refactor(tracker): use strings to identify MIDI ports

cmd/sointu-track/main.go

@@ -20,8 +20,7 @@ import (
 
 var cpuprofile = flag.String("cpuprofile", "", "write cpu profile to `file`")
 var memprofile = flag.String("memprofile", "", "write memory profile to `file`")
-var defaultMidiInput = flag.String("midi-input", "", "connect MIDI input to matching device name")
-var firstMidiInput = flag.Bool("first-midi-input", false, "connect MIDI input to first device found")
+var defaultMidiInput = flag.String("midi-input", "", "connect MIDI input to matching device name prefix")
 
 func main() {
 	flag.Parse()
@@ -48,7 +47,17 @@ func main() {
 	broker := tracker.NewBroker()
 	midiContext := cmd.NewMidiContext(broker)
 	defer midiContext.Close()
-	midiContext.TryToOpenBy(*defaultMidiInput, *firstMidiInput)
+	if isFlagPassed("midi-input") {
+		input, ok := tracker.FindMIDIDeviceByPrefix(midiContext, *defaultMidiInput)
+		if ok {
+			err := midiContext.Open(input)
+			if err != nil {
+				log.Printf("failed to open MIDI input '%s': %v", input, err)
+			}
+		} else {
+			log.Printf("no MIDI input device found with prefix '%s'", *defaultMidiInput)
+		}
+	}
 	model := tracker.NewModel(broker, cmd.Synthers, midiContext, recoveryFile)
 	player := tracker.NewPlayer(broker, cmd.Synthers[0])
 	detector := tracker.NewDetector(broker)
@@ -96,3 +105,13 @@ func main() {
 	}()
 	app.Main()
 }
+
+func isFlagPassed(name string) bool {
+	found := false
+	flag.Visit(func(f *flag.Flag) {
+		if f.Name == name {
+			found = true
+		}
+	})
+	return found
+}

tracker/action.go

@@ -620,16 +620,16 @@ func (m *Model) ShowLicense() Action { return MakeAction((*showLicense)(m)) }
 func (m *showLicense) Do()           { m.dialog = License }
 
 type selectMidiInput struct {
-	Item MIDIDevice
+	Item string
 	*Model
 }
 
-func (m *Model) SelectMidiInput(item MIDIDevice) Action {
+func (m *Model) SelectMidiInput(item string) Action {
 	return MakeAction(selectMidiInput{Item: item, Model: m})
 }
 func (s selectMidiInput) Do() {
 	m := s.Model
-	if err := s.Item.Open(); err == nil {
+	if err := s.Model.MIDI.Open(s.Item); err == nil {
 		message := fmt.Sprintf("Opened MIDI device: %s", s.Item)
 		m.Alerts().Add(message, Info)
 	} else {

tracker/gioui/song_panel.go

@@ -480,7 +480,7 @@ func NewMenuBar(tr *Tracker) *MenuBar {
 	}
 	for input := range tr.MIDI.InputDevices {
 		ret.midiMenuItems = append(ret.midiMenuItems,
-			MenuItem(tr.SelectMidiInput(input), input.String(), "", icons.ImageControlPoint),
+			MenuItem(tr.SelectMidiInput(input), input, "", icons.ImageControlPoint),
 		)
 	}
 	return ret

tracker/gomidi/midi.go

@@ -9,7 +9,6 @@ import "C"
 import (
 	"errors"
 	"fmt"
-	"strings"
 
 	"github.com/vsariola/sointu/tracker"
 	"gitlab.com/gomidi/midi/v2"
@@ -23,14 +22,9 @@ type (
 		currentIn drivers.In
 		broker    *tracker.Broker
 	}
-
-	RTMIDIDevice struct {
-		context *RTMIDIContext
-		in      drivers.In
-	}
 )
 
-func (m *RTMIDIContext) InputDevices(yield func(tracker.MIDIDevice) bool) {
+func (m *RTMIDIContext) InputDevices(yield func(string) bool) {
 	if m.driver == nil {
 		return
 	}
@@ -38,9 +32,8 @@ func (m *RTMIDIContext) InputDevices(yield func(tracker.MIDIDevice) bool) {
 	if err != nil {
 		return
 	}
-	for i := 0; i < len(ins); i++ {
-		device := RTMIDIDevice{context: m, in: ins[i]}
-		if !yield(device) {
+	for _, in := range ins {
+		if !yield(in.String()) {
 			break
 		}
 	}
@@ -56,34 +49,43 @@ func NewContext(broker *tracker.Broker) *RTMIDIContext {
 }
 
 // Open an input device while closing the currently open if necessary.
-func (m RTMIDIDevice) Open() error {
-	if m.context.currentIn == m.in {
+func (m *RTMIDIContext) Open(name string) error {
+	if m.currentIn != nil && m.currentIn.String() == name {
 		return nil
 	}
-	if m.context.driver == nil {
+	if m.driver == nil {
 		return errors.New("no driver available")
 	}
-	if m.context.HasDeviceOpen() {
-		m.context.currentIn.Close()
+	if m.IsOpen() {
+		m.currentIn.Close()
 	}
-	m.context.currentIn = m.in
-	err := m.in.Open()
+	m.currentIn = nil
+	ins, err := m.driver.Ins()
 	if err != nil {
-		m.context.currentIn = nil
-		return fmt.Errorf("opening MIDI input failed: %W", err)
+		return fmt.Errorf("retrieving MIDI inputs failed: %w", err)
 	}
-	_, err = midi.ListenTo(m.in, m.context.HandleMessage)
+	for _, in := range ins {
+		if in.String() == name {
+			m.currentIn = in
+		}
+	}
+	if m.currentIn == nil {
+		return fmt.Errorf("MIDI input device not found: %s", name)
+	}
+	err = m.currentIn.Open()
 	if err != nil {
-		m.in.Close()
-		m.context.currentIn = nil
+		m.currentIn = nil
+		return fmt.Errorf("opening MIDI input failed: %w", err)
+	}
+	_, err = midi.ListenTo(m.currentIn, m.HandleMessage)
+	if err != nil {
+		m.currentIn.Close()
+		m.currentIn = nil
+		return fmt.Errorf("listening to MIDI input failed: %w", err)
 	}
 	return nil
 }
 
-func (d RTMIDIDevice) String() string {
-	return d.in.String()
-}
-
 func (m *RTMIDIContext) HandleMessage(msg midi.Message, timestampms int32) {
 	var channel, key, velocity uint8
 	if msg.GetNoteOn(&channel, &key, &velocity) {
@@ -109,23 +111,6 @@ func (c *RTMIDIContext) Close() {
 	c.driver.Close()
 }
 
-func (c *RTMIDIContext) HasDeviceOpen() bool {
+func (c *RTMIDIContext) IsOpen() bool {
 	return c.currentIn != nil && c.currentIn.IsOpen()
 }
-
-func (c *RTMIDIContext) TryToOpenBy(namePrefix string, takeFirst bool) {
-	if namePrefix == "" && !takeFirst {
-		return
-	}
-	for input := range c.InputDevices {
-		if takeFirst || strings.HasPrefix(input.String(), namePrefix) {
-			input.Open()
-			return
-		}
-	}
-	if takeFirst {
-		fmt.Errorf("Could not find any MIDI Input.\n")
-	} else {
-		fmt.Errorf("Could not find any default MIDI Input starting with \"%s\".\n", namePrefix)
-	}
-}

tracker/model.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+	"strings"
 
 	"github.com/vsariola/sointu"
 )
@@ -126,19 +127,14 @@ type (
 	Dialog int
 
 	MIDIContext interface {
-		InputDevices(yield func(MIDIDevice) bool)
+		InputDevices(yield func(string) bool)
+		Open(name string) error
 		Close()
-		HasDeviceOpen() bool
-		TryToOpenBy(name string, first bool)
+		IsOpen() bool
 	}
 
 	NullMIDIContext struct{}
 
-	MIDIDevice interface {
-		String() string
-		Open() error
-	}
-
 	InstrumentTab int
 )
 
@@ -221,6 +217,15 @@ func NewModel(broker *Broker, synthers []sointu.Synther, midiContext MIDIContext
 	return m
 }
 
+func FindMIDIDeviceByPrefix(c MIDIContext, prefix string) (input string, ok bool) {
+	for input := range c.InputDevices {
+		if strings.HasPrefix(input, prefix) {
+			return input, true
+		}
+	}
+	return "", false
+}
+
 func (m *Model) change(kind string, t ChangeType, severity ChangeSeverity) func() {
 	if m.changeLevel == 0 {
 		m.changeType = NoChange
@@ -434,10 +439,10 @@ func (d *modelData) Copy() modelData {
 	return ret
 }
 
-func (m NullMIDIContext) InputDevices(yield func(MIDIDevice) bool) {}
-func (m NullMIDIContext) Close()                                   {}
-func (m NullMIDIContext) HasDeviceOpen() bool                      { return false }
-func (m NullMIDIContext) TryToOpenBy(name string, first bool)      {}
+func (m NullMIDIContext) InputDevices(yield func(string) bool) {}
+func (m NullMIDIContext) Open(name string) error               { return nil }
+func (m NullMIDIContext) Close()                               {}
+func (m NullMIDIContext) IsOpen() bool                         { return false }
 
 func (m *Model) resetSong() {
 	m.d.Song = defaultSong.Copy()