import type { League } from '@gridpilot/racing/domain/entities/League';
import type {
  IAllLeaguesWithCapacityPresenter,
  LeagueWithCapacityViewModel,
  AllLeaguesWithCapacityViewModel,
} from '@gridpilot/racing/application/presenters/IAllLeaguesWithCapacityPresenter';

export class AllLeaguesWithCapacityPresenter implements IAllLeaguesWithCapacityPresenter {
  private viewModel: AllLeaguesWithCapacityViewModel | null = null;

  present(
    leagues: League[],
    memberCounts: Map<string, number>
  ): AllLeaguesWithCapacityViewModel {
    const leagueItems: LeagueWithCapacityViewModel[] = leagues.map((league) => {
      const usedSlots = memberCounts.get(league.id) ?? 0;

      // Ensure we never expose an impossible state like 26/24:
      // clamp maxDrivers to at least usedSlots at the application boundary.
      const configuredMax = league.settings.maxDrivers ?? usedSlots;
      const safeMaxDrivers = Math.max(configuredMax, usedSlots);

      const base: LeagueWithCapacityViewModel = {
        id: league.id,
        name: league.name,
        description: league.description,
        ownerId: league.ownerId,
        settings: {
          ...league.settings,
          maxDrivers: safeMaxDrivers,
        },
        createdAt: league.createdAt.toISOString(),
        usedSlots,
      };

      if (!league.socialLinks) {
        return base;
      }

      const socialLinks: NonNullable<LeagueWithCapacityViewModel['socialLinks']> = {};

      if (league.socialLinks.discordUrl) {
        socialLinks.discordUrl = league.socialLinks.discordUrl;
      }
      if (league.socialLinks.youtubeUrl) {
        socialLinks.youtubeUrl = league.socialLinks.youtubeUrl;
      }
      if (league.socialLinks.websiteUrl) {
        socialLinks.websiteUrl = league.socialLinks.websiteUrl;
      }

      if (Object.keys(socialLinks).length === 0) {
        return base;
      }

      return {
        ...base,
        socialLinks,
      };
    });

    this.viewModel = {
      leagues: leagueItems,
      totalCount: leagueItems.length,
    };

    return this.viewModel;
  }

  getViewModel(): AllLeaguesWithCapacityViewModel {
    if (!this.viewModel) {
      throw new Error('Presenter has not been called yet');
    }
    return this.viewModel;
  }
}