package conn

import (
	"io"
	"net"
	"sync"
	"testing"
	"time"

	"git.zeroonesoft.cn/golib/zogo/flow"
	"git.zeroonesoft.cn/golib/zogo/rate"
)

func TestConnWriteReadFlow(t *testing.T) {
	c1, c2 := net.Pipe()
	defer c2.Close()

	f := &flow.Flow{}
	wg := &sync.WaitGroup{}
	wg.Add(1)
	c := NewConn(c1, nil, f, wg)
	defer c.Close()

	// 持续消费对端数据，避免 Write 阻塞
	done := make(chan struct{})
	go func() {
		buf := make([]byte, 1024)
		for {
			if _, err := c2.Read(buf); err != nil {
				close(done)
				return
			}
		}
	}()

	if n, err := c.Write([]byte("hello")); err != nil || n != 5 {
		t.Fatalf("Write = %d, %v, want 5, nil", n, err)
	}

	// 对端写入，本端读取
	go func() {
		c2.Write([]byte("abcde"))
	}()
	buf := make([]byte, 5)
	if err := c.SetReadDeadline(time.Now().Add(2 * time.Second)); err != nil {
		t.Logf("SetReadDeadline: %v（conn.Read 未实现 Deadline 转发）", err)
	}
	n, err := c.Read(buf)
	if err != nil || n != 5 {
		t.Fatalf("Read = %d, %v, want 5, nil", n, err)
	}

	// conn 包设计：Read/Write 均计入 SendFlow
	send, _ := f.Get()
	if send != 10 {
		t.Errorf("Flow SendFlow = %d, want 10（读写各计 5）", send)
	}

	// 触发消费者协程退出：关闭本端后其阻塞在 c2.Read 的 goroutine 会返回
	c.Close()
	<-done
}

func TestConnCloseIdempotent(t *testing.T) {
	c1, c2 := net.Pipe()
	defer c2.Close()

	wg := &sync.WaitGroup{}
	wg.Add(1)
	c := NewConn(c1, nil, nil, wg)

	if err := c.Close(); err != nil {
		t.Fatalf("第一次 Close: %v", err)
	}
	_ = c.Close() // 第二次 Close 不应重复 wg.Done

	finished := make(chan struct{})
	go func() {
		wg.Wait()
		close(finished)
	}()
	select {
	case <-finished:
		// 正常：wg 只被 Done 一次
	case <-time.After(time.Second):
		t.Error("Close 幂等性失败：wg 被多次 Done 或未被 Done")
	}
}

func TestConnAddr(t *testing.T) {
	c1, c2 := net.Pipe()
	defer c1.Close()
	defer c2.Close()

	c := NewConn(c1, nil, nil, nil)
	defer c.Close()

	if c.LocalAddr() == nil || c.RemoteAddr() == nil {
		t.Error("LocalAddr/RemoteAddr 不应为 nil")
	}
}

func TestConnWithRateLimit(t *testing.T) {
	c1, c2 := net.Pipe()
	defer c2.Close()

	// 不限速：Add 应立即返回
	r := rate.NewRate(0)
	wg := &sync.WaitGroup{}
	wg.Add(1)
	c := NewConn(c1, r, nil, wg)
	defer c.Close()

	readerDone := make(chan struct{})
	go func() {
		defer close(readerDone)
		buf := make([]byte, 1024)
		for {
			if _, err := c2.Read(buf); err != nil {
				return
			}
		}
	}()

	if _, err := io.WriteString(c, "x"); err != nil {
		t.Fatalf("Write: %v", err)
	}

	// 关闭本端使消费者协程退出，避免 goroutine 泄漏
	_ = c.Close()
	<-readerDone
}