Update the way that tax and total amount are calculated trying to control all the possibles combinations

account.py

@@ -25,6 +25,8 @@ class TemplateTax:
         'Intracommunity Key')
     sii_subjected_key = fields.Selection(IVA_SUBJECTED, 'Subjected Key')
     sii_excemption_key = fields.Selection(EXCEMPTION_CAUSE, 'Excemption Key')
+    tax_used = fields.Boolean('Used in Tax')
+    invoice_used = fields.Boolean('Used in invoice Total')
 
     def _get_tax_value(self, tax=None):
         res = super(TemplateTax, self)._get_tax_value(tax)
@@ -50,3 +52,5 @@ class Tax:
         'Intracommunity Key')
     sii_subjected_key = fields.Selection(IVA_SUBJECTED, 'Subjected Key')
     sii_excemption_key = fields.Selection(EXCEMPTION_CAUSE, 'Excemption Key')
+    tax_used = fields.Boolean('Used in Tax')
+    invoice_used = fields.Boolean('Used in invoice Total')

aeat_mapping.py

@@ -20,23 +20,7 @@ __all__ = [
 _logger = getLogger(__name__)
 
 
-# Only for 3.4 and 3.8 version
-def _amount_getter(field_name):
-    def amount_getter(self, field):
-        pool = Pool()
-        InvoiceTax = pool.get('account.invoice.tax')
-        if isinstance(field, InvoiceTax):
-            invoice = field.invoice
-        else:
-            invoice = field
-        val = attrgetter(field_name)(field)
-        credit_note = invoice.type in ('in_credit_note', 'out_credit_note')
-        return val if val is None or not credit_note else -val
-    return amount_getter
-
-
 class BaseTrytonInvoiceMapper(Model):
-
     def __init__(self, *args, **kwargs):
         super(BaseTrytonInvoiceMapper, self).__init__(*args, **kwargs)
         self.pool = Pool()
@@ -51,29 +35,42 @@ class BaseTrytonInvoiceMapper(Model):
     exempt_kind = attrgetter('sii_excemption_key')
     counterpart_nif = attrgetter('party.vat_number')
 
-    def get_untaxed_amount(self, invoice):
-        taxes = self.taxes(invoice)
-        untaxed = 0
-        for tax in taxes:
-            untaxed += _amount_getter('company_base')
-        return untaxed
+    def get_tax_amount(self, tax):
+        invoice = tax.invoice
+        val = attrgetter('company_amount')(tax)
+        credit_note = invoice.type in ('in_credit_note', 'out_credit_note')
+        return val if val is None or not credit_note else -val
 
-    def get_total_amount(self, invoice):
+    def get_tax_base(self, tax):
+        invoice = tax.invoice
+        val = attrgetter('company_base')(tax)
+        credit_note = invoice.type in ('in_credit_note', 'out_credit_note')
+        return val if val is None or not credit_note else -val
+
+    def get_invoice_untaxed(self, invoice):
         taxes = self.taxes(invoice)
-        total = 0
+        taxes_base = 0
         for tax in taxes:
-            tax_base = _amount_getter('company_base')
-            tax_amount = _amount_getter('company_amount')
-            total += (tax_base + tax_amount)
-        return total
+            taxes_base += self.get_tax_base(tax)
+        return taxes_base
+
+    def get_invoice_total(self, invoice):
+        taxes = self.total_invoice_taxes(invoice)
+        taxes_base = 0
+        taxes_amount = 0
+        val = attrgetter('company_total_amount')(invoice)
+        for tax in taxes:
+            taxes_base += self.get_tax_base(tax)
+            taxes_amount += self.get_tax_amount(tax)
+        return (taxes_amount + taxes_base)
 
     counterpart_id_type = attrgetter('party.sii_identifier_type')
     counterpart_id = counterpart_nif
-    untaxed_amount = get_untaxed_amount
-    total_amount = get_total_amount
+    untaxed_amount = get_invoice_untaxed
+    total_amount = get_invoice_total
     tax_rate = attrgetter('tax.rate')
-    tax_base = _amount_getter('company_base')
-    tax_amount = _amount_getter('company_amount')
+    tax_base = get_tax_base
+    tax_amount = get_tax_amount
 
     def counterpart_name(self, invoice):
         return tools.unaccent(invoice.party.name)
@@ -107,7 +104,16 @@ class BaseTrytonInvoiceMapper(Model):
         return [
             invoice_tax for invoice_tax in invoice.taxes
             if (
-                invoice_tax.tax.sii_subjected_key == 'S1' and
+                invoice_tax.tax.tax_used and
+                not invoice_tax.tax.recargo_equivalencia
+            )
+        ]
+
+    def total_invoice_taxes(self, invoice):
+        return [
+            invoice_tax for invoice_tax in invoice.taxes
+            if (
+                invoice_tax.tax.invoice_used and
                 not invoice_tax.tax.recargo_equivalencia
             )
         ]

view/tax_form.xml

@@ -4,6 +4,10 @@ contains the full copyright notices and license terms. -->
 <data>
     <xpath expr="/form/notebook/page[@id=&quot;code&quot;]" position="after">
         <page string="AEAT SII" id="aeatsii">
+            <label name="tax_used"/>
+            <field name="tax_used"/>
+            <label name="invoice_used"/>
+            <field name="invoice_used"/>
             <label name="sii_book_key"/>
             <field name="sii_book_key"/>
             <label name="sii_issued_key"/>