# frozen_string_literal: true

module Projects
  class UpdateRemoteMirrorService < BaseService
    include Gitlab::Utils::StrongMemoize

    MAX_TRIES = 3

    def execute(remote_mirror, tries)
      return success unless remote_mirror.enabled?

      # Blocked URLs are a hard failure, no need to attempt to retry
      if Gitlab::UrlBlocker.blocked_url?(normalized_url(remote_mirror.url), schemes: Project::VALID_MIRROR_PROTOCOLS)
        hard_retry_or_fail(remote_mirror, _('The remote mirror URL is invalid.'), tries)
        return error(remote_mirror.last_error)
      end

      update_mirror(remote_mirror)

      success
    rescue Gitlab::Git::CommandError => e
      # This happens if one of the gitaly calls above fail, for example when
      # branches have diverged, or the pre-receive hook fails.
      hard_retry_or_fail(remote_mirror, e.message, tries)

      error(e.message)
    rescue StandardError => e
      remote_mirror.hard_fail!(e.message)
      raise e
    end

    private

    def normalized_url(url)
      strong_memoize(:normalized_url) do
        CGI.unescape(Gitlab::UrlSanitizer.sanitize(url))
      end
    end

    def update_mirror(remote_mirror)
      remote_mirror.update_start!

      # LFS objects must be sent first, or the push has dangling pointers
      lfs_status = send_lfs_objects!(remote_mirror)

      response = remote_mirror.update_repository
      failed, failure_message = failure_status(lfs_status, response, remote_mirror)

      # When the issue https://gitlab.com/gitlab-org/gitlab/-/issues/349262 is closed,
      # we can move this block within failure_status.
      if failed
        remote_mirror.mark_as_failed!(failure_message)
      else
        remote_mirror.update_finish!
      end
    end

    def failure_status(lfs_status, response, remote_mirror)
      message = ''
      failed = false
      lfs_sync_failed = false

      if lfs_status&.dig(:status) == :error
        lfs_sync_failed = true
        message += "Error synchronizing LFS files:"
        message += "\n\n#{lfs_status[:message]}\n\n"

        failed = Feature.enabled?(:remote_mirror_fail_on_lfs, project)
      end

      if response.divergent_refs.any?
        message += "Some refs have diverged and have not been updated on the remote:"
        message += "\n\n#{response.divergent_refs.join("\n")}"
        failed = true
      end

      if message.present?
        Gitlab::AppJsonLogger.info(
          message: "Error synching remote mirror",
          project_id: project.id,
          project_path: project.full_path,
          remote_mirror_id: remote_mirror.id,
          lfs_sync_failed: lfs_sync_failed,
          divergent_ref_list: response.divergent_refs
        )
      end

      [failed, message]
    end

    def send_lfs_objects!(remote_mirror)
      return unless project.lfs_enabled?

      # TODO: Support LFS sync over SSH
      # https://gitlab.com/gitlab-org/gitlab/-/issues/249587
      return unless remote_mirror.url =~ %r{\Ahttps?://}i
      return unless remote_mirror.password_auth?

      Lfs::PushService.new(
        project,
        current_user,
        url: remote_mirror.bare_url,
        credentials: remote_mirror.credentials
      ).execute
    end

    def hard_retry_or_fail(mirror, message, tries)
      if tries < MAX_TRIES
        mirror.hard_retry!(message)
      else
        # It's not likely we'll be able to recover from this ourselves, so we'll
        # notify the users of the problem, and don't trigger any sidekiq retries
        # Instead, we'll wait for the next change to try the push again, or until
        # a user manually retries.
        mirror.hard_fail!(message)
      end
    end
  end
end