convert_images.rb

require 'down'

src = File.open("about-me.html", "r") { |file| file.read }

count = 0
src.gsub!(/(src|data-flickity-lazyload)="(\S+)"/) { |match|
  extension = if ($2.include? 'jpg' or $2.include? 'jpeg')
                "jpg"
              elsif ($2.include? 'png')
                "png"
              elsif ($2.include? 'gif')
                "gif"
              end
  if extension.nil?
    match
  else
    file = "img/#{count}.#{extension}"
    Down.download($2, destination:"./#{file}")
    count += 1
    "#{$1}=\"#{file}\""
  end
}

File.open("about-me.html", "w+") { |file| file.puts src }