Rename 2x images to "@2x" and move them to a parallel folder structure of 1x images

rename_retina.applescript

set doubleDirPath_ to "path to 2x images"
set singleDirPath_ to "path to 1x images" -- also destination path
set ext_ to ".png"
set extLen_ to length of ext_
set suffix_ to "@2x"

tell application "Finder"
	set doubleDir_ to folder doubleDirPath_
	set singleDir_ to folder singleDirPath_
	set dirs_ to (get every item of doubleDir_)
	repeat with dir_ in dirs_
		
		set dirName_ to (get name of dir_ as string)
		set destDir_ to (get folder (singleDirPath_ & ":" & dirName_ as string))
		
		set imgs_ to (get every item of dir_ whose name of it ends with ext_)
		repeat with img_ in imgs_
			set oldName_ to name of img_
			set oldLen_ to length of oldName_
			set oldName_ to (characters 1 thru (oldLen_ - extLen_) of oldName_ as string)
			
			set newName_ to ""
			if oldName_ does not end with suffix_ then
				set newName_ to (oldName_ & suffix_ & ext_)
				set name of img_ to newName_
			end if
			
			delete file (get name of img_ as string) of destDir_
			duplicate img_ to destDir_
		end repeat
	end repeat
end tell