import os
from pathlib import Path
import json
import httpx
from langchain_ollama import OllamaEmbeddings
from langchain_chroma import Chroma
from langchain_text_splitters import RecursiveCharacterTextSplitter

CHROMA_PATH = Path("./chroma_faq")

# Load FAQ markdown files into ChromaDB
def load_faq_to_chroma(md_dir: str = "data"):
    Path(md_dir).mkdir(parents=True, exist_ok=True)
    md_files = list(Path(md_dir).glob("*.md"))
    if not md_files:
        raise FileNotFoundError(f"No .md files found in {md_dir}")
    texts = []
    for md_file in md_files:
        text = md_file.read_text(encoding="utf-8")
        splitter = RecursiveCharacterTextSplitter(chunk_size=500, chunk_overlap=50)
        texts.extend(splitter.split_text(text))
    embeddings = OllamaEmbeddings(model="nomic-embed-text")
    chroma = Chroma(persist_directory=str(CHROMA_PATH), embedding_function=embeddings)
    chroma.add_texts(texts)
    chroma.persist()
    return chroma

# Search the ChromaDB for relevant documents
def search_course_docs(query: str, k: int = 3):
    chroma = Chroma(persist_directory=str(CHROMA_PATH), embedding_function=OllamaEmbeddings(model="nomic-embed-text"))
    retriever = chroma.as_retriever(search_kwargs={"k": k})
    return retriever.get_relevant_documents(query)

# MCP‑style tool: fetch metadata from a mock HTTP endpoint
# In production this would be a real MCP server. Here we use a local JSON file served by http.server.
def fetch_course_meta(query: str):
    url = f"http://localhost:8000/course_meta.json"
    try:
        response = httpx.get(url, timeout=5.0)
        response.raise_for_status()
        data = response.json()
    except Exception:
        # Fallback to local static file if server not running
        data = json.loads(Path("data/course_meta.json").read_text(encoding="utf-8"))
    # Simple filtering: return items where query is in title or description
    results = [item for item in data if query.lower() in item.get("title", "").lower() or query.lower() in item.get("description", "").lower()]
    return results