Query model with calculations from two relation tables

I have 3 tables and 3 models for each : Invoice / Payment / Item

invoices : table
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| id | user_id | discount_amount  | due_at
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items : table
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| id | invoice_id | description | price 
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payments : table
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| id | invoice_id | amount | created_at
---------------------------------------------------------

What I want is to query the (Invoice) model using sum of item prices minus the sum of payments and discount amount ( i.e => selected invoices where ( sum(items.price) - sum(payments.amount) - discount_amount ) > some value ).

basically query which invoices are paid, not paid or partially paid

my current query for index look like this :

public function index() {
          $invoices = Invoice::with('items', 'payments', 'user')->where('void', '!=', 1)->get()
}

Many Thanks :)