import logging
import decimal
import datetime

from . import stripe as uncloud_stripe
import stripe
from .models import PricingPlan, BillingAddress

logger = logging.getLogger(__name__)

eu_countries = ['at', 'be', 'bg', 'ch', 'cy', 'cz', 'hr', 'dk',
                'ee', 'fi', 'fr', 'mc', 'de', 'gr', 'hu', 'ie', 'it',
                'lv', 'lu', 'mt', 'nl', 'po', 'pt', 'ro','sk', 'si', 'es',
                'se', 'gb']

def validate_vat_number(stripe_customer_id, billing_address_id):
    try:
        billing_address = BillingAddress.objects.get(id=billing_address_id)
    except BillingAddress.DoesNotExist as dne:
        billing_address = None
    except BillingAddress.MultipleObjectsReturned as mor:
        billing_address = BillingAddress.objects.filter(id=billing_address_id).order_by('-id').first()
    if billing_address is not None:
        logger.debug("BillingAddress found: %s %s" % (
            billing_address_id, str(billing_address)))
        if billing_address.country.lower().strip() not in eu_countries:
            return {
                "validated_on": "",
                "status": "not_needed"
            }
        if billing_address.vat_number_validated_on and billing_address.vat_number_verified:
            return {
                "validated_on": billing_address.vat_number_validated_on,
                "status": "verified"
            }
        else:
            if billing_address.stripe_tax_id:
                logger.debug("We have a tax id %s" % billing_address.stripe_tax_id)
                tax_id_obj = stripe.Customer.retrieve_tax_id(
                  stripe_customer_id,
                  billing_address.stripe_tax_id,
                )
                if tax_id_obj.verification.status == "verified":
                    logger.debug("Latest status on Stripe=%s. Updating" %
                                 tax_id_obj.verification.status)
                    # update billing address
                    billing_address.vat_number_validated_on = datetime.datetime.now()
                    billing_address.vat_number_verified = True
                    billing_address.save()
                    return {
                        "status": "verified",
                        "validated_on": billing_address.vat_number_validated_on
                    }
                else:
                    billing_address.vat_number_validated_on = datetime.datetime.now()
                    billing_address.vat_number_verified = False
                    billing_address.save()
            else:
                logger.debug("Creating a tax id")
                tax_id_obj = create_tax_id(
                    stripe_customer_id, billing_address_id,
                    "ch_vat" if billing_address.country.lower() == "ch" else "eu_vat",
                )
    else:
        logger.debug("invalid billing address")
        return {
            "status": "invalid billing address",
            "validated_on": ""
        }
    return {
        "status": tax_id_obj.verification.status if 'verification' in tax_id_obj else "unknown",
        "validated_on": datetime.datetime.now() if tax_id_obj.verification.status == "verified" else ""
    }

def create_tax_id(stripe_customer_id, billing_address_id, type):
    try:
        billing_address = BillingAddress.objects.get(id=billing_address_id)
    except BillingAddress.DoesNotExist as dne:
        billing_address = None
        logger.debug("BillingAddress does not exist for %s" % billing_address_id)
    except BillingAddress.MultipleObjectsReturned as mor:
        logger.debug("Multiple BillingAddress exist for %s" % billing_address_id)
        billing_address = BillingAddress.objects.filter(billing_address_id).order_by('-id').first()

    tax_id_obj = None
    if billing_address:
        try:
            tax_id_obj = uncloud_stripe.get_or_create_tax_id_for_user(
                stripe_customer_id,
                vat_number=billing_address.vat_number,
                type=type,
                country=billing_address.country
            )
            billing_address.stripe_tax_id = tax_id_obj.id
            billing_address.vat_number_verified = True if tax_id_obj.verification.status == "verified" else False
            billing_address.save()
            return tax_id_obj
        except Exception as e:
            logger.debug("Received none in tax_id_obj")
            return {
                'verification': None,
                'error': str(e)
            }

def apply_vat_discount(subtotal, pricing_plan, vat_rate=False, vat_validation_status=False):
    vat_percent = vat_rate
    if pricing_plan.vat_inclusive or (vat_validation_status and vat_validation_status in ["verified", "not_needed"]):
        vat_percent = decimal.Decimal(0)
        vat = decimal.Decimal(0)
    else:
        vat = subtotal * decimal.Decimal(vat_rate) * decimal.Decimal(0.01)
    discount_amount = 0
    discount_amount_with_vat = 0
    if pricing_plan.discount_amount:
        discount_amount = round(float(pricing_plan.discount_amount), 2)
        discount_amount_with_vat = decimal.Decimal(discount_amount) * (1 + decimal.Decimal(vat_rate) * decimal.Decimal(0.01))
        discount_amount_with_vat = discount_amount_with_vat
    
    subtotal = round(float(subtotal), 2)
    vat_percent = round(float(vat_percent), 2)
    discount = {
        'name': pricing_plan.discount_name or 'Discount',
        'amount': discount_amount,
        'amount_with_vat': round(float(discount_amount_with_vat), 2)
    }
    subtotal_after_discount = subtotal - discount["amount"]
    vat_amount = round(vat_percent * 0.01 * subtotal_after_discount, 2)
    price_after_discount_with_vat = round((subtotal - discount['amount']) * (1 + vat_percent * 0.01), 2)

    return (subtotal, round(float(subtotal_after_discount), 2), price_after_discount_with_vat, 
            round(float(vat), 2), vat_percent, vat_amount, discount)


def get_order_total_with_vat(cores, memory, storage,
                          pricing_name='default', vat_rate=False, vat_validation_status=False):
    try:
        pricing = PricingPlan.objects.get(name=pricing_name)
    except Exception as ex:
        logger.error(
            "Error getting PricingPlan object for {pricing_name}."
            "Details: {details}".format(
                pricing_name=pricing_name, details=str(ex)
            )
        )
        return None
    recurring_price = (decimal.Decimal(cores) * pricing.cores_unit_price) + \
                    (decimal.Decimal(memory) * pricing.ram_unit_price) + \
                    (decimal.Decimal(storage) * (pricing.storage_unit_price))
    subtotal = pricing.set_up_fees + recurring_price 
    subtotal, subtotal_after_discount, price_after_discount_with_vat, vat, vat_percent, vat_amount, discount = \
                                    apply_vat_discount(subtotal, pricing, vat_rate, vat_validation_status)
    return {
            "name": pricing.name,
            'recurring_price': round(float(recurring_price), 2),
            "subtotal": subtotal, 
            "discount": discount, 
            "vat": vat, "vat_percent": vat_percent,
            'vat_amount': vat_amount,
            "vat_validation_status": vat_validation_status,
            "subtotal_after_discount": subtotal_after_discount,
            "total": price_after_discount_with_vat
        }