Tax In Purchase Invoice

I need to make the VAT in purchase invoices as debit, unlike the sale invoices as credit.
In our country, the Tax Authorities make their calculations as the following equation:
(Sales Tax) - (Purchase Tax) = Amount (either we pay them or they pay us, depends on the difference).
I noticed that when creating an asset, the VAT by default becomes Debit, this is what i want to do for the Purchase Tax.
I attached a picture that may help in delivering the idea.