from django.contrib.auth.models import AbstractUser, AbstractBaseUser, PermissionsMixin, BaseUserManager
from app.settings import WEBSITE_URI, WEB_APP_NAME
from django.template.loader import render_to_string
from django.core.mail import send_mail
from django.core.urlresolvers import reverse
from django.db import models

# Create your models here.


class UserManager(BaseUserManager):
    def create_user(self, email, first_name, last_name, password=None):
        """
        Creates and saves a User with the given email, first name,
        last name and password.
        """
        if not email:
            raise ValueError('Users must have an email address')

        user = self.model(
            email=self.normalize_email(email),
            first_name=first_name,
            last_name=last_name,
        )

        user.set_password(password)
        user.save(using=self._db)
        return user

    def create_superuser(self, email, first_name, last_name, password):
        """
        Creates and saves a superuser with the given email, first name,
        last name and password.
        """
        user = self.create_user(
            email=email,
            first_name=first_name,
            last_name=last_name,
            password=password,
        )
        user.is_superuser = True
        user.save(using=self._db)
        return user


class User(PermissionsMixin, AbstractBaseUser):
    id = models.AutoField(primary_key=True)
    email = models.EmailField(max_length=256, unique=True)
    first_name = models.CharField(max_length=256)
    last_name = models.CharField(max_length=256)
    is_active = models.BooleanField(default=True)
    is_superuser = models.BooleanField(default=False)

    USERNAME_FIELD = 'email'
    EMAIL_FIELD = 'email'
    REQUIRED_FIELDS = ['first_name', 'last_name']

    objects = UserManager()

    def get_full_name(self):
        return "{} {}".format(self.first_name, self.last_name)

    def get_short_name(self):
        return self.first_name

    def get_absolute_url(self):
        return reverse('driver_details', kwargs={'pk': self.pk})

    def __str__(self):
        # return self.email
        # Show the Identity associated with the user, not the user itself
        try:
            return "{} ({} {})".format(self.identity, self.first_name, self.last_name)
        except:
            return "{} {} ({})".format(self.first_name, self.last_name, self.email)

    def email_user(self, subject, message, from_email=None, **kwargs):
        """Send an email to this user."""
        send_mail(subject, message, from_email, [self.email], **kwargs)

    def send_invite(self, name, to, from_email=None, **kwargs):
        """Send an invite for a new user to register"""
        current_site = WEBSITE_URI
        message = render_to_string('dispatch/invite_email.txt',
                { 'name': name, 'user': self, 'site': current_site,
                    'app_name': WEB_APP_NAME })

        send_mail("Invitation to register at {}".format(current_site),
                    message,
                    from_email,
                    [to])


    @property
    def is_staff(self):
        return self.is_superuser