import uuid

from fastapi import APIRouter, Depends, HTTPException, status
from sqlalchemy import select
from sqlalchemy.ext.asyncio import AsyncSession

from api.database import get_session
from api.models.topic import Topic, TopicStatus
from api.schemas.topic import TopicCreate, TopicRead, TopicUpdate, TopicWithWorkstreams

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


@router.get("/", response_model=list[TopicRead])
async def list_topics(
    status: TopicStatus | None = None,
    session: AsyncSession = Depends(get_session),
) -> list[Topic]:
    q = select(Topic)
    if status:
        q = q.where(Topic.status == status)
    q = q.order_by(Topic.created_at)
    result = await session.execute(q)
    return list(result.scalars().all())


@router.post("/", response_model=TopicRead, status_code=status.HTTP_201_CREATED)
async def create_topic(
    body: TopicCreate,
    session: AsyncSession = Depends(get_session),
) -> Topic:
    topic = Topic(**body.model_dump())
    session.add(topic)
    await session.commit()
    await session.refresh(topic)
    return topic


@router.get("/{topic_id}", response_model=TopicWithWorkstreams)
async def get_topic(
    topic_id: uuid.UUID,
    session: AsyncSession = Depends(get_session),
) -> Topic:
    topic = await session.get(Topic, topic_id)
    if topic is None:
        raise HTTPException(status_code=404, detail="Topic not found")
    return topic


@router.patch("/{topic_id}", response_model=TopicRead)
async def update_topic(
    topic_id: uuid.UUID,
    body: TopicUpdate,
    session: AsyncSession = Depends(get_session),
) -> Topic:
    topic = await session.get(Topic, topic_id)
    if topic is None:
        raise HTTPException(status_code=404, detail="Topic not found")
    for field, value in body.model_dump(exclude_unset=True).items():
        setattr(topic, field, value)
    await session.commit()
    await session.refresh(topic)
    return topic


@router.delete("/{topic_id}", response_model=TopicRead)
async def archive_topic(
    topic_id: uuid.UUID,
    session: AsyncSession = Depends(get_session),
) -> Topic:
    topic = await session.get(Topic, topic_id)
    if topic is None:
        raise HTTPException(status_code=404, detail="Topic not found")
    topic.status = TopicStatus.archived
    await session.commit()
    await session.refresh(topic)
    return topic