(* 
  db iTunes Vol, Play, or Fade
  By David Battino, Batmosphere.com
  Based on ideas from Doug's AppleScripts and Mac OS Hints
  
  Code cleaned up and flattened by Jacob Rus
  
  This script fades out iTunes if it's playing and fades it in if it's stopped.
*)


-- So we can switch back to this after running the fade
global front_app
set front_app to app (path to frontmost application as Unicode text)

global itunes_state_
set itunes_state_ to my itunes_state()

prop parent : app "System Events"
tell parent to activate

if itunes_state_ is "playing" then
	tell app "iTunes" to set current_volume to sound volume
	set heyyou to "iTunes is cranked to " & current_volume & "." & ¬
		return & "Set the new volume (0-100):" --dialog message
	repeat
		display dialog heyyou default answer "0"
		set volume_ to text returned of result as number
		if volume_ is "0" then
			my fade by 0.01 from current_volume to 0
			exit repeat
		else
			try
				my fade by 0.01 from current_volume to volume_
				exit repeat
			on error
				beep
				set heyyou to "Please enter a number between 0 and 100."
			end try
		end if
	end repeat
else if itunes_state_ is "stopped" then
	tell app "iTunes" to set current_volume to sound volume
	repeat
		display dialog "iTunes is stopped." & return & ¬
			"The current volume is " & current_volume & "." & ¬
			return & "Begin playing at volume (1-100):" ¬
			default answer "70"
		set volume_ to text returned of result as number
		try
			my fade by 0.01 from 0 to volume_
			exit repeat
		on error
			beep
		end try
	end repeat
else if itunes_state_ is "" then
	beep
end if

tell front_app to activate


-- fade iTunes to the end_volume, delaying "delay" seconds for each step
to fade by delay_ from start_volume to end_volume
	tell app "iTunes"
		
		-- set the step size based on whether start or end volume is bigger
		set step_ to ((start_volume < end_volume) as integer * 2 - 1)
		
		repeat with i from start_volume to end_volume by step_
			set the sound volume to i
			delay delay_
		end repeat
	end tell
end fade

-- returns "playing", "stopped", or ""
on itunes_state()
	tell application "System Events"
		if process "iTunes" exists then
			tell app "iTunes"
				if player state is playing then
					return "playing"
				else
					return "stopped"
				end if
			end tell
		else
			return ""
		end if
	end tell
end itunes_state