add check method for ean8, ean13 and upc

product_gtin/product_gtin.py

@@ -37,6 +37,53 @@ def check_ean(eancode):
         int(eancode)
     except:
         return False
+    check = True
+    if len(eancode) == 8:
+        check = check_ean8(eancode)
+    if len(eancode) == 11:
+        check = check_ean11(eancode)
+    if len(eancode) == 12:
+        check = check_upc(eancode)
+    if len(eancode) == 13:
+        check = check_ean13(eancode)
+    if len(eancode) == 14:
+        check = check_gtin14(eancode)
+    return check
+
+
+def check_ean8(eancode):
+    sum = 0
+    ean_len = int(len(eancode))
+    for i in range(ean_len-1):
+        if is_pair(i):
+            sum += 3 * int(eancode[i])
+        else:
+            sum += int(eancode[i])
+    check = 10 - operator.mod(sum, 10)
+    if check == 10:
+        check = 0
+    if check != int(eancode[-1]):
+        return False
+    return True
+
+
+def check_upc(eancode):
+    sum_pair = 0
+    ean_len = int(len(eancode))
+    for i in range(ean_len-1):
+        if is_pair(i):
+            sum_pair += int(eancode[i])
+    sum = sum_pair * 3
+    for i in range(ean_len-1):
+        if not is_pair(i):
+            sum += int(eancode[i])
+    check = ((sum/10 + 1) * 10) - sum
+    if check != int(eancode[-1]):
+        return False
+    return True
+
+
+def check_ean13(eancode):
     sum = 0
     ean_len = int(len(eancode))
     for i in range(ean_len-1):
@@ -53,6 +100,14 @@ def check_ean(eancode):
     return True
 
 
+def check_ean11(eancode):
+    pass
+
+
+def check_gtin14(eancode):
+    pass
+
+
 class product_product(orm.Model):
     _inherit = "product.product"
 
@@ -64,12 +119,12 @@ def _check_ean_key(self, cr, uid, ids):
 
     _columns = {
         'ean13': fields.char(
-            'EAN', size=14,
+            'EAN/GTIN', size=14,
             help="Code for EAN8 EAN13 UPC JPC GTIN "
             "http://en.wikipedia.org/wiki/Global_Trade_Item_Number"),
     }
 
-    _constraints = [(_check_ean_key, 'Error: Invalid EAN code', ['ean13'])]
+    _constraints = [(_check_ean_key, 'Error: Invalid EAN/GTIN code', ['ean13'])]
 
 
 class product_packaging(orm.Model):