from django.db import models
from django.contrib.auth import get_user_model
from django.urls import reverse_lazy

from .helpers import generate_voucher_code
from ..const import PAYMENT_STATUS_SUCCESS, PAYMENT_STATUS_FAILED, PAYMENT_STATUS_REFUNDED
from ..models import InvoicePayment

from clients.models import ClientProfile

from dbsettings.functions import getValue

from datetime import timedelta

import uuid

class Voucher(models.Model):
    code = models.BigIntegerField(default=generate_voucher_code, unique=True)
    value = models.DecimalField(max_digits=10, decimal_places=2)
    created_at = models.DateTimeField(auto_now_add=True)

    @property
    def is_active(self):
        try:
            self.voucheractivation
            return True
        except VoucherActivation.DoesNotExist:
            return False

    def get_absolute_url(self):
        return VoucherDownloadURL.objects.create(voucher=self).get_absolute_url()

class VoucherDownloadURL(models.Model):
    uuid = models.UUIDField(default=uuid.uuid4, primary_key=True)
    voucher = models.ForeignKey(Voucher, models.CASCADE)
    created = models.DateTimeField(auto_now_add=True)

    @property
    def expiry(self):
        return self.created + timedelta(seconds=getValue("payment.voucher.urlvalidity", 300))

    def get_absolute_url(self):
        return reverse_lazy("payment:voucher:download")

class VoucherActivation(models.Model):
    voucher = models.OneToOneField(Voucher, models.PROTECT)
    user = models.ForeignKey(get_user_model(), models.PROTECT)
    activated_at = models.DateTimeField(auto_now_add=True)
    data = models.CharField(max_length=256)

class VoucherApplication(models.Model):
    voucher = models.OneToOneField(Voucher, models.PROTECT)
    client = models.ForeignKey(get_user_model(), models.PROTECT)
    applied_at = models.DateTimeField(auto_now_add=True)

class VoucherInvoicePayment(InvoicePayment):
    success = models.BooleanField(default=True)

    @property
    def gateway(self):
        return "Voucher"

    @classmethod
    def initiate(cls, invoice, amount=None):
        amount = amount or (invoice.balance * -1)

        payment = cls.objects.create(invoice=invoice, amount=amount, gateway_id=uuid.uuid4())

        if invoice.user.balance <= 0:
            payment.success = False
            payment.save()
        
        invoice.finalize()
        return reverse_lazy("payment:status", args=[payment.uuid])

    @property
    def status(self):
        return PAYMENT_STATUS_SUCCESS if self.success else PAYMENT_STATUS_FAILED