# frozen_string_literal: true

# Projects::TransferService class
#
# Used to transfer a project to another namespace
#
# Ex.
#   # Move project to namespace by user
#   Projects::TransferService.new(project, user).execute(namespace)
#
module Projects
  class TransferService < BaseService
    include Gitlab::ShellAdapter
    TransferError = Class.new(StandardError)

    def execute(new_namespace)
      @new_namespace = new_namespace

      if @new_namespace.blank?
        raise TransferError, s_('TransferProject|Please select a new namespace for your project.')
      end

      if @new_namespace.id == project.namespace_id
        raise TransferError, s_('TransferProject|Project is already in this namespace.')
      end

      unless allowed_transfer_project?(current_user, project)
        raise TransferError, s_("TransferProject|You don't have permission to transfer this project.")
      end

      unless allowed_to_transfer_to_namespace?(current_user, @new_namespace)
        raise TransferError, s_("TransferProject|You don't have permission to transfer projects into that namespace.")
      end

      transfer(project)

      current_user.invalidate_personal_projects_count

      true
    rescue Projects::TransferService::TransferError => ex
      project.reset
      project.errors.add(:new_namespace, ex.message)
      false
    end

    private

    attr_reader :old_path, :new_path, :new_namespace, :old_namespace

    # rubocop: disable CodeReuse/ActiveRecord
    def transfer(project)
      @old_path = project.full_path
      @old_group = project.group
      @new_path = File.join(@new_namespace.try(:full_path) || '', project.path)
      @old_namespace = project.namespace

      if Project.where(namespace_id: @new_namespace.try(:id)).where('path = ? or name = ?', project.path, project.name).exists?
        raise TransferError, s_("TransferProject|Project with same name or path in target namespace already exists")
      end

      if project.has_container_registry_tags?
        # We currently don't support renaming repository if it contains tags in container registry
        raise TransferError, s_('TransferProject|Project cannot be transferred, because tags are present in its container registry')
      end

      if project.has_packages?(:npm) && !new_namespace_has_same_root?(project)
        raise TransferError, s_("TransferProject|Root namespace can't be updated if project has NPM packages")
      end

      proceed_to_transfer
    end
    # rubocop: enable CodeReuse/ActiveRecord

    def new_namespace_has_same_root?(project)
      new_namespace.root_ancestor == project.namespace.root_ancestor
    end

    def proceed_to_transfer
      Project.transaction do
        project.expire_caches_before_rename(@old_path)

        # Apply changes to the project
        update_namespace_and_visibility(@new_namespace)
        project.reconcile_shared_runners_setting!
        project.save!

        # Notifications
        project.send_move_instructions(@old_path)

        # Directories on disk
        move_project_folders(project)

        transfer_missing_group_resources(@old_group)

        # Move uploads
        move_project_uploads(project)

        update_integrations

        remove_paid_features

        project.old_path_with_namespace = @old_path

        update_repository_configuration(@new_path)

        remove_issue_contacts

        execute_system_hooks
      end

      update_pending_builds

      post_update_hooks(project)
    rescue Exception # rubocop:disable Lint/RescueException
      rollback_side_effects
      raise
    ensure
      refresh_permissions
    end

    # Overridden in EE
    def post_update_hooks(project)
      ensure_personal_project_owner_membership(project)
    end

    # Overridden in EE
    def remove_paid_features
    end

    def transfer_missing_group_resources(group)
      Labels::TransferService.new(current_user, group, project).execute

      Milestones::TransferService.new(current_user, group, project).execute
    end

    def allowed_transfer_project?(current_user, project)
      current_user.can?(:change_namespace, project)
    end

    def allowed_to_transfer_to_namespace?(current_user, namespace)
      current_user.can?(:transfer_projects, namespace)
    end

    def update_namespace_and_visibility(to_namespace)
      # Apply new namespace id and visibility level
      project.namespace = to_namespace
      project.visibility_level = to_namespace.visibility_level unless project.visibility_level_allowed_by_group?
    end

    def update_repository_configuration(full_path)
      project.set_full_path(gl_full_path: full_path)
      project.track_project_repository
    end

    def ensure_personal_project_owner_membership(project)
      # In case of personal projects, we want to make sure that
      # a membership record with `OWNER` access level exists for the owner of the namespace.
      return unless project.personal?

      namespace_owner = project.namespace.owner
      existing_membership_record = project.member(namespace_owner)

      return if existing_membership_record.present? && existing_membership_record.access_level == Gitlab::Access::OWNER

      project.add_owner(namespace_owner)
    end

    def refresh_permissions
      # This ensures we only schedule 1 job for every user that has access to
      # the namespaces.
      user_ids = @old_namespace.user_ids_for_project_authorizations |
        @new_namespace.user_ids_for_project_authorizations

      AuthorizedProjectUpdate::ProjectRecalculateWorker.perform_async(project.id)

      # Until we compare the inconsistency rates of the new specialized worker and
      # the old approach, we still run AuthorizedProjectsWorker
      # but with some delay and lower urgency as a safety net.
      UserProjectAccessChangedService.new(user_ids).execute(
        blocking: false,
        priority: UserProjectAccessChangedService::LOW_PRIORITY
      )
    end

    def rollback_side_effects
      rollback_folder_move
      project.reset
      update_namespace_and_visibility(@old_namespace)
      update_repository_configuration(@old_path)
    end

    def rollback_folder_move
      return if project.hashed_storage?(:repository)

      move_repo_folder(@new_path, @old_path)
      move_repo_folder(new_wiki_repo_path, old_wiki_repo_path)
      move_repo_folder(new_design_repo_path, old_design_repo_path)
    end

    def move_repo_folder(from_name, to_name)
      gitlab_shell.mv_repository(project.repository_storage, from_name, to_name)
    end

    def execute_system_hooks
      system_hook_service.execute_hooks_for(project, :transfer)
    end

    def move_project_folders(project)
      return if project.hashed_storage?(:repository)

      # Move main repository
      unless move_repo_folder(@old_path, @new_path)
        raise TransferError, s_("TransferProject|Cannot move project")
      end

      # Disk path is changed; we need to ensure we reload it
      project.reload_repository!

      # Move wiki and design repos also if present
      move_repo_folder(old_wiki_repo_path, new_wiki_repo_path)
      move_repo_folder(old_design_repo_path, new_design_repo_path)
    end

    def move_project_uploads(project)
      return if project.hashed_storage?(:attachments)

      Gitlab::UploadsTransfer.new.move_project(
        project.path,
        @old_namespace.full_path,
        @new_namespace.full_path
      )
    end

    def old_wiki_repo_path
      "#{old_path}#{::Gitlab::GlRepository::WIKI.path_suffix}"
    end

    def new_wiki_repo_path
      "#{new_path}#{::Gitlab::GlRepository::WIKI.path_suffix}"
    end

    def old_design_repo_path
      "#{old_path}#{::Gitlab::GlRepository::DESIGN.path_suffix}"
    end

    def new_design_repo_path
      "#{new_path}#{::Gitlab::GlRepository::DESIGN.path_suffix}"
    end

    def update_integrations
      project.integrations.with_default_settings.delete_all
      Integration.create_from_active_default_integrations(project, :project_id)
    end

    def update_pending_builds
      ::Ci::PendingBuilds::UpdateProjectWorker.perform_async(project.id, pending_builds_params)
    end

    def pending_builds_params
      {
        namespace_id: new_namespace.id,
        namespace_traversal_ids: new_namespace.traversal_ids
      }
    end

    def remove_issue_contacts
      return unless @old_group&.root_ancestor != @new_namespace&.root_ancestor

      CustomerRelations::IssueContact.delete_for_project(project.id)
    end
  end
end

Projects::TransferService.prepend_mod_with('Projects::TransferService')