module Sprockets::Bower

def read_bower_main(dirname, filename)
  bower = JSON.parse(File.read(filename), create_additions: false)
  case bower['main']
  when String
    yield File.expand_path(bower['main'], dirname)
  when Array
    bower['main'].each do |name|
      yield File.expand_path(name, dirname)
    end
  end
end

def resolve_alternates(load_path, logical_path, &block)
  super
  # bower.json can only be nested one level deep
  if !logical_path.index('/')
    dirname = File.join(load_path, logical_path)
    stat    = self.stat(dirname)
    if stat && stat.directory?
      filenames = POSSIBLE_BOWER_JSONS.map { |basename| File.join(dirname, basename) }
      filename  = filenames.detect { |fn| self.file?(fn) }
      if filename
        read_bower_main(dirname, filename, &block)
      end
    end
  end
  nil
end