class Sprockets::SasscProcessor

def call(input)
  context = input[:environment].context_class.new(input)
  options = engine_options(input, context)
  engine = Autoload::SassC::Engine.new(input[:data], options)
  data = Utils.module_include(Autoload::SassC::Script::Functions, @functions) do
    engine.render
  end
  match_data = data.match(/(.*)\n\/\*# sourceMappingURL=data:application\/json;base64,(.+) \*\//m)
  css, map = match_data[1], Base64.decode64(match_data[2])
  map = SourceMapUtils.combine_source_maps(
    input[:metadata][:map],
    change_source(SourceMapUtils.decode_json_source_map(map)["mappings"], input[:source_path])
  )
  context.metadata.merge(data: css, map: map)
end

def change_source(mappings, source)
  mappings.each { |m| m[:source] = source }
end

def engine_options(input, context)
  merge_options({
    filename: input[:filename],
    syntax: self.class.syntax,
    load_paths: input[:environment].paths,
    importer: @importer_class,
    source_map_embed: true,
    source_map_file: '.',
    sprockets: {
      context: context,
      environment: input[:environment],
      dependencies: context.metadata[:dependencies]
    }
  })
end

def initialize(options = {}, &block)
  @cache_version = options[:cache_version]
  @cache_key = "#{self.class.name}:#{VERSION}:#{Autoload::SassC::VERSION}:#{@cache_version}".freeze
  @importer_class = options[:importer]
  @sass_config = options[:sass_config] || {}
  @functions = Module.new do
    include SassProcessor::Functions
    include options[:functions] if options[:functions]
    class_eval(&block) if block_given?
  end
end