# frozen_string_literal: true

# Use for authentication only, in particular for Rack::Attack.
# Does not perform authorization of scopes, etc.
module Gitlab
  module Auth
    class RequestAuthenticator
      include AuthFinders

      attr_reader :request

      def initialize(request)
        @request = request
      end

      def user(request_formats)
        request_formats.each do |format|
          user = find_sessionless_user(format)

          return user if user
        end

        find_user_from_warden
      end

      def runner
        find_runner_from_token
      rescue Gitlab::Auth::AuthenticationError
        nil
      end

      def find_sessionless_user(request_format)
        find_user_from_dependency_proxy_token ||
          find_user_from_web_access_token(request_format, scopes: [:api, :read_api]) ||
          find_user_from_feed_token(request_format) ||
          find_user_from_static_object_token(request_format) ||
          find_user_from_basic_auth_job ||
          find_user_from_job_token ||
          find_user_from_personal_access_token_for_api_or_git ||
          find_user_for_git_or_lfs_request
      rescue Gitlab::Auth::AuthenticationError
        nil
      end

      # To prevent Rack Attack from incorrectly rate limiting
      # authenticated Git activity, we need to authenticate the user
      # from other means (e.g. HTTP Basic Authentication) only if the
      # request originated from a Git or Git LFS
      # request. Repositories::GitHttpClientController or
      # Repositories::LfsApiController normally does the authentication,
      # but Rack Attack runs before those controllers.
      def find_user_for_git_or_lfs_request
        return unless git_or_lfs_request?

        find_user_from_lfs_token || find_user_from_basic_auth_password
      end

      def find_user_from_personal_access_token_for_api_or_git
        return unless api_request? || git_or_lfs_request?

        find_user_from_personal_access_token
      end

      def valid_access_token?(scopes: [])
        validate_access_token!(scopes: scopes)

        true
      rescue Gitlab::Auth::AuthenticationError
        false
      end

      private

      def access_token
        strong_memoize(:access_token) do
          super || find_personal_access_token_from_http_basic_auth
        end
      end

      def route_authentication_setting
        @route_authentication_setting ||= {
          job_token_allowed: api_request?,
          basic_auth_personal_access_token: api_request? || git_request?
        }
      end

      def find_user_from_dependency_proxy_token
        return unless dependency_proxy_request?

        token, _ = ActionController::HttpAuthentication::Token.token_and_options(current_request)

        return unless token

        user_or_deploy_token = ::DependencyProxy::AuthTokenService.user_or_deploy_token_from_jwt(token)

        # Do not return deploy tokens
        # See https://gitlab.com/gitlab-org/gitlab/-/issues/342481
        return unless user_or_deploy_token.is_a?(::User)

        user_or_deploy_token
      rescue ActiveRecord::RecordNotFound
        nil # invalid id used return no user
      end

      def dependency_proxy_request?
        Gitlab::PathRegex.dependency_proxy_route_regex.match?(current_request.path)
      end
    end
  end
end
