#!/usr/bin/env ruby

def extract(input:, size:, offsets:, output: "/tmp/out.png")
  `magick #{input} -crop #{size.map(&:to_s).join("x")}+#{offsets.map(&:to_s).join("+")} #{output}`
end

image_size = 200
image_plus_border_heigh = image_size + 44
image_plus_border_width = image_size + 46
init_offsets = [20, 180]
images_offsets = 3.times.flat_map do |x|
  3.times.map do |y|
    [
      init_offsets[0] + x * image_plus_border_width,
      init_offsets[1] + y * image_plus_border_heigh,
    ]
  end
end

images_offsets.each_with_index do |offsets, index|
  output = "crop-#{File.basename(ARGV[0], "png")}-#{index}.png"
  extract(
    input: ARGV[0],
    output: output,
    size: [image_size, image_size],
    offsets: offsets,
  )
  puts output
end