class CurrencyRate { final int id; final String currency; final String symbol; final double rate; final int coinPrecision; const CurrencyRate({ required this.id, required this.currency, required this.symbol, required this.rate, required this.coinPrecision, }); factory CurrencyRate.fromJson(Map json) { return CurrencyRate( id: (json['id'] as num?)?.toInt() ?? 0, currency: json['currency'] as String? ?? '', symbol: json['symbol'] as String? ?? '\$', rate: double.tryParse(json['rate']?.toString() ?? '') ?? 1.0, coinPrecision: (json['coinPrecision'] as num?)?.toInt() ?? 2, ); } String get displayName => '$currency $symbol'; }