import 'dart:typed_data';

enum IdentityStatus { unverified, pending, approved, changesRequested, denied }

enum ReviewReason {
  passportUnreadable,
  selfieUnreadable,
  passportExpired,
  unableToVerify,
}

enum PhotoKind { passport, selfie }

enum KycError {
  unavailable,
  internal,
  permission,
  format,
  tooLarge,
  unreadable,
  tooSmall,
  incomplete,
  sessionExpired,
  rateLimited,
  conflict,
}

class KycException implements Exception {
  const KycException(this.code);
  final KycError code;
}

class Identity {
  const Identity({
    required this.status,
    this.reason,
    this.submissionId,
    this.simulated = false,
    this.profile = const IdentityProfile(),
    this.upgradePending = false,
  });
  final IdentityStatus status;
  final ReviewReason? reason;
  final String? submissionId;
  final bool simulated;
  final IdentityProfile profile;
  final bool upgradePending;
  bool get canSubmit =>
      status == IdentityStatus.unverified ||
      status == IdentityStatus.changesRequested;
}

/// Customer assertions awaiting human review, distinct from a verified identity.
class IdentityProfile {
  const IdentityProfile({
    this.fullName = '',
    this.dateOfBirth = '',
    this.residenceCountry = '',
  });
  final String fullName, dateOfBirth, residenceCountry;
  bool get isComplete {
    final date = DateTime.tryParse(dateOfBirth);
    return fullName.trim().isNotEmpty &&
        fullName.length <= 200 &&
        RegExp(r'^\d{4}-\d{2}-\d{2}$').hasMatch(dateOfBirth) &&
        date != null &&
        date.toIso8601String().startsWith(dateOfBirth) &&
        date.isBefore(DateTime.now()) &&
        RegExp(r'^[A-Z]{2}$').hasMatch(residenceCountry);
  }
}

/// Ephemeral image data only. Never serialize this model into storage or telemetry.
class Photo {
  Photo(Uint8List bytes)
    : bytes = Uint8List.fromList(bytes).asUnmodifiableView();
  final Uint8List bytes;
}