"""SQLAlchemy-backed per-user custom prompt repository."""

from __future__ import annotations

from datetime import UTC, datetime
from typing import Any

from sqlalchemy import select
from sqlalchemy.ext.asyncio import AsyncSession, async_sessionmaker

from deerflow.persistence.user_prompts.model import UserCustomPromptRow


def _row_to_dict(row: UserCustomPromptRow) -> dict[str, Any]:
    data = row.to_dict()
    for key in ("created_at", "updated_at"):
        value = data.get(key)
        if isinstance(value, datetime):
            data[key] = value.isoformat()
    return data


class UserCustomPromptRepository:
    def __init__(self, session_factory: async_sessionmaker[AsyncSession]) -> None:
        self._sf = session_factory

    async def list_for_user(self, user_id: str) -> list[dict[str, Any]]:
        stmt = (
            select(UserCustomPromptRow)
            .where(UserCustomPromptRow.user_id == user_id)
            .order_by(UserCustomPromptRow.sort_order.asc(), UserCustomPromptRow.created_at.asc())
        )
        async with self._sf() as session:
            result = await session.execute(stmt)
            return [_row_to_dict(row) for row in result.scalars()]

    async def create(self, user_id: str, data: dict[str, Any]) -> dict[str, Any]:
        now = datetime.now(UTC)
        row = UserCustomPromptRow(
            id=data["id"],
            user_id=user_id,
            title=data.get("title") or "",
            content=data["content"],
            sort_order=data.get("sort_order", 0),
            agent_id=(data.get("agent_id") or None),
            created_at=now,
            updated_at=now,
        )
        async with self._sf() as session:
            session.add(row)
            await session.commit()
            await session.refresh(row)
            return _row_to_dict(row)

    async def update(self, prompt_id: str, user_id: str, data: dict[str, Any]) -> dict[str, Any] | None:
        async with self._sf() as session:
            row = await session.get(UserCustomPromptRow, prompt_id)
            if row is None or row.user_id != user_id:
                return None
            for key in ("title", "content", "sort_order"):
                if key in data:
                    setattr(row, key, data[key])
            # ``agent_id`` is explicitly nullable: an empty/None value clears the
            # association (back to global), so accept None as a real update.
            if "agent_id" in data:
                row.agent_id = data["agent_id"] or None
            row.updated_at = datetime.now(UTC)
            await session.commit()
            await session.refresh(row)
            return _row_to_dict(row)

    async def delete(self, prompt_id: str, user_id: str) -> bool:
        async with self._sf() as session:
            row = await session.get(UserCustomPromptRow, prompt_id)
            if row is None or row.user_id != user_id:
                return False
            await session.delete(row)
            await session.commit()
            return True