[ADD] purchase: add the two-step validation process

Two-step validation process is set up at the level of the company.

addons/purchase/company.py

@@ -1,13 +1,19 @@
 # -*- coding: utf-8 -*-
 # Part of Odoo. See LICENSE file for full copyright and licensing details.
 
-from openerp import api, fields, models, _
+from openerp import fields, models
 
 class company(models.Model):
     _inherit = 'res.company'
-    po_lead = fields.Float(string='Purchase Lead Time', required=True,
-        help="Margin of error for vendor lead times. When the system "\
-             "generates Purchase Orders for procuring products, "\
-             "they will be scheduled that many days earlier "\
+
+    po_lead = fields.Float(string='Purchase Lead Time', required=True,\
+        help="Margin of error for vendor lead times. When the system "
+             "generates Purchase Orders for procuring products, "
+             "they will be scheduled that many days earlier "
              "to cope with unexpected vendor delays.", default=1.0)
 
+    po_double_validation = fields.Selection([
+        ('one_step', 'Confirm purchase orders in one step'),
+        ('two_step', 'Get 2 levels of approvals to confirm a purchase order')
+        ], string="Levels of Approvals", default='one_step',\
+        help="Provide a double validation mechanism for purchases")

addons/purchase/company_view.xml

@@ -10,6 +10,7 @@
             <field name="arch" type="xml">
                 <xpath expr="//group[@name='logistics_grp']" position="inside">
                         <field name="po_lead"/>
+                        <field name="po_double_validation" widget="radio"/>
                 </xpath>
             </field>
         </record>

addons/purchase/purchase.py

@@ -145,6 +145,7 @@ class PurchaseOrder(models.Model):
     product_id = fields.Many2one('product.product', related='order_line.product_id', string='Product')
     create_uid = fields.Many2one('res.users', 'Responsible')
     company_id = fields.Many2one('res.company', 'Company', required=True, select=1, states=READONLY_STATES, default=lambda self: self.env.user.company_id.id)
+    po_double_validation = fields.Selection(related='company_id.po_double_validation', store=False, readonly=True)
 
     picking_type_id = fields.Many2one('stock.picking.type', 'Deliver To', states=READONLY_STATES, required=True, default=_default_picking_type,\
         help="This will determine picking type of incoming shipment")
@@ -242,7 +243,13 @@ class PurchaseOrder(models.Model):
 
     @api.multi
     def button_confirm(self):
-        return self.button_approve()
+        # Deal with double validation process
+        if self.user_has_groups('purchase.group_purchase_manager'):
+            return self.button_approve()
+        elif self.po_double_validation == 'two_step':
+            self.write({'state': 'to approve'})
+        else:
+            return self.button_approve()
 
     @api.multi
     def button_cancel(self):

addons/purchase/purchase_view.xml

@@ -143,14 +143,18 @@
                     <button name="print_quotation" string="Re-Print RFQ" type="object" states="sent" groups="base.group_user"/>
                     <button name="button_confirm" type="object" states="draft" string="Confirm Order" id="draft_confirm"/>
                     <button name="button_confirm" type="object" states="sent" string="Confirm Order" class="oe_highlight" id="bid_confirm"/>
-                    <button name="button_approve" type="object" states="to approve" string="Approve Order" class="oe_highlight" groups="purchase.group_purchase_manager"/>
+                    <button name="button_approve" type="object" string="Approve Order" class="oe_highlight" groups="purchase.group_purchase_manager"
+                        attrs="{'invisible': ['|', ('state', 'not in', ('to approve')), ('po_double_validation', '=', 'one_step')]}"/>
                     <button name="action_rfq_send" states="approved" string="Send PO by Email" type="object" context="{'send_rfq':False}"/>
                     <button name="%(purchase_open_picking)d" string="Receive Products" type="action" attrs="{'invisible': [('state','not in', ('purchase','done'))]}"/>
                     <button name="button_draft" states="cancel" string="Set to Draft" type="object" />
                     <button name="button_cancel" states="draft,to approve,sent,purchase" string="Cancel" type="object" />
                     <button name="button_done" type="object" string="Set to Done" states="purchase"
                         help="If a purchase order is done, you can not modify it manually anymore. But you will still be able to bill or receive."/>
-                    <field name="state" widget="statusbar" statusbar_visible="draft,sent,purchase,done" readonly="1"/>
+                    <field name="state" widget="statusbar" statusbar_visible="draft,sent,purchase,done" readonly="1"
+                        attrs="{'invisible': [('po_double_validation', '=', 'two_step')]}"/>
+                    <field name="state" widget="statusbar" statusbar_visible="draft,sent,to approve,purchase,done" readonly="1"
+                        attrs="{'invisible': [('po_double_validation', '=', 'one_step')]}"/>
                 </header>
                 <sheet>
                     <div class="oe_button_box" name="button_box">
@@ -183,6 +187,7 @@
                             <field name="date_order"/>
                             <field name="origin" attrs="{'invisible': [('origin','=',False)]}"/>
                             <field name="company_id" groups="base.group_multi_company" options="{'no_create': True}"/>
+                            <field name="po_double_validation" invisible='1'/>
                         </group>
                     </group>
                     <notebook>