import type {
  IAllLeaguesWithCapacityAndScoringPresenter,
  LeagueEnrichedData,
  LeagueSummaryViewModel,
  AllLeaguesWithCapacityAndScoringViewModel,
} from '@gridpilot/racing/application/presenters/IAllLeaguesWithCapacityAndScoringPresenter';

export class AllLeaguesWithCapacityAndScoringPresenter implements IAllLeaguesWithCapacityAndScoringPresenter {
  private viewModel: AllLeaguesWithCapacityAndScoringViewModel | null = null;

  reset(): void {
    this.viewModel = null;
  }

  present(enrichedLeagues: LeagueEnrichedData[]): void {
    const leagueItems: LeagueSummaryViewModel[] = enrichedLeagues.map((data) => {
      const { league, usedDriverSlots, season, scoringConfig, game, preset } = data;

      const configuredMaxDrivers = league.settings.maxDrivers ?? usedDriverSlots;
      const safeMaxDrivers = Math.max(configuredMaxDrivers, usedDriverSlots);

      const structureSummary = `Solo • ${safeMaxDrivers} drivers`;

      const qualifyingMinutes = 30;
      const mainRaceMinutes =
        typeof league.settings.sessionDuration === 'number'
          ? league.settings.sessionDuration
          : 40;
      const timingSummary = `${qualifyingMinutes} min Quali • ${mainRaceMinutes} min Race`;

      let scoringPatternSummary: string | null = null;
      let scoringSummary: LeagueSummaryViewModel['scoring'];

      if (season && scoringConfig && game) {
        const dropPolicySummary =
          preset?.dropPolicySummary ?? this.deriveDropPolicySummary(scoringConfig);
        const primaryChampionshipType =
          preset?.primaryChampionshipType ??
          (scoringConfig.championships[0]?.type ?? 'driver');

        const scoringPresetName = preset?.name ?? 'Custom';
        scoringPatternSummary = `${scoringPresetName} • ${dropPolicySummary}`;

        scoringSummary = {
          gameId: game.id,
          gameName: game.name,
          primaryChampionshipType,
          scoringPresetId: scoringConfig.scoringPresetId ?? 'custom',
          scoringPresetName,
          dropPolicySummary,
          scoringPatternSummary,
        };
      } else {
        const dropPolicySummary = 'All results count';
        const scoringPresetName = 'Custom';
        scoringPatternSummary = scoringPatternSummary ?? `${scoringPresetName} • ${dropPolicySummary}`;

        scoringSummary = {
          gameId: 'unknown',
          gameName: 'Unknown',
          primaryChampionshipType: 'driver',
          scoringPresetId: 'custom',
          scoringPresetName,
          dropPolicySummary,
          scoringPatternSummary,
        };
      }

      const base: LeagueSummaryViewModel = {
        id: league.id,
        name: league.name,
        description: league.description,
        ownerId: league.ownerId,
        createdAt: league.createdAt.toISOString(),
        maxDrivers: safeMaxDrivers,
        usedDriverSlots,
        // Team capacity is not yet modeled here; use zero for now to satisfy strict typing.
        maxTeams: 0,
        usedTeamSlots: 0,
        structureSummary,
        scoringPatternSummary: scoringPatternSummary ?? '',
        timingSummary,
        scoring: scoringSummary,
      };

      return base;
    });

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

  getViewModel(): AllLeaguesWithCapacityAndScoringViewModel | null {
    return this.viewModel;
  }

  private deriveDropPolicySummary(config: {
    championships: Array<{
      dropScorePolicy: { strategy: string; count?: number; dropCount?: number };
    }>;
  }): string {
    const championship = config.championships[0];
    if (!championship) {
      return 'All results count';
    }

    const policy = championship.dropScorePolicy;
    if (!policy || policy.strategy === 'none') {
      return 'All results count';
    }

    if (policy.strategy === 'bestNResults' && typeof policy.count === 'number') {
      return `Best ${policy.count} results count`;
    }

    if (
      policy.strategy === 'dropWorstN' &&
      typeof policy.dropCount === 'number'
    ) {
      return `Worst ${policy.dropCount} results are dropped`;
    }

    return 'Custom drop score rules';
  }
}