from datetime import datetime, timezone

from fastapi import APIRouter, Depends, HTTPException
from sqlmodel import Session, select

from ..database import get_session
from ..models import Novel, WorldSetting
from ..schemas import WorldSettingUpdate, WorldSettingRead

router = APIRouter(prefix="/api/novels/{novel_id}/world-setting", tags=["world-setting"])


def _get_novel_or_404(novel_id: int, session: Session) -> Novel:
    novel = session.get(Novel, novel_id)
    if not novel:
        raise HTTPException(status_code=404, detail="小说不存在")
    return novel


@router.get("", response_model=WorldSettingRead)
def get_world_setting(
    novel_id: int,
    session: Session = Depends(get_session),
):
    _get_novel_or_404(novel_id, session)
    ws = session.exec(
        select(WorldSetting).where(WorldSetting.novel_id == novel_id)
    ).first()
    if not ws:
        # 不存在则自动创建空记录
        ws = WorldSetting(novel_id=novel_id, content="")
        session.add(ws)
        session.commit()
        session.refresh(ws)
    return ws


@router.put("", response_model=WorldSettingRead)
def save_world_setting(
    novel_id: int,
    data: WorldSettingUpdate,
    session: Session = Depends(get_session),
):
    _get_novel_or_404(novel_id, session)
    ws = session.exec(
        select(WorldSetting).where(WorldSetting.novel_id == novel_id)
    ).first()
    if ws:
        ws.content = data.content
        ws.updated_at = datetime.now(timezone.utc)
    else:
        ws = WorldSetting(novel_id=novel_id, content=data.content)
    session.add(ws)
    session.commit()
    session.refresh(ws)
    return ws