from django.contrib.auth.models import AbstractUser
from django.core.exceptions import ValidationError
from django.db import models
from .managers import CustomUserManager

class CustomUser(AbstractUser):
    # Email koristimo za login, pa mora biti jedinstven
    username=None
    email = models.EmailField(unique=True)

    # ERP Specifična polja
    is_serviser = models.BooleanField(default=False) # Razlikovanje uloga
    is_kupac = models.BooleanField(default=False, verbose_name="Kupac")
    is_team_member = models.BooleanField(default=False, verbose_name="Član tima")

    # Dodatne informacije o servisera
    telefon = models.CharField(max_length=20, blank=True)
    oib = models.CharField(max_length=11, blank=True, null=True)
    occupation = models.CharField(max_length=120, blank=True, default='', verbose_name="Zanimanje")
    residence = models.CharField(max_length=255, blank=True, default='', verbose_name="Prebivalište")
    work_position = models.CharField(max_length=120, blank=True, default='', verbose_name="Na radnom mjestu")
    licence_number = models.CharField(max_length=50, blank=True, null=True, verbose_name="Broj licence")
    is_verified = models.BooleanField(default=False, verbose_name="Verificiran profil")

    # Poveznica na klijenta (ako je korisnik kupac)
    client_profile = models.ForeignKey(
        'crm.Client',
        on_delete=models.SET_NULL,
        null=True,
        blank=True,
        related_name='users',      # Omogućuje pristup: klijent.users.all()
        verbose_name="Povezani klijent"
    )

    objects = CustomUserManager()
    # Govorimo Djangu da koristi email umjesto username-a
    USERNAME_FIELD = 'email'
    REQUIRED_FIELDS = ['first_name', 'last_name']

    def __str__(self):
        return f"{self.first_name} {self.last_name} ({self.email})"

    def clean(self):
        # if self.email == "bot@erp.hr":
        #     return # Preskoči validaciju za bota
        super().clean()
        if self.is_kupac and not self.client_profile:
            raise ValidationError({'client_profile': "Korisnik koji je označen kao kupac mora imati povezan klijentski profil."})

    def save(self, *args, **kwargs):
        self.full_clean() # Prisiljava pokretanje clean() prije svakog save()
        super().save(*args, **kwargs)