Convert normal image name to retina image name

image_renamer.rb

#!env ruby
require 'rubygems'
require 'fileutils'

images_dir = ARGV[0]

if images_dir == nil
  puts "Error! Input images directory"
  exit
end

if !FileTest.exist?(images_dir)
  puts "Error! There is no such directory #{images_dir}"
  exit
end

def image_renamer(arg_dir)
  images = [];

  Dir.entries(arg_dir).each do |filename|
    # Do recursively
    if FileTest.directory?(arg_dir + "/" + filename)
      next if /\.+/ =~ filename
      image_renamer(arg_dir + "/" + filename)
    end


    img_type = File.extname(filename).downcase
    if (img_type == '.png' || img_type == '.jpg' || img_type == '.tif')
      ext = File.extname(filename)
      basename = File.basename(filename, ext)
      dir = File.dirname(filename)

      next if /(.+)@2x(#{ext})$/ =~ filename

      export_dir = "./2x_#{arg_dir}"
      if !FileTest.exist?("export_dir")
        FileUtils.mkdir_p(export_dir)
      end

      FileUtils.cp("#{arg_dir}/#{basename}#{img_type}", "#{export_dir}/#{basename}@2x#{img_type}")

    end
  end
end

image_renamer(ARGV[0])

puts "Renamed normal images to retina images"