module Sprockets::CoffeeScriptProcessor

def self.cache_key
  @cache_key ||= "#{name}:#{Autoload::CoffeeScript::Source.version}:#{VERSION}".freeze
end

def self.call(input)
  data = input[:data]
  js, map = input[:cache].fetch([self.cache_key, data]) do
    result = Autoload::CoffeeScript.compile(
      data,
      sourceMap: "v3",
      sourceFiles: [File.basename(input[:filename])],
      generatedFile: input[:filename]
    )
    [result['js'], JSON.parse(result['v3SourceMap'])]
  end
  map = SourceMapUtils.format_source_map(map, input)
  map = SourceMapUtils.combine_source_maps(input[:metadata][:map], map)
  { data: js, map: map }
end