# utils/redis_cache.py
import logging
import json
from typing import Any
import config

logger = logging.getLogger(__name__)
_redis = None
_redis_available = None   # None=لم يجرَّب، True=يعمل، False=غير متاح


def get_redis():
    global _redis, _redis_available
    if _redis_available is False:
        return None
    if _redis is not None:
        return _redis
    try:
        import redis
        r = redis.Redis(
            host=config.REDIS_HOST,
            port=config.REDIS_PORT,
            password=config.REDIS_PASSWORD or None,
            db=config.REDIS_DB,
            decode_responses=True,
            socket_connect_timeout=3,
            socket_timeout=3,
        )
        r.ping()
        _redis = r
        _redis_available = True
        logger.info("✅ Redis متصل — الكاش نشط")
        return _redis
    except Exception as e:
        _redis_available = False
        logger.warning(f"⚠️ Redis غير متاح: {e} — سيعمل البوت بكاش ذاكرة فقط")
        return None


# ── كاش الذاكرة الاحتياطي (fallback) ──────────────────────
_mem_cache: dict[str, tuple[Any, float]] = {}


def cache_get(key: str) -> Any | None:
    import time
    r = get_redis()
    if r:
        try:
            val = r.get(key)
            if val:
                return json.loads(val)
            return None
        except Exception:
            pass
    # fallback للذاكرة
    entry = _mem_cache.get(key)
    if entry:
        value, expires_at = entry
        if time.time() < expires_at:
            return value
        del _mem_cache[key]
    return None


def cache_set(key: str, value: Any, ttl: int = None) -> bool:
    import time
    if ttl is None:
        ttl = config.CACHE_TTL   # 20 ساعة افتراضياً
    r = get_redis()
    if r:
        try:
            r.setex(key, ttl, json.dumps(value, ensure_ascii=False))
            return True
        except Exception:
            pass
    # fallback للذاكرة
    _mem_cache[key] = (value, time.time() + ttl)
    # تنظيف الكاش القديم إذا كبر
    if len(_mem_cache) > 500:
        now = time.time()
        expired = [k for k, (_, exp) in _mem_cache.items() if now > exp]
        for k in expired:
            _mem_cache.pop(k, None)
    return True


def cache_delete(key: str) -> bool:
    r = get_redis()
    if r:
        try:
            r.delete(key)
        except Exception:
            pass
    _mem_cache.pop(key, None)
    return True


def cache_exists(key: str) -> bool:
    return cache_get(key) is not None