[IMP] account_payment: add invoice / transaction link

Purpose of this commit is to add a link between invoices and transactions
to store payment data like what is already done for sale orders.

 * add payment_tx_id on account.invoice model that stores the last
   transaction; also add the acquirer related on the tx;
 * add a stat button on invoice with links to all transactions linked
   to that invoice;
 * add account_invoice_id on payment.transaction model that stores the
   link to the invoice;
 * add the inverse one2many from invoice to all its transactions so
   that we can browse them if necessary;

addons/account_payment/__init__.py

@@ -1,2 +1,4 @@
 # -*- coding: utf-8 -*-
 # Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from . import models

addons/account_payment/__manifest__.py

@@ -14,6 +14,8 @@ enable payment.
 """,
     'depends': ['payment', 'account'],
     'data': [
+        'views/account_invoice_views.xml',
+        'views/payment_views.xml',
         'views/account_portal_templates.xml',
     ],
     'installable': True,

addons/account_payment/models/__init__.py

@@ -0,0 +1,5 @@
+# -*- coding: utf-8 -*-
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from . import account_invoice
+from . import payment

addons/account_payment/models/account_invoice.py

@@ -0,0 +1,40 @@
+# -*- coding: utf-8 -*-
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from odoo import fields, models, _
+
+
+class AccountInvoice(models.Model):
+    _inherit = 'account.invoice'
+
+    payment_tx_ids = fields.One2many('payment.transaction', 'account_invoice_id', string='Transactions')
+    payment_tx_id = fields.Many2one('payment.transaction', string='Last Transaction', copy=False)
+    payment_acquirer_id = fields.Many2one(
+        'payment.acquirer', string='Payment Acquirer',
+        related='payment_tx_id.acquirer_id', store=True)
+    payment_tx_count = fields.Integer(string="Number of payment transactions", compute='_compute_payment_tx_count')
+
+    def _compute_payment_tx_count(self):
+        tx_data = self.env['payment.transaction'].read_group(
+            [('account_invoice_id', 'in', self.ids)],
+            ['account_invoice_id'], ['account_invoice_id']
+        )
+        mapped_data = dict([(m['account_invoice_id'][0], m['account_invoice_id_count']) for m in tx_data])
+        for invoice in self:
+            invoice.payment_tx_count = mapped_data.get(invoice.id, 0)
+
+    def action_view_transactions(self):
+        action = {
+            'name': _('Payment Transactions'),
+            'type': 'ir.actions.act_window',
+            'res_model': 'payment.transaction',
+            'target': 'current',
+        }
+        tx = self.env['payment.transaction'].search([('account_invoice_id', 'in', self.ids)])
+        if len(tx) == 1:
+            action['res_id'] = tx.ids[0]
+            action['view_mode'] = 'form'
+        else:
+            action['view_mode'] = 'tree,form'
+            action['domain'] = [('account_invoice_id', 'in', self.ids)]
+        return action

addons/account_payment/models/payment.py

@@ -0,0 +1,10 @@
+# -*- coding: utf-8 -*-
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from odoo import fields, models
+
+
+class PaymentTransaction(models.Model):
+    _inherit = 'payment.transaction'
+
+    account_invoice_id = fields.Many2one('account.invoice', string='Invoice')

addons/account_payment/views/account_invoice_views.xml

@@ -0,0 +1,17 @@
+<?xml version="1.0"?>
+<odoo>
+    <record id="account_invoice_view_form_inherit_payment" model="ir.ui.view">
+            <field name="name">account.invoice.view.form.inherit.payment</field>
+            <field name="model">account.invoice</field>
+            <field name="inherit_id" ref="account.invoice_form"/>
+            <field name="arch" type="xml">
+	            <xpath expr="//div[@name='button_box']" position="inside">
+	                <button name="action_view_transactions" type="object"
+	                		class="oe_stat_button" icon="fa-money"
+	                		attrs="{'invisible': [('payment_tx_count', '=', 0)]}">
+	                    <field name="payment_tx_count" widget="statinfo" string="Transactions"/>
+	                </button>
+	            </xpath>
+            </field>
+    </record>
+</odoo>

addons/account_payment/views/payment_views.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0"?>
+<odoo>
+    <record id="payment_transaction_view_form" model="ir.ui.view">
+            <field name="name">payment.transaction.view.form.inherit.account.payment</field>
+            <field name="model">payment.transaction</field>
+            <field name="inherit_id" ref="payment.transaction_form"/>
+            <field name="arch" type="xml">
+	            <xpath expr="//field[@name='acquirer_reference']" position="after">
+	            	<field name="account_invoice_id"/>
+	            </xpath>
+            </field>
+    </record>
+</odoo>