require 'rest-core/middleware'

# http://tools.ietf.org/html/rfc6749
class RestCore::Oauth2Header
  def self.members; [:access_token_type, :access_token]; end
  include RestCore::Middleware

  def call env, &k
    start_time = Time.now
    headers    = build_headers(env)
    auth       = headers['Authorization']
    event      = Event::WithHeader.new(Time.now - start_time,
                   "Authorization: #{auth}") if auth

    app.call(log(env.merge(REQUEST_HEADERS => headers), event), &k)
  end

  def build_headers env
    auth = case token = access_token(env)
           when String
             token
           when Hash
            token.map{ |(k, v)| "#{k}=\"#{v}\"" }.join(', ')
           end

    if auth
      {'Authorization' => "#{access_token_type(env)} #{auth}"}
    else
      {}
    end.merge(env[REQUEST_HEADERS])
  end
end