*added an integrity check of the iban account number

*added an automatic formatting of the iban account number in order to comply with schema
*added a function the compute the account bank number from the iban account number accordingly to the country rule
*added comments 
*overall improvements

bzr revid: qdp@tinyerp.com-20081001140003-pgvbxcr52jpwxnj6

addons/base_iban/base_iban.py

@@ -31,11 +31,52 @@
 import netsvc
 from osv import fields, osv
 
+def _format_iban(string):
+    '''
+    This function removes all characters from given 'string' that isn't a alpha numeric and converts it to lower case.
+    '''
+    res = ""
+    for char in string:
+        if char.isalnum():
+            res += char.lower()
+    return res
+
 class res_partner_bank(osv.osv):
     _inherit = "res.partner.bank"
-    _columns = {
-        'iban': fields.char('IBAN', size=34, readonly=True, help="International Bank Account Number"),
-    }
+
+    def create(self, cr, uid, vals, context={}):
+        #overwrite to format the iban number correctly
+        if vals.has_key('iban'):
+            vals['iban'] = _format_iban(vals['iban'])
+        return super(res_partner_bank, self).create(cr, uid, vals, context)
+
+    def write(self, cr, uid, ids, vals, context={}):
+        #overwrite to format the iban number correctly
+        if vals.has_key('iban'):
+            vals['iban'] = _format_iban(vals['iban'])
+        return super(res_partner_bank, self).write(cr, uid, ids, vals, context)
+
+    def check_iban(self, cr, uid, ids):
+        '''
+        Check the IBAN number
+        '''
+        for bank_acc in self.browse(cr, uid, ids):
+            if not bank_acc.iban:
+                continue
+            iban =_format_iban(bank_acc.iban) 
+            #the four first digits have to be shifted to the end
+            iban = iban[4:] + iban[:4]
+            #letters have to be transformed into numbers (a = 10, b = 11, ...)
+            iban2 = ""
+            for char in iban:
+                if char.isalpha():
+                    iban2 += str(ord(char)-87)
+                else:
+                    iban2 += char
+            #iban is correct if modulo 97 == 1
+            if not int(iban2) % 97 == 1:
+                return False
+        return True
 
     def name_get(self, cr, uid, ids, context=None):
         res = []
@@ -48,18 +89,50 @@ class res_partner_bank(osv.osv):
         res += super(res_partner_bank, self).name_get(cr, uid, to_check_ids, context)
         return res
 
-    def search(self, cr, uid, args, offset=0, limit=None, order=None,
-            context=None, count=False):
-        res = super(res_partner_bank,self).search(cr, uid, args, offset, limit,
-                order, context=context, count=count)
+    def search(self, cr, uid, args, offset=0, limit=None, order=None, context=None, count=False):
+    #overwrite the search method in order to search not only on bank type == basic account number but also on type == iban
+        res = super(res_partner_bank,self).search(cr, uid, args, offset, limit, order, context=context, count=count)
         if filter(lambda x:x[0]=='acc_number' ,args):
+            #get the value of the search
             iban_value = filter(lambda x:x[0]=='acc_number' ,args)[0][2]
+            #get the other arguments of the search
             args1 =  filter(lambda x:x[0]!='acc_number' ,args)
+            #add the new criterion
             args1 += [('iban','ilike',iban_value)]
+            #append the results to the older search
             res += super(res_partner_bank,self).search(cr, uid, args1, offset, limit,
                 order, context=context, count=count)
         return res
 
+    def get_bban_from_iban(self, cr, uid, ids, context=None):
+        '''
+        This function returns the bank account number computed from the iban account number, thanks to the mapping_list dictionary that contains the rules associated to its country.
+        '''
+        res = {}
+        mapping_list = {
+         #TODO add rules for others countries
+            'be': lambda x: x[4:],
+            'fr': lambda x: x[14:],
+            'ch': lambda x: x[9:],
+            'gb': lambda x: x[14:],
+        }
+        for record in self.browse(cr, uid, ids, context):
+            if not record.iban:
+                res[record.id] = False
+                continue
+            res[record.id] = False
+            for code, function in mapping_list.items():
+                if record.iban.lower().startswith(code):
+                    res[record.id] = function(record.iban)
+                    break
+        return res
+
+    _columns = {
+        'iban': fields.char('IBAN', size=34, readonly=True, help="International Bank Account Number"),
+    }
+
+    _constraints = [(check_iban, "The IBAN number doesn't seem to be correct.", ["iban"])]
+
 res_partner_bank()