"""
nas_dl.py — Anade descargas al NAS Synology via API de Download Station.

Login:   POST /webapi/auth.cgi      (SYNO.API.Auth, version 6, session DownloadStation)
Crear:   POST /webapi/DownloadStation/task.cgi (SYNO.DownloadStation.Task, create)

La URI puede ser un enlace HTTP directo (p. ej. enlace de RealDebrid),
un magnet o una URL de fichero .torrent.
"""
import json
import os
import sys
import urllib.parse
import urllib.request
from pathlib import Path

from dotenv import load_dotenv

load_dotenv(Path(__file__).resolve().parent / ".env")

NAS_HOST = os.getenv("NAS_HOST", "192.168.50.31").strip().rstrip("/")
NAS_PORT = os.getenv("NAS_PORT", "5000").strip()
NAS_USER = os.getenv("NAS_USER", "").strip()
NAS_PASS = os.getenv("NAS_PASS", "").strip()
NAS_HTTPS = os.getenv("NAS_HTTPS", "0").strip() == "1"

BASE = f"{'https' if NAS_HTTPS else 'http'}://{NAS_HOST}:{NAS_PORT}"


def _api(path, params, session=None):
    data = urllib.parse.urlencode(params).encode()
    headers = {"Content-Type": "application/x-www-form-urlencoded"}
    if session:
        headers["Cookie"] = session
    req = urllib.request.Request(f"{BASE}{path}", data=data, headers=headers)
    with urllib.request.urlopen(req, timeout=20) as r:
        return json.loads(r.read().decode())


def login():
    """Devuelve la cookie de sesion DownloadStation o None."""
    if not NAS_USER or not NAS_PASS:
        print("[NAS] Faltan NAS_USER/NAS_PASS en .env")
        return None
    r = _api("/webapi/auth.cgi", {
        "api": "SYNO.API.Auth",
        "version": "6",
        "method": "login",
        "account": NAS_USER,
        "passwd": NAS_PASS,
        "session": "DownloadStation",
        "format": "cookie",
    })
    if r.get("success"):
        # la cookie viene en Set-Cookie; la reconstruimos con el sid devuelto
        sid = r.get("data", {}).get("sid")
        return f"sid={sid}" if sid else None
    print(f"[NAS] Login fallido: {r.get('error')}")
    return None


def add_torrent(uri, session=None):
    """Anade una URI (http/magnet/.torrent) a Download Station."""
    if not session:
        session = login()
    if not session:
        return False
    r = _api("/webapi/DownloadStation/task.cgi", {
        "api": "SYNO.DownloadStation.Task",
        "version": "3",
        "method": "create",
        "uri": uri,
    }, session=session)
    if r.get("success"):
        print(f"[NAS] Tarea anadida: {uri[:80]}")
        return True
    print(f"[NAS] Error al anadir tarea: {r.get('error')}")
    return False


if __name__ == "__main__":
    if len(sys.argv) < 2:
        print("Uso: python nas_dl.py <uri|magnet|enlace>")
        sys.exit(1)
    ok = add_torrent(sys.argv[1])
    sys.exit(0 if ok else 1)