# frozen_string_literal: true

module DraftNotes
  class PublishService < DraftNotes::BaseService
    def execute(draft: nil, executing_user: nil)
      executing_user ||= current_user

      return error('Not allowed to create notes') unless can?(executing_user, :create_note, merge_request)

      review = nil
      if draft
        publish_draft_note(draft, executing_user)
      else
        review = create_review(executing_user)
        merge_request_activity_counter.track_publish_review_action(user: current_user) if review
      end

      handle_notifications(current_user, merge_request, review) if draft || review
      success
    rescue ActiveRecord::RecordInvalid => e
      message = "Unable to save #{e.record.class.name}: #{e.record.errors.full_messages.join(', ')} "
      error(message)
    end

    private

    def publish_draft_note(draft, executing_user)
      create_note_from_draft(draft, executing_user)
      draft.delete
    end

    def create_review(executing_user)
      return if draft_notes.blank?

      review = Review.create!(author: current_user, merge_request: merge_request, project: project)

      created_notes = draft_notes.filter_map do |draft_note|
        next unless draft_note.note.present?

        draft_note.review = review
        create_note_from_draft(
          draft_note,
          executing_user,
          skip_capture_diff_note_position: true,
          skip_keep_around_commits: true,
          skip_merge_status_trigger: true
        )
      end

      capture_diff_note_positions(created_notes)
      keep_around_commits(created_notes)
      draft_notes.delete_all
      GraphqlTriggers.merge_request_merge_status_updated(merge_request)
      after_publish

      review
    end

    def create_note_from_draft(draft, executing_user, skip_capture_diff_note_position: false, skip_keep_around_commits: false, skip_merge_status_trigger: false)
      # Make sure the diff file is unfolded in order to find the correct line
      # codes.
      draft.diff_file&.unfold_diff_lines(draft.original_position)

      note_params = draft.publish_params.merge(skip_keep_around_commits: skip_keep_around_commits)
      note = Notes::CreateService.new(project, current_user, note_params).execute(
        skip_capture_diff_note_position: skip_capture_diff_note_position,
        skip_merge_status_trigger: skip_merge_status_trigger,
        executing_user: executing_user
      )

      set_discussion_resolve_status(note, draft)
      note
    end

    def set_discussion_resolve_status(note, draft_note)
      return unless draft_note.discussion_id.present?

      discussion = note.discussion

      if draft_note.resolve_discussion && discussion.can_resolve?(current_user)
        discussion.resolve!(current_user)
      else
        discussion.unresolve!
      end
    end

    def capture_diff_note_positions(notes)
      paths = notes.flat_map do |note|
        note.diff_file&.paths if note.diff_note?
      end

      return if paths.empty?

      capture_service = Discussions::CaptureDiffNotePositionService.new(merge_request, paths.compact)

      notes.each do |note|
        capture_service.execute(note.discussion) if note.diff_note? && note.start_of_discussion?
      end
    end

    def keep_around_commits(notes)
      shas = notes.flat_map do |note|
        note.shas if note.diff_note?
      end.uniq

      # We are allowing this since gitaly call will be created for each sha and
      # even though they're unique, there will still be multiple Gitaly calls.
      Gitlab::GitalyClient.allow_n_plus_1_calls do
        project.repository.keep_around(*shas, source: self.class.name)
      end
    end

    def after_publish
      merge_request.assignees.each(&:invalidate_merge_request_cache_counts)
    end

    def handle_notifications(current_user, merge_request, review)
      create_draft_published_event(merge_request, current_user, review)

      MergeRequests::ResolvedDiscussionNotificationService
        .new(project: project, current_user: current_user)
        .execute(merge_request, send_notifications: false)
    end

    def create_draft_published_event(merge_request, current_user, review)
      review_id = review&.id
      data = { current_user_id: current_user.id, merge_request_id: merge_request.id }
      data[:review_id] = review_id if review_id

      Gitlab::EventStore.publish(
        MergeRequests::DraftNotePublishedEvent.new(
          data: data
        )
      )
    end
  end
end

DraftNotes::PublishService.prepend_mod
