cmd/mxl-pattern/main.go

@@ -20,6 +20,7 @@ import (
 	"github.com/qvest-digital/go-mxl/mxl"
 	"github.com/spf13/pflag"
 
+	"mxl-pattern-generator/internal/audio"
 	"mxl-pattern-generator/internal/flowdef"
 	"mxl-pattern-generator/internal/generator"
 	"mxl-pattern-generator/internal/video"
@@ -418,6 +419,42 @@ func buildVideoConfig(args appArgs) (video.Config, error) {
 	}, nil
 }
 
+// buildAudioConfig returns nil when audio is disabled. An explicit audio flow
+// definition enables audio even when --channel is zero.
+func buildAudioConfig(args appArgs) (*audio.Config, error) {
+	if args.audioFlowDefFile == "" && args.audioChannels == 0 {
+		return nil, nil
+	}
+
+	var definition flowdef.Audio
+	if args.audioFlowDefFile != "" {
+		data, err := os.ReadFile(args.audioFlowDefFile)
+		if err != nil {
+			return nil, fmt.Errorf("read audio flow definition %q: %w", args.audioFlowDefFile, err)
+		}
+		definition, err = flowdef.ParseFloat32Audio(data)
+		if err != nil {
+			return nil, fmt.Errorf("parse audio flow definition %q: %w", args.audioFlowDefFile, err)
+		}
+	} else {
+		rate, ok := samplingRates[args.audioSamplingFreq]
+		if !ok {
+			return nil, fmt.Errorf("unsupported audio sample rate %q", args.audioSamplingFreq)
+		}
+		var err error
+		definition, err = flowdef.NewFloat32Audio(
+			args.audioUUID,
+			uint(args.audioChannels),
+			flowdef.Rational{Numerator: uint(rate.Num), Denominator: uint(rate.Den)},
+		)
+		if err != nil {
+			return nil, fmt.Errorf("build audio flow definition: %w", err)
+		}
+	}
+
+	return &audio.Config{Definition: definition}, nil
+}
+
 func main() {
 	parsed, err := parseArgs(os.Args[1:], os.Stdout, os.Stderr)
 	if err != nil {

cmd/mxl-pattern/main_test.go

@@ -162,3 +162,70 @@ func TestBuildVideoConfigFromFile(t *testing.T) {
 		t.Fatalf("rate = %d/%d, want file value 60000/1001", cfg.Rate().Num, cfg.Rate().Den)
 	}
 }
+
+func TestBuildAudioConfigDisabled(t *testing.T) {
+	cfg, err := buildAudioConfig(appArgs{})
+	if err != nil {
+		t.Fatalf("buildAudioConfig: %v", err)
+	}
+	if cfg != nil {
+		t.Fatalf("config = %+v, want nil for disabled audio", cfg)
+	}
+}
+
+func TestBuildAudioConfigFromArgs(t *testing.T) {
+	cfg, err := buildAudioConfig(appArgs{
+		audioUUID:         "b3bb5be7-9fe9-4324-a5bb-4c70e1084449",
+		audioChannels:     2,
+		audioSamplingFreq: "48",
+	})
+	if err != nil {
+		t.Fatalf("buildAudioConfig: %v", err)
+	}
+	if cfg == nil {
+		t.Fatal("config is nil")
+	}
+	if cfg.Channels() != 2 {
+		t.Fatalf("channels = %d, want 2", cfg.Channels())
+	}
+	if cfg.Rate().Num != 48000 || cfg.Rate().Den != 1 {
+		t.Fatalf("rate = %d/%d, want 48000/1", cfg.Rate().Num, cfg.Rate().Den)
+	}
+}
+
+func TestBuildAudioConfigFromFile(t *testing.T) {
+	definition, err := flowdef.NewFloat32Audio(
+		"b3bb5be7-9fe9-4324-a5bb-4c70e1084449",
+		8,
+		flowdef.Rational{Numerator: 96000, Denominator: 1},
+	)
+	if err != nil {
+		t.Fatalf("NewFloat32Audio: %v", err)
+	}
+	data, err := json.Marshal(definition)
+	if err != nil {
+		t.Fatalf("json.Marshal: %v", err)
+	}
+	path := t.TempDir() + "/audio.json"
+	if err := os.WriteFile(path, data, 0o600); err != nil {
+		t.Fatalf("os.WriteFile: %v", err)
+	}
+
+	cfg, err := buildAudioConfig(appArgs{
+		audioFlowDefFile:  path,
+		audioChannels:     2,
+		audioSamplingFreq: "48",
+	})
+	if err != nil {
+		t.Fatalf("buildAudioConfig: %v", err)
+	}
+	if cfg == nil {
+		t.Fatal("config is nil")
+	}
+	if cfg.Channels() != 8 {
+		t.Fatalf("channels = %d, want file value 8", cfg.Channels())
+	}
+	if cfg.Rate().Num != 96000 || cfg.Rate().Den != 1 {
+		t.Fatalf("rate = %d/%d, want file value 96000/1", cfg.Rate().Num, cfg.Rate().Den)
+	}
+}

internal/audio/config.go

@@ -0,0 +1,26 @@
+package audio
+
+import (
+	"mxl-pattern-generator/internal/flowdef"
+
+	"github.com/qvest-digital/go-mxl/mxl"
+)
+
+type Config struct {
+	Definition flowdef.Audio
+}
+
+func (c Config) ID() string {
+	return c.Definition.ID
+}
+
+func (c Config) Channels() uint {
+	return c.Definition.ChannelCount
+}
+
+func (c Config) Rate() mxl.Rational {
+	return mxl.Rational{
+		Num: int64(c.Definition.SampleRate.Numerator),
+		Den: int64(c.Definition.SampleRate.Denominator),
+	}
+}