fix: solve issue with Antenna Genius for remote operations

internal/cat/icomserial.go

@@ -12,18 +12,38 @@ import (
 	"go.bug.st/serial"
 )
 
-// IcomSerial controls an Icom transceiver over its USB/serial CI-V port (local
-// control). It speaks the shared civ protocol, so when the network backend
-// (icomnet) is added it will reuse the same encode/decode — only the transport
-// changes. Implements Backend; all methods run on the Manager's CAT goroutine,
-// so the port is accessed single-threaded (no locking needed).
+// civTransport is everything IcomSerial needs from its underlying link. It's
+// satisfied directly by a go.bug.st serial.Port (USB, local control) and, for
+// remote control, by the icomnet UDP stream which presents the tunnelled CI-V
+// byte stream as plain Read/Write (there SetDTR/SetRTS/SetReadTimeout are
+// no-ops). Abstracting it here means the whole IcomController surface — DSP,
+// scope, RIT, CW — is reused unchanged over the network; only `open` differs.
+type civTransport interface {
+	Read(p []byte) (int, error)
+	Write(p []byte) (int, error)
+	Close() error
+	SetReadTimeout(time.Duration) error
+	SetDTR(bool) error
+	SetRTS(bool) error
+}
+
+// IcomSerial controls an Icom transceiver over the shared civ protocol. The
+// transport is pluggable via `open`: NewIcomSerial opens a USB/serial port;
+// NewIcomNet (later) returns one configured with a network transport. Implements
+// Backend; all methods run on the Manager's CAT goroutine, so the port is
+// accessed single-threaded (no locking needed).
 type IcomSerial struct {
 	portName string
 	baud     int
 	rigAddr  byte   // rig's CI-V address (IC-7610 default 0x98)
 	digital  string // mode to command for DATA (FT8/RTTY/…)
 
-	port  serial.Port
+	// open dials the underlying link (serial port or network stream). Set by the
+	// constructor; called by Connect. Blocks until connected (the network opener
+	// performs the full UDP handshake + login before returning).
+	open func() (civTransport, error)
+
+	port  civTransport
 	model string
 
 	// I/O routing. A single reader goroutine owns port.Read and dispatches every
@@ -82,7 +102,7 @@ func NewIcomSerial(portName string, baud, civAddr int, digitalDefault string) *I
 	if digitalDefault == "" {
 		digitalDefault = "FT8"
 	}
-	return &IcomSerial{
+	b := &IcomSerial{
 		portName:   portName,
 		baud:       baud,
 		rigAddr:    byte(civAddr),
@@ -90,20 +110,32 @@ func NewIcomSerial(portName string, baud, civAddr int, digitalDefault string) *I
 		model:      "Icom",
 		scopeFixed: true, // rigs default to a fixed-span scope
 	}
+	// USB/serial transport opener.
+	b.open = func() (civTransport, error) {
+		if b.portName == "" {
+			return nil, fmt.Errorf("no serial port configured")
+		}
+		p, err := serial.Open(b.portName, &serial.Mode{BaudRate: b.baud})
+		if err != nil {
+			return nil, fmt.Errorf("open %s @ %d baud: %w", b.portName, b.baud, err)
+		}
+		return p, nil
+	}
+	return b
 }
 
 func (b *IcomSerial) Name() string { return "icom" }
 
 func (b *IcomSerial) Connect() error {
-	if b.portName == "" {
-		return fmt.Errorf("no serial port configured")
+	if b.open == nil {
+		return fmt.Errorf("no transport configured")
 	}
-	port, err := serial.Open(b.portName, &serial.Mode{BaudRate: b.baud})
+	port, err := b.open()
 	if err != nil {
-		return fmt.Errorf("open %s @ %d baud: %w", b.portName, b.baud, err)
+		return err
 	}
 	// Short read timeout so recv() polls in a tight loop without blocking the
-	// CAT goroutine when the rig is silent.
+	// CAT goroutine when the rig is silent. (No-op on the network transport.)
 	_ = port.SetReadTimeout(60 * time.Millisecond)
 	// Deassert DTR/RTS. Icom USB rigs (IC-7610, IC-7300…) let "USB SEND" and
 	// "USB Keying (CW)" be mapped to the RTS or DTR line: if the port opens with
@@ -312,7 +344,7 @@ func (b *IcomSerial) recv(timeout time.Duration, match func(civ.Decoded) bool) (
 // frames and routes each: our own echoes are dropped, spectrum-scope frames
 // (0x27) go to specCh, everything else (control replies, acks, unsolicited
 // transceive updates) goes to respCh. It exits when the port is closed.
-func (b *IcomSerial) reader(port serial.Port, done chan struct{}) {
+func (b *IcomSerial) reader(port civTransport, done chan struct{}) {
 	defer close(done)
 	tmp := make([]byte, 512)
 	var rx []byte