import re
import time
import logging
import asyncio
import urllib.request
import json
from concurrent.futures import ThreadPoolExecutor
from urllib.parse import quote_plus

logger = logging.getLogger(__name__)

CACHE_TTL = 6 * 3600
_cache: dict = {"data": [], "ts": 0}

PLAYER_API = "https://api.arte.tv/api/player/v2/config/fr/{pid}"
SEARCH_URL = "https://www.arte.tv/fr/search/?q={q}"

GENRE_PAGES = [
    ("Pop & Rock",       "https://www.arte.tv/fr/p/pop-rock/"),
    ("Classique",        "https://www.arte.tv/fr/p/classique/"),
    ("Electro",          "https://www.arte.tv/fr/p/musiques-electroniques/"),
    ("Jazz",             "https://www.arte.tv/fr/p/jazz"),
    ("Arts de la scène", "https://www.arte.tv/fr/p/arts-de-la-scene"),
    ("Hip-hop",          "https://www.arte.tv/fr/p/hip-hop"),
    ("Metal",            "https://www.arte.tv/fr/p/metal"),
    ("Opéra",            "https://www.arte.tv/fr/p/opera"),
    ("World",            "https://www.arte.tv/fr/p/world"),
    ("Baroque",          "https://www.arte.tv/fr/p/musique-baroque/"),
]

EXTRA_PAGES = [
    "https://www.arte.tv/fr/arte-concert/agenda/",
    "https://www.arte.tv/fr/arte-concert/",
]

CATEGORIES = [name for name, _ in GENRE_PAGES]

_HEADERS = {
    "User-Agent": (
        "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 "
        "Chrome/120.0.0.0 Safari/537.36"
    ),
    "RSC": "1",
}

_PROG_RE = re.compile(r"\b(\d{6}-\d{3}-[A-Z])\b")


def _fetch_url(url: str, headers: dict | None = None) -> str:
    req = urllib.request.Request(url, headers=headers or _HEADERS)
    with urllib.request.urlopen(req, timeout=15) as r:
        return r.read().decode("utf-8", errors="replace")


def _prog_ids_from_page(url: str) -> set[str]:
    try:
        return set(_PROG_RE.findall(_fetch_url(url)))
    except Exception as ex:
        logger.warning("Failed to fetch %s: %s", url, ex)
        return set()


def _metadata_for_pid(pid: str) -> dict | None:
    try:
        raw = _fetch_url(
            PLAYER_API.format(pid=pid),
            headers={"User-Agent": _HEADERS["User-Agent"], "Accept": "application/json"},
        )
        data = json.loads(raw)
        attrs = data["data"]["attributes"]
        meta = attrs["metadata"]

        url = (meta.get("link") or {}).get("url") or f"https://www.arte.tv/fr/videos/{pid}/"
        imgs = meta.get("images") or []
        thumbnail = imgs[0]["url"] if imgs else ""
        duration_s = (meta.get("duration") or {}).get("seconds")
        rights = attrs.get("rights") or {}

        return {
            "id": pid,
            "title": meta.get("title") or "",
            "subtitle": meta.get("subtitle") or "",
            "url": url,
            "thumbnail": thumbnail,
            "duration": duration_s,
            "description": meta.get("description") or "",
            "expiry": rights.get("end") or "",
        }
    except Exception as ex:
        logger.debug("Failed to get metadata for %s: %s", pid, ex)
        return None


def _fetch_all_sync() -> list[dict]:
    id_cats: dict[str, list[str]] = {}
    for name, url in GENRE_PAGES:
        ids = _prog_ids_from_page(url)
        logger.info("  %s → %d IDs", name, len(ids))
        for pid in ids:
            id_cats.setdefault(pid, []).append(name)

    all_ids: set[str] = set(id_cats)
    for url in EXTRA_PAGES:
        ids = _prog_ids_from_page(url)
        logger.info("  %s → %d IDs", url.split("/fr/")[1], len(ids))
        all_ids |= ids
    logger.info("Total unique programme IDs: %d", len(all_ids))

    concerts = _resolve_ids(all_ids)
    for c in concerts:
        c["categories"] = id_cats.get(c["id"], [])
    concerts.sort(key=lambda c: c.get("expiry") or "", reverse=True)
    return concerts


def _resolve_ids(ids: set[str], exclude: set[str] | None = None) -> list[dict]:
    to_fetch = ids - (exclude or set())
    with ThreadPoolExecutor(max_workers=10) as pool:
        results = list(pool.map(_metadata_for_pid, sorted(to_fetch)))
    return [c for c in results if c and c.get("title")]


def _search_sync(query: str) -> set[str]:
    url = SEARCH_URL.format(q=quote_plus(query))
    try:
        html = _fetch_url(url)
        return set(_PROG_RE.findall(html))
    except Exception as ex:
        logger.warning("Search failed for %r: %s", query, ex)
        return set()


# ── public API ────────────────────────────────────────────────────────────────

async def get_all_concerts() -> list[dict]:
    now = time.time()
    if _cache["data"] and now - _cache["ts"] < CACHE_TTL:
        return _cache["data"]
    loop = asyncio.get_event_loop()
    data = await loop.run_in_executor(None, _fetch_all_sync)
    if data:
        _cache["data"] = data
        _cache["ts"] = now
    return _cache["data"]


async def fetch_concerts(page: int = 1, search: str = "", page_size: int = 24, category: str = "") -> dict:
    all_c = await get_all_concerts()

    if category:
        all_c = [c for c in all_c if category in (c.get("categories") or [])]

    cached_ids = {c["id"] for c in all_c}

    if search:
        q = search.lower()
        local = [
            c for c in all_c
            if q in (c.get("title") or "").lower()
            or q in (c.get("subtitle") or "").lower()
            or q in (c.get("description") or "").lower()
        ]
        # Remote search only when no category filter (results have no category info)
        if not category:
            loop = asyncio.get_event_loop()
            remote_ids = await loop.run_in_executor(None, _search_sync, search)
            new_ids = remote_ids - cached_ids
            if new_ids:
                extra = await loop.run_in_executor(None, _resolve_ids, new_ids, None)
                local_ids = {c["id"] for c in local}
                for c in extra:
                    if c["id"] not in local_ids:
                        local.append(c)
        filtered = local
    else:
        filtered = all_c

    start = (page - 1) * page_size
    return {
        "concerts": filtered[start : start + page_size],
        "total": len(filtered),
        "page": page,
        "page_size": page_size,
        "pages": max(1, (len(filtered) + page_size - 1) // page_size),
    }


async def invalidate_cache() -> int:
    _cache["ts"] = 0
    data = await get_all_concerts()
    return len(data)