fix Bluetooth client volume lookup

Author: kasnder

backend/pulseaudio/pulseaudio.go

@@ -393,13 +393,27 @@ func (pa *PulseAudioBackend) findSinkInput(name string) (pulseaudio.SinkInput, e
 		return pulseaudio.SinkInput{}, fmt.Errorf("failed to list sink inputs: %w", err)
 	}
 	for _, s := range inputs {
-		if strings.EqualFold(clientName(s.PropList), name) {
+		if sinkInputMatchesName(s.PropList, name) {
 			return s, nil
 		}
 	}
 	return pulseaudio.SinkInput{}, &NotFoundError{Resource: "client", Name: name}
 }
 
+// sinkInputMatchesName accepts both the raw PulseAudio stream name and the
+// Bluetooth display name exposed by parsePulseBluetoothSink. Bluetooth A2DP
+// inputs are implemented as module-loopback streams whose raw media.name is
+// "Loopback from <device>", while the API deliberately exposes just <device>.
+func sinkInputMatchesName(props map[string]string, name string) bool {
+	if strings.EqualFold(clientName(props), name) {
+		return true
+	}
+	if props["media.icon_name"] == "audio-card-bluetooth" {
+		return strings.EqualFold(strings.TrimPrefix(props["media.name"], "Loopback from "), name)
+	}
+	return false
+}
+
 func (pa *PulseAudioBackend) parseSinkInput(s pulseaudio.SinkInput) AudioClient {
 	switch pa.kind {
 	case ServerPipeWire:

backend/pulseaudio/pulseaudio_test.go

@@ -127,6 +127,49 @@ func TestCloneProps(t *testing.T) {
 	}
 }
 
+func TestSinkInputMatchesName(t *testing.T) {
+	tests := []struct {
+		name   string
+		props  map[string]string
+		target string
+		want   bool
+	}{
+		{
+			name: "regular stream name",
+			props: map[string]string{
+				"media.name": "Playback",
+			},
+			target: "Playback",
+			want:   true,
+		},
+		{
+			name: "bluetooth display name",
+			props: map[string]string{
+				"media.name":      "Loopback from Cloud Remaster",
+				"media.icon_name": "audio-card-bluetooth",
+			},
+			target: "Cloud Remaster",
+			want:   true,
+		},
+		{
+			name: "non-bluetooth prefix is not stripped",
+			props: map[string]string{
+				"media.name": "Loopback from Cloud Remaster",
+			},
+			target: "Cloud Remaster",
+			want:   false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := sinkInputMatchesName(tt.props, tt.target); got != tt.want {
+				t.Fatalf("sinkInputMatchesName() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
 func TestExtractModuleSource(t *testing.T) {
 	tests := []struct {
 		name     string