increase/decrease volume using current spotify volume

README.md

@@ -50,6 +50,10 @@ seconds to jump ahead.
 seconds to jump backwards.
 * To change volume, type `spotify volume N` where N is a number between
 0 and 100.
+* Increase volume, type `spotify increasevolume N` where N is a number between
+0 and 100 that you want to increment by.
+* Decrease volume, type `spotify decreasevolume N` where N is a number between
+0 and 100 that you want to decrement by.
 * To toggle shuffle, type `spotify shuffle`.
 * To toggle repeat, type `spotify repeat`.
 * To show a list of these commands, just type `spotify`.

SpotifyControl

@@ -14,6 +14,8 @@ on run argv
     set msg to msg & "  shuffle            - Toggle shuffle\n"
     set msg to msg & "  repeat             - Toggle repeat\n"
     set msg to msg & "  volume N           - Set Volume to N (0...100)\n"
+    set msg to msg & "  increasevolume N   - Increment Volume by N (0...100)\n"
+    set msg to msg & "  decreasevolume N   - Decrement Volume by N (0...100)\n"
     return msg
   end if
   set command to item 1 of argv
@@ -101,6 +103,28 @@ on run argv
       end tell
       return "Changed volume to " & newVolume
 
+    else if command is equal to "increasevolume" then
+      set volumeInc to item 2 of argv as real
+      tell application "Spotify"
+        set currentVolume to sound volume
+        set newVolume to currentVolume + volumeInc
+        if newVolume < 0 then set newVolume to 0
+        if newVolume > 100 then set newVolume to 100
+        set sound volume to newVolume
+      end tell
+      return "Changed volume to " & newVolume
+
+    else if command is equal to "decreasevolume" then
+      set volumeInc to item 2 of argv as real
+      tell application "Spotify"
+        set currentVolume to sound volume
+        set newVolume to currentVolume - volumeInc
+        if newVolume < 0 then set newVolume to 0
+        if newVolume > 100 then set newVolume to 100
+        set sound volume to newVolume
+      end tell
+      return "Changed volume to " & newVolume
+
     else if command is equal to "shuffle" then
       tell application "Spotify"
         set shuffling to not shuffling