import uuid
from typing import Optional, TypeVar

from ddtrace.trace import tracer
from pydantic import BaseModel

from pdp.connectors.redis_client import PydanticSchemaSerializer, RedisConnector
from pdp.fastapi.schemas.cache import LookupCacheObject
from pdp.utils.cache import DELIMITER_KEY_VAL

T = TypeVar("T")


@tracer.wrap()
async def save_cache_object(
    cache_object: LookupCacheObject,
    cache_model_type: type[BaseModel],
    redis_connector: RedisConnector,
) -> bool:
    """Reusable function logic to save a cache object."""
    if not cache_object.is_valid_to_save():
        return False
    return await redis_connector.set(
        cache_object.to_cache_key(),
        item=cache_object,
        serializer=PydanticSchemaSerializer(cache_model_type),
        ttl=cache_object.get_ttl(),
    )


@tracer.wrap()
async def get_object_from_cache(
    key: str,
    redis_connector: RedisConnector,
    serializer: PydanticSchemaSerializer,
    cache_attribute_name: str,
) -> Optional[T]:
    """Reusable function logic to get an object from cache."""
    result: LookupCacheObject | None = await redis_connector.get(
        key=key, serializer=serializer
    )

    if result is None:
        return None

    # The cache object is a wrapper for the actual cached value.
    # Find the cached value by attribute name and return it.
    return getattr(result, cache_attribute_name, None)


@tracer.wrap()
async def bust_identity_caches(
    identity_uuids: list[uuid.UUID],
    redis_connector: RedisConnector,
) -> None:
    """Reusable function logic to deactivate an identity's cache."""
    if not identity_uuids:
        return

    wildcard_keys = [
        _get_identity_wildcard(identity_uuid) for identity_uuid in identity_uuids
    ]
    for wildcard_key in wildcard_keys:
        await redis_connector.delete_all_matching_pattern(wildcard_key)


def _get_identity_wildcard(identity_uuid: uuid.UUID) -> str:
    """Return wildcard for looking up an identity's cache keys."""
    return f"*identity_uuid{DELIMITER_KEY_VAL}{identity_uuid}*"