from typing import Optional, Union
import sqlalchemy
from sqlalchemy import select, update, delete
from sqlalchemy.orm import mapped_column, Mapped

from api.model.base import BaseHelper, BaseModel
from service.database import DatabaseService

class TitleCollectionModel(BaseModel):
    __tablename__ = "embedding_search_title_collection"

    id: Mapped[int] = mapped_column(sqlalchemy.Integer, primary_key=True, autoincrement=True)
    title: Mapped[str] = mapped_column(sqlalchemy.String(255), index=True)
    page_id: Mapped[int] = mapped_column(sqlalchemy.Integer, index=True, nullable=True)

class TitleCollectionHelper(BaseHelper):
    async def add(self, title: str, page_id: Optional[int] = None) -> TitleCollectionModel | None:
        stmt = select(TitleCollectionModel.id).where(TitleCollectionModel.title == title)
        result = await self.session.scalar(stmt)

        if result is None:
            obj = TitleCollectionModel(title=title, page_id=page_id)
            self.session.add(obj)
            await self.session.commit()
            await self.session.refresh(obj)
            return obj

        return None

    async def set_main_page_id(self, title: str, page_id: Optional[str] = None):
        stmt = update(TitleCollectionModel).where(TitleCollectionModel.title == title).values(page_id=page_id)
        await self.session.execute(stmt)
        await self.session.commit()

    async def remove(self, title: str):
        stmt = delete(TitleCollectionModel).where(TitleCollectionModel.title == title)
        await self.session.execute(stmt)
        await self.session.commit()

    async def find_by_id(self, id: int):
        stmt = select(TitleCollectionModel).where(TitleCollectionModel.id == id)
        return await self.session.scalar(stmt)

    async def find_by_title(self, title: str):
        stmt = select(TitleCollectionModel).where(TitleCollectionModel.title == title)
        return await self.session.scalar(stmt)

    async def find_by_page_id(self, page_id: int):
        stmt = select(TitleCollectionModel).where(TitleCollectionModel.page_id == page_id)
        return await self.session.scalar(stmt)