from django.db import models
from django.utils import timezone

import uuid

from polymorphic.models import PolymorphicModel

from .invoice import Invoice

from ..signals import initiate_payment

class InvoicePayment(PolymorphicModel):
    uuid = models.UUIDField(default=uuid.uuid4)
    invoice = models.ForeignKey(Invoice, models.PROTECT)
    amount = models.DecimalField(max_digits=9, decimal_places=2)
    gateway_id = models.CharField(max_length=256)
    timestamp = models.DateTimeField(default=timezone.now)

    @property
    def gateway(self):
        raise NotImplementedError("%s does not implement gateway" % type(self))

    @property
    def status(self):
        raise NotImplementedError("%s does not implement status" % type(self))

    @classmethod
    def initiate(cls, invoice):
        raise NotImplementedError("%s does not implement initiate()" % cls.__name__)

    def finalize(self, *args, **kwargs):
        return self.invoice.finalize(*args, **kwargs)

    @classmethod
    def from_invoice(cls, invoice, gateway):
        if not invoice.is_paid:
            responses = initiate_payment.send_robust(sender=cls, invoice=invoice, gateway=gateway)
            for handler, response in responses:
                try:
                    return response["redirect"]
                except:
                    continue
        return False