Distribution of values

I need to distribute On hand qty to each warehouse by priority, having WHS 01 first in priority, and WHS 03 last.
If SUM of On Hand of particular item is greater then or equals total sum of Stock QTY, i need to distribute On Hand SUM to all warehouses, so that SUM of On Hand matches the sum in each whs by priority. In that case the last whs gets the excess qty. And if sum of on hand qty is less than sum of stock qty, distribution goes by the same priority until total qty is depleted.

Example with the result column attached.

Help much appreciated