Prepare NCF manager for production on Tryton 8.0

sequence.py

@@ -1,18 +1,10 @@
 # This file is part of ncf_manager module for Tryton.  The COPYRIGHT file at the top level of
 # this repository contains the full copyright notices and license terms.
-from string import Template
-import time
-
-from sql import Literal, For
-
 from trytond.exceptions import UserError
-from trytond.model.exceptions import ValidationError
-from trytond.model import ModelView, ModelSQL, DeactivableMixin, fields, Check
-from trytond.pyson import Eval, And
-from trytond.transaction import Transaction
-from trytond.pool import Pool, PoolMeta
+from trytond.model import fields
+from trytond.pyson import Eval
+from trytond.pool import PoolMeta
 from trytond.i18n import gettext
-from trytond import backend
 
 # Maps sequence_type.name → (prefix, padding)
 _NCF_TYPE_MAP = {
@@ -38,6 +30,7 @@ _NCF_TYPE_MAP = {
     'Exportación Electrónico':               ('E46', 10),
     'Pagos al Exterior Electrónico':         ('E47', 10),
 }
+NCF_PREFIXES = tuple(prefix for prefix, _padding in _NCF_TYPE_MAP.values())
 
 
 class Sequence(metaclass=PoolMeta):
@@ -114,8 +107,33 @@ class Sequence(metaclass=PoolMeta):
 
     @fields.depends('number_next', 'until_number')
     def on_change_with_remaining_qty(self, name=None):
-        if self.until_number and self.number_next:
+        if self.until_number is not None and self.number_next is not None:
             return self.until_number - self.number_next + 1
+
+    @classmethod
+    def validate_fields(cls, records, field_names):
+        super().validate_fields(records, field_names)
+        if field_names & {
+                'prefix', 'padding', 'from_number', 'until_number',
+                'number_next'}:
+            for record in records:
+                record._validate_ncf_range()
+
+    def _validate_ncf_range(self):
+        if self.prefix not in NCF_PREFIXES:
+            return
+        expected_padding = 10 if self.prefix.startswith('E') else 8
+        if self.padding != expected_padding:
+            raise UserError(gettext(
+                'ncf_manager.msg_ncf_invalid_padding',
+                padding=expected_padding))
+        if self.from_number is None or self.until_number is None:
+            return
+        if self.from_number < 1 or self.until_number < self.from_number:
+            raise UserError(gettext('ncf_manager.msg_ncf_invalid_range'))
+        if (self.number_next is not None
+                and self.number_next < self.from_number):
+            raise UserError(gettext('ncf_manager.msg_ncf_next_before_range'))
             
 class SequenceStrict(Sequence):
     "Sequence Strict"