from functools import wraps

from server.cache.base import get_cache
from server.cache.key_getters import get_key_by_specification


def cached(
    ttl: int,
    key: str = None,
    noself: bool = False,
):
    """Cache decorator.
    By default, (key=None) cache key is generated from function name and arguments.
    noself=True means that first argument of function will be excluded from cache key.
    """

    def wrapper(f):
        @wraps(f)
        async def wrapped(*args, **kwargs):
            result = None
            cache_client = get_cache()
            cache_key = key or get_key_by_specification(f, args, kwargs, noself)

            if ttl > 0:
                result = await cache_client.get(cache_key)

            if result is None:
                result = await f(*args, **kwargs)
                await cache_client.set(cache_key, ttl, result)

            return result

        return wrapped

    return wrapper