Fixes to ordering screen.

prs.desktop/Panels/Stock Forecast/OrderScreen/StockForecastOrderingGrid.cs

@@ -688,25 +688,32 @@ public class StockForecastOrderingGrid : DynamicItemsListGrid<StockOrderingItem>
         }
     }
 
-    private double CalculateSupplierProductRequiredQuantity(StockOrderingItem item, SupplierProduct supplierProduct)
+    /// <summary>
+    /// Calculate the number of units of the given <paramref name="supplierProduct"/> are needed to fill the given item.
+    /// </summary>
+    /// <remarks>
+    /// If we are doing breakups, and <paramref name="useRequiredQuantity"/> is <see langword="true"/>, then we use the <see cref="StockOrderingItem.GetJobRequiredQuantities"/>; otherwise, we use <see cref="StockForecastOrderingItemQuantity.Breakups"/>.
+    /// </remarks>
+    /// <param name="item"></param>
+    /// <param name="supplierProduct"></param>
+    /// <returns></returns>
+    private double CalculateSupplierProductRequiredQuantity(StockOrderingItem item, SupplierProduct supplierProduct, bool useRequiredQuantity)
     {
         var supplierIdx = Suppliers.WithIndex().FirstOrDefault(x => x.Value.ID == supplierProduct.SupplierLink.ID).Key;
         var qty = item.GetQuantity(supplierIdx);
-        var req = OrderType == StockForecastOrderingType.StockOrder ? item.RequiredQuantity : qty.Breakups.Sum(x => x.Value);
+        var req = OrderType == StockForecastOrderingType.StockOrder
+            ? item.RequiredQuantity
+            : (useRequiredQuantity ? item.GetJobRequiredQuantities().Sum(x => x.Value) : qty.Breakups.Sum(x => x.Value));
 
         var d = new StockDimensions();
         d.CopyFrom(supplierProduct.Dimensions);
         var result = DimensionUtils.ConvertDimensions(d, 1.0, (f,c) => Client.Query(f,c));
-        req = Math.Ceiling(req / result);
+        req /= result;
         return req;
     }
 
     private SupplierProduct? SelectSupplierProduct(IEnumerable<SupplierProduct> supplierProducts, StockOrderingItem item)
     {
-        double DimensionsRatio(SupplierProduct x)
-        {
-            return item.Dimensions.Value / (x.Dimensions.Value.IsEffectivelyEqual(0.0) ? (item.Dimensions.Value.IsEffectivelyEqual(0.0) ? 1.0 : item.Dimensions.Value) : x.Dimensions.Value);
-        }
         switch (item.OrderStrategy)
         {
             case SupplierProductOrderStrategy.Exact:
@@ -715,13 +722,13 @@ public class StockForecastOrderingGrid : DynamicItemsListGrid<StockOrderingItem>
                            .MinBy(x => x.CostPrice);
             
             case SupplierProductOrderStrategy.LowestOverallPrice:
-                return supplierProducts.MinBy(x => x.CostPrice * Math.Ceiling(CalculateSupplierProductRequiredQuantity(item, x) * DimensionsRatio(x)));
+                return supplierProducts.MinBy(x => x.CostPrice * Math.Ceiling(CalculateSupplierProductRequiredQuantity(item, x, true)));
 
             case SupplierProductOrderStrategy.LowestUnitPrice:
-                return supplierProducts.MinBy(x => x.CostPrice * DimensionsRatio(x));
+                return supplierProducts.MinBy(x => x.CostPrice / x.Dimensions.Value);
             
             case SupplierProductOrderStrategy.LowestOverstock:
-                return supplierProducts.MinBy(x => x.Dimensions.Value * Math.Ceiling(CalculateSupplierProductRequiredQuantity(item, x) * DimensionsRatio(x)));
+                return supplierProducts.MinBy(x => x.Dimensions.Value * Math.Ceiling(CalculateSupplierProductRequiredQuantity(item, x, true)));
                 
             default:
                 return null;
@@ -730,12 +737,7 @@ public class StockForecastOrderingGrid : DynamicItemsListGrid<StockOrderingItem>
 
     private double GetRequiredQuantity(StockOrderingItem item, SupplierProduct supplierProduct)
     {
-        var requiredQuantity = CalculateSupplierProductRequiredQuantity(item, supplierProduct);
-
-        double DimensionsRatio(SupplierProduct x)
-        {
-            return item.Dimensions.Value / (x.Dimensions.Value.IsEffectivelyEqual(0.0) ? (item.Dimensions.Value.IsEffectivelyEqual(0.0) ? 1.0 : item.Dimensions.Value) : x.Dimensions.Value);
-        }
+        var requiredQuantity = CalculateSupplierProductRequiredQuantity(item, supplierProduct, useRequiredQuantity: false);
 
         var _strategy = item.CustomStrategy
             ? SupplierProductOrderStrategy.LowestOverstock
@@ -750,7 +752,7 @@ public class StockForecastOrderingGrid : DynamicItemsListGrid<StockOrderingItem>
             case SupplierProductOrderStrategy.LowestOverallPrice:
             case SupplierProductOrderStrategy.LowestUnitPrice:
             case SupplierProductOrderStrategy.LowestOverstock:
-                return Math.Ceiling(requiredQuantity * DimensionsRatio(supplierProduct));
+                return Math.Ceiling(requiredQuantity);
             default:
                 return 0.0;
         }