Help Expected end of line, etc. but found end of script.

here is the sctipt ive tried to write, its not finished so some of the things my seem a bit weird at the moment but here it is as it stands

global okflag

set okflag to false

set front_app to (path tofrontmost applicationasUnicode text)

-- check if iTunes is running

tell application "System Events"

if process "iTunes" exists then

set okflag to true--iTunes is running

end if

end tell

if okflag is true then

set Timer to ""

display dialog "Sleep Time (Minutes)" default answerTimerbuttons {"Cancel", "OK"} default button 2

set Timer to text returned of the result

delay Timer * 60

tell application "iTunes"

set currentVolume to the sound volume

if (player state is playing) then

repeat

--Fade down

repeat with i from currentVolume to 0 by -1

set the sound volume to i

delay 1

end repeat

pause

--Restore original volume

set the sound volume to currentVolume

exit repeat

end repeat

if okflag is false then

display dialog "iTunes not playing" buttons {"OK"} default button 1 with icon stop

end if

end

it doesnt seem to work after the tell "iTunes part i copied and pasted from another applescript

(the purple text)