[IMP] l10n_in_sale: Simplify GST sale order

GST Treatment:
       * Is show that how This sale order is treated in GST
       * Set default value in customer
       * This is help in GST retrun filing.
       * Value of treamtmnet as below
            - Registered Business - Regular
            - Registered Business - Composition
            - Unregistered Business
            - Consumer
            - Overseas
            - Special Economic Zone
            - Deemed Export
       * GSTIN is required in
            - Registered Business - Regular
            - Registered Business - Composition
            - Special Economic Zone
            - Deemed Export

    Shipping GSTIN:
       * GST identification number or GST number
       * There can be multiple GSTIN for a single person, being an assessee under the Income Tax Act for every State or Union Territory in which such person operates from
       * So When specific invoice and delivery addresses is enabled then user can enter able to enter "Shipping GSTIN" on shipping address of partner
       * Add Validate of this number using regular expression

addons/l10n_in_sale/__manifest__.py

@@ -12,7 +12,8 @@
     ],
     'data': [
         'views/report_sale_order.xml',
-        'views/sale_views.xml'
+        'views/sale_views.xml',
+        'views/res_partner_views.xml',
     ],
     'demo': [
         'data/product_demo.xml',

addons/l10n_in_sale/models/__init__.py

@@ -1,4 +1,6 @@
 # -*- coding: utf-8 -*-
 # Part of Odoo. See LICENSE file for full copyright and licensing details.
 
+from . import res_partner
 from . import sale_order
+from . import account_move

addons/l10n_in_sale/models/account_move.py

@@ -0,0 +1,16 @@
+# -*- coding: utf-8 -*-
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from odoo import api, models
+
+
+class AccountMove(models.Model):
+    _inherit = "account.move"
+
+    def _l10n_in_get_shipping_partner(self):
+        shipping_partner = super()._l10n_in_get_shipping_partner()
+        return self.partner_shipping_id or shipping_partner
+
+    @api.model
+    def _l10n_in_get_shipping_partner_gstin(self, shipping_partner):
+        return shipping_partner.l10n_in_shipping_gstin or shipping_partner.vat

addons/l10n_in_sale/models/res_partner.py

@@ -0,0 +1,18 @@
+# -*- coding: utf-8 -*-
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from odoo import api, fields, models, _
+from odoo.exceptions import ValidationError
+
+
+class ResPartner(models.Model):
+    _inherit = 'res.partner'
+
+    l10n_in_shipping_gstin = fields.Char("Shipping GSTIN")
+
+    @api.constrains('l10n_in_shipping_gstin')
+    def _check_l10n_in_shipping_gstin(self):
+        check_vat_in = self.env['res.partner'].check_vat_in
+        wrong_shipping_gstin_partner = self.filtered(lambda p: p.l10n_in_shipping_gstin and not check_vat_in(p.l10n_in_shipping_gstin))
+        if wrong_shipping_gstin_partner:
+            raise ValidationError(_("The shipping GSTIN number [%s] does not seem to be valid") %(",".join(p.l10n_in_shipping_gstin for p in wrong_shipping_gstin_partner)))

addons/l10n_in_sale/models/sale_order.py

@@ -8,20 +8,38 @@ class SaleOrder(models.Model):
     _inherit = "sale.order"
 
     l10n_in_reseller_partner_id = fields.Many2one('res.partner',
-        string='Reseller', domain="[('vat', '!=', False), '|', ('company_id', '=', False), ('company_id', '=', company_id)]", states={'posted': [('readonly', True)]})
-    l10n_in_journal_id = fields.Many2one('account.journal', string="Journal", states={'posted': [('readonly', True)]})
+        string='Reseller', domain="[('vat', '!=', False), '|', ('company_id', '=', False), ('company_id', '=', company_id)]", readonly=True, states={'draft': [('readonly', False)]})
+    l10n_in_journal_id = fields.Many2one('account.journal', string="Journal", readonly=True, states={'draft': [('readonly', False)]})
+    l10n_in_gst_treatment = fields.Selection([
+            ('regular', 'Registered Business - Regular'),
+            ('composition', 'Registered Business - Composition'),
+            ('unregistered', 'Unregistered Business'),
+            ('consumer', 'Consumer'),
+            ('overseas', 'Overseas'),
+            ('special_economic_zone', 'Special Economic Zone'),
+            ('deemed_export', 'Deemed Export'),
+        ], string="GST Treatment", readonly=True, states={'draft': [('readonly', False)]})
+    l10n_in_company_country_code = fields.Char(related='company_id.country_id.code', string="Country code")
 
     def _prepare_invoice(self):
         invoice_vals = super(SaleOrder, self)._prepare_invoice()
-        invoice_vals['l10n_in_reseller_partner_id'] = self.l10n_in_reseller_partner_id.id
-        if self.l10n_in_journal_id:
-            invoice_vals['journal_id'] = self.l10n_in_journal_id.id
+        if self.l10n_in_company_country_code == 'IN':
+            invoice_vals['l10n_in_reseller_partner_id'] = self.l10n_in_reseller_partner_id.id
+            if self.l10n_in_journal_id:
+                invoice_vals['journal_id'] = self.l10n_in_journal_id.id
+            invoice_vals['l10n_in_gst_treatment'] = self.l10n_in_gst_treatment
         return invoice_vals
 
     @api.onchange('company_id')
     def l10n_in_onchange_company_id(self):
-        domain = [('company_id', '=', self.company_id.id), ('type', '=', 'sale')]
+        if self.l10n_in_company_country_code == 'IN':
+            domain = [('company_id', '=', self.company_id.id), ('type', '=', 'sale')]
+            journal = self.env['account.journal'].search(domain, limit=1)
+            if journal:
+                self.l10n_in_journal_id = journal.id
 
-        journal = self.env['account.journal'].search(domain, limit=1)
-        if journal:
-            self.l10n_in_journal_id = journal.id
+    @api.onchange('partner_id')
+    def onchange_partner_id(self):
+        if self.l10n_in_company_country_code == 'IN':
+            self.l10n_in_gst_treatment = self.partner_id.l10n_in_gst_treatment
+        return super().onchange_partner_id()

addons/l10n_in_sale/views/res_partner_views.xml

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<odoo>
+    <record id="l10n_in_view_partner_form" model="ir.ui.view">
+        <field name="name">l10n.in.res.partner.vat.inherit</field>
+        <field name="model">res.partner</field>
+        <field name="priority" eval="100"/>
+        <field name="inherit_id" ref="base.view_partner_form"/>
+        <field name="arch" type="xml">
+            <xpath expr="//field[@name='vat']" position="after">
+                <field name="l10n_in_shipping_gstin" groups="sale.group_delivery_invoice_address" attrs="{'invisible': ['|',('type', '!=', 'delivery'),('parent_id', '=', False)]}"/>
+            </xpath>
+            <xpath expr="//field[@name='child_ids']/form//field[@name='comment']" position="before">
+                <field name="l10n_in_shipping_gstin" groups="sale.group_delivery_invoice_address" attrs="{'invisible': [('type', '!=', 'delivery')]}"/>
+            </xpath>
+        </field>
+    </record>
+</odoo>

addons/l10n_in_sale/views/sale_views.xml

@@ -6,10 +6,14 @@
         <field name="inherit_id" ref="sale.view_order_form"/>
         <field name="arch" type="xml">
             <xpath expr="//field[@name='partner_id']" position="after">
-                <field name="l10n_in_reseller_partner_id" groups="l10n_in.group_l10n_in_reseller"/>
+                <field name="l10n_in_company_country_code" invisible="1"/>
+                <field name="l10n_in_reseller_partner_id" groups="l10n_in.group_l10n_in_reseller"
+                    attrs="{'invisible': [('l10n_in_company_country_code','!=', 'IN')]}"/>
+                <field name="l10n_in_gst_treatment"
+                    attrs="{'invisible':[('l10n_in_company_country_code','!=','IN')],'required':[('l10n_in_company_country_code','=','IN')]}"/>
             </xpath>
             <xpath expr="//group[@name='sale_info']//field[@name='invoice_status']" position="after">
-                <field name="l10n_in_journal_id" domain="[('company_id', '=', company_id), ('type','=','sale')]" options="{'no_create': True}"/>
+                <field name="l10n_in_journal_id" domain="[('company_id', '=', company_id), ('type','=','sale')]" options="{'no_create': True}" attrs="{'invisible': [('l10n_in_company_country_code','!=', 'IN')]}"/>
             </xpath>
         </field>
     </record>