feat(billing): 2d dual-run reconciliation (Odoo-computed vs NexaCloud-actual)

fusion.billing.reconciliation gains the compute: _compute_reconciliation
(flat + charge overage vs external, status match/delta at a tolerance) and
_reconcile_rows (resolve shadow sub -> flat + charge, upsert one row per
service/partner/period, per-row isolated). The wizard gains a read-only
_read_reconciliation_rows (NexaCloud usage cpu_hours*3600 + invoice-item
subtotals per YYYY-MM) and a "Run Reconciliation" button. 2a amended to
stamp x_fc_nexacloud_plan_id on shadow subs so reconciliation can find the
charge. Read-only on NexaCloud; writes only reconciliation rows (shadow
guarantees intact). 8 new tests, full suite green on odoo-trial.

fusion_centralize_billing/tests/__init__.py

@@ -4,3 +4,4 @@ from . import test_usage
 from . import test_api
 from . import test_webhook
 from . import test_importer
+from . import test_reconciliation

fusion_centralize_billing/tests/test_importer.py

@@ -118,6 +118,11 @@ class TestImporterSubscriptions(TransactionCase):
         self.assertAlmostEqual(line2.price_unit, 200.0)            # price_yearly
         self.assertEqual(sub2.plan_id.billing_period_unit, 'year')
 
+    def test_subscription_records_nexacloud_plan_id(self):
+        self.Wizard._import_rows(_fixture())
+        sub1 = self.env['sale.order'].search([('x_fc_nexacloud_subscription_id', '=', 's-1')])
+        self.assertEqual(sub1.x_fc_nexacloud_plan_id, 'p-1')
+
     def test_subscription_skipped_when_user_or_plan_unresolved(self):
         data = _fixture()
         data['subscriptions'].append(

fusion_centralize_billing/tests/test_reconciliation.py

@@ -0,0 +1,91 @@
+# -*- coding: utf-8 -*-
+# Copyright 2026 Nexa Systems Inc.
+# License OPL-1
+from odoo.tests.common import TransactionCase, tagged
+
+from .test_importer import _fixture
+
+
+@tagged('post_install', '-at_install')
+class TestReconciliationMath(TransactionCase):
+
+    def setUp(self):
+        super().setUp()
+        self.Recon = self.env['fusion.billing.reconciliation'].sudo()
+        self.metric = self.env['fusion.billing.metric'].sudo().create(
+            {'name': 'CPU seconds', 'code': 'cpu_seconds', 'aggregation': 'sum'})
+        self.charge = self.env['fusion.billing.charge'].sudo().create({
+            'name': 'CPU', 'plan_code': 'p-1', 'metric_id': self.metric.id,
+            'included_quota': 18000.0, 'price_per_unit': 0.0075,
+            'unit_batch': 3600.0, 'charge_model': 'standard'})
+
+    def test_match_within_tolerance(self):
+        odoo_amt, delta, status = self.Recon._compute_reconciliation(
+            20.0, self.charge, 10000.0, 20.0, 0.01)   # under quota, no overage
+        self.assertAlmostEqual(odoo_amt, 20.0)
+        self.assertEqual(status, 'match')
+
+    def test_overage_match(self):
+        # flat 20 + 2 core-hours overage (7200s -> $0.015) = 20.015; external 20.02 (cent)
+        odoo_amt, delta, status = self.Recon._compute_reconciliation(
+            20.0, self.charge, 18000.0 + 7200.0, 20.02, 0.01)
+        self.assertEqual(status, 'match')
+
+    def test_delta_flags_mismatch(self):
+        odoo_amt, delta, status = self.Recon._compute_reconciliation(
+            20.0, self.charge, 18000.0, 25.0, 0.01)   # external 25 vs odoo 20
+        self.assertAlmostEqual(delta, -5.0, places=2)
+        self.assertEqual(status, 'delta')
+
+    def test_no_charge_is_flat_only(self):
+        odoo_amt, delta, status = self.Recon._compute_reconciliation(
+            20.0, self.env['fusion.billing.charge'], 999999.0, 20.0, 0.01)
+        self.assertAlmostEqual(odoo_amt, 20.0)
+        self.assertEqual(status, 'match')
+
+
+@tagged('post_install', '-at_install')
+class TestReconcileRows(TransactionCase):
+
+    def setUp(self):
+        super().setUp()
+        self.Wizard = self.env['fusion.billing.import.wizard'].sudo()
+        self.Wizard._import_rows(_fixture())   # shadow subs s-1/s-2 + p-1 charge
+        self.Recon = self.env['fusion.billing.reconciliation'].sudo()
+        self.SaleOrder = self.env['sale.order']
+
+    def _partner_of(self, sub_ext):
+        return self.SaleOrder.search(
+            [('x_fc_nexacloud_subscription_id', '=', sub_ext)]).partner_id
+
+    def test_creates_one_row_per_subscription_with_status(self):
+        summary = self.Recon._reconcile_rows([
+            {'subscription_external_id': 's-1', 'period': '2026-05',
+             'cpu_seconds': 0.0, 'external_amount': 20.0},     # flat 20 == 20 -> match
+            {'subscription_external_id': 's-2', 'period': '2026-05',
+             'cpu_seconds': 0.0, 'external_amount': 250.0},    # flat 200 vs 250 -> delta
+        ])
+        rows = self.Recon.search([('period', '=', '2026-05')])
+        self.assertEqual(len(rows), 2)
+        s1 = rows.filtered(lambda r: r.odoo_amount == 20.0)
+        self.assertEqual(s1.status, 'match')
+        s2 = rows.filtered(lambda r: r.odoo_amount == 200.0)
+        self.assertEqual(s2.status, 'delta')
+        self.assertAlmostEqual(s2.delta, -50.0, places=2)
+        self.assertEqual(summary['match'], 1)
+        self.assertEqual(summary['delta'], 1)
+
+    def test_rerun_upserts(self):
+        row = [{'subscription_external_id': 's-1', 'period': '2026-05',
+                'cpu_seconds': 0.0, 'external_amount': 20.0}]
+        self.Recon._reconcile_rows(row)
+        self.Recon._reconcile_rows(row)
+        self.assertEqual(self.Recon.search_count([
+            ('period', '=', '2026-05'),
+            ('partner_id', '=', self._partner_of('s-1').id)]), 1)
+
+    def test_unknown_subscription_is_skipped(self):
+        summary = self.Recon._reconcile_rows([
+            {'subscription_external_id': 'nope', 'period': '2026-05',
+             'cpu_seconds': 0.0, 'external_amount': 1.0}])
+        self.assertTrue(any(s['id'] == 'nope' for s in summary['skipped']))