only send when track changes

bin/mpd-monitor

@@ -1,10 +1,23 @@
 #!/bin/sh
+ID=$(mpc current -f %id% )
 mpc idleloop |
-  while read event; do 
-    if [[ $event == "player" ]]; then
-      dunstctl close-all
-      TITLE=$(mpc status -f %title% | awk 'NR==1')
-      ARTIST=$(mpc status -f %artist% | awk 'NR==1')
+  while read -r event; do 
+    # if a player event is not output, skip rest of loop
+    [ "$event" = "player" ] || continue
+
+    # get current id to compare to init id
+    NEW_ID=$(mpc current -f %id%)
+    # if a player even is output, but the track has not changed, skip rest of loop
+    [ "$NEW_ID" != "$ID" ] || continue
+    ID=$NEW_ID
+
+    dunstctl close-all
+    TITLE=$(mpc current -f %title%)
+    ARTIST=$(mpc current -f %artist%)
+
+    if [ -z $TITLE ]; then
+      notify-send "End of queue or queue empty" -i :
+    else
       notify-send "$TITLE" "$ARTIST" -i :
     fi
   done