class Sprockets::BabelProcessor

def self.cache_key
  instance.cache_key
end

def self.call(input)
  instance.call(input)
end

def self.instance
  @instance ||= new
end

def call(input)
  data = input[:data]
  result = input[:cache].fetch(@cache_key + [input[:filename]] + [data]) do
    opts = {
      'moduleRoot' => nil,
      'filename' => input[:filename],
      'filenameRelative' => PathUtils.split_subpath(input[:load_path], input[:filename]),
      'sourceFileName' => File.basename(input[:filename]),
      'sourceMapTarget' => input[:filename]
    }.merge(@options)
    if opts['moduleIds'] && opts['moduleRoot']
      opts['moduleId'] ||= File.join(opts['moduleRoot'], input[:name])
    elsif opts['moduleIds']
      opts['moduleId'] ||= input[:name]
    end
    Autoload::Babel::Transpiler.transform(data, opts)
  end
  map = SourceMapUtils.format_source_map(result["map"], input)
  map = SourceMapUtils.combine_source_maps(input[:metadata][:map], map)
  { data: result['code'], map: map }
end

def initialize(options = {})
  @options = options.merge({
    'blacklist' => (options['blacklist'] || []) + ['useStrict'],
    'sourceMap' => true
  }).freeze
  @cache_key = [
    self.class.name,
    Autoload::Babel::Transpiler::VERSION,
    Autoload::Babel::Source::VERSION,
    VERSION,
    @options
  ].freeze
end