from formencode import Schema, validators as v
from pprint import pprint
import hashlib



MD5Password = v.Wrapper(
    not_empty=True,
    to_python=lambda d: hashlib.md5(d).hexdigest()
)

RolesList = v.Wrapper(
    to_python=lambda d: [s.strip() for s in d.split(',')]
)


class RequiredString(v.UnicodeString):
    not_empty = True


class MapFields(v.FormValidator):
    _fields_mapping = {
        'userNameFirst': 'name',
        'userNameSecond': 'second_name',
        'userPassword': 'password',
        'userEmail': 'email',
        'userTitle': 'title',
        'userRoles':'roles'
    }

    def _to_python(self, fields, state):
    	result = {}
    	for key, value in self._fields_mapping.iteritems():
            result[value] = fields[key]
    	return result


class Converter(Schema):
    # FormEncode's Declarative API attributes
    allow_extra_fields = True
    filter_extra_fields = True

    # Our own attributes and fields
    userNameFirst = RequiredString
    userNameSecond = RequiredString
    userPassword = MD5Password
    userEmail = v.Email
    userTitle = v.UnicodeString(if_missing='Bachelor')
    userRoles = RolesList

    chained_validators = [MapFields]



# Test the module
if __name__ == '__main__':
    sample_data = {
        'userNameFirst': 'Adam',
        'userNameSecond': 'Smith',
        'userPassword': 'supersecretpassword',
        'userEmail': 'adam@smith.math.edu',
        'userRoles': 'teacher, worker, admin',
    }

    desired_data = {
        'name': 'Adam',
        'second_name': 'Smith',
        'password': hashlib.md5('supersecretpassword').hexdigest(),
        'email': 'adam@smith.math.edu',
        'title': 'Bachelor',
        'roles': ['teacher', 'worker', 'admin'],
    }
    data = Converter.to_python(sample_data)
    assert data == desired_data
    pprint(data)