from datetime import datetime
from django.db import models
from django.utils import timezone
from django.contrib.auth.models import AbstractBaseUser, BaseUserManager, AbstractUser, Group, PermissionsMixin

from specializations.models import Specialization


class UserManager(BaseUserManager):
    def create_user(self, email, password=None):
        if not email:
            raise ValueError('Users must have an email address')
        
        user = self.model(email=UserManager.normalize_email(email),)
        user.set_password(password)
        user.save(using=self._db)
        return user
    
    def create_superuser(self, email, password):
        user = self.create_user(email, password)
        user.is_superuser = True
        user.save(using=self._db)
        return user


class ContractorUserManager(models.Manager):
    def get_queryset(self):
        return super().get_queryset().filter(groups__name='Исполнители')


class CustomerUserManager(models.Manager):
    def get_queryset(self):
        return super().get_queryset().filter(groups__name='Заказчики')


class User(AbstractBaseUser, PermissionsMixin):
    STATUSES = (
        ('free', 'Свободен'),
        ('busy', 'Занят'),
    )
    nickname = models.CharField(max_length=50, blank=True,null=True)
    first_name = models.CharField(max_length=255, blank=True)
    last_name = models.CharField(max_length=255, blank=True)
    email = models.EmailField(max_length=255, unique=True, db_index=True)
    is_active = models.BooleanField(default=True)
    created = models.DateTimeField(default=timezone.now)
    last_time_visit = models.DateTimeField(default=timezone.now)
    contractor_specializations = models.ManyToManyField(Specialization, related_name='contractors', blank=True)
    contractor_status = models.CharField(default='free', max_length=20, choices=STATUSES)
    
    @property
    def is_staff(self):
        return self.is_superuser

    @property
    def is_free(self):
        return self.contractor_status == 'free'

    
    def __str__(self):
        return self.email
    
    def get_short_name(self):
        return self.email
    
    def get_full_name(self):
        return self.first_name + ' ' + self.last_name
    
    USERNAME_FIELD = 'email'
    REQUIRED_FIELDS = []
    objects = UserManager()
    contractor_objects = ContractorUserManager()
    customer_objects = CustomerUserManager()
    
    class Meta:
        verbose_name = 'Пользователь'
        verbose_name_plural = 'Пользователи'

    def is_contractor(self):
        return self.groups.filter(name='Исполнители').exists()

    def is_customer(self):
        return self.groups.filter(name='Заказчики').exists()



class Team(models.Model):
    name = models.CharField(max_length=255)
    users = models.ManyToManyField(User, related_name ='teams', blank=True)
    owner = models.OneToOneField(User, related_name='team', blank=True, null=True)
    # groups = models.ManyToManyField(Group, related_name='teams', blank=True)
    
    def __str__(self):
        return self.name
    
    class Meta:
        verbose_name = 'Команда'
        verbose_name_plural = 'Команды'