from django.conf import settings

from django.contrib.auth import models as auth_models

from django.contrib.auth.models import (UserManager, Group,

    BaseUserManager, Permission, AbstractBaseUser, PermissionsMixin)

from django.contrib.contenttypes.models import ContentType

from django.core import validators

from django.core.mail import send_mail

from django.db import models

from django.db.models.signals import post_migrate

from django.db.models.signals import post_save

from django.utils import timezone

from django.utils.translation import ugettext_lazy as _

from sorl.thumbnail import ImageField

from ldt.user import MAX_USERNAME_LENGTH, MAX_FIRST_NAME_LENGTH, MAX_LAST_NAME_LENGTH

class LdtUserManager(BaseUserManager):

    def create_user(self, username, email=None, password=None, **extra_fields):

        """

        Creates and saves a User with the given username, email and password.

        """

        now = timezone.now()

        if not username:

            raise ValueError('The given username must be set')

        email = UserManager.normalize_email(email)

        user = self.model(username=username, email=email,

                          is_staff=False, is_active=True, is_superuser=False,

                          last_login=now, date_joined=now, **extra_fields)

        user.set_password(password)

        user.save(using=self._db)

        everyone, _ = Group.objects.get_or_create(name=settings.PUBLIC_GROUP_NAME)

        user.groups.add(everyone)

        return user

    def create_superuser(self, username, email, password, **extra_fields):

        u = self.create_user(username, email, password, **extra_fields)

        u.is_staff = True

        u.is_active = True

        u.is_superuser = True

        u.save(using=self._db)

        return u

# This method was added to stabilize migrations

def get_group_image_upload_to(instance, filename):

    return settings.MEDIA_ROOT+"thumbnails/groups/"

def get_group_image_default():

    return settings.DEFAULT_GROUP_ICON

class GroupProfile(models.Model):

    group = models.OneToOneField(Group, primary_key=False, related_name='profile')

    description = models.TextField()

    image = ImageField(upload_to=get_group_image_upload_to, default=get_group_image_default, max_length=200)

    @staticmethod

    def create_group_profile(sender, instance, created, **kwargs):

        if created:

            profile = GroupProfile()

            profile.group_id = instance.id

            profile.save()

            admins = LdtUser.objects.filter(is_superuser=True)

            if admins:

                admin_user = admins[0] 

                admin_user.groups.add(instance)

                admin_user.save()

def get_ldtuser_image_default():

    return settings.DEFAULT_USER_ICON

def get_ldtuser_language_default():

    if hasattr(settings, 'LANGUAGE_CODE'):

        return settings.LANGUAGE_CODE[:2]

    else :

        return 'en'

class LdtUser(AbstractBaseUser, PermissionsMixin):

    """

    An abstract base class implementing a fully featured User model with

    admin-compliant permissions.

    Username and password are required. Other fields are optional.

    """

    username = models.CharField(

        _('username'),

        max_length=MAX_USERNAME_LENGTH,

        unique=True,

        help_text=_('Required. %d characters or fewer. Letters, digits and @/./+/-/_ only.' % MAX_USERNAME_LENGTH),

        validators=[

            validators.RegexValidator(

                r'^[\w.@+-]+$',

                _('Enter a valid username. This value may contain only '

                  'letters, numbers ' 'and @/./+/-/_ characters.')

            ),

        ],

        error_messages={

            'unique': _("A user with that username already exists."),

        },

    )

    first_name = models.CharField(_('first name'), max_length=MAX_FIRST_NAME_LENGTH, blank=True)

    last_name = models.CharField(_('last name'), max_length=MAX_LAST_NAME_LENGTH, blank=True)

    external_id = models.CharField(_('external id'), max_length=MAX_USERNAME_LENGTH, blank=True)

    email = models.EmailField(_('email address'), blank=True)

    is_staff = models.BooleanField(

        _('staff status'),

        default=False,

        help_text=_('Designates whether the user can log into this admin site.'),

    )

    is_active = models.BooleanField(

        _('active'),

        default=True,

        help_text=_(

            'Designates whether this user should be treated as active. '

            'Unselect this instead of deleting accounts.'

        ),

    )

    date_joined = models.DateTimeField(_('date joined'), default=timezone.now)

    language = models.CharField(max_length=2, default=get_ldtuser_language_default)

    image = ImageField(upload_to="thumbnails/users/", default=get_ldtuser_image_default, max_length=200)

    objects = LdtUserManager()

    USERNAME_FIELD = 'username'

    REQUIRED_FIELDS = ['email']

    class Meta:

        verbose_name = _('user')

        verbose_name_plural = _('users')

    def get_full_name(self):

        """

        Returns the first_name plus the last_name, with a space in between.

        """

        full_name = '%s %s' % (self.first_name, self.last_name)

        return full_name.strip()

    def get_short_name(self):

        "Returns the short name for the user."

        return self.first_name

    def email_user(self, subject, message, from_email=None, **kwargs):

        """

        Sends an email to this User.

        """

        send_mail(subject, message, from_email, [self.email], **kwargs)

def get_profile(self):

    return self.profile

Group.add_to_class("get_profile", get_profile)  # @UndefinedVariable

post_save.connect(GroupProfile.create_group_profile, sender=Group)

def add_group_permissions(sender, **kwargs):

    ct = ContentType.objects.get(app_label='auth', model='group')

    Permission.objects.get_or_create(codename='is_owner_group', name='Can add/delete admins to the group',content_type=ct)

post_migrate.connect(add_group_permissions, sender=auth_models)