module Doorkeeper::Helpers::Controller

def authenticate_admin!
  instance_eval(&Doorkeeper.configuration.authenticate_admin)
end

def authenticate_resource_owner!
  current_resource_owner
end

def config_methods
  @methods ||= Doorkeeper.configuration.access_token_methods
end

def current_resource_owner
  instance_eval(&Doorkeeper.configuration.authenticate_resource_owner)
end

def doorkeeper_token
  @token ||= OAuth::Token.authenticate request, *config_methods
end

def get_error_response_from_exception(exception)
  error_name = case exception
               when Errors::InvalidTokenStrategy
                 :unsupported_grant_type
               when Errors::InvalidAuthorizationStrategy
                 :unsupported_response_type
               when Errors::MissingRequestStrategy
                 :invalid_request
               end
  OAuth::ErrorResponse.new name: error_name, state: params[:state]
end

def handle_token_exception(exception)
  error = get_error_response_from_exception exception
  self.headers.merge! error.headers
  self.response_body = error.body.to_json
  self.status        = error.status
end

def resource_owner_from_credentials
  instance_eval(&Doorkeeper.configuration.resource_owner_from_credentials)
end

def server
  @server ||= Server.new(self)
end

def skip_authorization?
  !!instance_exec([@server.current_resource_owner, @pre_auth.client], &Doorkeeper.configuration.skip_authorization)
end