package wscat

import (
	"bufio"
	"bytes"
	"compress/flate"
	"crypto/x509"
	"encoding/json"
	"errors"
	"fmt"
	"io"
	"math/rand"
	"net"
	"net/http"
	"net/http/httptest"
	"net/url"
	"os"
	"reflect"
	"strings"
	"sync"
	"sync/atomic"
	"testing"
	"testing/internal/testdeps"
	"testing/iotest"
	"time"

	g "gobang"
)



var cstUpgrader = Upgrader{
	Subprotocols:      []string{"p0", "p1"},
	ReadBufferSize:    1024,
	WriteBufferSize:   1024,
	EnableCompression: true,
	Error: func(w http.ResponseWriter, r *http.Request, status int, reason error) {
		http.Error(w, reason.Error(), status)
	},
}

type cstHandler struct {
	*testing.T
	s *cstServer
}

type cstServer struct {
	URL    string
	Server *httptest.Server
	wg     sync.WaitGroup
}

const (
	cstPath       = "/a/b"
	cstRawQuery   = "x=y"
	cstRequestURI = cstPath + "?" + cstRawQuery
)

func (s *cstServer) Close() {
	s.Server.Close()
	// Wait for handler functions to complete.
	s.wg.Wait()
}

func newServer(t *testing.T) *cstServer {
	var s cstServer
	s.Server = httptest.NewServer(cstHandler{T: t, s: &s})
	s.Server.URL += cstRequestURI
	s.URL = makeWsProto(s.Server.URL)
	return &s
}

func newTLSServer(t *testing.T) *cstServer {
	var s cstServer
	s.Server = httptest.NewTLSServer(cstHandler{T: t, s: &s})
	s.Server.URL += cstRequestURI
	s.URL = makeWsProto(s.Server.URL)
	return &s
}

func (t cstHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	// Because tests wait for a response from a server, we are guaranteed that
	// the wait group count is incremented before the test waits on the group
	// in the call to (*cstServer).Close().
	t.s.wg.Add(1)
	defer t.s.wg.Done()

	if r.URL.Path != cstPath {
		t.Logf("path=%v, want %v", r.URL.Path, cstPath)
		http.Error(w, "bad path", http.StatusBadRequest)
		return
	}
	if r.URL.RawQuery != cstRawQuery {
		t.Logf("query=%v, want %v", r.URL.RawQuery, cstRawQuery)
		http.Error(w, "bad path", http.StatusBadRequest)
		return
	}
	ws, err := cstUpgrader.Upgrade(w, r, http.Header{"Set-Cookie": {"sessionID=1234"}})
	if err != nil {
		t.Logf("Upgrade: %v", err)
		return
	}
	defer ws.Close()

	if ws.Subprotocol() != "p1" {
		t.Logf("Subprotocol() = %s, want p1", ws.Subprotocol())
		ws.Close()
		return
	}
	op, rd, err := ws.NextReader()
	if err != nil {
		t.Logf("NextReader: %v", err)
		return
	}
	wr, err := ws.NextWriter(op)
	if err != nil {
		t.Logf("NextWriter: %v", err)
		return
	}
	if _, err = io.Copy(wr, rd); err != nil {
		t.Logf("NextWriter: %v", err)
		return
	}
	if err := wr.Close(); err != nil {
		t.Logf("Close: %v", err)
		return
	}
}

func makeWsProto(s string) string {
	return "ws" + strings.TrimPrefix(s, "http")
}

func sendRecv(t *testing.T, ws *Conn) {
	const message = "Hello World!"
	if err := ws.SetWriteDeadline(time.Now().Add(time.Second)); err != nil {
		t.Fatalf("SetWriteDeadline: %v", err)
	}
	if err := ws.WriteMessage(TextMessage, []byte(message)); err != nil {
		t.Fatalf("WriteMessage: %v", err)
	}
	if err := ws.SetReadDeadline(time.Now().Add(time.Second)); err != nil {
		t.Fatalf("SetReadDeadline: %v", err)
	}
	_, p, err := ws.ReadMessage()
	if err != nil {
		t.Fatalf("ReadMessage: %v", err)
	}
	if string(p) != message {
		t.Fatalf("message=%s, want %s", p, message)
	}
}

func rootCAs(t *testing.T, s *httptest.Server) *x509.CertPool {
	certs := x509.NewCertPool()
	for _, c := range s.TLS.Certificates {
		roots, err := x509.ParseCertificates(c.Certificate[len(c.Certificate)-1])
		if err != nil {
			t.Fatalf("error parsing server's root cert: %v", err)
		}
		for _, root := range roots {
			certs.AddCert(root)
		}
	}
	return certs
}

// requireDeadlineNetConn fails the current test when Read or Write are called
// with no deadline.
type requireDeadlineNetConn struct {
	t                  *testing.T
	c                  net.Conn
	readDeadlineIsSet  bool
	writeDeadlineIsSet bool
}

func (c *requireDeadlineNetConn) SetDeadline(t time.Time) error {
	c.writeDeadlineIsSet = !t.Equal(time.Time{})
	c.readDeadlineIsSet = c.writeDeadlineIsSet
	return c.c.SetDeadline(t)
}

func (c *requireDeadlineNetConn) SetReadDeadline(t time.Time) error {
	c.readDeadlineIsSet = !t.Equal(time.Time{})
	return c.c.SetDeadline(t)
}

func (c *requireDeadlineNetConn) SetWriteDeadline(t time.Time) error {
	c.writeDeadlineIsSet = !t.Equal(time.Time{})
	return c.c.SetDeadline(t)
}

func (c *requireDeadlineNetConn) Write(p []byte) (int, error) {
	if !c.writeDeadlineIsSet {
		c.t.Fatalf("write with no deadline")
	}
	return c.c.Write(p)
}

func (c *requireDeadlineNetConn) Read(p []byte) (int, error) {
	if !c.readDeadlineIsSet {
		c.t.Fatalf("read with no deadline")
	}
	return c.c.Read(p)
}

func (c *requireDeadlineNetConn) Close() error         { return c.c.Close() }
func (c *requireDeadlineNetConn) LocalAddr() net.Addr  { return c.c.LocalAddr() }
func (c *requireDeadlineNetConn) RemoteAddr() net.Addr { return c.c.RemoteAddr() }

func TestBadMethod(t *testing.T) {
	s := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		ws, err := cstUpgrader.Upgrade(w, r, nil)
		if err == nil {
			t.Errorf("handshake succeeded, expect fail")
			ws.Close()
		}
	}))
	defer s.Close()

	req, err := http.NewRequest(http.MethodPost, s.URL, strings.NewReader(""))
	if err != nil {
		t.Fatalf("NewRequest returned error %v", err)
	}
	req.Header.Set("Connection", "upgrade")
	req.Header.Set("Upgrade", "websocket")
	req.Header.Set("Sec-Websocket-Version", "13")

	resp, err := http.DefaultClient.Do(req)
	if err != nil {
		t.Fatalf("Do returned error %v", err)
	}
	resp.Body.Close()
	if resp.StatusCode != http.StatusMethodNotAllowed {
		t.Errorf("Status = %d, want %d", resp.StatusCode, http.StatusMethodNotAllowed)
	}
}

func TestNoUpgrade(t *testing.T) {
	t.Parallel()
	s := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		ws, err := cstUpgrader.Upgrade(w, r, nil)
		if err == nil {
			t.Errorf("handshake succeeded, expect fail")
			ws.Close()
		}
	}))
	defer s.Close()

	req, err := http.NewRequest(http.MethodGet, s.URL, strings.NewReader(""))
	if err != nil {
		t.Fatalf("NewRequest returned error %v", err)
	}
	req.Header.Set("Connection", "upgrade")
	req.Header.Set("Sec-Websocket-Version", "13")

	resp, err := http.DefaultClient.Do(req)
	if err != nil {
		t.Fatalf("Do returned error %v", err)
	}
	resp.Body.Close()
	if u := resp.Header.Get("Upgrade"); u != "websocket" {
		t.Errorf("Upgrade response header is %q, want %q", u, "websocket")
	}
	if resp.StatusCode != http.StatusUpgradeRequired {
		t.Errorf("Status = %d, want %d", resp.StatusCode, http.StatusUpgradeRequired)
	}
}

type testLogWriter struct {
	t *testing.T
}

func (w testLogWriter) Write(p []byte) (int, error) {
	w.t.Logf("%s", p)
	return len(p), nil
}


type dataBeforeHandshakeResponseWriter struct {
	http.ResponseWriter
}

type dataBeforeHandshakeConnection struct {
	net.Conn
	io.Reader
}

func (c *dataBeforeHandshakeConnection) Read(p []byte) (int, error) {
	return c.Reader.Read(p)
}

func (w dataBeforeHandshakeResponseWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
	// Example single-frame masked text message from section 5.7 of the RFC.
	message := []byte{0x81, 0x85, 0x37, 0xfa, 0x21, 0x3d, 0x7f, 0x9f, 0x4d, 0x51, 0x58}
	n := len(message) / 2

	c, rw, err := http.NewResponseController(w.ResponseWriter).Hijack()
	if rw != nil {
		// Load first part of message into bufio.Reader. If the websocket
		// connection reads more than n bytes from the bufio.Reader, then the
		// test will fail with an unexpected EOF error.
		rw.Reader.Reset(bytes.NewReader(message[:n]))
		rw.Reader.Peek(n)
	}
	if c != nil {
		// Inject second part of message before data read from the network connection.
		c = &dataBeforeHandshakeConnection{
			Conn:   c,
			Reader: io.MultiReader(bytes.NewReader(message[n:]), c),
		}
	}
	return c, rw, err
}

var hostPortNoPortTests = []struct {
	u                    *url.URL
	hostPort, hostNoPort string
}{
	{&url.URL{Scheme: "ws", Host: "example.com"}, "example.com:80", "example.com"},
	{&url.URL{Scheme: "wss", Host: "example.com"}, "example.com:443", "example.com"},
	{&url.URL{Scheme: "ws", Host: "example.com:7777"}, "example.com:7777", "example.com"},
	{&url.URL{Scheme: "wss", Host: "example.com:7777"}, "example.com:7777", "example.com"},
}

func TestHostPortNoPort(t *testing.T) {
	for _, tt := range hostPortNoPortTests {
		hostPort, hostNoPort := hostPortNoPort(tt.u)
		if hostPort != tt.hostPort {
			t.Errorf("hostPortNoPort(%v) returned hostPort %q, want %q", tt.u, hostPort, tt.hostPort)
		}
		if hostNoPort != tt.hostNoPort {
			t.Errorf("hostPortNoPort(%v) returned hostNoPort %q, want %q", tt.u, hostNoPort, tt.hostNoPort)
		}
	}
}

type nopCloser struct{ io.Writer }

func (nopCloser) Close() error { return nil }

func TestTruncWriter(t *testing.T) {
	const data = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijlkmnopqrstuvwxyz987654321"
	for n := 1; n <= 10; n++ {
		var b bytes.Buffer
		w := &truncWriter{w: nopCloser{&b}}
		p := []byte(data)
		for len(p) > 0 {
			m := len(p)
			if m > n {
				m = n
			}
			_, _ = w.Write(p[:m])
			p = p[m:]
		}
		if b.String() != data[:len(data)-len(w.p)] {
			t.Errorf("%d: %q", n, b.String())
		}
	}
}

func textMessages(num int) [][]byte {
	messages := make([][]byte, num)
	for i := 0; i < num; i++ {
		msg := fmt.Sprintf("planet: %d, country: %d, city: %d, street: %d", i, i, i, i)
		messages[i] = []byte(msg)
	}
	return messages
}

func BenchmarkWriteNoCompression(b *testing.B) {
	w := io.Discard
	c := newTestConn(nil, w, false)
	messages := textMessages(100)
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		_ = c.WriteMessage(TextMessage, messages[i%len(messages)])
	}
	b.ReportAllocs()
}

func BenchmarkWriteWithCompression(b *testing.B) {
	w := io.Discard
	c := newTestConn(nil, w, false)
	messages := textMessages(100)
	c.enableWriteCompression = true
	c.newCompressionWriter = compressNoContextTakeover
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		_ = c.WriteMessage(TextMessage, messages[i%len(messages)])
	}
	b.ReportAllocs()
}

func TestValidCompressionLevel(t *testing.T) {
	c := newTestConn(nil, nil, false)
	for _, level := range []int{minCompressionLevel - 1, maxCompressionLevel + 1} {
		if err := c.SetCompressionLevel(level); err == nil {
			t.Errorf("no error for level %d", level)
		}
	}
	for _, level := range []int{minCompressionLevel, maxCompressionLevel} {
		if err := c.SetCompressionLevel(level); err != nil {
			t.Errorf("error for level %d", level)
		}
	}
}

// broadcastBench allows to run broadcast benchmarks.
// In every broadcast benchmark we create many connections, then send the same
// message into every connection and wait for all writes complete. This emulates
// an application where many connections listen to the same data - i.e. PUB/SUB
// scenarios with many subscribers in one channel.
type broadcastBench struct {
	w           io.Writer
	closeCh     chan struct{}
	doneCh      chan struct{}
	count       int32
	conns       []*broadcastConn
	compression bool
	usePrepared bool
}

type broadcastMessage struct {
	payload  []byte
	prepared *PreparedMessage
}

type broadcastConn struct {
	conn  *Conn
	msgCh chan *broadcastMessage
}

func newBroadcastConn(c *Conn) *broadcastConn {
	return &broadcastConn{
		conn:  c,
		msgCh: make(chan *broadcastMessage, 1),
	}
}

func newBroadcastBench(usePrepared, compression bool) *broadcastBench {
	bench := &broadcastBench{
		w:           io.Discard,
		doneCh:      make(chan struct{}),
		closeCh:     make(chan struct{}),
		usePrepared: usePrepared,
		compression: compression,
	}
	bench.makeConns(10000)
	return bench
}

func (b *broadcastBench) makeConns(numConns int) {
	conns := make([]*broadcastConn, numConns)

	for i := 0; i < numConns; i++ {
		c := newTestConn(nil, b.w, true)
		if b.compression {
			c.enableWriteCompression = true
			c.newCompressionWriter = compressNoContextTakeover
		}
		conns[i] = newBroadcastConn(c)
		go func(c *broadcastConn) {
			for {
				select {
				case msg := <-c.msgCh:
					if msg.prepared != nil {
						_ = c.conn.WritePreparedMessage(msg.prepared)
					} else {
						_ = c.conn.WriteMessage(TextMessage, msg.payload)
					}
					val := atomic.AddInt32(&b.count, 1)
					if val%int32(numConns) == 0 {
						b.doneCh <- struct{}{}
					}
				case <-b.closeCh:
					return
				}
			}
		}(conns[i])
	}
	b.conns = conns
}

func (b *broadcastBench) close() {
	close(b.closeCh)
}

func (b *broadcastBench) broadcastOnce(msg *broadcastMessage) {
	for _, c := range b.conns {
		c.msgCh <- msg
	}
	<-b.doneCh
}

func BenchmarkBroadcast(b *testing.B) {
	benchmarks := []struct {
		name        string
		usePrepared bool
		compression bool
	}{
		{"NoCompression", false, false},
		{"Compression", false, true},
		{"NoCompressionPrepared", true, false},
		{"CompressionPrepared", true, true},
	}
	payload := textMessages(1)[0]
	for _, bm := range benchmarks {
		b.Run(bm.name, func(b *testing.B) {
			bench := newBroadcastBench(bm.usePrepared, bm.compression)
			defer bench.close()
			b.ResetTimer()
			for i := 0; i < b.N; i++ {
				message := &broadcastMessage{
					payload: payload,
				}
				if bench.usePrepared {
					pm, _ := NewPreparedMessage(TextMessage, message.payload)
					message.prepared = pm
				}
				bench.broadcastOnce(message)
			}
			b.ReportAllocs()
		})
	}
}

var _ net.Error = errWriteTimeout

type fakeNetConn struct {
	io.Reader
	io.Writer
}

func (c fakeNetConn) Close() error                       { return nil }
func (c fakeNetConn) LocalAddr() net.Addr                { return localAddr }
func (c fakeNetConn) RemoteAddr() net.Addr               { return remoteAddr }
func (c fakeNetConn) SetDeadline(t time.Time) error      { return nil }
func (c fakeNetConn) SetReadDeadline(t time.Time) error  { return nil }
func (c fakeNetConn) SetWriteDeadline(t time.Time) error { return nil }

type fakeAddr int

var (
	localAddr  = fakeAddr(1)
	remoteAddr = fakeAddr(2)
)

func (a fakeAddr) Network() string {
	return "net"
}

func (a fakeAddr) String() string {
	return "str"
}

// newTestConn creates a connection backed by a fake network connection using
// default values for buffering.
func newTestConn(r io.Reader, w io.Writer, isServer bool) *Conn {
	return newConn(fakeNetConn{Reader: r, Writer: w}, isServer, 1024, 1024, nil, nil, nil)
}

func TestFraming(t *testing.T) {
	frameSizes := []int{
		0, 1, 2, 124, 125, 126, 127, 128, 129, 65534, 65535,
		// 65536, 65537
	}
	var readChunkers = []struct {
		name string
		f    func(io.Reader) io.Reader
	}{
		{"half", iotest.HalfReader},
		{"one", iotest.OneByteReader},
		{"asis", func(r io.Reader) io.Reader { return r }},
	}
	writeBuf := make([]byte, 65537)
	for i := range writeBuf {
		writeBuf[i] = byte(i)
	}
	var writers = []struct {
		name string
		f    func(w io.Writer, n int) (int, error)
	}{
		{"iocopy", func(w io.Writer, n int) (int, error) {
			nn, err := io.Copy(w, bytes.NewReader(writeBuf[:n]))
			return int(nn), err
		}},
		{"write", func(w io.Writer, n int) (int, error) {
			return w.Write(writeBuf[:n])
		}},
		{"string", func(w io.Writer, n int) (int, error) {
			return io.WriteString(w, string(writeBuf[:n]))
		}},
	}

	for _, compress := range []bool{false, true} {
		for _, isServer := range []bool{true, false} {
			for _, chunker := range readChunkers {

				var connBuf bytes.Buffer
				wc := newTestConn(nil, &connBuf, isServer)
				rc := newTestConn(chunker.f(&connBuf), nil, !isServer)
				if compress {
					wc.newCompressionWriter = compressNoContextTakeover
					rc.newDecompressionReader = decompressNoContextTakeover
				}
				for _, n := range frameSizes {
					for _, writer := range writers {
						name := fmt.Sprintf("z:%v, s:%v, r:%s, n:%d w:%s", compress, isServer, chunker.name, n, writer.name)

						w, err := wc.NextWriter(TextMessage)
						if err != nil {
							t.Errorf("%s: wc.NextWriter() returned %v", name, err)
							continue
						}
						nn, err := writer.f(w, n)
						if err != nil || nn != n {
							t.Errorf("%s: w.Write(writeBuf[:n]) returned %d, %v", name, nn, err)
							continue
						}
						err = w.Close()
						if err != nil {
							t.Errorf("%s: w.Close() returned %v", name, err)
							continue
						}

						opCode, r, err := rc.NextReader()
						if err != nil || opCode != TextMessage {
							t.Errorf("%s: NextReader() returned %d, r, %v", name, opCode, err)
							continue
						}

						t.Logf("frame size: %d", n)
						rbuf, err := io.ReadAll(r)
						if err != nil {
							t.Errorf("%s: ReadFull() returned rbuf, %v", name, err)
							continue
						}

						if len(rbuf) != n {
							t.Errorf("%s: len(rbuf) is %d, want %d", name, len(rbuf), n)
							continue
						}

						for i, b := range rbuf {
							if byte(i) != b {
								t.Errorf("%s: bad byte at offset %d", name, i)
								break
							}
						}
					}
				}
			}
		}
	}
}

func TestWriteControlDeadline(t *testing.T) {
	t.Parallel()
	message := []byte("hello")
	var connBuf bytes.Buffer
	c := newTestConn(nil, &connBuf, true)
	if err := c.WriteControl(PongMessage, message, time.Time{}); err != nil {
		t.Errorf("WriteControl(..., zero deadline) = %v, want nil", err)
	}
	if err := c.WriteControl(PongMessage, message, time.Now().Add(time.Second)); err != nil {
		t.Errorf("WriteControl(..., future deadline) = %v, want nil", err)
	}
	if err := c.WriteControl(PongMessage, message, time.Now().Add(-time.Second)); err == nil {
		t.Errorf("WriteControl(..., past deadline) = nil, want timeout error")
	}
}

func TestConcurrencyWriteControl(t *testing.T) {
	const message = "this is a ping/pong messsage"
	loop := 10
	workers := 10
	for i := 0; i < loop; i++ {
		var connBuf bytes.Buffer

		wg := sync.WaitGroup{}
		wc := newTestConn(nil, &connBuf, true)

		for i := 0; i < workers; i++ {
			wg.Add(1)
			go func() {
				defer wg.Done()
				if err := wc.WriteControl(PongMessage, []byte(message), time.Now().Add(time.Second)); err != nil {
					t.Errorf("concurrently wc.WriteControl() returned %v", err)
				}
			}()
		}

		wg.Wait()
		wc.Close()
	}
}

func TestControl(t *testing.T) {
	const message = "this is a ping/pong message"
	for _, isServer := range []bool{true, false} {
		for _, isWriteControl := range []bool{true, false} {
			name := fmt.Sprintf("s:%v, wc:%v", isServer, isWriteControl)
			var connBuf bytes.Buffer
			wc := newTestConn(nil, &connBuf, isServer)
			rc := newTestConn(&connBuf, nil, !isServer)
			if isWriteControl {
				_ = wc.WriteControl(PongMessage, []byte(message), time.Now().Add(time.Second))
			} else {
				w, err := wc.NextWriter(PongMessage)
				if err != nil {
					t.Errorf("%s: wc.NextWriter() returned %v", name, err)
					continue
				}
				if _, err := w.Write([]byte(message)); err != nil {
					t.Errorf("%s: w.Write() returned %v", name, err)
					continue
				}
				if err := w.Close(); err != nil {
					t.Errorf("%s: w.Close() returned %v", name, err)
					continue
				}
				var actualMessage string
				rc.SetPongHandler(func(s string) error { actualMessage = s; return nil })
				_, _, _ = rc.NextReader()
				if actualMessage != message {
					t.Errorf("%s: pong=%q, want %q", name, actualMessage, message)
					continue
				}
			}
		}
	}
}

// simpleBufferPool is an implementation of BufferPool for TestWriteBufferPool.
type simpleBufferPool struct {
	v interface{}
}

func (p *simpleBufferPool) Get() interface{} {
	v := p.v
	p.v = nil
	return v
}

func (p *simpleBufferPool) Put(v interface{}) {
	p.v = v
}

func TestWriteBufferPool(t *testing.T) {
	const message = "Now is the time for all good people to come to the aid of the party."

	var buf bytes.Buffer
	var pool simpleBufferPool
	rc := newTestConn(&buf, nil, false)

	// Specify writeBufferSize smaller than message size to ensure that pooling
	// works with fragmented messages.
	wc := newConn(fakeNetConn{Writer: &buf}, true, 1024, len(message)-1, &pool, nil, nil)

	if wc.writeBuf != nil {
		t.Fatal("writeBuf not nil after create")
	}

	// Part 1: test NextWriter/Write/Close

	w, err := wc.NextWriter(TextMessage)
	if err != nil {
		t.Fatalf("wc.NextWriter() returned %v", err)
	}

	if wc.writeBuf == nil {
		t.Fatal("writeBuf is nil after NextWriter")
	}

	writeBufAddr := &wc.writeBuf[0]

	if _, err := io.WriteString(w, message); err != nil {
		t.Fatalf("io.WriteString(w, message) returned %v", err)
	}

	if err := w.Close(); err != nil {
		t.Fatalf("w.Close() returned %v", err)
	}

	if wc.writeBuf != nil {
		t.Fatal("writeBuf not nil after w.Close()")
	}

	if wpd, ok := pool.v.(writePoolData); !ok || len(wpd.buf) == 0 || &wpd.buf[0] != writeBufAddr {
		t.Fatal("writeBuf not returned to pool")
	}

	opCode, p, err := rc.ReadMessage()
	if opCode != TextMessage || err != nil {
		t.Fatalf("ReadMessage() returned %d, p, %v", opCode, err)
	}

	if s := string(p); s != message {
		t.Fatalf("message is %s, want %s", s, message)
	}

	// Part 2: Test WriteMessage.

	if err := wc.WriteMessage(TextMessage, []byte(message)); err != nil {
		t.Fatalf("wc.WriteMessage() returned %v", err)
	}

	if wc.writeBuf != nil {
		t.Fatal("writeBuf not nil after wc.WriteMessage()")
	}

	if wpd, ok := pool.v.(writePoolData); !ok || len(wpd.buf) == 0 || &wpd.buf[0] != writeBufAddr {
		t.Fatal("writeBuf not returned to pool after WriteMessage")
	}

	opCode, p, err = rc.ReadMessage()
	if opCode != TextMessage || err != nil {
		t.Fatalf("ReadMessage() returned %d, p, %v", opCode, err)
	}

	if s := string(p); s != message {
		t.Fatalf("message is %s, want %s", s, message)
	}
}

// TestWriteBufferPoolSync ensures that *sync.Pool works as a buffer pool.
func TestWriteBufferPoolSync(t *testing.T) {
	var buf bytes.Buffer
	var pool sync.Pool
	wc := newConn(fakeNetConn{Writer: &buf}, true, 1024, 1024, &pool, nil, nil)
	rc := newTestConn(&buf, nil, false)

	const message = "Hello World!"
	for i := 0; i < 3; i++ {
		if err := wc.WriteMessage(TextMessage, []byte(message)); err != nil {
			t.Fatalf("wc.WriteMessage() returned %v", err)
		}
		opCode, p, err := rc.ReadMessage()
		if opCode != TextMessage || err != nil {
			t.Fatalf("ReadMessage() returned %d, p, %v", opCode, err)
		}
		if s := string(p); s != message {
			t.Fatalf("message is %s, want %s", s, message)
		}
	}
}

// errorWriter is an io.Writer than returns an error on all writes.
type errorWriter struct{}

func (ew errorWriter) Write(p []byte) (int, error) { return 0, errors.New("error") }

// TestWriteBufferPoolError ensures that buffer is returned to pool after error
// on write.
func TestWriteBufferPoolError(t *testing.T) {

	// Part 1: Test NextWriter/Write/Close

	var pool simpleBufferPool
	wc := newConn(fakeNetConn{Writer: errorWriter{}}, true, 1024, 1024, &pool, nil, nil)

	w, err := wc.NextWriter(TextMessage)
	if err != nil {
		t.Fatalf("wc.NextWriter() returned %v", err)
	}

	if wc.writeBuf == nil {
		t.Fatal("writeBuf is nil after NextWriter")
	}

	writeBufAddr := &wc.writeBuf[0]

	if _, err := io.WriteString(w, "Hello"); err != nil {
		t.Fatalf("io.WriteString(w, message) returned %v", err)
	}

	if err := w.Close(); err == nil {
		t.Fatalf("w.Close() did not return error")
	}

	if wpd, ok := pool.v.(writePoolData); !ok || len(wpd.buf) == 0 || &wpd.buf[0] != writeBufAddr {
		t.Fatal("writeBuf not returned to pool")
	}

	// Part 2: Test WriteMessage

	wc = newConn(fakeNetConn{Writer: errorWriter{}}, true, 1024, 1024, &pool, nil, nil)

	if err := wc.WriteMessage(TextMessage, []byte("Hello")); err == nil {
		t.Fatalf("wc.WriteMessage did not return error")
	}

	if wpd, ok := pool.v.(writePoolData); !ok || len(wpd.buf) == 0 || &wpd.buf[0] != writeBufAddr {
		t.Fatal("writeBuf not returned to pool")
	}
}

func TestCloseFrameBeforeFinalMessageFrame(t *testing.T) {
	const bufSize = 512

	expectedErr := &CloseError{Code: CloseNormalClosure, Text: "hello"}

	var b1, b2 bytes.Buffer
	wc := newConn(&fakeNetConn{Reader: nil, Writer: &b1}, false, 1024, bufSize, nil, nil, nil)
	rc := newTestConn(&b1, &b2, true)

	w, _ := wc.NextWriter(BinaryMessage)
	_, _ = w.Write(make([]byte, bufSize+bufSize/2))
	_ = wc.WriteControl(CloseMessage, FormatCloseMessage(expectedErr.Code, expectedErr.Text), time.Now().Add(10*time.Second))
	w.Close()

	op, r, err := rc.NextReader()
	if op != BinaryMessage || err != nil {
		t.Fatalf("NextReader() returned %d, %v", op, err)
	}
	_, err = io.Copy(io.Discard, r)
	if !reflect.DeepEqual(err, expectedErr) {
		t.Fatalf("io.Copy() returned %v, want %v", err, expectedErr)
	}
	_, _, err = rc.NextReader()
	if !reflect.DeepEqual(err, expectedErr) {
		t.Fatalf("NextReader() returned %v, want %v", err, expectedErr)
	}
}

func TestEOFWithinFrame(t *testing.T) {
	const bufSize = 64

	for n := 0; ; n++ {
		var b bytes.Buffer
		wc := newTestConn(nil, &b, false)
		rc := newTestConn(&b, nil, true)

		w, _ := wc.NextWriter(BinaryMessage)
		_, _ = w.Write(make([]byte, bufSize))
		w.Close()

		if n >= b.Len() {
			break
		}
		b.Truncate(n)

		op, r, err := rc.NextReader()
		if err == errUnexpectedEOF {
			continue
		}
		if op != BinaryMessage || err != nil {
			t.Fatalf("%d: NextReader() returned %d, %v", n, op, err)
		}
		_, err = io.Copy(io.Discard, r)
		if err != errUnexpectedEOF {
			t.Fatalf("%d: io.Copy() returned %v, want %v", n, err, errUnexpectedEOF)
		}
		_, _, err = rc.NextReader()
		if err != errUnexpectedEOF {
			t.Fatalf("%d: NextReader() returned %v, want %v", n, err, errUnexpectedEOF)
		}
	}
}

func TestEOFBeforeFinalFrame(t *testing.T) {
	const bufSize = 512

	var b1, b2 bytes.Buffer
	wc := newConn(&fakeNetConn{Writer: &b1}, false, 1024, bufSize, nil, nil, nil)
	rc := newTestConn(&b1, &b2, true)

	w, _ := wc.NextWriter(BinaryMessage)
	_, _ = w.Write(make([]byte, bufSize+bufSize/2))

	op, r, err := rc.NextReader()
	if op != BinaryMessage || err != nil {
		t.Fatalf("NextReader() returned %d, %v", op, err)
	}
	_, err = io.Copy(io.Discard, r)
	if err != errUnexpectedEOF {
		t.Fatalf("io.Copy() returned %v, want %v", err, errUnexpectedEOF)
	}
	_, _, err = rc.NextReader()
	if err != errUnexpectedEOF {
		t.Fatalf("NextReader() returned %v, want %v", err, errUnexpectedEOF)
	}
}

func TestWriteAfterMessageWriterClose(t *testing.T) {
	wc := newTestConn(nil, &bytes.Buffer{}, false)
	w, _ := wc.NextWriter(BinaryMessage)
	_, _ = io.WriteString(w, "hello")
	if err := w.Close(); err != nil {
		t.Fatalf("unexpected error closing message writer, %v", err)
	}

	if _, err := io.WriteString(w, "world"); err == nil {
		t.Fatalf("no error writing after close")
	}

	w, _ = wc.NextWriter(BinaryMessage)
	_, _ = io.WriteString(w, "hello")

	// close w by getting next writer
	_, err := wc.NextWriter(BinaryMessage)
	if err != nil {
		t.Fatalf("unexpected error getting next writer, %v", err)
	}

	if _, err := io.WriteString(w, "world"); err == nil {
		t.Fatalf("no error writing after close")
	}
}

func TestReadLimit(t *testing.T) {
	t.Run("Test ReadLimit is enforced", func(t *testing.T) {
		const readLimit = 512
		message := make([]byte, readLimit+1)

		var b1, b2 bytes.Buffer
		wc := newConn(&fakeNetConn{Writer: &b1}, false, 1024, readLimit-2, nil, nil, nil)
		rc := newTestConn(&b1, &b2, true)
		rc.SetReadLimit(readLimit)

		// Send message at the limit with interleaved pong.
		w, _ := wc.NextWriter(BinaryMessage)
		_, _ = w.Write(message[:readLimit-1])
		_ = wc.WriteControl(PongMessage, []byte("this is a pong"), time.Now().Add(10*time.Second))
		_, _ = w.Write(message[:1])
		w.Close()

		// Send message larger than the limit.
		_ = wc.WriteMessage(BinaryMessage, message[:readLimit+1])

		op, _, err := rc.NextReader()
		if op != BinaryMessage || err != nil {
			t.Fatalf("1: NextReader() returned %d, %v", op, err)
		}
		op, r, err := rc.NextReader()
		if op != BinaryMessage || err != nil {
			t.Fatalf("2: NextReader() returned %d, %v", op, err)
		}
		_, err = io.Copy(io.Discard, r)
		if err != ErrReadLimit {
			t.Fatalf("io.Copy() returned %v", err)
		}
	})

	t.Run("Test that ReadLimit cannot be overflowed", func(t *testing.T) {
		const readLimit = 1

		var b1, b2 bytes.Buffer
		rc := newTestConn(&b1, &b2, true)
		rc.SetReadLimit(readLimit)

		// First, send a non-final binary message
		b1.Write([]byte("\x02\x81"))

		// Mask key
		b1.Write([]byte("\x00\x00\x00\x00"))

		// First payload
		b1.Write([]byte("A"))

		// Next, send a negative-length, non-final continuation frame
		b1.Write([]byte("\x00\xFF\x80\x00\x00\x00\x00\x00\x00\x00"))

		// Mask key
		b1.Write([]byte("\x00\x00\x00\x00"))

		// Next, send a too long, final continuation frame
		b1.Write([]byte("\x80\xFF\x00\x00\x00\x00\x00\x00\x00\x05"))

		// Mask key
		b1.Write([]byte("\x00\x00\x00\x00"))

		// Too-long payload
		b1.Write([]byte("BCDEF"))

		op, r, err := rc.NextReader()
		if op != BinaryMessage || err != nil {
			t.Fatalf("1: NextReader() returned %d, %v", op, err)
		}

		var buf [10]byte
		var read int
		n, err := r.Read(buf[:])
		if err != nil && err != ErrReadLimit {
			t.Fatalf("unexpected error testing read limit: %v", err)
		}
		read += n

		n, err = r.Read(buf[:])
		if err != nil && err != ErrReadLimit {
			t.Fatalf("unexpected error testing read limit: %v", err)
		}
		read += n

		if err == nil && read > readLimit {
			t.Fatalf("read limit exceeded: limit %d, read %d", readLimit, read)
		}
	})
}

func TestAddrs(t *testing.T) {
	c := newTestConn(nil, nil, true)
	if c.LocalAddr() != localAddr {
		t.Errorf("LocalAddr = %v, want %v", c.LocalAddr(), localAddr)
	}
	if c.RemoteAddr() != remoteAddr {
		t.Errorf("RemoteAddr = %v, want %v", c.RemoteAddr(), remoteAddr)
	}
}

func TestNetConn(t *testing.T) {
	var b1, b2 bytes.Buffer
	fc := fakeNetConn{Reader: &b1, Writer: &b2}
	c := newConn(fc, true, 1024, 1024, nil, nil, nil)
	ul := c.NetConn()
	if ul != fc {
		t.Fatalf("Underlying conn is not what it should be.")
	}
}

func TestBufioReadBytes(t *testing.T) {
	// Test calling bufio.ReadBytes for value longer than read buffer size.

	m := make([]byte, 512)
	m[len(m)-1] = '\n'

	var b1, b2 bytes.Buffer
	wc := newConn(fakeNetConn{Writer: &b1}, false, len(m)+64, len(m)+64, nil, nil, nil)
	rc := newConn(fakeNetConn{Reader: &b1, Writer: &b2}, true, len(m)-64, len(m)-64, nil, nil, nil)

	w, _ := wc.NextWriter(BinaryMessage)
	_, _ = w.Write(m)
	w.Close()

	op, r, err := rc.NextReader()
	if op != BinaryMessage || err != nil {
		t.Fatalf("NextReader() returned %d, %v", op, err)
	}

	br := bufio.NewReader(r)
	p, err := br.ReadBytes('\n')
	if err != nil {
		t.Fatalf("ReadBytes() returned %v", err)
	}
	if len(p) != len(m) {
		t.Fatalf("read returned %d bytes, want %d bytes", len(p), len(m))
	}
}

var closeErrorTests = []struct {
	err   error
	codes []int
	ok    bool
}{
	{&CloseError{Code: CloseNormalClosure}, []int{CloseNormalClosure}, true},
	{&CloseError{Code: CloseNormalClosure}, []int{CloseNoStatusReceived}, false},
	{&CloseError{Code: CloseNormalClosure}, []int{CloseNoStatusReceived, CloseNormalClosure}, true},
	{errors.New("hello"), []int{CloseNormalClosure}, false},
}

func TestCloseError(t *testing.T) {
	for _, tt := range closeErrorTests {
		ok := IsCloseError(tt.err, tt.codes...)
		if ok != tt.ok {
			t.Errorf("IsCloseError(%#v, %#v) returned %v, want %v", tt.err, tt.codes, ok, tt.ok)
		}
	}
}

var unexpectedCloseErrorTests = []struct {
	err   error
	codes []int
	ok    bool
}{
	{&CloseError{Code: CloseNormalClosure}, []int{CloseNormalClosure}, false},
	{&CloseError{Code: CloseNormalClosure}, []int{CloseNoStatusReceived}, true},
	{&CloseError{Code: CloseNormalClosure}, []int{CloseNoStatusReceived, CloseNormalClosure}, false},
	{errors.New("hello"), []int{CloseNormalClosure}, false},
}

func TestUnexpectedCloseErrors(t *testing.T) {
	for _, tt := range unexpectedCloseErrorTests {
		ok := IsUnexpectedCloseError(tt.err, tt.codes...)
		if ok != tt.ok {
			t.Errorf("IsUnexpectedCloseError(%#v, %#v) returned %v, want %v", tt.err, tt.codes, ok, tt.ok)
		}
	}
}

type blockingWriter struct {
	c1, c2 chan struct{}
}

func (w blockingWriter) Write(p []byte) (int, error) {
	// Allow main to continue
	close(w.c1)
	// Wait for panic in main
	<-w.c2
	return len(p), nil
}

func TestConcurrentWritePanic(t *testing.T) {
	w := blockingWriter{make(chan struct{}), make(chan struct{})}
	c := newTestConn(nil, w, false)
	go func() {
		_ = c.WriteMessage(TextMessage, []byte{})
	}()

	// wait for goroutine to block in write.
	<-w.c1

	defer func() {
		close(w.c2)
		if v := recover(); v != nil {
			return
		}
	}()

	_ = c.WriteMessage(TextMessage, []byte{})
	t.Fatal("should not get here")
}

type failingReader struct{}

func (r failingReader) Read(p []byte) (int, error) {
	return 0, io.EOF
}

func TestFailedConnectionReadPanic(t *testing.T) {
	c := newTestConn(failingReader{}, nil, false)

	defer func() {
		if v := recover(); v != nil {
			return
		}
	}()

	for i := 0; i < 20000; i++ {
		_, _, _ = c.ReadMessage()
	}
	t.Fatal("should not get here")
}

func TestJoinMessages(t *testing.T) {
	messages := []string{"a", "bc", "def", "ghij", "klmno", "0", "12", "345", "6789"}
	for _, readChunk := range []int{1, 2, 3, 4, 5, 6, 7} {
		for _, term := range []string{"", ","} {
			var connBuf bytes.Buffer
			wc := newTestConn(nil, &connBuf, true)
			rc := newTestConn(&connBuf, nil, false)
			for _, m := range messages {
				_ = wc.WriteMessage(BinaryMessage, []byte(m))
			}

			var result bytes.Buffer
			_, err := io.CopyBuffer(&result, JoinMessages(rc, term), make([]byte, readChunk))
			if IsUnexpectedCloseError(err, CloseAbnormalClosure) {
				t.Errorf("readChunk=%d, term=%q: unexpected error %v", readChunk, term, err)
			}
			want := strings.Join(messages, term) + term
			if result.String() != want {
				t.Errorf("readChunk=%d, term=%q, got %q, want %q", readChunk, term, result.String(), want)
			}
		}
	}
}

func TestJSON(t *testing.T) {
	var buf bytes.Buffer
	wc := newTestConn(nil, &buf, true)
	rc := newTestConn(&buf, nil, false)

	var actual, expect struct {
		A int
		B string
	}
	expect.A = 1
	expect.B = "hello"

	if err := wc.WriteJSON(&expect); err != nil {
		t.Fatal("write", err)
	}

	if err := rc.ReadJSON(&actual); err != nil {
		t.Fatal("read", err)
	}

	if !reflect.DeepEqual(&actual, &expect) {
		t.Fatal("equal", actual, expect)
	}
}

func TestPartialJSONRead(t *testing.T) {
	var buf0, buf1 bytes.Buffer
	wc := newTestConn(nil, &buf0, true)
	rc := newTestConn(&buf0, &buf1, false)

	var v struct {
		A int
		B string
	}
	v.A = 1
	v.B = "hello"

	messageCount := 0

	// Partial JSON values.

	data, err := json.Marshal(v)
	if err != nil {
		t.Fatal(err)
	}
	for i := len(data) - 1; i >= 0; i-- {
		if err := wc.WriteMessage(TextMessage, data[:i]); err != nil {
			t.Fatal(err)
		}
		messageCount++
	}

	// Whitespace.

	if err := wc.WriteMessage(TextMessage, []byte(" ")); err != nil {
		t.Fatal(err)
	}
	messageCount++

	// Close.

	if err := wc.WriteMessage(CloseMessage, FormatCloseMessage(CloseNormalClosure, "")); err != nil {
		t.Fatal(err)
	}

	for i := 0; i < messageCount; i++ {
		err := rc.ReadJSON(&v)
		if err != io.ErrUnexpectedEOF {
			t.Error("read", i, err)
		}
	}

	err = rc.ReadJSON(&v)
	if _, ok := err.(*CloseError); !ok {
		t.Error("final", err)
	}
}

// !appengine

func maskBytesByByte(key [4]byte, pos int, b []byte) int {
	for i := range b {
		b[i] ^= key[pos&3]
		pos++
	}
	return pos & 3
}

func notzero(b []byte) int {
	for i := range b {
		if b[i] != 0 {
			return i
		}
	}
	return -1
}

func TestMaskBytes(t *testing.T) {
	key := [4]byte{1, 2, 3, 4}
	for size := 1; size <= 1024; size++ {
		for align := 0; align < wordSize; align++ {
			for pos := 0; pos < 4; pos++ {
				b := make([]byte, size+align)[align:]
				maskBytes(key, pos, b)
				maskBytesByByte(key, pos, b)
				if i := notzero(b); i >= 0 {
					t.Errorf("size:%d, align:%d, pos:%d, offset:%d", size, align, pos, i)
				}
			}
		}
	}
}

func BenchmarkMaskBytes(b *testing.B) {
	for _, size := range []int{2, 4, 8, 16, 32, 512, 1024} {
		b.Run(fmt.Sprintf("size-%d", size), func(b *testing.B) {
			for _, align := range []int{wordSize / 2} {
				b.Run(fmt.Sprintf("align-%d", align), func(b *testing.B) {
					for _, fn := range []struct {
						name string
						fn   func(key [4]byte, pos int, b []byte) int
					}{
						{"byte", maskBytesByByte},
						{"word", maskBytes},
					} {
						b.Run(fn.name, func(b *testing.B) {
							key := newMaskKey()
							data := make([]byte, size+align)[align:]
							for i := 0; i < b.N; i++ {
								fn.fn(key, 0, data)
							}
							b.SetBytes(int64(len(data)))
						})
					}
				})
			}
		})
	}
}

var preparedMessageTests = []struct {
	messageType            int
	isServer               bool
	enableWriteCompression bool
	compressionLevel       int
}{
	// Server
	{TextMessage, true, false, flate.BestSpeed},
	{TextMessage, true, true, flate.BestSpeed},
	{TextMessage, true, true, flate.BestCompression},
	{PingMessage, true, false, flate.BestSpeed},
	{PingMessage, true, true, flate.BestSpeed},

	// Client
	{TextMessage, false, false, flate.BestSpeed},
	{TextMessage, false, true, flate.BestSpeed},
	{TextMessage, false, true, flate.BestCompression},
	{PingMessage, false, false, flate.BestSpeed},
	{PingMessage, false, true, flate.BestSpeed},
}

func TestPreparedMessage(t *testing.T) {
	testRand := rand.New(rand.NewSource(99))
	prevMaskRand := maskRand
	maskRand = testRand
	defer func() { maskRand = prevMaskRand }()

	for _, tt := range preparedMessageTests {
		var data = []byte("this is a test")
		var buf bytes.Buffer
		c := newTestConn(nil, &buf, tt.isServer)
		if tt.enableWriteCompression {
			c.newCompressionWriter = compressNoContextTakeover
		}
		if err := c.SetCompressionLevel(tt.compressionLevel); err != nil {
			t.Fatal(err)
		}

		// Seed random number generator for consistent frame mask.
		testRand.Seed(1234)

		if err := c.WriteMessage(tt.messageType, data); err != nil {
			t.Fatal(err)
		}
		want := buf.String()

		pm, err := NewPreparedMessage(tt.messageType, data)
		if err != nil {
			t.Fatal(err)
		}

		// Scribble on data to ensure that NewPreparedMessage takes a snapshot.
		copy(data, "hello world")

		// Seed random number generator for consistent frame mask.
		testRand.Seed(1234)

		buf.Reset()
		if err := c.WritePreparedMessage(pm); err != nil {
			t.Fatal(err)
		}
		got := buf.String()

		if got != want {
			t.Errorf("write message != prepared message for %+v", tt)
		}
	}
}

var subprotocolTests = []struct {
	h         string
	protocols []string
}{
	{"", nil},
	{"foo", []string{"foo"}},
	{"foo,bar", []string{"foo", "bar"}},
	{"foo, bar", []string{"foo", "bar"}},
	{" foo, bar", []string{"foo", "bar"}},
	{" foo, bar ", []string{"foo", "bar"}},
}

func TestSubprotocols(t *testing.T) {
	for _, st := range subprotocolTests {
		r := http.Request{Header: http.Header{"Sec-Websocket-Protocol": {st.h}}}
		protocols := Subprotocols(&r)
		if !reflect.DeepEqual(st.protocols, protocols) {
			t.Errorf("SubProtocols(%q) returned %#v, want %#v", st.h, protocols, st.protocols)
		}
	}
}

var isWebSocketUpgradeTests = []struct {
	ok bool
	h  http.Header
}{
	{false, http.Header{"Upgrade": {"websocket"}}},
	{false, http.Header{"Connection": {"upgrade"}}},
	{true, http.Header{"Connection": {"upgRade"}, "Upgrade": {"WebSocket"}}},
}

func TestIsWebSocketUpgrade(t *testing.T) {
	for _, tt := range isWebSocketUpgradeTests {
		ok := IsWebSocketUpgrade(&http.Request{Header: tt.h})
		if tt.ok != ok {
			t.Errorf("IsWebSocketUpgrade(%v) returned %v, want %v", tt.h, ok, tt.ok)
		}
	}
}

func TestSubProtocolSelection(t *testing.T) {
	upgrader := Upgrader{
		Subprotocols: []string{"foo", "bar", "baz"},
	}

	r := http.Request{Header: http.Header{"Sec-Websocket-Protocol": {"foo", "bar"}}}
	s := upgrader.selectSubprotocol(&r, nil)
	if s != "foo" {
		t.Errorf("Upgrader.selectSubprotocol returned %v, want %v", s, "foo")
	}

	r = http.Request{Header: http.Header{"Sec-Websocket-Protocol": {"bar", "foo"}}}
	s = upgrader.selectSubprotocol(&r, nil)
	if s != "bar" {
		t.Errorf("Upgrader.selectSubprotocol returned %v, want %v", s, "bar")
	}

	r = http.Request{Header: http.Header{"Sec-Websocket-Protocol": {"baz"}}}
	s = upgrader.selectSubprotocol(&r, nil)
	if s != "baz" {
		t.Errorf("Upgrader.selectSubprotocol returned %v, want %v", s, "baz")
	}

	r = http.Request{Header: http.Header{"Sec-Websocket-Protocol": {"quux"}}}
	s = upgrader.selectSubprotocol(&r, nil)
	if s != "" {
		t.Errorf("Upgrader.selectSubprotocol returned %v, want %v", s, "empty string")
	}
}

var checkSameOriginTests = []struct {
	ok bool
	r  *http.Request
}{
	{false, &http.Request{Host: "example.org", Header: map[string][]string{"Origin": {"https://other.org"}}}},
	{true, &http.Request{Host: "example.org", Header: map[string][]string{"Origin": {"https://example.org"}}}},
	{true, &http.Request{Host: "Example.org", Header: map[string][]string{"Origin": {"https://example.org"}}}},
}

func TestCheckSameOrigin(t *testing.T) {
	for _, tt := range checkSameOriginTests {
		ok := checkSameOrigin(tt.r)
		if tt.ok != ok {
			t.Errorf("checkSameOrigin(%+v) returned %v, want %v", tt.r, ok, tt.ok)
		}
	}
}

type reuseTestResponseWriter struct {
	brw *bufio.ReadWriter
	http.ResponseWriter
}

func (resp *reuseTestResponseWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
	return fakeNetConn{strings.NewReader(""), &bytes.Buffer{}}, resp.brw, nil
}

var bufioReuseTests = []struct {
	n     int
	reuse bool
}{
	{4096, true},
	{128, false},
}

func xTestBufioReuse(t *testing.T) {
	for i, tt := range bufioReuseTests {
		br := bufio.NewReaderSize(strings.NewReader(""), tt.n)
		bw := bufio.NewWriterSize(&bytes.Buffer{}, tt.n)
		resp := &reuseTestResponseWriter{
			brw: bufio.NewReadWriter(br, bw),
		}
		upgrader := Upgrader{}
		c, err := upgrader.Upgrade(resp, &http.Request{
			Method: http.MethodGet,
			Header: http.Header{
				"Upgrade":               []string{"websocket"},
				"Connection":            []string{"upgrade"},
				"Sec-Websocket-Key":     []string{"dGhlIHNhbXBsZSBub25jZQ=="},
				"Sec-Websocket-Version": []string{"13"},
			}}, nil)
		if err != nil {
			t.Fatal(err)
		}
		if reuse := c.br == br; reuse != tt.reuse {
			t.Errorf("%d: buffered reader reuse=%v, want %v", i, reuse, tt.reuse)
		}
		writeBuf := bw.AvailableBuffer()
		if reuse := &c.writeBuf[0] == &writeBuf[0]; reuse != tt.reuse {
			t.Errorf("%d: write buffer reuse=%v, want %v", i, reuse, tt.reuse)
		}
	}
}

func TestHijack_NotSupported(t *testing.T) {
	t.Parallel()

	req := httptest.NewRequest(http.MethodGet, "http://example.com", nil)
	req.Header.Set("Upgrade", "websocket")
	req.Header.Set("Connection", "upgrade")
	req.Header.Set("Sec-Websocket-Key", "dGhlIHNhbXBsZSBub25jZQ==")
	req.Header.Set("Sec-Websocket-Version", "13")

	recorder := httptest.NewRecorder()

	upgrader := Upgrader{}
	_, err := upgrader.Upgrade(recorder, req, nil)

	if want := (HandshakeError{}); !errors.As(err, &want) || recorder.Code != http.StatusInternalServerError {
		t.Errorf("want %T and status_code=%d", want, http.StatusInternalServerError)
		t.Fatalf("got err=%T and status_code=%d", err, recorder.Code)
	}
}

var equalASCIIFoldTests = []struct {
	t, s string
	eq   bool
}{
	{"WebSocket", "websocket", true},
	{"websocket", "WebSocket", true},
	{"Öyster", "öyster", false},
	{"WebSocket", "WetSocket", false},
}

func TestEqualASCIIFold(t *testing.T) {
	for _, tt := range equalASCIIFoldTests {
		eq := equalASCIIFold(tt.s, tt.t)
		if eq != tt.eq {
			t.Errorf("equalASCIIFold(%q, %q) = %v, want %v", tt.s, tt.t, eq, tt.eq)
		}
	}
}

var tokenListContainsValueTests = []struct {
	value string
	ok    bool
}{
	{"WebSocket", true},
	{"WEBSOCKET", true},
	{"websocket", true},
	{"websockets", false},
	{"x websocket", false},
	{"websocket x", false},
	{"other,websocket,more", true},
	{"other, websocket, more", true},
}

func TestTokenListContainsValue(t *testing.T) {
	for _, tt := range tokenListContainsValueTests {
		h := http.Header{"Upgrade": {tt.value}}
		ok := tokenListContainsValue(h, "Upgrade", "websocket")
		if ok != tt.ok {
			t.Errorf("tokenListContainsValue(h, n, %q) = %v, want %v", tt.value, ok, tt.ok)
		}
	}
}

var isValidChallengeKeyTests = []struct {
	key string
	ok  bool
}{
	{"dGhlIHNhbXBsZSBub25jZQ==", true},
	{"", false},
	{"InvalidKey", false},
	{"WHQ4eXhscUtKYjBvOGN3WEdtOEQ=", false},
}

func TestIsValidChallengeKey(t *testing.T) {
	for _, tt := range isValidChallengeKeyTests {
		ok := isValidChallengeKey(tt.key)
		if ok != tt.ok {
			t.Errorf("isValidChallengeKey returns %v, want %v", ok, tt.ok)
		}
	}
}

var parseExtensionTests = []struct {
	value      string
	extensions []map[string]string
}{
	{`foo`, []map[string]string{{"": "foo"}}},
	{`foo, bar; baz=2`, []map[string]string{
		{"": "foo"},
		{"": "bar", "baz": "2"}}},
	{`foo; bar="b,a;z"`, []map[string]string{
		{"": "foo", "bar": "b,a;z"}}},
	{`foo , bar; baz = 2`, []map[string]string{
		{"": "foo"},
		{"": "bar", "baz": "2"}}},
	{`foo, bar; baz=2 junk`, []map[string]string{
		{"": "foo"}}},
	{`foo junk, bar; baz=2 junk`, nil},
	{`mux; max-channels=4; flow-control, deflate-stream`, []map[string]string{
		{"": "mux", "max-channels": "4", "flow-control": ""},
		{"": "deflate-stream"}}},
	{`permessage-foo; x="10"`, []map[string]string{
		{"": "permessage-foo", "x": "10"}}},
	{`permessage-foo; use_y, permessage-foo`, []map[string]string{
		{"": "permessage-foo", "use_y": ""},
		{"": "permessage-foo"}}},
	{`permessage-deflate; client_max_window_bits; server_max_window_bits=10 , permessage-deflate; client_max_window_bits`, []map[string]string{
		{"": "permessage-deflate", "client_max_window_bits": "", "server_max_window_bits": "10"},
		{"": "permessage-deflate", "client_max_window_bits": ""}}},
	{"permessage-deflate; server_no_context_takeover; client_max_window_bits=15", []map[string]string{
		{"": "permessage-deflate", "server_no_context_takeover": "", "client_max_window_bits": "15"},
	}},
}

func TestParseExtensions(t *testing.T) {
	for _, tt := range parseExtensionTests {
		h := http.Header{http.CanonicalHeaderKey("Sec-WebSocket-Extensions"): {tt.value}}
		extensions := parseExtensions(h)
		if !reflect.DeepEqual(extensions, tt.extensions) {
			t.Errorf("parseExtensions(%q)\n    = %v,\nwant %v", tt.value, extensions, tt.extensions)
		}
	}
}

func test_parseArgs() {
	given := parseArgs([]string { "x", "y", "z" })
	expected := _CLIArgs {
		fromAddr: "y",
		toAddr:   "z",
	}

	g.AssertEqual(given, expected)
}



func MainTest() {
	test_parseArgs()


	tests := []testing.InternalTest {
		{ "TestBadMethod", TestBadMethod },
		{ "TestNoUpgrade", TestNoUpgrade },
		{ "TestHostPortNoPort", TestHostPortNoPort },
		{ "TestTruncWriter", TestTruncWriter },
		{ "TestValidCompressionLevel", TestValidCompressionLevel },
		{ "TestFraming", TestFraming },
		{ "TestWriteControlDeadline", TestWriteControlDeadline },
		{ "TestConcurrencyWriteControl", TestConcurrencyWriteControl },
		{ "TestControl", TestControl },
		{ "TestWriteBufferPool", TestWriteBufferPool },
		{ "TestWriteBufferPoolSync", TestWriteBufferPoolSync },
		{ "TestWriteBufferPoolError", TestWriteBufferPoolError },
		{ "TestCloseFrameBeforeFinalMessageFrame", TestCloseFrameBeforeFinalMessageFrame },
		{ "TestEOFWithinFrame", TestEOFWithinFrame },
		{ "TestEOFBeforeFinalFrame", TestEOFBeforeFinalFrame },
		{ "TestWriteAfterMessageWriterClose", TestWriteAfterMessageWriterClose },
		{ "TestReadLimit", TestReadLimit },
		{ "TestAddrs", TestAddrs },
		{ "TestNetConn", TestNetConn },
		{ "TestBufioReadBytes", TestBufioReadBytes },
		{ "TestCloseError", TestCloseError },
		{ "TestUnexpectedCloseErrors", TestUnexpectedCloseErrors },
		{ "TestConcurrentWritePanic", TestConcurrentWritePanic },
		{ "TestFailedConnectionReadPanic", TestFailedConnectionReadPanic },
		{ "TestJoinMessages", TestJoinMessages },
		{ "TestJSON", TestJSON },
		{ "TestPartialJSONRead", TestPartialJSONRead },
		{ "TestMaskBytes", TestMaskBytes },
		{ "TestPreparedMessage", TestPreparedMessage },
		{ "TestSubprotocols", TestSubprotocols },
		{ "TestIsWebSocketUpgrade", TestIsWebSocketUpgrade },
		{ "TestSubProtocolSelection", TestSubProtocolSelection },
		{ "TestCheckSameOrigin", TestCheckSameOrigin },
		{ "TestHijack_NotSupported", TestHijack_NotSupported },
		{ "TestEqualASCIIFold", TestEqualASCIIFold },
		{ "TestTokenListContainsValue", TestTokenListContainsValue },
		{ "TestIsValidChallengeKey", TestIsValidChallengeKey },
		{ "TestParseExtensions", TestParseExtensions },
	}

	benchmarks  := []testing.InternalBenchmark  {
		{ "BenchmarkWriteNoCompression", BenchmarkWriteNoCompression },
		{ "BenchmarkWriteWithCompression", BenchmarkWriteWithCompression },
		{ "BenchmarkBroadcast", BenchmarkBroadcast },
		{ "BenchmarkMaskBytes", BenchmarkMaskBytes },
	}

	fuzzTargets := []testing.InternalFuzzTarget {}
	examples    := []testing.InternalExample    {}
	m := testing.MainStart(
		testdeps.TestDeps {},
		tests,
		benchmarks,
		fuzzTargets,
		examples,
	)
	os.Exit(m.Run())
}