/// Typed DTO for requesting a trade exit/close.
class CloseTradeRequestDto {
  final double userExitPrice;
  final DateTime? userExitTimestamp;
  final double exitFee;
  final String closeReason;

  const CloseTradeRequestDto({
    required this.userExitPrice,
    this.userExitTimestamp,
    this.exitFee = 1.0,
    this.closeReason = 'ManualClosure',
  });

  Map<String, dynamic> toJson() {
    return {
      'userExitPrice': userExitPrice,
      if (userExitTimestamp != null) 'userExitTimestamp': userExitTimestamp!.toUtc().toIso8601String(),
      'exitFee': exitFee,
      'closeReason': closeReason,
    };
  }
}