"""Patreon campaign-ID resolver.

When gallery-dl fails with "Failed to extract campaign ID" on a Patreon
source, call resolve_campaign_id(vanity, cookies_path) to look up the
campaign ID via Patreon's campaigns API. The caller can then retry with
the id-URL form (patreon.com/id:<id>) to bypass the broken vanity lookup.
"""
import asyncio
import http.cookiejar
import logging
import os
from typing import Optional

import aiohttp
from yarl import URL

logger = logging.getLogger(__name__)

_CAMPAIGNS_URL = "https://www.patreon.com/api/campaigns"
_USER_AGENT = (
    "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 "
    "(KHTML, like Gecko) Chrome/122.0.0.0 Safari/537.36"
)
_REQUEST_TIMEOUT_SECONDS = 10.0


def _load_cookie_jar(cookies_path: Optional[str]) -> Optional[aiohttp.CookieJar]:
    """Load a Netscape-format cookie file into an aiohttp CookieJar.

    Returns None if the path is None, the file is missing, or parsing fails.
    Never raises.
    """
    if not cookies_path or not os.path.isfile(cookies_path):
        return None
    try:
        moz = http.cookiejar.MozillaCookieJar(cookies_path)
        moz.load(ignore_discard=True, ignore_expires=True)
    except (OSError, http.cookiejar.LoadError) as e:
        logger.debug(f"Could not load cookies from {cookies_path}: {e}")
        return None

    jar = aiohttp.CookieJar()
    for cookie in moz:
        jar.update_cookies(
            {cookie.name: cookie.value},
            response_url=URL(
                f"https://{cookie.domain.lstrip('.')}/"
            ),
        )
    return jar


async def resolve_campaign_id(
    vanity: str,
    cookies_path: Optional[str],
) -> Optional[str]:
    """Resolve a Patreon vanity (creator slug) to a campaign ID.

    Returns the campaign ID as a string, or None on any failure (network
    error, auth error, empty response, unexpected shape). Never raises.
    """
    jar = _load_cookie_jar(cookies_path)
    headers = {
        "User-Agent": _USER_AGENT,
        "Accept": "application/vnd.api+json",
    }
    params = {
        "filter[vanity]": vanity,
        "fields[campaign]": "name",
    }
    timeout = aiohttp.ClientTimeout(total=_REQUEST_TIMEOUT_SECONDS)

    try:
        async with aiohttp.ClientSession(
            cookie_jar=jar,
            headers=headers,
            timeout=timeout,
        ) as session:
            async with session.get(_CAMPAIGNS_URL, params=params) as resp:
                if resp.status != 200:
                    logger.warning(
                        f"Patreon campaigns API returned HTTP {resp.status} for vanity={vanity}"
                    )
                    return None
                try:
                    payload = await resp.json(content_type=None)
                except (aiohttp.ContentTypeError, ValueError) as e:
                    logger.warning(
                        f"Patreon campaigns API returned non-JSON for vanity={vanity}: {e}"
                    )
                    return None
    except asyncio.TimeoutError:
        logger.warning(f"Patreon campaigns API timed out for vanity={vanity}")
        return None
    except aiohttp.ClientError as e:
        logger.warning(
            f"Patreon campaigns API request failed for vanity={vanity}: "
            f"{type(e).__name__}: {e}"
        )
        return None

    data = payload.get("data") if isinstance(payload, dict) else None
    if not isinstance(data, list) or not data:
        logger.warning(
            f"Patreon campaigns API returned empty/missing data for vanity={vanity}: "
            f"payload keys={list(payload) if isinstance(payload, dict) else type(payload).__name__}"
        )
        return None

    first = data[0] if isinstance(data[0], dict) else None
    campaign_id = first.get("id") if first else None
    if not isinstance(campaign_id, str) or not campaign_id:
        logger.warning(
            f"Patreon campaigns API response missing 'id' for vanity={vanity}: "
            f"first entry keys={list(first) if isinstance(first, dict) else type(first).__name__}"
        )
        return None

    logger.info(f"Resolved Patreon vanity={vanity} → campaign_id={campaign_id}")
    return campaign_id