"""Shared ChromaDB client factory.

Uses persistent storage on Hugging Face Spaces (/data/chroma) by default.
Set CHROMA_CLIENT_MODE=http for docker-compose with a separate ChromaDB service.
"""

import chromadb

from app.config import get_settings

_client = None


def get_chroma_client():
    """Return a cached ChromaDB client."""
    global _client
    if _client is None:
        cfg = get_settings()
        if cfg.CHROMA_CLIENT_MODE == "http":
            _client = chromadb.HttpClient(
                host=cfg.CHROMA_HOST,
                port=cfg.CHROMA_PORT,
            )
        else:
            _client = chromadb.PersistentClient(path=cfg.CHROMA_PERSIST_DIR)
    return _client