timeout mutated: got=%v want=%v", client.HTTPClient().Timeout, baseTimeout)
	}

	resp, err := client.Get(s.URL, WithTimeout(400*time.Millisecond))
	if err != nil {
		t.Fatalf("second request should succeed with larger timeout: %v", err)
	}
	defer resp.Close()
}

func TestRequestTimeoutNoLingeringConnDeadline(t *testing.T) {
	s := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		_, _ = io.Copy(io.Discard, r.Body)
		w.WriteHeader(http.StatusOK)
		_, _ = w.Write([]byte("ok"))
	}))
	defer s.Close()

	client := NewClientNoErr()

	resp1, err := client.Post(s.URL, WithBodyString("first"), WithTimeout(120*time.Millisecond))
	if err != nil {
		t.Fatalf("first request should succeed: %v", err)
	}
	_ = resp1.Close()

	// 如果请求超时依赖连接级绝对 deadline，经过该等待后复用连接会出现误超时。
	time.Sleep(220 * time.Millisecond)

	resp2, err := client.Post(s.URL, WithBodyString("second"), WithTimeout(1*time.Second))
	if err != nil {
		t.Fatalf("second request should not be affected by previous timeout window: %v", err)
	}
	_ = resp2.Close()
}

func TestConnReadDeadlineTimeoutAndRecover(t *testing.T) {
	ln, err := net.Listen("tcp", "127.0.0.1:0")
	if err != nil {
		t.Fatalf("listen error: %v", err)
	}
	defer ln.Close()

	done := make(chan struct{})
	go func() {
		defer close(done)
		conn, err := ln.Accept()
		if err != nil {
			return
		}
		defer conn.Close()

		time.Sleep(180 * time.Millisecond)
		_, _ = conn.Write([]byte("x"))
	}()

	c, err := Dial("tcp", ln.Addr().String())
	if err != nil {
		t.Fatalf("dial error: %v", err)
	}
	defer c.Close()

	if err := c.SetReadDeadline(time.Now().Add(60 * time.Millisecond)); err != nil {
		t.Fatalf("set read deadline error: %v", err)
	}

	buf := make([]byte, 1)
	_, err = c.Read(buf)
	if err == nil {
		t.Fatal("expected read timeout error")
	}
	if ne, ok := err.(net.Error); !ok || !ne.Timeout() {
		t.Fatalf("expected net timeout error, got: %v", err)
	}

	if err := c.SetReadDeadline(time.Time{}); err != nil {
		t.Fatalf("clear read deadline error: %v", err)
	}

	if _, err := io.ReadFull(c, buf); err != nil {
		t.Fatalf("read after clearing deadline should succeed: %v", err)
	}
	if string(buf) != "x" {
		t.Fatalf("unexpected payload: %q", string(buf))
	}

	<-done
}