Ruby script for batch image resize and optimisation

imagebatch.rb

#!/usr/bin/env ruby
# frozen_string_literal: true

# brew install imagemagick advancecomp gifsicle jhead jpegoptim jpeg optipng pngcrush pngquant jonof/kenutils/pngout
# gem install mini_magick image_optim image_optim_pack

# Usage: ./imagebatch.rb [src_dir] [dest_dir] [resize="200x200"] [format="jpg"]

require "mini_magick"
require "image_optim"

def single(file_path, dest_path = nil, resize = nil, format = nil)
  image_optim = ImageOptim.new({
    :svgo => false,
    :oxipng => false
  })

  filename = file_path.match(/[^\/\\]+$/)[0]
  image = MiniMagick::Image.open(file_path)
  image.resize resize if resize
  if dest_path.nil?
    dest_path = file_path
  else
    dest_path = File.join(dest_path, filename)
  end

  if format
    image.format format
    dest_path = dest_path.gsub(/\.png|\.jpe?g|\.webp|\.gif$/i, ".#{format}")
    image.write dest_path
    File.delete(file_path)
  end
  
  puts dest_path

  image_optim.optimize_image!(dest_path)
end

def all(src_path, dest_path = nil, resize = nil, format = nil)
  dest_path = src_path if dest_path.nil?

  Dir.foreach(src_path) do |file|
    next if !/\.png|\.jpe?g|\.webp|\.gif$/i.match(file)
    file_path = File.join(src_path, file)
    single(file_path, dest_path, resize, format)
  end
end

def single_command(file_path, *args)
  single(file_path, *args)
end

def all_command(src_path, *args)
  all(src_path, *args)
end


fn_index = {
  "single" => method(:single_command),
  "all" => method(:all_command)
}

fn_index[ARGV[0]].call(ARGV[1], ARGV[2], ARGV[3], ARGV[4])