This is a fish function -- store it inside ~/.config/fish/functions to use with fish. Renames all episodes in a directory to the TVDB naming-scheme and verbosely prints the changes. Ex: Series 1x01.mkv

rename-series.fish

#!/bin/fish
function rename-series --description 'rename-series <series_name> <season_number> <file_extension>'
	set count 0
	for file in *
		set count (math $count + 1)
		if test (math $count \< 10) = '1'
			mv -i -v "$file" "$argv[1] $argv[2]x0$count.$argv[3]"
		else
			mv -i -v "$file" "$argv[1] $argv[2]x$count.$argv[3]"
		end
	end
end