# frozen_string_literal: true

module API
  # This API is responsible for collecting error tracking information
  # from sentry client. It allows us to use GitLab as an alternative to
  # sentry backend. For more details see https://gitlab.com/gitlab-org/gitlab/-/issues/329596.
  class ErrorTracking::Collector < ::API::Base
    feature_category :error_tracking

    content_type :envelope, 'application/x-sentry-envelope'
    content_type :json, 'application/json'
    content_type :txt, 'text/plain'
    default_format :envelope

    before do
      not_found!('Project') unless project
      not_found! unless feature_enabled?
      not_found! unless active_client_key?
    end

    helpers do
      def project
        @project ||= find_project(params[:id])
      end

      def feature_enabled?
        project.error_tracking_setting&.enabled? &&
          project.error_tracking_setting&.integrated_client?
      end

      def find_client_key(public_key)
        return unless public_key.present?

        project.error_tracking_client_keys.active.find_by_public_key(public_key)
      end

      def active_client_key?
        public_key = extract_public_key

        find_client_key(public_key)
      end

      def extract_public_key
        # Some SDK send public_key as a param. In this case we don't need to parse headers.
        return params[:sentry_key] if params[:sentry_key].present?

        begin
          ::ErrorTracking::Collector::SentryAuthParser.parse(request)[:public_key]
        rescue StandardError
          bad_request!('Failed to parse sentry request')
        end
      end
    end

    desc 'Submit error tracking event to the project as envelope' do
      detail 'This feature was introduced in GitLab 14.1.'
    end
    params do
      requires :id, type: String, desc: 'The ID of a project'
    end
    post 'error_tracking/collector/api/:id/envelope' do
      # There is a reason why we have such uncommon path.
      # We depend on a client side error tracking software which
      # modifies URL for its own reasons.
      #
      # When we give user a URL like this
      #   HOST/api/v4/error_tracking/collector/123
      #
      # Then error tracking software will convert it like this:
      #   HOST/api/v4/error_tracking/collector/api/123/envelope/

      begin
        parsed_request = ::ErrorTracking::Collector::SentryRequestParser.parse(request)
      rescue StandardError
        bad_request!('Failed to parse sentry request')
      end

      type = parsed_request[:request_type]

      # Sentry sends 2 requests on each exception: transaction and event.
      # Everything else is not a desired behavior.
      unless type == 'transaction' || type == 'event'
        render_api_error!('400 Bad Request', 400)

        break
      end

      # We don't have use for transaction request yet,
      # so we record only event one.
      if type == 'event'
        ::ErrorTracking::CollectErrorService
          .new(project, nil, event: parsed_request[:event])
          .execute
      end

      # Collector should never return any information back.
      # Because DSN and public key are designed for public use,
      # it is safe only for submission of new events.
      no_content!
    end

    desc 'Submit error tracking event to the project' do
      detail 'This feature was introduced in GitLab 14.1.'
    end
    params do
      requires :id, type: String, desc: 'The ID of a project'
    end
    post 'error_tracking/collector/api/:id/store' do
      # There is a reason why we have such uncommon path.
      # We depend on a client side error tracking software which
      # modifies URL for its own reasons.
      #
      # When we give user a URL like this
      #   HOST/api/v4/error_tracking/collector/123
      #
      # Then error tracking software will convert it like this:
      #   HOST/api/v4/error_tracking/collector/api/123/store/

      begin
        parsed_body = Gitlab::Json.parse(request.body.read)
      rescue StandardError
        bad_request!('Failed to parse sentry request')
      end

      ::ErrorTracking::CollectErrorService
        .new(project, nil, event: parsed_body)
        .execute

      # Collector should never return any information back.
      # Because DSN and public key are designed for public use,
      # it is safe only for submission of new events.
      no_content!
    end
  end
end