import Foundation

class Balance {
    static func formatBalance(_ balance: Decimal, toUnit: BitcoinUnit, withFormatting: Bool = false, completion: @escaping (String) -> Void) {
      switch toUnit {
      case .sats:
        if withFormatting {
          completion(NumberFormatter.localizedString(from: balance as NSNumber, number: .decimal) + " SATS")
        } else {
          completion("\(balance) SATS")
        }
      case .localCurrency:
        fetchLocalCurrencyEquivalent(satoshi: balance, completion: completion)
        
      default:
        let value = balance / Decimal(100_000_000)
        completion("\(value) BTC") // Localize unit names as needed.
      }
    }

    private static func fetchLocalCurrencyEquivalent(satoshi: Decimal, completion: @escaping (String) -> Void) {
      
        let currency = Currency.getUserPreferredCurrency() // Ensure this method retrieves the correct currency code.
        MarketAPI.fetchPrice(currency: currency) { dataStore, error in
            DispatchQueue.main.async {
                guard let dataStore = dataStore, error == nil else {
                    completion("Error: \(error?.localizedDescription ?? "Unknown error")")
                    return
                }
                let rate = Decimal(string: dataStore.rate) ?? Decimal(0)
                let convertedAmount = (satoshi / Decimal(100_000_000)) * rate
                completion("\(convertedAmount) \(currency)")
            }
        }
    }
}

extension Decimal {
  func formatted(as unit: BitcoinUnit, withFormatting: Bool = false) -> String {
        switch unit {
        case .sats:
            return withFormatting ? NumberFormatter.localizedString(from: self as NSNumber, number: .decimal) + " SATS" : "\(self) SATS"
        case .localCurrency:
            let userDefaults = UserDefaults(suiteName: UserDefaultsGroupKey.GroupName.rawValue)
            if let widgetData = userDefaults?.object(forKey: MarketData.string) as? Data,
               let marketData = try? JSONDecoder().decode(MarketData.self, from: widgetData) {
                let rate = Decimal(marketData.rate)
                let convertedAmount = (self / Decimal(100_000_000)) * rate
                return "\(convertedAmount) \(Currency.getUserPreferredCurrency())"
            } else {
                return "N/A"
            }
        default:
            let value = self / Decimal(100_000_000)
            return "\(value) BTC"
        }
    }
}