"""
RAG tools for the ADK agent.
The agent calls these tools to get context from uploaded PDFs.
"""
from rag import get_context_for_query

RAG_TOP_K = 8


def query_uploaded_documents(query: str) -> str:
    """
    Retrieve relevant passages from the user's uploaded PDF documents
    for a given question or topic.
    Call this whenever the user asks about the content of their documents.
    """
    if not query or not str(query).strip():
        return "Please provide a non-empty question or topic to search the documents."
    context = get_context_for_query(query.strip(), top_k=RAG_TOP_K)
    if not context or not context.strip():
        return (
            "No documents have been indexed yet, or no relevant passages were found. "
            "Ask the user to upload and index PDFs first, or try a different query."
        )
    return context