from django.db import models
from django.utils.translation import gettext_lazy as _
from django.core.exceptions import ValidationError


class Sale(models.Model):

    customer = models.CharField(max_length=100)
    date = models.DateField("Date")
    phone = models.CharField(max_length=13, null=True, blank=True)
    description = models.CharField(max_length=255, null=True, blank=True)

    def __str__(self):
        return f"{self.date} {self.customer}"


class SaleLine(models.Model):

    sale = models.ForeignKey(Sale, on_delete=models.CASCADE)
    product = models.CharField(max_length=100)
    quantity = models.IntegerField(null=True)
    unit_price = models.DecimalField(max_digits=9, decimal_places=2)
    description = models.CharField(max_length=255, null=True, blank=True)

    def __str__(self):
        return f"{self.sale} - {self.product}"


class MeasuringUnits(models.TextChoices):
    UNIT = 'UNIT', _('Unit')


class ProductCategory(models.Model):
    name = models.CharField(max_length=100, unique=True)

    def __str__(self):
        return self.name


class Product(models.Model):
    name = models.CharField(max_length=100, unique=True)
    price = models.DecimalField(max_digits=9, decimal_places=2)
    measuring_unit = models.CharField(
        max_length=20,
        choices=MeasuringUnits.choices,
        default=MeasuringUnits.UNIT
    )
    categories = models.ManyToManyField(ProductCategory)

    def __str__(self):
        return self.name


class PyamentMethods(models.TextChoices):
    CASH = 'CASH', _('Cash')
    CONFIAR = 'CONFIAR', _('Confiar')
    BANCOLOMBIA = 'BANCOLOMBIA', _('Bancolombia')


class ReconciliationJarSummary():
    def __init__(self, payments):
        self._validate_payments(payments)
        self._payments = payments

    def _validate_payments(self, payments):
        pass

    @property
    def total(self):
        return sum([p.amount for p in self.payments])

    @property
    def payments(self):
        return self._payments


class ReconciliationJar(models.Model):
    is_valid = models.BooleanField(default=False)
    date_time = models.DateTimeField()
    description = models.CharField(max_length=255, null=True, blank=True)
    reconcilier = models.CharField(max_length=255, null=False, blank=False)
    cash_taken = models.DecimalField(max_digits=9, decimal_places=2)
    cash_discrepancy = models.DecimalField(max_digits=9, decimal_places=2)

    def manual_clean(self):
        payments_amount = sum([p.amount for p in self.payment_set.all()])
        reconciliation_ammount = sum([
            self.cash_taken,
            self.cash_discrepancy,
        ])
        if reconciliation_ammount != payments_amount:
            raise ValidationError(
                {"cash_take": _("The taken ammount has discrepancy.")}
            )
        self.is_valid = True

class Payment(models.Model):
    date_time = models.DateTimeField()
    type_payment = models.CharField(
        max_length=30,
        choices=PyamentMethods.choices,
        default=PyamentMethods.CASH
    )
    amount = models.DecimalField(max_digits=9, decimal_places=2)
    reconciliation_jar = models.ForeignKey(
        ReconciliationJar,
        null=True,
        default=None,
        blank=True,
        on_delete=models.RESTRICT
    )
    description = models.CharField(max_length=255, null=True, blank=True)

    @classmethod
    def get_reconciliation_jar_summary(cls):
        return ReconciliationJarSummary(
            cls.objects.filter(
                type_payment=PyamentMethods.CASH,
                reconciliation_jar=None
            )
        )