import itertools
from uuid import uuid4
from django.conf import settings
from django.db import models, transaction
from django.db.models import Sum, F, Count
from django.contrib.auth.models import User
from django.db.models.signals import pre_save, post_save
from django.dispatch import receiver
from django.utils.translation import gettext_lazy as _
from django_ledger.models import (
    VendorModel,
    EntityModel,
    EntityUnitModel,
    ItemModel,
    AccountModel,
    ItemModelAbstract,
    UnitOfMeasureModel,
    CustomerModel,
    ItemModelQuerySet,
)
from django.db.models import Sum
from decimal import Decimal, InvalidOperation
from django.core.exceptions import ValidationError
from phonenumber_field.modelfields import PhoneNumberField
from django.contrib.contenttypes.models import ContentType
from django.utils.timezone import now
from .utilities.financials import get_financial_value, get_total, get_total_financials
from django.db.models import FloatField
from .mixins import LocalizedNameMixin
from django_ledger.models import EntityModel

class CarMake(models.Model, LocalizedNameMixin):
    id_car_make = models.AutoField(primary_key=True)
    name = models.CharField(max_length=255)
    arabic_name = models.CharField(max_length=255)
    logo = models.ImageField(_("logo"), upload_to="car_make", blank=True, null=True)
    is_sa_import = models.BooleanField(default=False)

    def __str__(self):
        return self.name

    class Meta:
        verbose_name = "Make"


class CarModel(models.Model, LocalizedNameMixin):
    id_car_model = models.AutoField(primary_key=True)
    id_car_make = models.ForeignKey(CarMake, models.DO_NOTHING, db_column="id_car_make")
    name = models.CharField(max_length=255)
    arabic_name = models.CharField(max_length=255)

    def __str__(self):
        return self.name

    class Meta:
        verbose_name = "Model"


class CarSerie(models.Model, LocalizedNameMixin):
    id_car_serie = models.AutoField(primary_key=True)
    id_car_model = models.ForeignKey(
        CarModel, models.DO_NOTHING, db_column="id_car_model"
    )
    name = models.CharField(max_length=255)
    arabic_name = models.CharField(max_length=255)
    year_begin = models.IntegerField(blank=True, null=True)
    year_end = models.IntegerField(blank=True, null=True)

    def __str__(self):
        return self.name

    class Meta:
        verbose_name = "Series"


class CarTrim(models.Model, LocalizedNameMixin):
    id_car_trim = models.AutoField(primary_key=True)
    id_car_serie = models.ForeignKey(
        CarSerie, models.DO_NOTHING, db_column="id_car_serie"
    )
    name = models.CharField(max_length=255)
    arabic_name = models.CharField(max_length=255)
    start_production_year = models.IntegerField(blank=True, null=True)
    end_production_year = models.IntegerField(blank=True, null=True)
    id_car_model = models.ForeignKey(CarModel, models.DO_NOTHING, db_column='id_car_model', blank=True, null=True)

    def __str__(self):
        return self.name

    class Meta:
        verbose_name = "Trim"


class CarSpecification(models.Model, LocalizedNameMixin):
    id_car_specification = models.AutoField(primary_key=True)
    name = models.CharField(max_length=255)
    arabic_name = models.CharField(max_length=255)
    id_parent = models.ForeignKey(
        "self", models.DO_NOTHING, db_column="id_parent", blank=True, null=True
    )

    def __str__(self):
        return self.name

    class Meta:
        verbose_name = "Specification"


class CarSpecificationValue(models.Model):
    id_car_specification_value = models.AutoField(primary_key=True)
    id_car_trim = models.ForeignKey(CarTrim, models.DO_NOTHING, db_column="id_car_trim")
    id_car_specification = models.ForeignKey(
        CarSpecification, models.DO_NOTHING, db_column="id_car_specification"
    )
    value = models.CharField(max_length=500)
    unit = models.CharField(max_length=255, blank=True, null=True)

    def __str__(self):
        return f"{self.id_car_specification.name}: {self.value} {self.unit}"

    class Meta:
        verbose_name = "Specification Value"


# Car Model
class CarStatusChoices(models.TextChoices):
    AVAILABLE = "available", _("Available")
    SOLD = "sold", _("Sold")
    HOLD = "hold", _("Hold")
    DAMAGED = "damaged", _("Damaged")
    RESERVED = "reserved", _("Reserved")


class CarStockTypeChoices(models.TextChoices):
    NEW = "new", _("New")
    USED = "used", _("Used")


class DEALER_TYPES(models.TextChoices):
    Owner = "Owner", _("Owner")
    Inventory = "Inventory", _("Inventory")
    Accountent = "Accountent", _("Accountent")
    Sales = "sales", _("Sales")


class AdditionalServices(models.Model):
    name = models.CharField(max_length=255, verbose_name=_("Name"))
    display_name = models.CharField(max_length=255, verbose_name=_("Display Name"))
    description = models.TextField(verbose_name=_("Description"))
    price = models.DecimalField(max_digits=14, decimal_places=2, verbose_name=_("Price"))

    class Meta:
        verbose_name = _("Additional Services")
        verbose_name_plural = _("Additional Services")

    def __str__(self):
        return self.name + " - " + str(self.price)

class Car(models.Model):
    vin = models.CharField(max_length=17, unique=True, verbose_name=_("VIN"))
    dealer = models.ForeignKey(
        "Dealer", models.DO_NOTHING, related_name="cars", verbose_name=_("Dealer")
    )

    vendor = models.ForeignKey(
        "Vendor",
        models.DO_NOTHING,
        null=True,
        blank=True,
        related_name="cars",
        verbose_name=_("Vendor"),
    )
    id_car_make = models.ForeignKey(
        CarMake,
        models.DO_NOTHING,
        db_column="id_car_make",
        null=True,
        blank=True,
        verbose_name=_("Make"),
    )
    id_car_model = models.ForeignKey(
        CarModel,
        models.DO_NOTHING,
        db_column="id_car_model",
        null=True,
        blank=True,
        verbose_name=_("Model"),
    )
    year = models.IntegerField(verbose_name=_("Year"))
    id_car_serie = models.ForeignKey(
        CarSerie,
        models.DO_NOTHING,
        db_column="id_car_serie",
        null=True,
        blank=True,
        verbose_name=_("Series"),
    )
    id_car_trim = models.ForeignKey(
        CarTrim,
        models.DO_NOTHING,
        db_column="id_car_trim",
        null=True,
        blank=True,
        verbose_name=_("Trim"),
    )
    status = models.CharField(
        max_length=10,
        choices=CarStatusChoices.choices,
        default=CarStatusChoices.AVAILABLE,
        verbose_name=_("Status"),
    )
    stock_type = models.CharField(
        max_length=10,
        choices=CarStockTypeChoices.choices,
        default=CarStockTypeChoices.NEW,
        verbose_name=_("Stock Type"),
    )
    remarks = models.TextField(blank=True, null=True, verbose_name=_("Remarks"))
    mileage = models.IntegerField(blank=True, null=True, verbose_name=_("Mileage"))
    receiving_date = models.DateTimeField(verbose_name=_("Receiving Date"))

    class Meta:
        verbose_name = _("Car")
        verbose_name_plural = _("Cars")

    def __str__(self):
        make = self.id_car_make.name if self.id_car_make else "Unknown Make"
        model = self.id_car_model.name if self.id_car_model else "Unknown Model"
        trim = self.id_car_trim.name if self.id_car_trim else "Unknown Trim"
        return f"{self.year} - {make} - {model} - {trim}"

    def is_reserved(self):
        active_reservations = self.reservations.filter(reserved_until__gt=now())
        return active_reservations.exists()

# class CarData(models.Model):
#     vin = models.CharField(max_length=17, unique=True, verbose_name=_("VIN"))
#     make = models.CharField(max_length=255, verbose_name=_("Make"))
#     make_ar = models.CharField(max_length=255, verbose_name=_("Make Arabic"))
#     model = models.CharField(max_length=255, verbose_name=_("Model"))
#     model_ar = models.CharField(max_length=255, verbose_name=_("Model Arabic"))
#     year = models.IntegerField(verbose_name=_("Year"))
#     series = models.CharField(max_length=255,verbose_name=_("Series"))
#     trim = models.CharField(max_length=255,verbose_name=_("Trim"))
#     specs = models.JsonField
#     status = models.CharField(
#         max_length=10,
#         choices=CarStatusChoices,
#         default=CarStatusChoices.AVAILABLE,
#         verbose_name=_("Status")
#     )
#     stock_type = models.CharField(
#         max_length=10,
#         choices=CarStockTypeChoices,
#         default=CarStockTypeChoices.NEW,
#         verbose_name=_("Stock Type")
#     )
#     remarks = models.TextField(blank=True, null=True, verbose_name=_("Remarks"))
#     mileage = models.IntegerField(blank=True, null=True, verbose_name=_("Mileage"))
#     receiving_date = models.DateTimeField(verbose_name=_("Receiving Date"))


class CarReservation(models.Model):
    car = models.ForeignKey('Car', on_delete=models.CASCADE, related_name='reservations', verbose_name=_("Car"))
    reserved_by = models.ForeignKey(User, on_delete=models.CASCADE, related_name='reservations', verbose_name=_("Reserved By"))
    reserved_at = models.DateTimeField(auto_now_add=True, verbose_name=_("Reserved At"))
    reserved_until = models.DateTimeField(verbose_name=_("Reserved Until"))

    def is_active(self):
        return self.reserved_until > now()

    class Meta:
        unique_together = ('car', 'reserved_until')
        ordering = ['-reserved_at']
        verbose_name = _("Car Reservation")
        verbose_name_plural = _("Car Reservations")

# Car Finance Model
class CarFinance(models.Model):
    additional_services = models.ManyToManyField(AdditionalServices, related_name="additional_finances",blank=True)
    car = models.OneToOneField(Car, on_delete=models.CASCADE, related_name='finances')
    cost_price = models.DecimalField(max_digits=14, decimal_places=2, verbose_name=_("Cost Price"))
    selling_price = models.DecimalField(max_digits=14, decimal_places=2, verbose_name=_("Selling Price"))
    discount_amount = models.DecimalField(max_digits=14, decimal_places=2, verbose_name=_("Discount Amount"),
                                          default=Decimal('0.00'))
    # profit_margin = models.DecimalField(max_digits=14,
    #                                     decimal_places=2,
    #                                     verbose_name=_("Profit Margin"),
    #                                     editable=False)
    # vat_amount = models.DecimalField(max_digits=14,
    #                                     decimal_places=2,
    #                                     verbose_name=_("Vat Amount"),
    #                                     editable=False,default=Decimal('0.00'))
    # registration_fee = models.DecimalField(max_digits=14, decimal_places=2, verbose_name=_("Registration Fee"),
    #                                        default=Decimal('0.00'))
    # administration_fee = models.DecimalField(max_digits=14, decimal_places=2, verbose_name=_("Administration Fee"),
    #                                          default=Decimal('0.00'))
    # transportation_fee = models.DecimalField(max_digits=14, decimal_places=2, verbose_name=_("Transportation Fee"),
    #                                          default=Decimal('0.00'))
    # custom_card_fee = models.DecimalField(max_digits=14, decimal_places=2, verbose_name=_("Custom Card Fee"),
    #                                       default=Decimal('0.00'))
    @property
    def total(self):
        """Calculate the total amount including VAT."""
        return get_total(self)
       
    def __str__(self):
        return f"Car: {self.car}, Selling Price: {self.selling_price}"

    # def save(self, *args, **kwargs):        
    #     self.full_clean()
    #     try:
    #         price_after_discount = self.selling_price - self.discount_amount
    #         self.profit_margin = price_after_discount - self.cost_price
    #         self.vat_amount = settings.VAT_RATE
    #     except InvalidOperation as e:
    #         raise ValidationError(_("Invalid decimal operation: %s") % str(e))
    #     super().save(*args, **kwargs)

    class Meta:
        verbose_name = _("Car Financial Details")
        verbose_name_plural = _("Car Financial Details")

class ExteriorColors(models.Model, LocalizedNameMixin):
    name = models.CharField(max_length=255, verbose_name=_("Name"))
    arabic_name = models.CharField(max_length=255, verbose_name=_("Arabic Name"))
    rgb = models.CharField(max_length=24, blank=True, null=True, verbose_name=_("RGB"))

    class Meta:
        verbose_name = _("Exterior Colors")
        verbose_name_plural = _("Exterior Colors")

    def __str__(self):
        return f"{self.name} ({self.rgb})"


class InteriorColors(models.Model, LocalizedNameMixin):
    name = models.CharField(max_length=255, verbose_name=_("Name"))
    arabic_name = models.CharField(max_length=255, verbose_name=_("Arabic Name"))
    rgb = models.CharField(max_length=24, blank=True, null=True, verbose_name=_("RGB"))

    class Meta:
        verbose_name = _("Interior Colors")
        verbose_name_plural = _("Interior Colors")

    def __str__(self):
        return f"{self.name} ({self.rgb})"


# Colors Model
class CarColors(models.Model):
    car = models.ForeignKey("Car", on_delete=models.CASCADE, related_name="colors")
    exterior = models.ForeignKey(
        "ExteriorColors", on_delete=models.CASCADE, related_name="colors"
    )
    interior = models.ForeignKey(
        "InteriorColors", on_delete=models.CASCADE, related_name="colors"
    )

    class Meta:
        verbose_name = _("Color")
        verbose_name_plural = _("Colors")
        unique_together = ("car", "exterior", "interior")

    def __str__(self):
        return f"{self.car} ({self.exterior.name}) ({self.interior.name})"


# Custom Card Model
class CustomCard(models.Model):
    car = models.OneToOneField(Car, on_delete=models.CASCADE, related_name='custom_cards', verbose_name=_("Car"))
    custom_number = models.CharField(max_length=255, verbose_name=_("Custom Number"))
    custom_date = models.DateField(verbose_name=_("Custom Date"))

    class Meta:
        verbose_name = _("Custom Card")
        verbose_name_plural = _("Custom Cards")

    def __str__(self):
        return f"{self.car} - {self.custom_number}"


class CarLocation(models.Model):
    car = models.OneToOneField(
        Car,
        on_delete=models.CASCADE,
        related_name='location',
        verbose_name=_("Car")
    )
    owner = models.ForeignKey(
        'Dealer',
        on_delete=models.CASCADE,
        related_name='owned_cars',
        verbose_name=_("Owner"),
        help_text=_("Dealer who owns the car.")
    )
    showroom = models.ForeignKey(
        'Dealer',
        on_delete=models.CASCADE,
        related_name='showroom_cars',
        verbose_name=_("Showroom"),
        help_text=_("Dealer where the car is displayed (can be the owner).")
    )
    description = models.TextField(
        blank=True,
        null=True,
        verbose_name=_("Description"),
        help_text=_("Optional description about the showroom placement.")
    )
    created_at = models.DateTimeField(
        auto_now_add=True,
        verbose_name=_("Created At")
    )
    updated_at = models.DateTimeField(
        auto_now=True,
        verbose_name=_("Last Updated")
    )

    class Meta:
        verbose_name = _("Car Location")
        verbose_name_plural = _("Car Locations")

    def __str__(self):
        return f"Car: {self.car}, Showroom: {self.showroom}, Owner: {self.owner}"

    def is_owner_showroom(self):
        """
        Returns True if the showroom is the same as the owner.
        """
        return self.owner == self.showroom

# Car Registration Model
class CarRegistration(models.Model):
    car = models.ForeignKey(
        Car,
        on_delete=models.CASCADE,
        related_name="registrations",
        verbose_name=_("Car"),
    )
    plate_number = models.IntegerField(verbose_name=_("Plate Number"))
    text1 = models.CharField(max_length=1, verbose_name=_("Text 1"))
    text2 = models.CharField(max_length=1, verbose_name=_("Text 2"))
    text3 = models.CharField(max_length=1, verbose_name=_("Text 3"))
    registration_date = models.DateTimeField(verbose_name=_("Registration Date"))

    class Meta:
        verbose_name = _("Registration")
        verbose_name_plural = _("Registrations")

    def __str__(self):
        return f"{self.plate_number} - {self.text1} {self.text2} {self.text3}"


# TimestampedModel Abstract Class
class TimestampedModel(models.Model):
    created = models.DateTimeField(auto_now_add=True, verbose_name=_("Created"))
    updated = models.DateTimeField(auto_now=True, verbose_name=_("Updated"))

    class Meta:
        abstract = True

#subscription
class Subscription(models.Model):
    plan = models.CharField(max_length=255)  # e.g. "basic", "premium"
    start_date = models.DateField()
    end_date = models.DateField()
    max_users = models.IntegerField()  # maximum number of users per account
    users = models.ManyToManyField(User, through='SubscriptionUser')  # many-to-many relationship with User model
    is_active = models.BooleanField(default=True)
    def __str__(self):
        return self.plan
class SubscriptionUser(models.Model):
    subscription = models.ForeignKey(Subscription, on_delete=models.CASCADE)
    user = models.ForeignKey(User, on_delete=models.CASCADE)
    def __str__(self):
        return f"{self.subscription} - {self.user}"
    
class SubscriptionPlan(models.Model):
    name = models.CharField(max_length=255)
    description = models.TextField()
    price = models.DecimalField(max_digits=10, decimal_places=2)
    max_users = models.IntegerField()  # maximum number of users per account
    def __str__(self):
        return f"{self.name} - {self.price}"
# Dealer Model
class Dealer(models.Model, LocalizedNameMixin):
    user = models.OneToOneField(User, on_delete=models.CASCADE, related_name="dealer")
    crn = models.CharField(
        max_length=10, verbose_name=_("Commercial Registration Number"),null=True,blank=True
    )
    vrn = models.CharField(max_length=15, verbose_name=_("VAT Registration Number"),null=True,blank=True)
    arabic_name = models.CharField(max_length=255, verbose_name=_("Arabic Name"))
    name = models.CharField(max_length=255, verbose_name=_("English Name"))
    phone_number = PhoneNumberField(region="SA", verbose_name=_("Phone Number"))
    address = models.CharField(
        max_length=200, blank=True, null=True, verbose_name=_("Address")
    )
    logo = models.ImageField(
        upload_to="logos/users", blank=True, null=True, verbose_name=_("Logo")
    )
    parent_dealer = models.ForeignKey(
        "self",
        on_delete=models.SET_NULL,
        blank=True,
        null=True,
        verbose_name=_("Parent Dealer"),
        related_name="sub_dealers",
    )
    dealer_type = models.CharField(
        max_length=255,
        choices=DEALER_TYPES.choices,
        verbose_name=_("Dealer Type"),
        default=DEALER_TYPES.Owner,
    )

    @property
    def get_active_plan(self):
        try:
            return self.user.subscription_set.filter(is_active=True).first()
        except SubscriptionPlan.DoesNotExist:
            return None
    class Meta:
        verbose_name = _("Dealer")
        verbose_name_plural = _("Dealers")        
        permissions = [            
            ('change_dealer_type', 'Can change dealer type'),
        ]

    def __str__(self):
        return self.name
    
    @property
    def get_sub_dealers(self):
        if self.dealer_type == "Owner":
            return self.sub_dealers.all()
        return None
    
    @property
    def is_parent(self):
        return self.dealer_type == "Owner"
    @property
    def get_root_dealer(self):
        return self.parent_dealer if self.parent_dealer else self

# Vendor Model
class Vendor(models.Model, LocalizedNameMixin):
    dealer = models.ForeignKey(Dealer, on_delete=models.CASCADE, related_name="vendors")
    crn = models.CharField(
        max_length=10, unique=True, verbose_name=_("Commercial Registration Number")
    )
    vrn = models.CharField(
        max_length=15, unique=True, verbose_name=_("VAT Registration Number")
    )
    arabic_name = models.CharField(max_length=255, verbose_name=_("Arabic Name"))
    name = models.CharField(max_length=255, verbose_name=_("English Name"))
    contact_person = models.CharField(max_length=100, verbose_name=_("Contact Person"))
    phone_number = PhoneNumberField(region="SA", verbose_name=_("Phone Number"))
    address = models.CharField(
        max_length=200, blank=True, null=True, verbose_name=_("Address")
    )
    logo = models.ImageField(
        upload_to="logos/vendors", blank=True, null=True, verbose_name=_("Logo")
    )

    class Meta:
        verbose_name = _("Vendor")
        verbose_name_plural = _("Vendors")

    def __str__(self):
        return self.name


# Customer Model
class Customer(models.Model):
    dealer = models.ForeignKey(
        Dealer, on_delete=models.CASCADE, related_name="customers"
    )
    first_name = models.CharField(max_length=50, verbose_name=_("First Name"))
    middle_name = models.CharField(
        max_length=50, blank=True, null=True, verbose_name=_("Middle Name")
    )
    last_name = models.CharField(max_length=50, verbose_name=_("Last Name"))
    email = models.EmailField(unique=True, verbose_name=_("Email"))
    national_id = models.CharField(
        max_length=10, unique=True, verbose_name=_("National ID")
    )
    phone_number = PhoneNumberField(
        region="SA", unique=True, verbose_name=_("Phone Number")
    )
    address = models.CharField(
        max_length=200, blank=True, null=True, verbose_name=_("Address")
    )
    created = models.DateTimeField(auto_now_add=True, verbose_name=_("Created"))

    class Meta:
        verbose_name = _("Customer")
        verbose_name_plural = _("Customers")

    def __str__(self):
        middle = f" {self.middle_name}" if self.middle_name else ""
        return f"{self.first_name}{middle} {self.last_name}"

    @property
    def get_full_name(self):
        return f"{self.first_name} {self.middle_name} {self.last_name}"
        



class Organization(models.Model, LocalizedNameMixin):
    dealer = models.ForeignKey(Dealer, on_delete=models.CASCADE, related_name='organizations')
    name = models.CharField(max_length=255, verbose_name=_("Name"))
    arabic_name = models.CharField(max_length=255, verbose_name=_("Arabic Name"))
    crn = models.CharField(max_length=15, verbose_name=_("Commercial Registration Number"))
    vrn = models.CharField(max_length=15, verbose_name=_("VAT Registration Number"))
    phone_number = PhoneNumberField(region='SA', verbose_name=_("Phone Number"))
    address = models.CharField(max_length=200, blank=True, null=True, verbose_name=_("Address"))
    logo = models.ImageField(upload_to="logos", blank=True, null=True, verbose_name=_("Logo"))

    class Meta:
        verbose_name = _("Organization")
        verbose_name_plural = _("Organizations")
    def __str__(self):
        return self.name


class Representative(models.Model, LocalizedNameMixin):
    dealer = models.ForeignKey(Dealer, on_delete=models.CASCADE, related_name='representatives')
    name = models.CharField(max_length=255, verbose_name=_("Name"))
    arabic_name = models.CharField(max_length=255, verbose_name=_("Arabic Name"))
    id_number = models.CharField(max_length=10, verbose_name=_("ID Number"))
    phone_number = PhoneNumberField(region='SA', verbose_name=_("Phone Number"))
    address = models.CharField(max_length=200, blank=True, null=True, verbose_name=_("Address"))
    organization = models.ManyToManyField(Organization, related_name='representatives')

    class Meta:
        verbose_name = _("Representative")
        verbose_name_plural = _("Representatives")

    def __str__(self):
        return self.name


class SaleQuotation(models.Model):
    quotation_number = models.CharField(max_length=10, unique=True)

    STATUS_CHOICES = [
        ("DRAFT", _("Draft")),
        ("CONFIRMED", _("Confirmed")),
        ("CANCELED", _("Canceled")),
    ]
    dealer = models.ForeignKey(
        Dealer, on_delete=models.CASCADE, related_name="sales", null=True
    )
    entity = models.ForeignKey(EntityModel, on_delete=models.CASCADE)
    customer = models.ForeignKey(
        Customer,
        on_delete=models.CASCADE,
        related_name="quotations",
        verbose_name=_("Customer"),
    )
    amount = models.DecimalField(
        decimal_places=2,
        default=Decimal("0.00"),
        max_digits=10,
        verbose_name=_("Amount"),
    )
    remarks = models.TextField(blank=True, null=True, verbose_name=_("Remarks"))
    is_approved = models.BooleanField(default=False)
    # status = models.CharField(
    #     max_length=10, choices=STATUS_CHOICES, default="DRAFT", verbose_name=_("Status")
    # )
    created_at = models.DateTimeField(auto_now_add=True, verbose_name=_("Created At"))
    updated_at = models.DateTimeField(auto_now=True, verbose_name=_("Updated At"))

    @property
    def total_quantity(self):
        total_quantity = self.quotation_cars.aggregate(total=Sum('quantity'))['total']
        return total_quantity or 0

    @property
    def total(self):
        total = self.quotation_cars.aggregate(total_price=Sum(F('car__finances__selling_price') * F('quantity')))
        if not total:
            return 0
        return total["total_price"]
    
    @property
    def total_vat(self):
        if self.total:
            return float(self.total) * 0.15 + float(self.total)
        return 0
        
    # def confirm(self):
    #     """Confirm the quotation and lock financial details."""
    #     if self.status != "DRAFT":
    #         raise ValueError(_("Only draft quotations can be confirmed."))
    #     self.status = "CONFIRMED"
    #     self.save()

    # def cancel(self):
    #     """Cancel the quotation."""
    #     if self.status == "CONFIRMED":
    #         raise ValueError(_("Cannot cancel a confirmed quotation."))
    #     self.status = "CANCELED"
    #     self.save()

    def __str__(self):
        return f"Quotation #{self.quotation_number} for {self.customer}"
    
    @property
    def display_quotation_number(self):
        return f"QN-{self.quotation_number}"
    
    def save(self, *args, **kwargs):
        if not self.quotation_number:
            self.quotation_number = str(next(self._get_quotation_number())).zfill(6)
        super().save(*args, **kwargs)

    @classmethod
    def _get_quotation_number(cls):
        last_quotation = cls.objects.all().order_by('id').last()
        if last_quotation:
            last_quotation_number = int(last_quotation.quotation_number)
        else:
            last_quotation_number = 0
        return itertools.count(last_quotation_number + 1)

class SaleQuotationCar(models.Model):
    quotation = models.ForeignKey(
        SaleQuotation,
        on_delete=models.CASCADE,
        related_name="quotation_cars",
        verbose_name=_("Quotation"),
    )
    car = models.ForeignKey(
        Car,
        on_delete=models.CASCADE,
        verbose_name=_("Car")
    )
    quantity = models.PositiveIntegerField(default=1, verbose_name=_("Quantity"))
   
    @property
    def finance(self):
        return self.car.finances
    @property
    def financial_details(self):
        """
        Retrieve financial details dynamically from CarFinance.
        Returns a dictionary with all financial fields for better access.
        """
        car_finance = self.car.finances
        if not car_finance:
            return None

        return {
            "selling_price": car_finance.selling_price,
            "administration_fee": car_finance.administration_fee,
            "transportation_fee": car_finance.transportation_fee,
            "custom_card_fee": car_finance.custom_card_fee,
            "registration_fee": car_finance.registration_fee,
            "vat_amount": car_finance.vat_amount,
            # "total_amount": car_finance.total,
        }

    @property
    def total(self):
        """
        Calculate total price dynamically based on quantity and selling price.
        """
        if not self.car.finances:
            return Decimal("0.00")
        return self.car.finances.selling_price * self.quantity
    @property
    def total_vat(self):
        """
        Calculate total price dynamically based on quantity and selling price.
        """
        if not self.car.finances:
            return Decimal("0.00")
        price = float(self.car.finances.selling_price * self.quantity)
        return (price * 0.15) + price

    def __str__(self):
        return f"{self.car} - Quotation #{self.quotation.id}"


class SalesOrder(models.Model):
    quotation = models.OneToOneField(
        SaleQuotation,
        on_delete=models.CASCADE,
        related_name="sales_order",
        verbose_name=_("Quotation"),
    )
    created_at = models.DateTimeField(auto_now_add=True, verbose_name=_("Created At"))
    total_amount = models.DecimalField(
        max_digits=14, decimal_places=2, verbose_name=_("Total Amount")
    )

    def __str__(self):
        return f"Sales Order #{self.id} from Quotation #{self.quotation.id}"