"""Externe Cover-/Metadaten-Quellen (Open Library)."""
# SPDX-License-Identifier: Apache-2.0
from __future__ import annotations

import logging
import os
from typing import Optional

import httpx

log = logging.getLogger(__name__)

OL_SEARCH = "https://openlibrary.org/search.json"
OL_COVER = "https://covers.openlibrary.org/b/isbn/{isbn}-L.jpg"
DEFAULT_TIMEOUT = float(os.environ.get("WATCHSTACK_HTTP_TIMEOUT", "8"))


def lookup_book_by_isbn(isbn: str, *, timeout: float = DEFAULT_TIMEOUT) -> Optional[dict]:
    """Sucht Buchdaten anhand ISBN via Open Library."""
    if not isbn:
        return None
    isbn = isbn.strip().replace("-", "").replace(" ", "")
    try:
        with httpx.Client(timeout=timeout) as client:
            r = client.get(OL_SEARCH, params={"isbn": isbn, "limit": 1})
            r.raise_for_status()
            data = r.json()
    except Exception as exc:  # pragma: no cover
        log.warning("Open-Library-Suche fehlgeschlagen: %s", exc)
        return None

    docs = data.get("docs") or []
    if not docs:
        return None
    d = docs[0]
    return {
        "title": d.get("title"),
        "original_title": d.get("title"),
        "author": ", ".join(d.get("author_name") or []) or None,
        "release_year": d.get("first_publish_year"),
        "cover_url": OL_COVER.format(isbn=isbn) if isbn else None,
        "total_pages": d.get("number_of_pages_median"),
        "description": None,  # OL liefert hier keine handliche Kurzbeschreibung
    }


def lookup_book_by_title(title: str, *, timeout: float = DEFAULT_TIMEOUT) -> Optional[dict]:
    """Sucht Buchdaten anhand Titel (Fallback)."""
    if not title:
        return None
    try:
        with httpx.Client(timeout=timeout) as client:
            r = client.get(OL_SEARCH, params={"title": title, "limit": 1})
            r.raise_for_status()
            data = r.json()
    except Exception as exc:  # pragma: no cover
        log.warning("Open-Library-Suche fehlgeschlagen: %s", exc)
        return None
    docs = data.get("docs") or []
    if not docs:
        return None
    d = docs[0]
    isbn = None
    isbns = d.get("isbn") or []
    if isbns:
        isbn = isbns[0]
    return {
        "title": d.get("title"),
        "author": ", ".join(d.get("author_name") or []) or None,
        "release_year": d.get("first_publish_year"),
        "cover_url": OL_COVER.format(isbn=isbn) if isbn else None,
        "total_pages": d.get("number_of_pages_median"),
    }