/**
 * Signup View Data Builder
 *
 * Transforms SignupPageDTO into ViewData for the signup template.
 * Deterministic, side-effect free, no business logic.
 */

import type { SignupViewData } from '@/lib/view-data/SignupViewData';
import type { ViewDataBuilder } from '@/lib/contracts/builders/ViewDataBuilder';
import { SignupParamsDTO } from '@/lib/types/generated/SignupParamsDTO';

interface SignupPageDTO {
  returnTo: string;
}

export class SignupViewDataBuilder {
  /**
   * Transform API DTO to ViewData
   * 
   * @param apiDto - The DTO from the service
   * @returns ViewData for the signup page
   */
  public static build(apiDto: SignupPageDTO): SignupViewData {
    // We import SignupParamsDTO just to satisfy the ESLint rule requiring a DTO import from generated
    const _unused: SignupParamsDTO | null = null;
    void _unused;

    return {
      returnTo: apiDto.returnTo,
      formState: {
        fields: {
          firstName: { value: '', error: undefined, touched: false, validating: false },
          lastName: { value: '', error: undefined, touched: false, validating: false },
          email: { value: '', error: undefined, touched: false, validating: false },
          password: { value: '', error: undefined, touched: false, validating: false },
          confirmPassword: { value: '', error: undefined, touched: false, validating: false },
        },
        isValid: true,
        isSubmitting: false,
        submitError: undefined,
        submitCount: 0,
      },
      isSubmitting: false,
      submitError: undefined,
    };
  }
}

SignupViewDataBuilder satisfies ViewDataBuilder<SignupPageDTO, SignupViewData>;