Calculate tax IDs when refunding items

Author: hichamboushaba

WooCommerce/src/main/kotlin/com/woocommerce/android/ui/payments/refunds/IssueRefundViewModel.kt

@@ -539,7 +539,7 @@ class IssueRefundViewModel @Inject constructor(
 
                 // Update the subtotal and taxes based on the new quantity
                 val subtotal = newItem.calculateTotalSubtotal()
-                val taxes = listOf(TaxRefund(0L, newItem.calculateTotalTaxes()))
+                val taxes = newItem.calculateTotalTaxes()
                 newItem = newItem.copy(subtotal = subtotal, taxes = taxes)
 
                 newItems.add(newItem)

WooCommerce/src/main/kotlin/com/woocommerce/android/ui/payments/refunds/RefundsExt.kt

@@ -1,5 +1,6 @@
 package com.woocommerce.android.ui.payments.refunds
 
+import org.wordpress.android.fluxc.utils.sumBy
 import java.math.BigDecimal
 import java.math.RoundingMode.HALF_UP
 
@@ -8,7 +9,7 @@ fun List<ProductRefundListItem>.calculateTotals(): Pair<BigDecimal, BigDecimal>
     var subtotal = BigDecimal.ZERO
     this.forEach { item ->
         subtotal += item.calculateTotalSubtotal()
-        taxes += item.calculateTotalTaxes()
+        taxes += item.calculateTotalTaxes().sumBy { it.tax }
     }
     return Pair(subtotal, taxes)
 }
@@ -18,9 +19,12 @@ fun ProductRefundListItem.calculateTotalSubtotal(): BigDecimal {
     return quantity.times(orderItem.price)
 }
 
-fun ProductRefundListItem.calculateTotalTaxes(): BigDecimal {
+fun ProductRefundListItem.calculateTotalTaxes(): List<TaxRefund> {
     val quantity = quantity.toBigDecimal()
+    val taxes = orderItem.taxes
 
-    val singleItemTax = orderItem.totalTax.divide(orderItem.quantity.toBigDecimal(), 2, HALF_UP)
-    return quantity.times(singleItemTax)
+    return taxes.map {
+        val tax = it.taxAmount.divide(orderItem.quantity.toBigDecimal(), 2, HALF_UP)
+        TaxRefund(it.rateId, quantity.times(tax))
+    }
 }