from base64 import urlsafe_b64encode
from hashlib import pbkdf2_hmac
from pathlib import Path

from jinja2_simple_tags import StandaloneTag


class StaticTag(StandaloneTag):
    tags = {"static"}

    def render(self, filename="/", hubapp=None):
        if not hubapp:
            hubapp = self.context["hubapp"]
        elif isinstance(hubapp, str):
            hubapp = self.context["hubapp"].app.get_hubapp_by_name(hubapp)
        return hubapp.uri_from(Path(filename))


def scramble(secret, value):
    if isinstance(value, str):
        value = value.encode()
    if isinstance(secret, str):
        secret = secret.encode()
    return urlsafe_b64encode(
        pbkdf2_hmac("sha512", value, secret, 221100)
    ).rstrip(b"=").decode("ascii")


def get_redis_pass(redis_conf):
    prefix = "requirepass "
    with open(redis_conf, "rt") as fh:
        for line in fh:
            if not line.startswith(prefix):
                continue
            return line[len(prefix) :].rstrip()
    return None