LilSchool/apps/payment/models.py

from constance import config
from paymentwall import Pingback
from polymorphic.models import PolymorphicModel

from django.db import models
from django.contrib.auth import get_user_model
from django.contrib.postgres.fields import ArrayField, JSONField
from django.core.validators import RegexValidator
from django.utils.timezone import now

from apps.course.models import Course
from apps.school.models import SchoolSchedule
from apps.notification.utils import send_email

User = get_user_model()

CREDIT_CARD_RE = r'^(?:4[0-9]{12}(?:[0-9]{3})?|5[1-5][0-9]{14}|6(?:011|5[0-9][0-9])[0-9]{12}|3[47][0-9]{13}|3(?:0[0-5]|[68][0-9])[0-9]{11}|(?:2131|1800|35\\d{3})\d{11})$'


class AuthorBalance(models.Model):
    IN = 0
    OUT = 1
    TYPE_CHOICES = (
        (IN, 'In'),
        (OUT, 'Out'),
    )
    PENDING = 0
    ACCEPTED = 1
    DECLINED = 2
    STATUS_CHOICES = (
        (PENDING, 'Pending'),
        (ACCEPTED, 'Accepted'),
        (DECLINED, 'Declined'),
    )
    author = models.ForeignKey(User, on_delete=models.CASCADE, verbose_name='Автор',
                               null=True, blank=True, related_name='balances')
    type = models.PositiveSmallIntegerField('Тип', choices=TYPE_CHOICES, default=0)
    amount = models.DecimalField('Итого', max_digits=8, decimal_places=2, default=0)
    commission = models.DecimalField('Комиссия', max_digits=8, decimal_places=2, default=0)
    status = models.PositiveSmallIntegerField('Статус', choices=STATUS_CHOICES, default=0)
    payment = models.OneToOneField('Payment', on_delete=models.CASCADE, null=True, blank=True, verbose_name='Платёж')
    cause = models.TextField('Причина отказа', null=True, blank=True)
    card = models.CharField(max_length=20, validators=[RegexValidator(regex=CREDIT_CARD_RE)], null=True, blank=True)

    declined_send_at = models.DateTimeField(null=True, blank=True)
    created_at = models.DateTimeField(auto_now_add=True)
    update_at = models.DateTimeField(auto_now=True)

    class Meta:
        verbose_name = 'Баланс'
        verbose_name_plural = 'Балансы'

    def save(self, *args, **kwargs):
        self.commission = self.calc_commission()
        if self.type == self.OUT:
            if self.status == self.DECLINED and not self.declined_send_at:
                send_email(
                    'Отказ вывода средств',
                    self.author.email,
                    'notification/email/decline_withdrawal.html',
                    author_balance=self,
                )
                self.declined_send_at = now()
        super().save(*args, **kwargs)

    def calc_commission(self):
        return self.amount * config.SERVICE_COMMISSION / 100


class Payment(PolymorphicModel):
    PW_STATUS_CHOICES = (
        (Pingback.PINGBACK_TYPE_REGULAR, 'regular',),
        (Pingback.PINGBACK_TYPE_GOODWILL, 'goodwill',),
        (Pingback.PINGBACK_TYPE_NEGATIVE, 'negative',),
        (Pingback.PINGBACK_TYPE_RISK_UNDER_REVIEW, 'risk under review',),
        (Pingback.PINGBACK_TYPE_RISK_REVIEWED_ACCEPTED, 'risk reviewed accepted',),
        (Pingback.PINGBACK_TYPE_RISK_REVIEWED_DECLINED, 'risk reviewed declined',),
        (Pingback.PINGBACK_TYPE_RISK_AUTHORIZATION_VOIDED, 'risk authorization voided',),
        (Pingback.PINGBACK_TYPE_SUBSCRIPTION_CANCELLATION, 'subscription cancelation',),
        (Pingback.PINGBACK_TYPE_SUBSCRIPTION_EXPIRED, 'subscription expired',),
        (Pingback.PINGBACK_TYPE_SUBSCRIPTION_PAYMENT_FAILED, 'subscription payment failed',),
    )
    user = models.ForeignKey(User, on_delete=models.CASCADE, verbose_name='Пользователь', related_name='payments')
    amount = models.DecimalField('Итого', max_digits=8, decimal_places=2, default=0, editable=False)
    status = models.PositiveSmallIntegerField('Статус платежа', choices=PW_STATUS_CHOICES, null=True)
    data = JSONField('Данные платежа от провайдера', default={}, editable=False)
    created_at = models.DateTimeField(auto_now_add=True)
    update_at = models.DateTimeField(auto_now=True)

    class Meta:
        verbose_name = 'Платеж'
        verbose_name_plural = 'Платежи'
        ordering = ('created_at',)

    def calc_commission(self):
        return self.amount * config.SERVICE_COMMISSION / 100

    def is_deliverable(self):
        return self.status in [
            Pingback.PINGBACK_TYPE_REGULAR,
            Pingback.PINGBACK_TYPE_GOODWILL,
            Pingback.PINGBACK_TYPE_RISK_REVIEWED_ACCEPTED,
        ]

    def is_under_review(self):
        return self.status == Pingback.PINGBACK_TYPE_RISK_UNDER_REVIEW

    def is_cancelable(self):
        return self.status in [
            Pingback.PINGBACK_TYPE_NEGATIVE,
            Pingback.PINGBACK_TYPE_RISK_REVIEWED_DECLINED,
        ]


class CoursePayment(Payment):
    course = models.ForeignKey(Course, on_delete=models.CASCADE, verbose_name='Курс', related_name='payments')

    class Meta:
        verbose_name = 'Платеж за курс'
        verbose_name_plural = 'Платежи за курсы'

    def save(self, *args, **kwargs):
        self.amount = self.course.price
        super().save(*args, **kwargs)
        author_balance = getattr(self, 'authorbalance', None)
        if not author_balance:
            AuthorBalance.objects.create(
                author=self.course.author,
                amount=self.amount,
                payment=self,
            )
        else:
            author_balance.amount = self.amount
            author_balance.save()


class SchoolPayment(Payment):
    weekdays = ArrayField(models.IntegerField(), size=7, verbose_name='Дни недели')
    date_start = models.DateField('Дата начала подписки', null=True, blank=True)
    date_end = models.DateField('Дата окончания подписки', null=True, blank=True)

    class Meta:
        verbose_name = 'Платеж за школу'
        verbose_name_plural = 'Платежи за школу'

    def __str__(self):
        days = ', '.join([
            dict(SchoolSchedule.WEEKDAY_CHOICES).get(weekday, '')
            for weekday in sorted(self.weekdays)
        ])
        return days

    def save(self, *args, **kwargs):
        aggregate = SchoolSchedule.objects.filter(
            weekday__in=self.weekdays,
        ).aggregate(
            models.Sum('month_price'),
        )
        month_price_sum = aggregate.get('month_price__sum', 0)
        if month_price_sum > config.SERVICE_DISCOUNT_MIN_AMOUNT:
            discount = config.SERVICE_DISCOUNT
        else:
            discount = 0
        self.amount = month_price_sum - discount
        super().save(*args, **kwargs)