class Middleman::Extensions::CacheBuster

def initialize(app, options_hash = ::Middleman::EMPTY_HASH, &block)
  super
  require 'set'
  @set_of_exts = Set.new(options.exts || app.config[:asset_extensions])
  @set_of_sources = Set.new options.sources
end

def manipulate_resource_list_container!(resource_list)
  resource_list.by_extensions(@set_of_sources).each do |r|
    next if Array(options.rewrite_ignore || []).any? do |i|
      ::Middleman::Util.path_match(i, "/#{r.destination_path}")
    end
    r.add_filter ::Middleman::InlineURLRewriter.new(:cache_buster,
                                                    app,
                                                    r,
                                                    url_extensions: @set_of_exts,
                                                    ignore: options.ignore,
                                                    proc: method(:rewrite_url))
  end
end

def rewrite_url(asset_path, _dirpath, _request_path)
  asset_path + '?' + Time.now.strftime('%s')
end