"""Chat API endpoints."""
from fastapi import APIRouter, Depends, HTTPException, status
from pydantic import BaseModel
from sqlalchemy.orm import Session
from app.database import get_db
from app.auth import get_current_user
from app.models import User
from app.application.chat_service import ChatService
from app.dependencies import get_chat_service
from typing import Optional, List
import logging

logger = logging.getLogger(__name__)
router = APIRouter(prefix="/chat", tags=["chat"])


class ChatRequest(BaseModel):
    message: str
    chat_id: Optional[str] = None
    # Scope the search to specific documents or a folder
    document_ids: Optional[List[str]] = None  # Ask about specific files
    folder_id: Optional[str] = None           # Ask about all files in a folder


@router.post("/")
async def send_message(
    request: ChatRequest,
    chat_service: ChatService = Depends(get_chat_service),
    current_user: User = Depends(get_current_user)
):
    """Send a chat message, optionally scoped to specific documents or a folder."""
    try:
        result = await chat_service.send_message(
            message=request.message,
            user=current_user,
            chat_id=request.chat_id,
            document_ids=request.document_ids,
            folder_id=request.folder_id
        )
        return result
    except ValueError as e:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail=str(e))
    except Exception as e:
        logger.error(f"Chat error: {e}")
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail=f"Failed to generate response: {str(e)}"
        )


@router.get("/history")
async def get_chat_history(
    chat_service: ChatService = Depends(get_chat_service),
    current_user: User = Depends(get_current_user)
):
    """Get all chat sessions."""
    return await chat_service.get_chat_history(current_user)


@router.get("/{chat_id}")
async def get_chat_messages(
    chat_id: str,
    chat_service: ChatService = Depends(get_chat_service),
    current_user: User = Depends(get_current_user)
):
    """Get all messages in a chat."""
    try:
        return await chat_service.get_chat_messages(chat_id, current_user)
    except ValueError as e:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail=str(e))


@router.delete("/{chat_id}")
async def delete_chat(
    chat_id: str,
    chat_service: ChatService = Depends(get_chat_service),
    current_user: User = Depends(get_current_user)
):
    """Delete a chat."""
    try:
        await chat_service.delete_chat(chat_id, current_user)
        return {"message": "Chat deleted successfully"}
    except ValueError as e:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail=str(e))