import 'package:shuffle/core/l10n/l10n.dart';
import 'package:shuffle/features/auth/domain/auth_failure.dart';

/// User-facing text of an [AuthFailure] (Spec #1 § 4.4, texts from
/// `docs/design/auth-screens.md`).
///
/// `emailSendLimited` has no text of its own: screens treat it as success
/// (F12) or convert it to `rateLimited` beforehand.
String authFailureMessage(AppLocalizations l10n, AuthFailure failure) =>
    switch (failure) {
      InvalidCredentials() => l10n.authErrorInvalidCredentials,
      EmailNotConfirmed() => l10n.authErrorEmailNotConfirmed,
      EmailSendLimited() || RateLimited() => l10n.authErrorRateLimited,
      WeakPassword(:final reasons) => weakPasswordMessage(l10n, reasons),
      SamePassword() => l10n.authErrorSamePassword,
      LinkInvalidOrExpired() => l10n.authErrorLinkInvalidOrExpired,
      InvalidEmail() => l10n.authErrorEmailInvalid,
      RegistrationRejected() => l10n.authErrorRegistrationRejected,
      NetworkFailure() => l10n.authErrorNetwork,
      Unexpected() => l10n.authErrorUnexpected,
    };

/// One sentence per distinct reason; an empty list gets the generic text.
String weakPasswordMessage(
  AppLocalizations l10n,
  List<WeakPasswordReason> reasons,
) {
  final texts = <String>{
    for (final reason in reasons)
      switch (reason) {
        WeakPasswordReason.length => l10n.authErrorWeakPasswordLength,
        WeakPasswordReason.pwned => l10n.authErrorWeakPasswordPwned,
        WeakPasswordReason.characters ||
        WeakPasswordReason.unknown => l10n.authErrorWeakPasswordCharacters,
      },
  };
  return texts.isEmpty ? l10n.authErrorWeakPasswordCharacters : texts.join(' ');
}