import hashlib

from django.contrib.auth.models import AbstractUser
from django.utils.http import urlencode

from judge.models import Profile
from judge.utils.unicode import utf8bytes
from . import registry


@registry.function
def gravatar(email, size=80, default=None):
    if isinstance(email, Profile):
        if default is None:
            default = email.mute
        email = email.user.email
    elif isinstance(email, AbstractUser):
        email = email.email

    gravatar_url = (
        "//www.gravatar.com/avatar/"
        + hashlib.md5(utf8bytes(email.strip().lower())).hexdigest()
        + "?"
    )
    args = {"d": "identicon", "s": str(size)}
    if default:
        args["f"] = "y"
    gravatar_url += urlencode(args)
    return gravatar_url
