from fastapi import APIRouter, Depends, HTTPException
from pydantic import BaseModel
from typing import List, Optional
import uuid

from bd import Settings
from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker

from bd.tables.poll import Poll
from bd.tables.question import Question
from bd.tables.choice import Choice
from route.auth_utils import get_current_user

router = APIRouter(tags=["polls"], prefix="/polls")


class ChoiceIn(BaseModel):
    text: str
    position: Optional[int]


class QuestionIn(BaseModel):
    text: str
    type: Optional[str] = "single"
    position: Optional[int]
    choices: Optional[List[ChoiceIn]]


class PollIn(BaseModel):
    title: str
    description: Optional[str]
    questions: Optional[List[QuestionIn]]


def get_session():
    settings = Settings()
    engine = create_engine(settings.DATABASE_URL_syncpg, future=True)
    return sessionmaker(bind=engine, future=True)


@router.post("/", status_code=201)
def create_poll(payload: PollIn, _: object = Depends(get_current_user)):
    Session = get_session()
    with Session() as session:
        poll = Poll(title=payload.title, description=payload.description)
        # polls are anonymous; no author_id stored
        session.add(poll)
        # questions and choices
        if payload.questions:
            for q in payload.questions:
                question = Question(text=q.text, type=q.type or "single", position=q.position, poll=poll)
                session.add(question)
                if q.choices:
                    for idx, c in enumerate(q.choices):
                        choice = Choice(text=c.text, position=c.position if c.position is not None else idx, question=question)
                        session.add(choice)
        session.commit()
        session.refresh(poll)
        return {"id": str(poll.id)}


@router.get("/{poll_id}")
def get_poll(poll_id: str):
    Session = get_session()
    try:
        pid = uuid.UUID(poll_id)
    except Exception:
        raise HTTPException(status_code=400, detail="Invalid UUID")
    with Session() as session:
        poll = session.get(Poll, pid)
        if not poll:
            raise HTTPException(status_code=404, detail="Poll not found")
        data = {
            "id": str(poll.id),
            "title": poll.title,
            "description": poll.description,
            "questions": [
                {
                    "id": str(q.id),
                    "text": q.text,
                    "type": q.type,
                    "choices": [{"id": str(c.id), "text": c.text} for c in q.choices]
                }
                for q in poll.questions
            ],
        }
        return data


@router.get("/")
def list_polls():
    Session = get_session()
    with Session() as session:
        rows = session.query(Poll).all()
        return [{"id": str(p.id), "title": p.title, "description": p.description} for p in rows]