/**
 * Use Case: SelectAvatarUseCase
 *
 * Handles the business logic for selecting a generated avatar from the options.
 */

import type { IAvatarGenerationRepository } from '../../domain/repositories/IAvatarGenerationRepository';
import type { Logger } from '@core/shared/application';
import type { ISelectAvatarPresenter } from '../presenters/ISelectAvatarPresenter';

export interface SelectAvatarInput {
  requestId: string;
  selectedIndex: number;
}

export interface SelectAvatarResult {
  success: boolean;
  selectedAvatarUrl?: string;
  errorMessage?: string;
}

export interface ISelectAvatarPresenter {
  present(result: SelectAvatarResult): void;
}

export class SelectAvatarUseCase {
  constructor(
    private readonly avatarRepo: IAvatarGenerationRepository,
    private readonly logger: Logger,
  ) {}

  async execute(
    input: SelectAvatarInput,
    presenter: ISelectAvatarPresenter,
  ): Promise<void> {
    try {
      this.logger.info('[SelectAvatarUseCase] Selecting avatar', {
        requestId: input.requestId,
        selectedIndex: input.selectedIndex,
      });

      const request = await this.avatarRepo.findById(input.requestId);

      if (!request) {
        presenter.present({
          success: false,
          errorMessage: 'Avatar generation request not found',
        });
        return;
      }

      if (request.status !== 'completed') {
        presenter.present({
          success: false,
          errorMessage: 'Avatar generation is not completed yet',
        });
        return;
      }

      request.selectAvatar(input.selectedIndex);
      await this.avatarRepo.save(request);

      const selectedAvatarUrl = request.selectedAvatarUrl;

      presenter.present({
        success: true,
        selectedAvatarUrl,
      });

      this.logger.info('[SelectAvatarUseCase] Avatar selected successfully', {
        requestId: input.requestId,
        selectedAvatarUrl,
      });

    } catch (error) {
      this.logger.error('[SelectAvatarUseCase] Error selecting avatar', {
        error: error instanceof Error ? error.message : 'Unknown error',
        requestId: input.requestId,
      });

      presenter.present({
        success: false,
        errorMessage: 'Internal error occurred while selecting avatar',
      });
    }
  }
}