"""# Summary

Generic MongoDB CRUD repo — single implementation for all domains.

Select a concrete mongo-ops repository (base, cached, or populating) from the
options supplied to the factory.
"""

from mongo_ops import BaseRepository, CachedBaseRepository, PopulatingRepository
from mongo_ops.cache import CacheBackend, CacheConfig
from mongo_ops.models import BaseDocument
from mongo_ops.populate import PopulateRule, PopulationEngine


def _repo_factory(
    collection: str,
    db_model: type[BaseDocument],
    cache_backend: CacheBackend | None = None,
    cache_config: CacheConfig | None = None,
    engine: PopulationEngine | None = None,
    populate_rules: list[PopulateRule] | None = None,
) -> BaseRepository:
    """Build the appropriate mongo-ops repository.

    Args:
        collection (str): Collection name to operate on.
        db_model (Type[BaseDocument]): Document model bound to the collection.
        cache_backend (Optional[CacheBackend]): Cache backend enabling cached reads.
        cache_config (Optional[CacheConfig]): Cache configuration for the backend.
        engine (Optional[PopulationEngine]): Population engine for reference expansion.
        populate_rules (Optional[List[PopulateRule]]): Rules applied by the engine.

    Returns:
        BaseRepository: Repository instance matching the supplied options.
    """
    if engine and populate_rules is not None:
        return PopulatingRepository(collection, db_model, engine, populate_rules)
    elif cache_backend is not None:
        return CachedBaseRepository(collection, db_model, cache_backend, cache_config)
    else:
        return BaseRepository(collection, db_model)