package Assignment8

import net.liftweb.json
import net.liftweb.json.DefaultFormats

import java.net.URI
import scala.concurrent.duration.Duration
import scala.concurrent.{Await, Future}
import scala.sys.process._
import scala.util.{Failure, Success}

object Ex2 extends App {
  implicit val ec: scala.concurrent.ExecutionContext = scala.concurrent.ExecutionContext.global
  implicit val formats: DefaultFormats.type = DefaultFormats

  case class Coin(id: String, icon: String, name: String, symbol: String, rank: Int, price: Double, priceBtc: Double, volume: Double, marketCap: Double, availableSupply: Double, totalSupply: Double, fullyDilutedValuation: Double, priceChange1h: Double, priceChange1d: Double, priceChange1w: Double, redditUrl: String, websiteUrl: String, twitterUrl: String, explorers: List[String])
  case class Currency(name: String, rate: Double, symbol: String, imageUrl: String)

  val BITCOIN_TO_USD: String = "https://openapiv1.coinstats.app/coins/bitcoin"
  val USD_TO_CHF: String = "https://openapiv1.coinstats.app/fiats"
  private val API_KEY: String = sys.env.getOrElse("OPENAPI_KEY", "")

  def getUrl(url: String): Future[String] = {
    Future {
      val uri: URI = new URI(url)
      val cmd: String = "curl -s -H 'X-API-KEY: " + API_KEY + "' " + uri.toString
      cmd.!!
    }
  }

  def extractBitcoinToUSDRate(jsonStr: String): Double = {
    val data: Coin = json.parse(jsonStr).extract[Coin]
    return data.price
  }

  def extractUSDToCHFRate(jsonStr: String): Double = {
    val data: List[Currency] = json.parse(jsonStr).extract[List[Currency]]
    return data.find(currency => currency.name == "CHF")
               .map(currency => currency.rate)
               .get
  }

  def getBitcoinToUSD: Future[Double] = {
    getUrl(BITCOIN_TO_USD) map extractBitcoinToUSDRate
  }

  def getUSDToCHF: Future[Double] = {
    getUrl(USD_TO_CHF) map extractUSDToCHFRate
  }

  val f: Future[Double] = for {
    btc2usd <- getBitcoinToUSD
    usd2chf <- getUSDToCHF
  } yield btc2usd * usd2chf

  f onComplete {
    case Success(value) => println(s"1 BTC == $value CHF")
    case Failure(e) => println(s"An error occurred: $e")
  }

  Await.ready(f, Duration.Inf)
}