import hashlib

from django.conf import settings


def calculate_epay_hash(order, request):
    hashstring = (
        "{merchant_number}{description}11{amount}DKK"
        "{order_id}{accept_url}{cancel_url}{callback_url}{md5_secret}"
    ).format(
        merchant_number=settings.EPAY_MERCHANT_NUMBER,
        description=order.description,
        amount=order.total * 100,
        order_id=order.pk,
        accept_url=order.get_epay_accept_url(request),
        cancel_url=order.get_cancel_url(request),
        callback_url=order.get_epay_callback_url(request),
        md5_secret=settings.EPAY_MD5_SECRET,
    )
    epay_hash = hashlib.md5(hashstring.encode("utf-8")).hexdigest()
    return epay_hash


def validate_epay_callback(query):
    hashstring = ""
    for key, value in query.items():
        if key != "hash":
            hashstring += value
    hash = hashlib.md5(
        (hashstring + settings.EPAY_MD5_SECRET).encode("utf-8")
    ).hexdigest()
    return hash == query["hash"]