class ProfilePointer {
  final String pubkey;
  final List<String>? relays;

  ProfilePointer({required this.pubkey, this.relays});
}

/// EventPointer is a class that represents a pointer to an event in the Nostr protocol.
class EventPointer {
  /// The unique identifier of the event.
  final String id;

  /// A list of relays to use to reach the event.
  final List<String>? relays;

  /// The author of the event.
  final String? author;

  /// Constructs an EventPointer object with the given properties.
  ///
  /// The [id] parameter is required and represents the unique identifier of the event.
  /// The [relays] parameter is optional and represents a list of relays to use to reach the event.
  /// The [author] parameter is optional and represents the author of the event.
  EventPointer({required this.id, this.relays, this.author});
}

/// A pointer to a Nostr address.
///
/// The [AddressPointer] class is used to store information about a Nostr address
/// including an identifier, a public key, a kind, and a list of relays.
class AddressPointer {
  /// The identifier for the address.
  final String identifier;

  /// The public key associated with the address.
  final String pubkey;

  /// The kind of the address.
  final int kind;

  /// The list of relays associated with the address.
  final List<String>? relays;

  /// Creates a new [AddressPointer] instance.
  ///
  /// The [identifier], [pubkey], and [kind] parameters are required.
  /// The [relays] parameter is optional and can be `null`.
  AddressPointer({
    required this.identifier,
    required this.pubkey,
    required this.kind,
    this.relays,
  });
}

class SignatureVerificationException implements Exception {
  final String message;

  SignatureVerificationException(this.message);

  @override
  String toString() => 'SignatureVerificationException: $message';
}

class ChecksumVerificationException implements Exception {
  final String message;
  ChecksumVerificationException(this.message);

  @override
  String toString() => 'ChecksumVerificationException: $message';
}