class Doorkeeper::TokensController

def client
  @client ||= Doorkeeper::OAuth::Client.authenticate(credentials)
end

def create
  response.headers.merge!({
    'Pragma'        => 'no-cache',
    'Cache-Control' => 'no-store',
  })
  if token.authorize
    render :json => token.authorization
  else
    render :json => token.error_response, :status => token.error_response.status
  end
end

def credentials
  methods = Doorkeeper.configuration.client_credentials_methods
  @credentials ||= Doorkeeper::OAuth::Client::Credentials.from_request(request, *methods)
end

def token
  unless defined?(@token) && @token
    case params[:grant_type]
    when 'password'
      owner = resource_owner_from_credentials
      @token = Doorkeeper::OAuth::PasswordAccessTokenRequest.new(client, owner, params)
    when 'client_credentials'
      @token = Doorkeeper::OAuth::ClientCredentialsRequest.new(Doorkeeper.configuration, client, params)
    else
      @token = Doorkeeper::OAuth::AccessTokenRequest.new(client, params)
    end
  end
  @token
end