class CustomUserManager(BaseUserManager):

    def _create_user(self, username, email, password,
                     is_staff, is_superuser, **extra_fields):
        """
        Creates and saves a User with the given username, email and password.
        """
        if not username:
            raise ValueError('The given username must be set')
        email = self.normalize_email(email)
        user = self.model(username=username, email=email,
                          is_staff=is_staff, is_active=True,
                          is_superuser=is_superuser, **extra_fields)
        user.set_password(password)
        user.save(using=self._db)
        return user

    def create_user(self, username, email=None, password=None,
                    **extra_fields):
        return self._create_user(username, email, password, False, False,
                                 **extra_fields)

    def create_superuser(self, username, email, password, **extra_fields):
        return self._create_user(username, email, password, True, True,
                                 **extra_fields)


def myoverridenmeta(name, bases, adict):
    newClass = type(name, bases, adict)
    for field in newClass._meta.fields:
        if field.attname == 'last_login':
            field.column = 'lastlogin'
            field.db_column = 'lastlogin'
    return newClass


class UserProfile(AbstractBaseUser):

    class Meta:
        """
        meta class for user role, defining ordering and db table name
        """
        ordering = ["name"]
        db_table = 'user'

    username = models.CharField(max_length=254, unique=True)
    name = models.CharField(max_length=254, blank=True)
    email = models.EmailField(blank=True, unique=True)
    createdon = models.DateTimeField(auto_now_add=True)
    updatedon = models.DateTimeField(auto_now=True)
    is_active = models.BooleanField(default=True, db_column='status')
    is_admin = models.BooleanField(default=False, db_column='isadmin')
    is_staff = models.BooleanField(default=False, db_column='isstaff')
    is_superuser = models.BooleanField(default=False, db_column='issuperuser')

    USERNAME_FIELD = 'username'
    REQUIRED_FIELDS = ['email']

    objects = CustomUserManager()

    def get_full_name(self):
        return self.username

    def get_short_name(self):
        return self.username

    __metaclass__ = myoverridenmeta

class UserList(generics.ListCreateAPIView):
    """
    ListAPI view for get list of Users and create User instance
    """
    queryset = UserProfile.objects.all()
    model = UserProfile
    serializer_class = UserSerializer
    paginate_by = 10
    permission_classes = (IsAuthenticated, IsAdminUser,)

    def get_queryset(self):
        """
        Method to get query params and return search results for User
        :return: Search Result
        """
        queryset = UserProfile.objects.all()
        search_query = self.request.query_params.get('user', None)

        if search_query is not None:
            queryset = queryset.filter(username__istartswith=search_query)
        queryset = queryset.order_by('username')
        return queryset


class UserDetail(generics.RetrieveUpdateAPIView):
    """
    Class based API view to Retrieve, Update a User instance
    """
    queryset = UserProfile.objects.all()
    model = UserProfile
    serializer_class = UserSerializer
    permission_classes = (IsAuthenticated, UserIsOwnerOrAdmin,)


class UserDelete(generics.DestroyAPIView):

    queryset = UserProfile.objects.all()
    model = UserProfile
    serializer_class = UserSerializer
    permission_classes = (IsAuthenticated, IsAdminUser,)