Ruby script for recursively renaming files and directories

rename.rb

#!/usr/bin/ruby

def rename(dir, map)
	Dir.foreach(dir) do |filename|
		next if filename =~ /^\.+$/ or File.directory?("#{dir}/#{filename}")
		(entry, extension) = filename.sub("file", "").split(".")
		entry.sub!(/^0+/, "")
		if map[entry].nil?
			raise "PROBLEM: no entry for file #{dir}/#{filename} with id #{entry}"
		else
			puts "Renaming #{dir}/#{filename} to #{dir}/#{map[entry] + (extension.nil? ? "" : "." + extension)}"
			File.rename("#{dir}/#{filename}", "#{dir}/#{map[entry] + (extension.nil? ? "" : "." + extension)}")
		end
	end
end

def recurse(dir, map)
	Dir.foreach(dir) do |dirname|
		next if dirname =~ /^\.+$/ or !File.directory?("#{dir}/#{dirname}")
		rename("#{dir}/#{dirname}", map) if dirname == "outputUrl"
		recurse("#{dir}/#{dirname}", map)
	end
end

map = {}
i = 1
STDIN.each_line do |listEntry|
	map[i.to_s] = listEntry.strip
	i += 1
end

recurse(".", map)