from __future__ import annotations
import math
from typing import Optional
import sqlalchemy
from server.model.base import BaseHelper, BaseModel

import sqlalchemy
from sqlalchemy import select, update
from sqlalchemy.orm import mapped_column, relationship, load_only, Mapped

from server.model.chat_complete.bot_persona_category import BotPersonaCategoryModel
from service.database import DatabaseService


class BotPersonaModel(BaseModel):
    __tablename__ = "chat_complete_bot_persona"

    id: Mapped[int] = mapped_column(
        sqlalchemy.Integer, primary_key=True, autoincrement=True
    )
    bot_id: Mapped[str] = mapped_column(sqlalchemy.String(60), index=True)
    bot_name: Mapped[str] = mapped_column(sqlalchemy.String(60), index=True)
    bot_avatar: Mapped[str] = mapped_column(sqlalchemy.String, nullable=True)
    bot_description: Mapped[str] = mapped_column(sqlalchemy.String, nullable=True)
    category_id: Mapped[int] = mapped_column(
        sqlalchemy.ForeignKey(
            BotPersonaCategoryModel.id, ondelete="CASCADE", onupdate="CASCADE"
        ),
        index=True,
    )
    api_id: Mapped[str] = mapped_column(sqlalchemy.String, nullable=True)
    system_prompt: Mapped[str] = mapped_column(sqlalchemy.String)
    message_log: Mapped[list] = mapped_column(sqlalchemy.JSON)
    default_question: Mapped[str] = mapped_column(sqlalchemy.String, nullable=True)
    updated_at: Mapped[int] = mapped_column(sqlalchemy.Integer, index=True)


class BotPersonaHelper(BaseHelper):
    async def add(self, obj: BotPersonaModel):
        self.session.add(obj)
        await self.session.commit()
        await self.session.refresh(obj)
        return obj

    async def update(self, obj: BotPersonaModel):
        obj = await self.session.merge(obj)
        await self.session.commit()
        return obj

    async def get_list(
        self,
        page: Optional[int] = 1,
        page_size: Optional[int] = 20,
        category_id: Optional[int] = None,
    ):
        offset_index = (page - 1) * page_size

        stmt = (
            select(BotPersonaModel)
            .options(
                load_only(
                    BotPersonaModel.id,
                    BotPersonaModel.bot_id,
                    BotPersonaModel.bot_name,
                    BotPersonaModel.bot_avatar,
                    BotPersonaModel.bot_description,
                    BotPersonaModel.updated_at,
                )
            )
            .order_by(BotPersonaModel.updated_at.desc())
            .offset(offset_index)
            .limit(page_size)
        )

        if category_id is not None:
            stmt = stmt.where(BotPersonaModel.category_id == category_id)

        return await self.session.scalars(stmt)

    async def get_page_count(self, page_size=50, category_id: Optional[int] = None):
        stmt = select(sqlalchemy.func.count()).select_from(BotPersonaModel)

        if category_id is not None:
            stmt = stmt.where(BotPersonaModel.category_id == category_id)

        item_count = await self.session.scalar(stmt)
        if item_count is None:
            item_count = 0

        return int(math.ceil(item_count / page_size))

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

    async def find_by_bot_id(self, bot_id: str):
        stmt = select(BotPersonaModel).where(BotPersonaModel.bot_id == bot_id)
        return await self.session.scalar(stmt)

    async def get_system_prompt(self, bot_id: str) -> str | None:
        stmt = select(BotPersonaModel.system_prompt).where(
            BotPersonaModel.bot_id == bot_id
        )
        return await self.session.scalar(stmt)

    @staticmethod
    async def get_cached_system_prompt(dbs: DatabaseService, bot_id: str) -> str | None:
        async with BotPersonaHelper(dbs) as bot_persona_helper:
            return await bot_persona_helper.get_system_prompt(bot_id)