From 617ef49959d027fab52e2be74aa4c0dc3ce60e30 Mon Sep 17 00:00:00 2001
From: "Pedro M. Baeza" <pedro.baeza@gmail.com>
Date: Thu, 31 Jul 2014 09:07:01 +0200
Subject: [PATCH] [IMP] purchase: Hook for the base price of a purchase line

To be able to change the logic without copying large chunk of code
Closes #1468
---
 addons/purchase/purchase.py | 35 ++++++++++++++++++++++++++++++++---
 1 file changed, 32 insertions(+), 3 deletions(-)

diff --git a/addons/purchase/purchase.py b/addons/purchase/purchase.py
index 3841bec12eb..c5f985f8b82 100644
--- a/addons/purchase/purchase.py
+++ b/addons/purchase/purchase.py
@@ -37,6 +37,7 @@ class purchase_order(osv.osv):
     def _amount_all(self, cr, uid, ids, field_name, arg, context=None):
         res = {}
         cur_obj=self.pool.get('res.currency')
+        line_obj = self.pool['purchase.order.line']
         for order in self.browse(cr, uid, ids, context=context):
             res[order.id] = {
                 'amount_untaxed': 0.0,
@@ -46,8 +47,14 @@ class purchase_order(osv.osv):
             val = val1 = 0.0
             cur = order.pricelist_id.currency_id
             for line in order.order_line:
-               val1 += line.price_subtotal
-               for c in self.pool.get('account.tax').compute_all(cr, uid, line.taxes_id, line.price_unit, line.product_qty, line.product_id, order.partner_id)['taxes']:
+                val1 += line.price_subtotal
+                line_price = line_obj._calc_line_base_price(cr, uid, line,
+                                                            context=context)
+                line_qty = line_obj._calc_line_quantity(cr, uid, line,
+                                                        context=context)
+                for c in self.pool['account.tax'].compute_all(
+                        cr, uid, line.taxes_id, line_price, line_qty,
+                        line.product_id, order.partner_id)['taxes']:
                     val += c.get('amount', 0.0)
             res[order.id]['amount_tax']=cur_obj.round(cr, uid, cur, val)
             res[order.id]['amount_untaxed']=cur_obj.round(cr, uid, cur, val1)
@@ -1020,12 +1027,34 @@ class purchase_order(osv.osv):
 
 
 class purchase_order_line(osv.osv):
+    def _calc_line_base_price(self, cr, uid, line, context=None):
+        """Return the base price of the line to be used for tax calculation.
+
+        This function can be extended by other modules to modify this base
+        price (adding a discount, for example).
+        """
+        return line.price_unit
+
+    def _calc_line_quantity(self, cr, uid, line, context=None):
+        """Return the base quantity of the line to be used for the subtotal.
+
+        This function can be extended by other modules to modify this base
+        quantity (adding for example offers 3x2 and so on).
+        """
+        return line.product_qty
+
     def _amount_line(self, cr, uid, ids, prop, arg, context=None):
         res = {}
         cur_obj=self.pool.get('res.currency')
         tax_obj = self.pool.get('account.tax')
         for line in self.browse(cr, uid, ids, context=context):
-            taxes = tax_obj.compute_all(cr, uid, line.taxes_id, line.price_unit, line.product_qty, line.product_id, line.order_id.partner_id)
+            line_price = self._calc_line_base_price(cr, uid, line,
+                                                    context=context)
+            line_qty = self._calc_line_quantity(cr, uid, line,
+                                                context=context)
+            taxes = tax_obj.compute_all(cr, uid, line.taxes_id, line_price,
+                                        line_qty, line.product_id,
+                                        line.order_id.partner_id)
             cur = line.order_id.pricelist_id.currency_id
             res[line.id] = cur_obj.round(cr, uid, cur, taxes['total'])
         return res