Add detection of connected headphone for volume level

components/volume_level.go

@@ -7,6 +7,17 @@ import (
 	"strings"
 )
 
+const (
+	// find an entry that has `headphone jack` in it using `amixer controls`
+	headphone_numid = "1"
+	sound_card      = "0"
+
+	speaker_up_icon     = ""
+	speaker_mute_icon   = " MUTE"
+	headphone_up_icon   = ""
+	headphone_mute_icon = " MUTE"
+)
+
 func main() {
 	response, _ := exec.Command("amixer", "sget", "Master").Output()
 
@@ -16,9 +27,22 @@ func main() {
 	level := levelPattern.FindString(string(response))
 	status := strings.Trim(statusPattern.FindString(string(response)), "[]")
 
+	headPhoneStatusArgs := strings.Split(fmt.Sprintf("-c %s cget numid=%s", sound_card, headphone_numid), " ")
+	headphoneResponse, _ := exec.Command("amixer", headPhoneStatusArgs...).Output()
+	headPhoneStatusPattern, _ := regexp.Compile("values=(on|off)")
+	headPhoneStatus := strings.Trim(headPhoneStatusPattern.FindString(string(headphoneResponse)), "values=")
+
+	upIcon := speaker_up_icon
+	muteIcon := speaker_mute_icon
+
+	if headPhoneStatus == "on" {
+		upIcon = headphone_up_icon
+		muteIcon = headphone_mute_icon
+	}
+
 	if status == "off" {
-		fmt.Println(" MUTE")
+		fmt.Println(muteIcon)
 	} else {
-		fmt.Println(fmt.Sprintf(" %s", level))
+		fmt.Println(fmt.Sprintf("%s %s", upIcon, level))
 	}
 }