from typing import Annotated, List, Optional
from uuid import UUID

from fastapi import APIRouter, Depends, HTTPException, Query, Request
from fastapi.responses import StreamingResponse
from langchain.embeddings.ollama import OllamaEmbeddings
from langchain_openai import OpenAIEmbeddings
from logger import get_logger
from middlewares.auth import AuthBearer, get_current_user
from models.settings import BrainSettings, get_supabase_client
from modules.brain.service.brain_service import BrainService
from modules.chat.controller.chat.brainful_chat import BrainfulChat
from modules.chat.dto.chats import ChatItem, ChatQuestion
from modules.chat.dto.inputs import (
    ChatMessageProperties,
    ChatUpdatableProperties,
    CreateChatProperties,
    QuestionAndAnswer,
)
from modules.chat.entity.chat import Chat
from modules.chat.service.chat_service import ChatService
from modules.user.entity.user_identity import UserIdentity
from modules.user.service.user_usage import UserUsage
from packages.utils.telemetry import maybe_send_telemetry
from vectorstore.supabase import CustomSupabaseVectorStore

logger = get_logger(__name__)

chat_router = APIRouter()

brain_service = BrainService()
chat_service = ChatService()


def init_vector_store(user_id: UUID) -> CustomSupabaseVectorStore:
    """
    Initialize the vector store
    """
    brain_settings = BrainSettings()
    supabase_client = get_supabase_client()
    embeddings = None
    if brain_settings.ollama_api_base_url:
        embeddings = OllamaEmbeddings(
            base_url=brain_settings.ollama_api_base_url
        )  # pyright: ignore reportPrivateUsage=none
    else:
        embeddings = OpenAIEmbeddings()
    vector_store = CustomSupabaseVectorStore(
        supabase_client, embeddings, table_name="vectors", user_id=user_id
    )

    return vector_store


def get_answer_generator(
    chat_id: UUID,
    chat_question: ChatQuestion,
    brain_id: UUID,
    current_user: UserIdentity,
):
    chat_instance = BrainfulChat()

    user_usage = UserUsage(
        id=current_user.id,
        email=current_user.email,
    )

    vector_store = init_vector_store(user_id=current_user.id)

    # Get History only if needed
    if not brain_id:
        history = chat_service.get_chat_history(chat_id)
    else:
        history = []

    # Generic
    brain, metadata_brain = brain_service.find_brain_from_question(
        brain_id, chat_question.question, current_user, chat_id, history, vector_store
    )

    maybe_send_telemetry("question_asked", {"model_name": brain.model})

    gpt_answer_generator = chat_instance.get_answer_generator(
        brain=brain,
        chat_id=str(chat_id),
        model=brain.model,
        temperature=0.1,
        streaming=True,
        prompt_id=chat_question.prompt_id,
        user_id=current_user.id,
        user_email=current_user.email,
    )

    return gpt_answer_generator


@chat_router.get("/chat/healthz", tags=["Health"])
async def healthz():
    return {"status": "ok"}


# get all chats
@chat_router.get("/chat", dependencies=[Depends(AuthBearer())], tags=["Chat"])
async def get_chats(current_user: UserIdentity = Depends(get_current_user)):
    """
    Retrieve all chats for the current user.

    - `current_user`: The current authenticated user.
    - Returns a list of all chats for the user.

    This endpoint retrieves all the chats associated with the current authenticated user. It returns a list of chat objects
    containing the chat ID and chat name for each chat.
    """
    chats = chat_service.get_user_chats(str(current_user.id))
    return {"chats": chats}


# delete one chat
@chat_router.delete(
    "/chat/{chat_id}", dependencies=[Depends(AuthBearer())], tags=["Chat"]
)
async def delete_chat(chat_id: UUID):
    """
    Delete a specific chat by chat ID.
    """

    chat_service.delete_chat_from_db(chat_id)
    return {"message": f"{chat_id}  has been deleted."}


# update existing chat metadata
@chat_router.put(
    "/chat/{chat_id}/metadata", dependencies=[Depends(AuthBearer())], tags=["Chat"]
)
async def update_chat_metadata_handler(
    chat_data: ChatUpdatableProperties,
    chat_id: UUID,
    current_user: UserIdentity = Depends(get_current_user),
):
    """
    Update chat attributes
    """

    chat = chat_service.get_chat_by_id(
        chat_id  # pyright: ignore reportPrivateUsage=none
    )
    if str(current_user.id) != chat.user_id:
        raise HTTPException(
            status_code=403,  # pyright: ignore reportPrivateUsage=none
            detail="You should be the owner of the chat to update it.",  # pyright: ignore reportPrivateUsage=none
        )
    return chat_service.update_chat(chat_id=chat_id, chat_data=chat_data)


# update existing message
@chat_router.put(
    "/chat/{chat_id}/{message_id}", dependencies=[Depends(AuthBearer())], tags=["Chat"]
)
async def update_chat_message(
    chat_message_properties: ChatMessageProperties,
    chat_id: UUID,
    message_id: UUID,
    current_user: UserIdentity = Depends(get_current_user),
):

    chat = chat_service.get_chat_by_id(
        chat_id  # pyright: ignore reportPrivateUsage=none
    )
    if str(current_user.id) != chat.user_id:
        raise HTTPException(
            status_code=403,  # pyright: ignore reportPrivateUsage=none
            detail="You should be the owner of the chat to update it.",  # pyright: ignore reportPrivateUsage=none
        )
    return chat_service.update_chat_message(
        chat_id=chat_id,
        message_id=message_id,
        chat_message_properties=chat_message_properties.dict(),
    )


# create new chat
@chat_router.post("/chat", dependencies=[Depends(AuthBearer())], tags=["Chat"])
async def create_chat_handler(
    chat_data: CreateChatProperties,
    current_user: UserIdentity = Depends(get_current_user),
):
    """
    Create a new chat with initial chat messages.
    """

    return chat_service.create_chat(user_id=current_user.id, chat_data=chat_data)


# add new question to chat
@chat_router.post(
    "/chat/{chat_id}/question",
    dependencies=[
        Depends(
            AuthBearer(),
        ),
    ],
    tags=["Chat"],
)
async def create_question_handler(
    request: Request,
    chat_question: ChatQuestion,
    chat_id: UUID,
    brain_id: Annotated[UUID | None, Query()] = None,
    current_user: UserIdentity = Depends(get_current_user),
):
    try:
        logger.info(
            f"Creating question for chat {chat_id} with brain {brain_id} of type {type(brain_id)}"
        )
        gpt_answer_generator = get_answer_generator(
            chat_id, chat_question, brain_id, current_user
        )

        chat_answer = gpt_answer_generator.generate_answer(
            chat_id, chat_question, save_answer=True
        )

        return chat_answer
    except HTTPException as e:
        raise e


# stream new question response from chat
@chat_router.post(
    "/chat/{chat_id}/question/stream",
    dependencies=[
        Depends(
            AuthBearer(),
        ),
    ],
    tags=["Chat"],
)
async def create_stream_question_handler(
    request: Request,
    chat_question: ChatQuestion,
    chat_id: UUID,
    brain_id: Annotated[UUID | None, Query()] = None,
    current_user: UserIdentity = Depends(get_current_user),
) -> StreamingResponse:

    chat_instance = BrainfulChat()
    chat_instance.validate_authorization(user_id=current_user.id, brain_id=brain_id)

    logger.info(
        f"Creating question for chat {chat_id} with brain {brain_id} of type {type(brain_id)}"
    )

    gpt_answer_generator = get_answer_generator(
        chat_id, chat_question, brain_id, current_user
    )

    try:
        return StreamingResponse(
            gpt_answer_generator.generate_stream(
                chat_id, chat_question, save_answer=True
            ),
            media_type="text/event-stream",
        )

    except HTTPException as e:
        raise e


# get chat history
@chat_router.get(
    "/chat/{chat_id}/history", dependencies=[Depends(AuthBearer())], tags=["Chat"]
)
async def get_chat_history_handler(
    chat_id: UUID,
) -> List[ChatItem]:
    # TODO: RBAC with current_user
    return chat_service.get_chat_history_with_notifications(chat_id)


@chat_router.post(
    "/chat/{chat_id}/question/answer",
    dependencies=[Depends(AuthBearer())],
    tags=["Chat"],
)
async def add_question_and_answer_handler(
    chat_id: UUID,
    question_and_answer: QuestionAndAnswer,
) -> Optional[Chat]:
    """
    Add a new question and anwser to the chat.
    """
    return chat_service.add_question_and_answer(chat_id, question_and_answer)