fix: Save and close taking time when Flex or Icom is not connected

internal/cat/tci.go

@@ -3,6 +3,7 @@
 package cat
 
 import (
+	"context"
 	"fmt"
 	"net"
 	"strconv"
@@ -27,9 +28,10 @@ type TCI struct {
 	digitalDefault string // surfaced when the rig reports a digital mode (FT8/…)
 	spotsEnabled   bool   // mirror cluster spots onto the TCI panorama
 
-	mu    sync.Mutex // guards conn + writes + state
-	conn  *websocket.Conn
-	ready bool
+	mu         sync.Mutex // guards conn + writes + state
+	conn       *websocket.Conn
+	dialCancel context.CancelFunc // cancels an in-flight Connect dial (Interrupt/Stop)
+	ready      bool
 
 	// Cached state pushed by the radio.
 	device string
@@ -70,8 +72,18 @@ func (t *TCI) Connect() error {
 		return fmt.Errorf("tci: no host configured")
 	}
 	url := fmt.Sprintf("ws://%s", net.JoinHostPort(host, strconv.Itoa(port)))
+	// Cancellable dial so Interrupt() (Stop / Settings "Save & Close") aborts it at
+	// once instead of waiting out a dead server's 5 s handshake timeout.
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	t.mu.Lock()
+	t.dialCancel = cancel
+	t.mu.Unlock()
 	dialer := websocket.Dialer{HandshakeTimeout: 5 * time.Second}
-	conn, _, err := dialer.Dial(url, nil)
+	conn, _, err := dialer.DialContext(ctx, url, nil)
+	cancel()
+	t.mu.Lock()
+	t.dialCancel = nil
+	t.mu.Unlock()
 	if err != nil {
 		return fmt.Errorf("tci: connect %s: %w", url, err)
 	}
@@ -122,6 +134,22 @@ func (t *TCI) Disconnect() {
 	}
 }
 
+// Interrupt aborts an in-flight Connect dial so Stop()/Start() don't block on a
+// dead server's handshake timeout. Satisfies the Manager's interruptible
+// interface. Safe from another goroutine; a no-op when not dialing.
+func (t *TCI) Interrupt() {
+	t.mu.Lock()
+	cancel := t.dialCancel
+	c := t.conn
+	t.mu.Unlock()
+	if cancel != nil {
+		cancel()
+	}
+	if c != nil {
+		_ = c.Close()
+	}
+}
+
 // ReadState returns the cached state pushed by the radio.
 func (t *TCI) ReadState() (RigState, error) {
 	t.mu.Lock()