chore: add Apache License 2.0 and ignore build directory

src/config/config.go

@@ -37,6 +37,66 @@ func Parse() Settings {
 	return settings
 }
 
+type OutputMode string
+
+const (
+	OutputTerminal OutputMode = "terminal"
+	OutputOverlay  OutputMode = "overlay"
+	OutputBoth     OutputMode = "both"
+)
+
+type OverlayBackend string
+
+const (
+	BackendAuto    OverlayBackend = "auto"
+	BackendWayland OverlayBackend = "wayland"
+	BackendX11     OverlayBackend = "x11"
+)
+
+type OverlaySettings struct {
+	Backend      OverlayBackend
+	Opacity      float64
+	FontSize     int
+	BottomMargin int
+	MaxWidth     int
+	Monitor      string
+	FinalTimeout time.Duration
+	ClickThrough bool
+}
+
+type DesktopSettings struct {
+	Settings
+	Output  OutputMode
+	Overlay OverlaySettings
+}
+
+func ParseDesktop() DesktopSettings {
+	flags := flag.CommandLine
+	var desktop DesktopSettings
+	var mode string
+	var output string
+	var backend string
+	flags.StringVar(&mode, "mode", "", "caption mode: vad or fixed (required)")
+	flags.DurationVar(&desktop.ChunkDuration, "chunk-duration", time.Second, "fixed chunk size or VAD preview refresh interval")
+	flags.StringVar(&desktop.ModelsDir, "models-dir", DefaultModelsDir, "directory containing downloaded Sherpa models")
+	flags.IntVar(&desktop.Threads, "threads", 2, "CPU threads used by recognition and VAD")
+	flags.Float64Var(&desktop.PreviewThresholdDB, "preview-threshold-dbfs", -45, "RMS dBFS threshold used to begin VAD previews")
+	flags.StringVar(&output, "output", "", "caption output: terminal, overlay, or both (required)")
+	flags.StringVar(&backend, "overlay-backend", "auto", "display backend: auto, wayland, or x11")
+	flags.Float64Var(&desktop.Overlay.Opacity, "overlay-opacity", 0.90, "caption background opacity from 0 to 1")
+	flags.IntVar(&desktop.Overlay.FontSize, "overlay-font-size", 28, "caption font size in logical pixels")
+	flags.IntVar(&desktop.Overlay.BottomMargin, "overlay-bottom-margin", 100, "distance from the monitor bottom in logical pixels")
+	flags.IntVar(&desktop.Overlay.MaxWidth, "overlay-max-width", 1200, "maximum caption width in logical pixels")
+	flags.StringVar(&desktop.Overlay.Monitor, "overlay-monitor", "auto", "monitor selection: auto, numeric index, or connector name")
+	flags.DurationVar(&desktop.Overlay.FinalTimeout, "overlay-final-timeout", 4*time.Second, "how long a final caption remains; zero waits for replacement")
+	flags.BoolVar(&desktop.Overlay.ClickThrough, "overlay-click-through", true, "pass pointer input through the caption window")
+	flag.Parse()
+	desktop.Mode = Mode(mode)
+	desktop.Output = OutputMode(output)
+	desktop.Overlay.Backend = OverlayBackend(backend)
+	return desktop
+}
+
 func (s Settings) Validate() error {
 	if s.Mode != ModeFixed && s.Mode != ModeVAD {
 		return errors.New("--mode is required and must be either fixed or vad")
@@ -49,3 +109,34 @@ func (s Settings) Validate() error {
 	}
 	return nil
 }
+
+func (s DesktopSettings) Validate() error {
+	if err := s.Settings.Validate(); err != nil {
+		return err
+	}
+	if s.Output != OutputTerminal && s.Output != OutputOverlay && s.Output != OutputBoth {
+		return errors.New("--output is required and must be terminal, overlay, or both")
+	}
+	if s.Overlay.Backend != BackendAuto && s.Overlay.Backend != BackendWayland && s.Overlay.Backend != BackendX11 {
+		return errors.New("--overlay-backend must be auto, wayland, or x11")
+	}
+	if s.Overlay.Opacity < 0 || s.Overlay.Opacity > 1 {
+		return errors.New("--overlay-opacity must be between 0 and 1")
+	}
+	if s.Overlay.FontSize <= 0 {
+		return errors.New("--overlay-font-size must be positive")
+	}
+	if s.Overlay.BottomMargin < 0 {
+		return errors.New("--overlay-bottom-margin cannot be negative")
+	}
+	if s.Overlay.MaxWidth <= 0 {
+		return errors.New("--overlay-max-width must be positive")
+	}
+	if s.Overlay.FinalTimeout < 0 {
+		return errors.New("--overlay-final-timeout cannot be negative")
+	}
+	if s.Overlay.Monitor == "" {
+		return errors.New("--overlay-monitor cannot be empty")
+	}
+	return nil
+}

src/config/config_test.go

@@ -14,3 +14,44 @@ func TestSettingsValidate(t *testing.T) {
 		t.Fatal("missing mode unexpectedly passed")
 	}
 }
+
+func validDesktopSettings() DesktopSettings {
+	return DesktopSettings{
+		Settings: Settings{Mode: ModeVAD, ChunkDuration: time.Second, Threads: 2},
+		Output:   OutputOverlay,
+		Overlay: OverlaySettings{
+			Backend: BackendAuto, Opacity: 0.9, FontSize: 28, BottomMargin: 100,
+			MaxWidth: 1200, Monitor: "auto", FinalTimeout: 4 * time.Second, ClickThrough: true,
+		},
+	}
+}
+
+func TestDesktopSettingsValidate(t *testing.T) {
+	if err := validDesktopSettings().Validate(); err != nil {
+		t.Fatalf("valid desktop settings failed: %v", err)
+	}
+
+	tests := []struct {
+		name   string
+		change func(*DesktopSettings)
+	}{
+		{"missing output", func(s *DesktopSettings) { s.Output = "" }},
+		{"invalid backend", func(s *DesktopSettings) { s.Overlay.Backend = "other" }},
+		{"negative opacity", func(s *DesktopSettings) { s.Overlay.Opacity = -0.1 }},
+		{"large opacity", func(s *DesktopSettings) { s.Overlay.Opacity = 1.1 }},
+		{"zero font", func(s *DesktopSettings) { s.Overlay.FontSize = 0 }},
+		{"negative margin", func(s *DesktopSettings) { s.Overlay.BottomMargin = -1 }},
+		{"zero width", func(s *DesktopSettings) { s.Overlay.MaxWidth = 0 }},
+		{"empty monitor", func(s *DesktopSettings) { s.Overlay.Monitor = "" }},
+		{"negative timeout", func(s *DesktopSettings) { s.Overlay.FinalTimeout = -time.Second }},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			settings := validDesktopSettings()
+			test.change(&settings)
+			if err := settings.Validate(); err == nil {
+				t.Fatal("invalid settings unexpectedly passed")
+			}
+		})
+	}
+}