import pickle
import sys
import traceback
from typing import Callable, List, Mapping, Optional, Union

import redis as redis_pkg
import simplejson as json
from flask_caching import Cache
from redis import Redis
from redis.typing import AnyKeyT, EncodableT, ExpiryT, FieldT, KeyT, PatternT, ZScoreBoundT

flask_cache = Cache(config={'CACHE_TYPE': 'RedisCache', 'CACHE_REDIS_URL': 'redis://localhost:6379/15', 'CACHE_KEY_PREFIX': 'local_llm_flask'})

ONE_MONTH_SECONDS = 2678000


class RedisCustom(Redis):
    """
    A wrapper class to set prefixes to keys.
    """

    def __init__(self, prefix, **kwargs):
        super().__init__()
        self.redis = Redis(**kwargs)
        self.prefix = prefix
        try:
            self.set('____', 1)
        except redis_pkg.exceptions.ConnectionError as e:
            print('Failed to connect to the Redis server:', e)
            print('Did you install and start the Redis server?')
            sys.exit(1)

    def _key(self, key):
        return f"{self.prefix}:{key}"

    def set(self, key, value, ex: Union[ExpiryT, None] = None):
        return self.redis.set(self._key(key), value, ex=ex)

    def get(self, key, default=None, dtype=None):
        # TODO: use pickle
        import inspect
        if inspect.isclass(default):
            raise Exception

        d = self.redis.get(self._key(key))
        if dtype and d:
            try:
                if dtype == str:
                    return d.decode('utf-8')
                if dtype in [dict, list]:
                    return json.loads(d.decode("utf-8"))
                else:
                    return dtype(d)
            except:
                traceback.print_exc()
        if not d:
            return default
        else:
            return d

    def incr(self, key, amount=1):
        return self.redis.incr(self._key(key), amount)

    def decr(self, key, amount=1):
        return self.redis.decr(self._key(key), amount)

    def sadd(self, key: str, *values: FieldT):
        return self.redis.sadd(self._key(key), *values)

    def srem(self, key: str, *values: FieldT):
        return self.redis.srem(self._key(key), *values)

    def sismember(self, key: str, value: str):
        return self.redis.sismember(self._key(key), value)

    def lindex(
            self, name: str, index: int
    ):
        return self.redis.lindex(self._key(name), index)

    def lrem(self, name: str, count: int, value: str):
        return self.redis.lrem(self._key(name), count, value)

    def rpush(self, name: str, *values: FieldT):
        return self.redis.rpush(self._key(name), *values)

    def llen(self, name: str):
        return self.redis.llen(self._key(name))

    def zrangebyscore(
            self,
            name: KeyT,
            min: ZScoreBoundT,
            max: ZScoreBoundT,
            start: Union[int, None] = None,
            num: Union[int, None] = None,
            withscores: bool = False,
            score_cast_func: Union[type, Callable] = float,
    ):
        return self.redis.zrangebyscore(self._key(name), min, max, start, num, withscores, score_cast_func)

    def zremrangebyscore(
            self, name: KeyT, min: ZScoreBoundT, max: ZScoreBoundT
    ):
        return self.redis.zremrangebyscore(self._key(name), min, max)

    def hincrby(
            self, name: str, key: str, amount: int = 1
    ):
        return self.redis.hincrby(self._key(name), key, amount)

    def zcard(self, name: KeyT):
        return self.redis.zcard(self._key(name))

    def hdel(self, name: str, *keys: List):
        return self.redis.hdel(self._key(name), *keys)

    def hget(
            self, name: str, key: str
    ):
        return self.redis.hget(self._key(name), key)

    def zadd(
            self,
            name: KeyT,
            mapping: Mapping[AnyKeyT, EncodableT],
            nx: bool = False,
            xx: bool = False,
            ch: bool = False,
            incr: bool = False,
            gt: bool = False,
            lt: bool = False,
    ):
        return self.redis.zadd(self._key(name), mapping, nx, xx, ch, incr, gt, lt)

    def lpush(self, name: str, *values: FieldT):
        return self.redis.lpush(self._key(name), *values)

    def hset(
            self,
            name: str,
            key: Optional = None,
            value=None,
            mapping: Optional[dict] = None,
            items: Optional[list] = None,
    ):
        return self.redis.hset(self._key(name), key, value, mapping, items)

    def hkeys(self, name: str):
        return self.redis.hkeys(self._key(name))

    def hmget(self, name: str, keys: List, *args: List):
        return self.redis.hmget(self._key(name), keys, *args)

    def hgetall(self, name: str):
        return self.redis.hgetall(self._key(name))

    def keys(self, pattern: PatternT = "*", **kwargs):
        raw_keys = self.redis.keys(self._key(pattern), **kwargs)
        keys = []
        for key in raw_keys:
            p = key.decode('utf-8').split(':')
            if len(p) >= 2:
                # Delete prefix
                del p[0]
            k = ':'.join(p)
            if k != '____':
                keys.append(k)
        return keys

    def pipeline(self, transaction=True, shard_hint=None):
        return self.redis.pipeline(transaction, shard_hint)

    def smembers(self, name: str):
        return self.redis.smembers(self._key(name))

    def spop(self, name: str, count: Optional[int] = None):
        return self.redis.spop(self._key(name), count)

    def rpoplpush(self, src, dst):
        return self.redis.rpoplpush(src, dst)

    def zpopmin(self, name: KeyT, count: Union[int, None] = None):
        return self.redis.zpopmin(self._key(name), count)

    def exists(self, *names: KeyT):
        n = []
        for name in names:
            n.append(self._key(name))
        return self.redis.exists(*n)

    def set_dict(self, key: Union[list, dict], dict_value, ex: Union[ExpiryT, None] = None):
        return self.set(key, json.dumps(dict_value), ex=ex)

    def get_dict(self, key):
        r = self.get(key)
        if not r:
            return dict()
        else:
            return json.loads(r.decode("utf-8"))

    def setp(self, name, value):
        self.redis.set(name, pickle.dumps(value))

    def getp(self, name: str):
        r = self.redis.get(name)
        if r:
            return pickle.loads(r)
        return r

    def flush(self):
        flushed = []
        for key in self.redis.scan_iter(f'{self.prefix}:*'):
            flushed.append(key)
            self.redis.delete(key)
        return flushed

    def flushall(self, asynchronous: bool = ..., **kwargs) -> bool:
        self.flush()
        return True

    def flushdb(self, asynchronous: bool = ..., **kwargs) -> bool:
        self.flush()
        return True


redis = RedisCustom('local_llm')