Updated

sale_discount_total/models/account_invoice.py

@@ -9,13 +9,14 @@ class AccountInvoice(models.Model):
     @api.one
     @api.depends('invoice_line.price_subtotal', 'tax_line.amount')
     def _compute_amount(self):
+        disc = 0.0
+        for inv in self:
+            for line in inv.invoice_line:
+               disc += (line.quantity * line.price_unit) * line.discount / 100
         self.amount_untaxed = sum(line.price_subtotal for line in self.invoice_line)
         self.amount_tax = sum(line.amount for line in self.tax_line)
-        if self.discount_type == 'percent':
-            self.amount_discount = ((self.amount_untaxed + self.amount_tax) * self.discount_rate) / 100
-        elif self.discount_type == 'amount':
-            self.amount_discount = self.discount_rate
-        self.amount_total = self.amount_untaxed + self.amount_tax - self.amount_discount
+        self.amount_discount = round(disc)
+        self.amount_total = round(self.amount_untaxed + self.amount_tax)
 
     discount_type = fields.Selection([('percent', 'Percentage'), ('amount', 'Amount')], 'Discount Type', readonly=True,
                                      states={'draft': [('readonly', False)]})
@@ -30,23 +31,38 @@ class AccountInvoice(models.Model):
     amount_total = fields.Float(string='Total', digits=dp.get_precision('Account'),
                                 readonly=True, compute='_compute_amount')
 
+    @api.multi
+    def compute_discount(self, discount):
+        print "^^^^^^^^^^^^^^^^^^^^^compute_discount"
+        for inv in self:
+            val1 = val2 = 0.0
+            disc_amnt = 0.0
+            val2 = sum(line.amount for line in self.tax_line)
+            for line in inv.invoice_line:
+                val1 += (line.quantity * line.price_unit)
+                line.discount = discount
+                disc_amnt += (line.quantity * line.price_unit) * discount / 100
+            total = val1 + val2 - disc_amnt
+            self.amount_discount = round(disc_amnt)
+            self.amount_tax = round(val2)
+            self.amount_total = round(total)
+
     @api.onchange('discount_type', 'discount_rate')
-    def compute_discount(self):
+    def supply_rate(self):
         for inv in self:
             amount = sum(line.price_subtotal for line in self.invoice_line)
             tax = sum(line.amount for line in self.tax_line)
             if inv.discount_type == 'percent':
-                if inv.discount_rate == 100:
-                    disc_amnt = amount + tax
-                else:
-                    disc_amnt = (amount + tax) * inv.discount_rate / 100
-                total = amount + tax - disc_amnt
-                self.amount_discount = disc_amnt
-                self.amount_total = total
+                self.compute_discount(inv.discount_rate)
             else:
-                total = (amount + tax) - inv.discount_rate
-                self.amount_discount = inv.discount_rate
-                self.amount_total = total
+                total = 0.0
+                discount = 0.0
+                for line in inv.invoice_line:
+                    total += (line.quantity * line.price_unit)
+                if inv.discount_rate != 0:
+                    discount = (inv.discount_rate / total) * 100
+                self.compute_discount(discount)
+
 
     @api.model
     def _prepare_refund(self, invoice, date=None, period_id=None, description=None, journal_id=None):
@@ -58,31 +74,3 @@ class AccountInvoice(models.Model):
         })
         return res
 
-
-class invoice_line(osv.Model):
-    _inherit = 'account.invoice.line'
-
-    def move_line_get(self, cr, uid, invoice_id, context=None):
-        res = super(invoice_line, self).move_line_get(cr, uid, invoice_id, context=context)
-        inv = self.pool.get('account.invoice').browse(cr, uid, invoice_id, context=context)
-
-        if inv.type in ('out_invoice', 'out_refund') and inv.discount_type:
-            prop = self.pool.get('ir.property').get(cr, uid, 'property_account_income_categ', 'product.category',
-                                                    context=context)
-            prop_id = prop and prop.id or False
-            account_id = self.pool.get('account.fiscal.position').map_account(cr, uid, inv.fiscal_position or False,
-                                                                              prop_id)
-            sign = -1
-
-            res.append({
-                'name': 'Discount',
-                'price_unit': sign * inv.amount_discount,
-                'quantity': 1,
-                'price': sign * inv.amount_discount,
-                'account_id': account_id,
-                'product_id': False,
-                'uos_id': False,
-                'account_analytic_id': False,
-                'taxes': False,
-            })
-        return res

sale_discount_total/models/sale.py

@@ -6,9 +6,11 @@ import openerp.addons.decimal_precision as dp
 class SaleOrder(osv.Model):
     _inherit = 'sale.order'
 
+
     def _amount_all(self, cr, uid, ids, field_name, arg, context=None):
         cur_obj = self.pool.get('res.currency')
         res = {}
+        print "_amount_all"
         for order in self.browse(cr, uid, ids, context=context):
             res[order.id] = {
                 'amount_untaxed': 0.0,
@@ -16,21 +18,17 @@ class SaleOrder(osv.Model):
                 'amount_tax': 0.0,
                 'amount_total': 0.0,
             }
-            val = val1 = val2 = 0.0
             cur = order.pricelist_id.currency_id
+            val1 = val2 = val3 = 0.0
             for line in order.order_line:
                 val1 += line.price_subtotal
-                val += self._amount_line_tax(cr, uid, line, context=context)
-            if order.discount_type == 'amount':
-                val2 = order.discount_rate
-            elif order.discount_type == 'percent':
-                val2 = ((val1 + val) * order.discount_rate) / 100
-            res[order.id]['amount_tax'] = cur_obj.round(cr, uid, cur, val)
-            res[order.id]['amount_untaxed'] = cur_obj.round(cr, uid, cur, val1)
-            res[order.id]['amount_discount'] = cur_obj.round(cr, uid, cur, val2)
-            res[order.id]['amount_total'] = res[order.id]['amount_untaxed'] + res[order.id]['amount_tax'] - \
-                                            res[order.id]['amount_discount']
-        return res
+                val2 += self._amount_line_tax(cr, uid, line, context=context)
+                val3 += (line.product_uom_qty * line.price_unit) * line.discount / 100
+            total = val1 + val2
+            res[order.id]['amount_untaxed'] = round(cur_obj.round(cr, uid, cur, val1))
+            res[order.id]['amount_tax'] = round(cur_obj.round(cr, uid, cur, val2))
+            res[order.id]['amount_discount'] = round(cur_obj.round(cr, uid, cur, val3))
+            res[order.id]['amount_total'] = round(cur_obj.round(cr, uid, cur, total))
 
     def _get_order(self, cr, uid, ids, context=None):
         result = {}
@@ -60,27 +58,33 @@ class SaleOrder(osv.Model):
         'discount_type': 'percent',
     }
 
-    @api.onchange('discount_type', 'discount_rate')
-    def compute_discount(self):
+    @api.multi
+    def compute_discount(self, discount):
         for order in self:
             val1 = val2 = 0.0
+            disc_amnt = 0.0
             for line in order.order_line:
-                val1 += line.price_subtotal
+                val1 += (line.product_uom_qty * line.price_unit)
+                line.discount = discount
                 val2 += self._amount_line_tax(line)
+                disc_amnt += (line.product_uom_qty * line.price_unit * line.discount)/100
+            total = val1 + val2 - disc_amnt
+            self.currency_id = order.pricelist_id.currency_id
+            self.amount_discount = round(disc_amnt)
+            self.amount_tax = round(val2)
+            self.amount_total = round(total)
+
+    @api.onchange('discount_type', 'discount_rate')
+    def supply_rate(self):
+        for order in self:
             if order.discount_type == 'percent':
-                if order.discount_rate == 100:
-                    disc_amnt = val1 + val2
-                else:
-                    disc_amnt = (val1 + val2) * order.discount_rate / 100
-                total = val1 + val2 - disc_amnt
-                self.currency_id = order.pricelist_id.currency_id
-                self.amount_discount = disc_amnt
-                self.amount_total = total
+                self.compute_discount(order.discount_rate)
             else:
-                total = (val1 + val2) - order.discount_rate
-                self.currency_id = order.pricelist_id.currency_id
-                self.amount_discount = order.discount_rate
-                self.amount_total = total
+                total = 0.0
+                for line in order.order_line:
+                    total += (line.product_uom_qty * line.price_unit)
+                discount = (order.discount_rate / total) * 100
+                self.compute_discount(discount)
 
     def _prepare_invoice(self, cr, uid, order, lines, context=None):
         invoice_vals = super(SaleOrder, self)._prepare_invoice(cr, uid, order, lines, context=context)

sale_discount_total/views/account_invoice_view.xml

@@ -14,14 +14,14 @@
                         </group>
                         <group class="oe_subtotal_footer oe_right">
                             <field name="amount_untaxed" widget="monetary" options="{'currency_field': 'currency_id'}"/>
-                                <div>
-                                    <label for="amount_tax"/>
-                                    <button name="button_reset_taxes" states="draft,proforma2"
+                            <field name="amount_discount" widget='monetary' options="{'currency_field': 'currency_id'}"/>
+                            <div>
+                                <label for="amount_tax"/>
+                                <button name="button_reset_taxes" states="draft,proforma2"
                                         string="(update)" class="oe_link oe_edit_only"
                                         type="object" help="Recompute taxes and total"/>
-                                </div>
+                            </div>
                             <field name="amount_tax" nolabel="1" widget="monetary" options="{'currency_field': 'currency_id'}"/>
-                            <field name="amount_discount" widget='monetary' options="{'currency_field': 'currency_id'}"/>
                             <field name="amount_total" class="oe_subtotal_footer_separator" widget="monetary" options="{'currency_field': 'currency_id'}"/>
                             <field name="residual" groups="account.group_account_user" widget="monetary" options="{'currency_field': 'currency_id'}"/>
                             <field name="reconciled" invisible="1"/>

sale_discount_total/views/sale_view.xml

@@ -14,8 +14,8 @@
                         </group>
                         <group class="oe_subtotal_footer oe_right" colspan="2" name="sale_total">
                             <field name="amount_untaxed" widget='monetary' options="{'currency_field': 'currency_id'}"/>
-                            <field name="amount_tax" widget='monetary' options="{'currency_field': 'currency_id'}"/>
                             <field name="amount_discount" widget='monetary' options="{'currency_field': 'currency_id'}"/>
+                            <field name="amount_tax" widget='monetary' options="{'currency_field': 'currency_id'}"/>
                             <div class="oe_subtotal_footer_separator oe_inline">
                                 <label for="amount_total" />
                                 <button name="button_dummy"