tag tv show episodes from <SHOW NAME>_S<SEASON NUM>_E<EPISODE NUM>_<EPISODE ID>

gistfile1.scpt

set seasonNumPattern to "\\d\\d"
set episodeNumPattern to "\\d\\d"

tell application "iTunes"
	repeat with I from 1 to count tracks of user playlist "show"
		
		set track_ to track I of user playlist "show"
		set name_ to name of track_
		set seasonNum to (find text "(?<=S)(" & seasonNumPattern & ")" in name_ with regexp and string result) as integer
		set episodeNum to (find text "(?<=E)(" & episodeNumPattern & ")" in name_ with regexp and string result) as integer
		set showName to change "[[:space:]]+" into " " in (change "[[:punct:]]" into " " in (find text "^(.*)(?=S" & seasonNumPattern & ")" in name_ with regexp and string result) with regexp) with regexp
		set episodeId to change "^[[:space:]]" into "" in (change "[[:space:]]+" into " " in (change "[[:punct:]]" into " " in (find text "(?<=E" & episodeNumPattern & ")(.*)" in name_ with regexp and string result) with regexp) with regexp) with regexp
		
		set video kind of aTrack to TV show
		set show of aTrack to showName
		set season number of aTrack to seasonNum
		set episode number of aTrack to episodeNum
		set episode ID of aTrack to episodeId
		
	end repeat
end tell