/// <summary>
/// Fetches the offers for the desired currency.
/// <remarks>
/// Example: Scanner.BuyingType = ChaosOrb, selling Type = Fusings
/// will return all offers where the owner is buying chaos for fusings.
/// </remarks>
/// </summary>
/// <param name="selling">what currency the other person is selling</param>
/// <returns></returns>
public async Task <(CurrencyType, List <Offer>)> FetchOffers(CurrencyType selling, string league)
{
_logger.Info($"Fetching Offers on {this}");
var offers = await _provider.GetOffers(BuyingType, selling, league);
return(BuyingType, offers);
}