feat: overhauled gateway

1 files changed, 78 insertions, 76 deletions

diff --git a/internal/client/gateway/gateway.go b/internal/client/gateway/gateway.go
index 56f1ade..7e9ab82 100644
--- a/internal/client/gateway/gateway.go
+++ b/internal/client/gateway/gateway.go
@@ -6,11 +6,8 @@ import (
 	"crypto/tls"
 	"crypto/x509"
 	_ "embed"
-	"errors"
-	"io"
 	"log"
 	"net"
-	"os"
 	"sync"
 	"time"
 
@@ -29,8 +26,9 @@ var (
 	asyncResponses []chan packet.Payload
 	responsesMu    sync.Mutex
 
-	connection net.Conn
-	connMu     sync.Mutex
+	framer  packet.PacketFramer
+	conn    net.Conn
+	writeMu sync.Mutex
 )
 
 func init() {
@@ -45,41 +43,68 @@ func init() {
 	}
 }
 
-func Connect(ctx context.Context, program *tea.Program, privKey ed25519.PrivateKey) {
-	conn, err := tls.Dial("tcp4", ":7223", tlsConfig)
-	if err != nil {
-		assert.NoError(err, "TODO handle error")
-	}
-	log.Println("established connection with server")
+func Connect(ctx context.Context, program *tea.Program, privKey ed25519.PrivateKey) error {
+	assert.Assert(conn == nil, "cannot connect, connection is active")
+
+	connChan := make(chan net.Conn, 1)
+	errChan := make(chan error, 1)
+	go func() {
+		framer = packet.NewFramer()
+		connection, err := tls.Dial("tcp4", ":7223", tlsConfig)
+		if err != nil {
+			errChan <- err
+			return
+		}
+		log.Println("established connection with server")
+
+		if err := handleAuth(ctx, privKey); err != nil {
+			errChan <- err
+			return
+		}
+		log.Println("successfully authenticated with server")
+		connChan <- connection
+	}()
 
-	if err := handleAuth(ctx, conn, privKey); err != nil {
-		assert.NoError(err, "TODO handle error")
+	select {
+	case connection := <-connChan:
+		conn = connection
+	case err := <-errChan:
+		return err
+	case <-ctx.Done():
+		return ctx.Err()
 	}
-	log.Println("successfully authenticated with server")
 
-	framer := packet.NewFramer()
+	go readUntilDisconnected()
+	go handlePacketStream(program)
 
-	go func() {
-		connection = conn
-		handleConnection(ctx, conn, framer)
-		close(framer.Out)
-		conn.Close()
-		connection = nil
-	}()
+	return nil
+}
 
-	go handlePacketStream(framer, program)
+func Disconnect() {
+	assert.Assert(conn != nil, "cannot disconnect, connection is inactive")
+	close(framer.Out)
+	conn.Close()
+	conn = nil
+	responsesMu.Lock()
+	for _, responseChan := range asyncResponses {
+		close(responseChan)
+	}
+	asyncResponses = nil
+	responsesMu.Unlock()
 }
 
-func handleAuth(ctx context.Context, conn net.Conn, privKey ed25519.PrivateKey) error {
+func handleAuth(ctx context.Context, privKey ed25519.PrivateKey) error {
 	const nonceSize = 32
 	challengeRequest := make([]byte, 1+nonceSize)
 
-	err := conn.SetDeadline(time.Now().Add(10 * time.Second))
+	deadline, _ := ctx.Deadline()
+	err := conn.SetDeadline(deadline)
 	assert.NoError(err, "setting deadline should not error")
 	defer func() {
 		err := conn.SetDeadline(time.Time{})
 		assert.NoError(err, "unsetting deadline should not error")
 	}()
+
 	bytesRead := 0
 	for bytesRead < 1+nonceSize {
 		n, err := conn.Read(challengeRequest[bytesRead:])
@@ -106,35 +131,41 @@ func handleAuth(ctx context.Context, conn net.Conn, privKey ed25519.PrivateKey)
 	return nil
 }
 
-func handleConnection(ctx context.Context, conn net.Conn, framer packet.PacketFramer) {
-	buffer := make([]byte, 512)
-	for {
-		err := conn.SetReadDeadline(time.Now().Add(time.Second))
-		assert.NoError(err, "setting a read deadline should not error")
-		n, err := conn.Read(buffer)
-		deadlineExceeded := errors.Is(err, os.ErrDeadlineExceeded)
-		if err != nil && !deadlineExceeded {
-			if !errors.Is(err, io.EOF) {
-				log.Println("read error:", err)
+func readUntilDisconnected() {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go func() {
+		for {
+			select {
+			case <-ctx.Done():
+				return
+			default:
+				if conn == nil {
+					cancel()
+					return
+				}
 			}
-			break
 		}
+	}()
 
-		if ctx.Err() != nil {
-			log.Println("context error:", ctx.Err())
+	buffer := make([]byte, 512)
+	for conn != nil {
+		n, err := conn.Read(buffer)
+		if err != nil {
+			log.Println("server connectivity error: ", err)
 			break
 		}
 
 		err = framer.Push(ctx, buffer[:n])
 		if ctx.Err() != nil {
-			log.Println("context error:", ctx.Err())
+			log.Println("server connectivity error: ", ctx.Err())
 			break
 		}
-		assert.NoError(err, "packets from server should always be correct")
+		assert.NoError(err, "packets from server should always be correctly formatted")
 	}
 }
 
-func handlePacketStream(framer packet.PacketFramer, program *tea.Program) {
+func handlePacketStream(program *tea.Program) {
 	for {
 		pkt, ok := <-framer.Out
 		if !ok {
@@ -163,58 +194,29 @@ func handlePacketStream(framer packet.PacketFramer, program *tea.Program) {
 	}
 }
 
-func conn() net.Conn {
-	return connection
-}
-
 func Send(request packet.Payload) <-chan packet.Payload {
 	responseChan := make(chan packet.Payload)
 	go func() {
 		pkt := packet.NewPacket(packet.NewMsgPackEncoder(request))
 
-		conn := conn()
+		responsesMu.Lock()
+		asyncResponses = append(asyncResponses, responseChan)
+		responsesMu.Unlock()
+
 		if conn == nil {
 			log.Println("request send error:", "connection is closed")
 			close(responseChan)
 			return
 		}
 
-		connMu.Lock()
-		errDeadline := conn.SetWriteDeadline(time.Now().Add(5 * time.Second))
-		assert.NoError(errDeadline, "setting a write deadline should not error")
+		writeMu.Lock()
 		_, err := pkt.Into(conn)
-		errDeadline = conn.SetWriteDeadline(time.Time{})
-		assert.NoError(errDeadline, "setting a write deadline should not error")
-		connMu.Unlock()
+		writeMu.Unlock()
 		if err != nil {
 			log.Println("request send error:", err)
 			close(responseChan)
 			return
 		}
-
-		responsesMu.Lock()
-		asyncResponses = append(asyncResponses, responseChan)
-		responsesMu.Unlock()
-
-		// TODO: this is a really bad implementation
-		// Should refactor to make it better
-		// Maybe have a timeout function similar to the one on the server?
-		// In any case this is like super bad to just arbitrary hang for 5 seconds
-		// And then try to close the thing so it times out
-		time.Sleep(5 * time.Second)
-		responsesMu.Lock()
-		index := -1
-		for i, ch := range asyncResponses {
-			if ch == responseChan {
-				index = i
-			}
-		}
-		if index != -1 {
-			copy(asyncResponses[index:], asyncResponses[index+1:])
-			asyncResponses = asyncResponses[:len(asyncResponses)-1]
-			close(responseChan)
-		}
-		responsesMu.Unlock()
 	}()
 	return responseChan
 }