private UsedPurchaseWeight ToEntity(UsedPurchaseWeightModel wt, UsedPurchase purchase)
 {
     return(new UsedPurchaseWeight
     {
         Id = wt.Id,
         Colour = wt.Colour,
         Weight = wt.Weight,
         UsedPurchase = purchase
     });
 }
 private UsedPurchaseModel ToModel(UsedPurchase usedPurchase)
 {
     return(new UsedPurchaseModel
     {
         Id = usedPurchase.Id,
         Date = usedPurchase.Date,
         Source = usedPurchase.Source,
         SourceUsername = usedPurchase.SourceUsername,
         OrderNumber = usedPurchase.OrderNumber,
         Price = usedPurchase.Price,
         PaymentMethod = usedPurchase.PaymentMethod,
         Receipt = usedPurchase.Receipt,
         DistanceTravelled = usedPurchase.DistanceTravelled,
         Location = usedPurchase.Location,
         Postage = usedPurchase.Postage,
         Weight = usedPurchase.Weight,
         PricePerKilo = usedPurchase.PricePerKilo,
         CompleteSets = usedPurchase.CompleteSets,
         Notes = usedPurchase.Notes,
         TotalBundleWeight = usedPurchase.Weights.Sum(x => x.Weight / 1000)
     });
 }