# pipeline.py
import os
import getpass
import pandas as pd
from typing import Optional

from langchain.docstore.document import Document
from langchain.embeddings import HuggingFaceEmbeddings
from langchain.vectorstores import FAISS
from langchain.chains import RetrievalQA

from smolagents import CodeAgent, DuckDuckGoSearchTool, ManagedAgent, LiteLLMModel
import litellm

# We import the chain builders from our separate files
from classification_chain import get_classification_chain
from refusal_chain import get_refusal_chain
from tailor_chain import get_tailor_chain
from cleaner_chain import get_cleaner_chain, CleanerChain

# We also import the relevant RAG logic here or define it directly
# (We define build_rag_chain in this file for clarity)

###############################################################################
# 1) Environment: set up keys if missing
###############################################################################
if not os.environ.get("GEMINI_API_KEY"):
    os.environ["GEMINI_API_KEY"] = getpass.getpass("Enter your Gemini API Key: ")
if not os.environ.get("GROQ_API_KEY"):
    os.environ["GROQ_API_KEY"] = getpass.getpass("Enter your GROQ API Key: ")

###############################################################################
# 2) build_or_load_vectorstore
###############################################################################
def build_or_load_vectorstore(csv_path: str, store_dir: str) -> FAISS:
    if os.path.exists(store_dir):
        print(f"DEBUG: Found existing FAISS store at '{store_dir}'. Loading...")
        embeddings = HuggingFaceEmbeddings(model_name="sentence-transformers/multi-qa-mpnet-base-dot-v1")
        vectorstore = FAISS.load_local(store_dir, embeddings)
        return vectorstore
    else:
        print(f"DEBUG: Building new store from CSV: {csv_path}")
        df = pd.read_csv(csv_path)
        df = df.loc[:, ~df.columns.str.contains('^Unnamed')]
        df.columns = df.columns.str.strip()
        if "Answer" in df.columns:
            df.rename(columns={"Answer": "Answers"}, inplace=True)
        if "Question" not in df.columns and "Question " in df.columns:
            df.rename(columns={"Question ": "Question"}, inplace=True)
        if "Question" not in df.columns or "Answers" not in df.columns:
            raise ValueError("CSV must have 'Question' and 'Answers' columns.")
        docs = []
        for _, row in df.iterrows():
            q = str(row["Question"])
            ans = str(row["Answers"])
            doc = Document(page_content=ans, metadata={"question": q})
            docs.append(doc)
        embeddings = HuggingFaceEmbeddings(model_name="sentence-transformers/multi-qa-mpnet-base-dot-v1")
        vectorstore = FAISS.from_documents(docs, embedding=embeddings)
        vectorstore.save_local(store_dir)
        return vectorstore

###############################################################################
# 3) Build RAG chain for Gemini
###############################################################################
from langchain.llms.base import LLM
def build_rag_chain(llm_model: LiteLLMModel, vectorstore: FAISS) -> RetrievalQA:
    class GeminiLangChainLLM(LLM):
        def _call(self, prompt: str, stop: Optional[list] = None, **kwargs) -> str:
            messages = [{"role": "user", "content": prompt}]
            return llm_model(messages, stop_sequences=stop)
        @property
        def _llm_type(self) -> str:
            return "custom_gemini"
    retriever = vectorstore.as_retriever(search_type="similarity", search_kwargs={"k": 3})
    gemini_as_llm = GeminiLangChainLLM()
    rag_chain = RetrievalQA.from_chain_type(
        llm=gemini_as_llm,
        chain_type="stuff",
        retriever=retriever,
        return_source_documents=True
    )
    return rag_chain

###############################################################################
# 4) Initialize all the separate chains
###############################################################################
# Classification chain
classification_chain = get_classification_chain()
# Refusal chain
refusal_chain = get_refusal_chain()
# Tailor chain
tailor_chain = get_tailor_chain()
# Cleaner chain
cleaner_chain = get_cleaner_chain()

###############################################################################
# 5) Build our vectorstores + RAG chains
###############################################################################
wellness_csv = "AIChatbot.csv"
brand_csv = "BrandAI.csv"
wellness_store_dir = "faiss_wellness_store"
brand_store_dir = "faiss_brand_store"

wellness_vectorstore = build_or_load_vectorstore(wellness_csv, wellness_store_dir)
brand_vectorstore = build_or_load_vectorstore(brand_csv, brand_store_dir)

gemini_llm = LiteLLMModel(model_id="gemini/gemini-pro", api_key=os.environ.get("GEMINI_API_KEY"))
wellness_rag_chain = build_rag_chain(gemini_llm, wellness_vectorstore)
brand_rag_chain = build_rag_chain(gemini_llm, brand_vectorstore)

###############################################################################
# 6) Tools / Agents for web search
###############################################################################
search_tool = DuckDuckGoSearchTool()
web_agent = CodeAgent(tools=[search_tool], model=gemini_llm)
managed_web_agent = ManagedAgent(agent=web_agent, name="web_search", description="Runs web search for you.")
manager_agent = CodeAgent(tools=[], model=gemini_llm, managed_agents=[managed_web_agent])

def do_web_search(query: str) -> str:
    print("DEBUG: Attempting web search for more info...")
    search_query = f"Give me relevant info: {query}"
    response = manager_agent.run(search_query)
    return response

###############################################################################
# 7) Orchestrator: run_with_chain
###############################################################################
def run_with_chain(query: str) -> str:
    print("DEBUG: Starting run_with_chain...")
    # 1) Classify
    class_result = classification_chain.invoke({"query": query})
    classification = class_result.get("text", "").strip()
    print("DEBUG: Classification =>", classification)

    # If OutOfScope => refusal => tailor => return
    if classification == "OutOfScope":
        refusal_text = refusal_chain.run({})
        final_refusal = tailor_chain.run({"response": refusal_text})
        return final_refusal.strip()

    # If Wellness => wellness RAG => if insufficient => web => unify => tailor
    if classification == "Wellness":
        rag_result = wellness_rag_chain({"query": query})
        csv_answer = rag_result["result"].strip()
        if not csv_answer:
            web_answer = do_web_search(query)
        else:
            lower_ans = csv_answer.lower()
            if any(phrase in lower_ans for phrase in ["i do not know", "not sure", "no context", "cannot answer"]):
                web_answer = do_web_search(query)
            else:
                web_answer = ""
        final_merged = cleaner_chain.merge(kb=csv_answer, web=web_answer)
        final_answer = tailor_chain.run({"response": final_merged})
        return final_answer.strip()

    # If Brand => brand RAG => tailor => return
    if classification == "Brand":
        rag_result = brand_rag_chain({"query": query})
        csv_answer = rag_result["result"].strip()
        final_merged = cleaner_chain.merge(kb=csv_answer, web="")
        final_answer = tailor_chain.run({"response": final_merged})
        return final_answer.strip()

    # fallback
    refusal_text = refusal_chain.run({})
    final_refusal = tailor_chain.run({"response": refusal_text})
    return final_refusal.strip()