From d9c00b129ba7603b47cfab74fe4153d4551dee30 Mon Sep 17 00:00:00 2001
From: "Quentin (OpenERP)" <qdp-launchpad@openerp.com>
Date: Thu, 23 May 2013 14:28:55 +0200
Subject: [PATCH] [FIX] account: divide the residual amount of invoices
 proportionally to the number of invoices partially reconciled together if
 needed + if necessary, do a conversion at the right currency rate

bzr revid: qdp-launchpad@openerp.com-20130523122855-n0o1rz9ajxkbgsnj
---
 addons/account/account_invoice.py | 36 ++++++++++++++++++++++++++++---
 1 file changed, 33 insertions(+), 3 deletions(-)

diff --git a/addons/account/account_invoice.py b/addons/account/account_invoice.py
index 057947205f0..282c1712d19 100644
--- a/addons/account/account_invoice.py
+++ b/addons/account/account_invoice.py
@@ -92,13 +92,43 @@ class account_invoice(osv.osv):
         return [('none', _('Free Reference'))]
 
     def _amount_residual(self, cr, uid, ids, name, args, context=None):
+        """Function of the field residua. It computes the residual amount (balance) for each invoice"""
+        if context is None:
+            context = {}
+        ctx = context.copy()
         result = {}
+        currency_obj = self.pool.get('res.currency')
         for invoice in self.browse(cr, uid, ids, context=context):
+            nb_inv_in_partial_rec = max_invoice_id = 0
             result[invoice.id] = 0.0
             if invoice.move_id:
-                for m in invoice.move_id.line_id:
-                    if m.account_id.type in ('receivable','payable'):
-                        result[invoice.id] += m.amount_residual_currency
+                for aml in invoice.move_id.line_id:
+                    if aml.account_id.type in ('receivable','payable'):
+                        if aml.currency_id and aml.currency_id.id == invoice.currency_id.id:
+                            result[invoice.id] += aml.amount_residual_currency
+                        else:
+                            ctx['date'] = aml.date
+                            result[invoice.id] += currency_obj.compute(cr, uid, aml.company_id.currency_id.id, invoice.currency_id.id, aml.amount_residual, context=ctx)
+
+                        if aml.reconcile_partial_id.line_partial_ids:
+                            #we check if the invoice is partially reconciled and if there are other invoices
+                            #involved in this partial reconciliation (and we sum these invoices)
+                            for line in aml.reconcile_partial_id.line_partial_ids:
+                                if line.invoice:
+                                    nb_inv_in_partial_rec += 1
+                                    #store the max invoice id as for this invoice we will make a balance instead of a simple division
+                                    max_invoice_id = max(max_invoice_id, line.invoice.id)
+            if nb_inv_in_partial_rec:
+                #if there are several invoices in a partial reconciliation, we split the residual by the number
+                #of invoice to have a sum of residual amounts that matches the partner balance
+                new_value = currency_obj.round(cr, uid, invoice.currency_id, result[invoice.id] / nb_inv_in_partial_rec)
+                if invoice.id == max_invoice_id:
+                    #if it's the last the invoice of the bunch of invoices partially reconciled together, we make a
+                    #balance to avoid rounding errors
+                    result[invoice.id] = result[invoice.id] - ((nb_inv_in_partial_rec - 1) * new_value)
+                else:
+                    result[invoice.id] = new_value
+
             #prevent the residual amount on the invoice to be less than 0
             result[invoice.id] = max(result[invoice.id], 0.0)            
         return result