BlueWallet/ios/Widgets/Shared/WidgetAPI.swift

//
//  WidgetAPI.swift
//  TodayExtension
//
//  Created by Marcos Rodriguez on 11/2/19.

//

import Foundation

struct CurrencyError: LocalizedError {
  var errorDescription: String = "Failed to parse response"
}

var numberFormatter: NumberFormatter {
  let formatter = NumberFormatter()
  formatter.numberStyle = .decimal
  formatter.maximumFractionDigits = 0
  formatter.locale = Locale.current
  return formatter
}

class WidgetAPI {
  static func fetchPrice(currency: String, completion: @escaping ((WidgetDataStore?, Error?) -> Void)) {
    let currencyToFiatUnit = fiatUnit(currency: currency)
    guard let source = currencyToFiatUnit?.source, let endPointKey = currencyToFiatUnit?.endPointKey else { return }

    var urlString: String
    switch source {
    case "Yadio":
      urlString = "https://api.yadio.io/json/\(endPointKey)"
    case "YadioConvert":
      urlString = "https://api.yadio.io/convert/1/BTC/\(endPointKey)"
    case "Exir":
      urlString = "https://api.exir.io/v1/ticker?symbol=btc-irt"
    case "wazirx":
      urlString = "https://api.wazirx.com/api/v2/tickers/btcinr"
    case "Bitstamp":
      urlString = "https://www.bitstamp.net/api/v2/ticker/btc\(endPointKey.lowercased())"
    case "Coinbase":
      urlString = "https://api.coinbase.com/v2/prices/BTC-\(endPointKey.uppercased())/buy"
    case "CoinGecko":
      urlString = "https://api.coingecko.com/api/v3/simple/price?ids=bitcoin&vs_currencies=\(endPointKey.lowercased())"
    case "BNR":
      urlString = "https://www.bnr.ro/nbrfxrates.xml"
    default:
      urlString = "https://api.coindesk.com/v1/bpi/currentprice/\(endPointKey).json"
    }

    guard let url = URL(string:urlString) else { return }

    if source == "BNR" {
 URLSession.shared.dataTask(with: url) { (data, response, error) in
            if let error = error {
                print("Error fetching data: \(error.localizedDescription)")
                completion(nil, error)
                return
            }

            guard let data = data else {
                print("No data received")
                completion(nil, nil)
                return
            }

            // Parse XML data for USD to RON rate
            let parser = XMLParser(data: data)
            let delegate = BNRXMLParserDelegate()
            parser.delegate = delegate
            if parser.parse(), let usdToRonRate = delegate.usdRate {
                // Fetch BTC to USD rate using CoinGecko
                let coinGeckoUrl = URL(string: "https://api.coingecko.com/api/v3/simple/price?ids=bitcoin&vs_currencies=usd")!
                URLSession.shared.dataTask(with: coinGeckoUrl) { (data, _, error) in
                    guard let data = data, error == nil else {
                        completion(nil, error ?? CurrencyError())
                        return
                    }

                    do {
                        if let json = try JSONSerialization.jsonObject(with: data, options: []) as? [String: Any],
                           let bitcoinDict = json["bitcoin"] as? [String: Double],
                           let btcToUsdRate = bitcoinDict["usd"] {
                            let btcToRonRate = btcToUsdRate * usdToRonRate
                            let lastUpdatedString = ISO8601DateFormatter().string(from: Date())
                            let latestRateDataStore = WidgetDataStore(rate: String(btcToRonRate), lastUpdate: lastUpdatedString, rateDouble: btcToRonRate)
                            completion(latestRateDataStore, nil)
                        } else {
                            completion(nil, CurrencyError())
                        }
                    } catch {
                        completion(nil, error)
                    }
                }.resume()
            } else {
                print("Error parsing XML")
                completion(nil, CurrencyError())
            }
        }.resume()
      } else {
        URLSession.shared.dataTask(with: url) { (data, response, error) in
        guard let dataResponse = data,
              let json = (try? JSONSerialization.jsonObject(with: dataResponse, options: .mutableContainers) as? Dictionary<String, Any>),
              error == nil
        else {
          print(error?.localizedDescription ?? "Response Error")
          completion(nil, error)
          return
        }
        
        var latestRateDataStore: WidgetDataStore?
        switch source {
        case "Yadio":
          guard let rateDict = json[endPointKey] as? [String: Any],
                let rateDouble = rateDict["price"] as? Double,
                let lastUpdated = json["timestamp"] as? Int
          else { break }
          let unix = Double(lastUpdated / 1_000)
          let lastUpdatedString = ISO8601DateFormatter().string(from: Date(timeIntervalSince1970: unix))
          latestRateDataStore = WidgetDataStore(rate: String(rateDouble), lastUpdate: lastUpdatedString, rateDouble: rateDouble)
        case "CoinGecko":
          guard let rateDict = json["bitcoin"] as? [String: Any],
                let rateDouble = rateDict[endPointKey.lowercased()] as? Double
          else { break }
          let lastUpdatedString = ISO8601DateFormatter().string(from: Date())
          latestRateDataStore = WidgetDataStore(rate: String(rateDouble), lastUpdate: lastUpdatedString, rateDouble: rateDouble)
        case "YadioConvert":
          guard let rateDict = json as? [String: Any],
                let rateDouble = rateDict["rate"] as? Double,
                let lastUpdated = json["timestamp"] as? Int
          else { break }
          let unix = Double(lastUpdated / 1_000)
          let lastUpdatedString = ISO8601DateFormatter().string(from: Date(timeIntervalSince1970: unix))
          latestRateDataStore = WidgetDataStore(rate: String(rateDouble), lastUpdate: lastUpdatedString, rateDouble: rateDouble)
        case "Exir":
          guard let rateDouble = json["last"] as? Double else { break }
          let rateString = String(rateDouble)
          let lastUpdatedString = ISO8601DateFormatter().string(from: Date())
          latestRateDataStore = WidgetDataStore(rate: rateString, lastUpdate: lastUpdatedString, rateDouble: rateDouble)
        case "Bitstamp":
          guard let rateString = json["last"] as? String, let rateDouble = Double(rateString) else { break }
          let lastUpdatedString = ISO8601DateFormatter().string(from: Date())
          latestRateDataStore = WidgetDataStore(rate: rateString, lastUpdate: lastUpdatedString, rateDouble: rateDouble)
        case "wazirx":
          guard let tickerDict = json["ticker"] as? [String: Any],
                let rateString = tickerDict["buy"] as? String,
                let rateDouble = Double(rateString)
          else { break }
          let lastUpdatedString = ISO8601DateFormatter().string(from: Date())
          latestRateDataStore = WidgetDataStore(rate: rateString, lastUpdate: lastUpdatedString, rateDouble: rateDouble)
        case "Coinbase":
          guard let data = json["data"] as? Dictionary<String, Any>,
                let rateString = data["amount"] as? String,
                let rateDouble = Double(rateString)
          else { break }
          let lastUpdatedString = ISO8601DateFormatter().string(from: Date())
          latestRateDataStore = WidgetDataStore(rate: rateString, lastUpdate: lastUpdatedString, rateDouble: rateDouble)
        default:
          guard let bpi = json["bpi"] as? Dictionary<String, Any>,
                let preferredCurrency = bpi[endPointKey] as? Dictionary<String, Any>,
                let rateString = preferredCurrency["rate"] as? String,
                let rateDouble = preferredCurrency["rate_float"] as? Double,
                let time = json["time"] as? Dictionary<String, Any>,
                let lastUpdatedString = time["updatedISO"] as? String
          else { break }
          latestRateDataStore = WidgetDataStore(rate: rateString, lastUpdate: lastUpdatedString, rateDouble: rateDouble)
        }
        
        if (latestRateDataStore == nil) {
          completion(nil, CurrencyError())
          return
        }
        
        completion(latestRateDataStore, nil)
      }.resume()
    }
  }

  static func getUserPreferredCurrency() -> String {

    guard let userDefaults = UserDefaults(suiteName: UserDefaultsGroupKey.GroupName.rawValue),
          let preferredCurrency = userDefaults.string(forKey: "preferredCurrency")
    else {
      return "USD"
    }

    if preferredCurrency != WidgetAPI.getLastSelectedCurrency() {
      UserDefaults.standard.removeObject(forKey: WidgetData.WidgetCachedDataStoreKey)
      UserDefaults.standard.removeObject(forKey: WidgetData.WidgetDataStoreKey)
      UserDefaults.standard.synchronize()
    }

    return preferredCurrency
  }

  static func getUserPreferredCurrencyLocale() -> String {
    guard let userDefaults = UserDefaults(suiteName: UserDefaultsGroupKey.GroupName.rawValue),
          let preferredCurrency = userDefaults.string(forKey: "preferredCurrencyLocale")
    else {
      return "en_US"
    }
    return preferredCurrency
  }

  static func getLastSelectedCurrency() -> String {
    guard let userDefaults = UserDefaults(suiteName: UserDefaultsGroupKey.GroupName.rawValue), let dataStore = userDefaults.string(forKey: "currency") else {
      return "USD"
    }

    return dataStore
  }

  static func saveNewSelectedCurrency() {
    UserDefaults.standard.setValue(WidgetAPI.getUserPreferredCurrency(), forKey: "currency")
  }

}