viewMode.swift

let onUnit = BehaviorRelay(value: "")
let onTotal = BehaviorRelay(value: "")
let onPriceUpdated = BehaviorRelay<ProductPriceEntity?>(value: nil)
let onQuantity = BehaviorRelay(value: 1)
var prices: [ProductPriceEntity] = []

  Observable.combineLatest(onUnit, onQuantity).flatMapLatest{[weak self] (unit, qty) -> Observable<Void> in
      guard let self = self else { return Observable.just(()) } 

      let price = self.unitPrices.value[unit]?.filter { price in
          let min = price.minCount ?? 1
          let max = price.maxCount ?? 1
          if max < min {
              return min...max ~= qty
          }else{
              return false
          }
      }.first

      //Calculate Item Total
      var total = 0
      var currency = ""

      if let priceData = price, qty >= priceData.minCount ?? 1 && qty <= priceData.maxCount ?? 1{

          let cents = priceData.price?.cents ?? 0
          currency = priceData.price?.currencyIso ?? ""
          total = cents * qty

          self.pricePerUnit.accept("\(StringUtils.format(price: cents, currencyCode: currency))  /\(priceData.unit ?? "")")

          self.priceBreakDown.accept("\(priceData.minCount ?? 1) - \(priceData.maxCount ?? 1) \(priceData.unit ?? ""): \(StringUtils.format(price: priceData.price?.cents ?? 0, currencyCode: priceData.price?.currencyIso ?? "")) / \(priceData.unit ?? "")")

      }else{
          self.pricePerUnit.accept(R.string.localizable.ordersRequestTitle.key.localized())
          total = 0
      }

      if total == 0 {
          self.pricePerUnit.accept(R.string.localizable.ordersRequestTitle.key.localized())
          self.priceBreakDown.accept("-")
          self.onTotal.accept(R.string.localizable.orderEditPriceTBC.key.localized())
      }else{
          self.onTotal.accept(StringUtils.format(price: total, currencyCode: currency))
      }

      if let data = price {
          self.onPriceUpdated.accept(data)
      }

      return Observable.just(())
  }.subscribe(onNext: {[weak self](_) in

  }).disposed(by: rx.disposeBag)