#!/usr/bin/env python3
"""
IWZ Ferienwohnungen - erzeugt einen befristeten, signierten Vorschau-Link
fuer die per Bunny Token Authentication geschuetzte Pull Zone.
"""

import base64
import hashlib
import sys
import time
from pathlib import Path

PROJECT_ROOT = Path(__file__).resolve().parent
GUELTIGKEIT_SEKUNDEN = 7 * 24 * 60 * 60  # 7 Tage
URL_PATH = "/"


def load_env(path):
    env = {}
    if not path.exists():
        return env
    for line in path.read_text(encoding="utf-8").splitlines():
        line = line.strip()
        if not line or line.startswith("#") or "=" not in line:
            continue
        key, value = line.split("=", 1)
        env[key.strip()] = value.strip()
    return env


def build_signed_url(pull_zone_url, auth_key, url_path, expires):
    hashable = f"{auth_key}{url_path}{expires}"
    token_hash = hashlib.sha256(hashable.encode()).digest()
    token = base64.urlsafe_b64encode(token_hash).decode().rstrip("=")
    return f"{pull_zone_url}{url_path}?token={token}&expires={expires}"


if __name__ == "__main__":
    env = load_env(PROJECT_ROOT / ".env")
    pull_zone_url = env.get("BUNNY_PULL_ZONE_URL", "").rstrip("/")
    auth_key = env.get("BUNNY_AUTH_KEY")

    if not pull_zone_url or not auth_key:
        print("\nFEHLER: BUNNY_PULL_ZONE_URL / BUNNY_AUTH_KEY fehlen in .env.")
        print("Siehe .env.example. Auth Key: Pull Zone -> Security -> Token Authentication.")
        sys.exit(1)

    expires = int(time.time()) + GUELTIGKEIT_SEKUNDEN
    link = build_signed_url(pull_zone_url, auth_key, URL_PATH, expires)

    gueltig_bis = time.strftime("%d.%m.%Y %H:%M", time.localtime(expires))
    print("\n=== Vorschau-Link (Bunny Token Authentication) ===\n")
    print(link)
    print(f"\nGueltig bis: {gueltig_bis}\n")