"""Statistics and monitoring tools."""
from clients import get_index
from utils.logging import get_logger
from config import AUTO_LINK_THRESHOLD, AUTO_LINK_TOP_K

logger = get_logger(__name__)

def rag_stats() -> str:
    """
    Return RAG database statistics.

    Returns:
        Formatted statistics or error message
    """
    try:
        index = get_index()
        stats = index.describe_index_stats()

        total = stats.get("total_vector_count", 0)

        output = [
            "=== RAG Statistics ===",
            f"Total documents: {total}",
            f"Dimension: {stats.get('dimension', 'N/A')}",
            f"Index fullness: {stats.get('index_fullness', 'N/A')}",
            "",
            "=== Auto-link Settings ===",
            f"Threshold: {AUTO_LINK_THRESHOLD}",
            f"Top-K candidates: {AUTO_LINK_TOP_K}"
        ]

        logger.info(f"Stats retrieved: {total} documents")
        return "\n".join(output)

    except Exception as e:
        logger.error(f"rag_stats failed: {str(e)}", exc_info=True)
        return f"Error: {str(e)}"