from __future__ import annotations

import uuid
from datetime import datetime
from typing import Any

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

from app.models.detected_change import DetectedChange
from app.models.enums import ChangeType


class DetectedChangeRepository:
    def __init__(self, db: AsyncSession) -> None:
        self.db = db

    async def get_recent_for_source_and_type(
        self, source_id: uuid.UUID, change_type: ChangeType, since: datetime
    ) -> DetectedChange | None:
        """Most recent DetectedChange of this type for this source within
        the cooldown window - used both to flag repeats (lower significance)
        and to suppress exact duplicates (see change_detection_service.py)."""
        result = await self.db.execute(
            select(DetectedChange)
            .where(
                DetectedChange.source_id == source_id,
                DetectedChange.change_type == change_type,
                DetectedChange.created_at >= since,
            )
            .order_by(DetectedChange.created_at.desc())
            .limit(1)
        )
        return result.scalar_one_or_none()

    async def create(self, **kwargs: Any) -> DetectedChange:
        change = DetectedChange(**kwargs)
        self.db.add(change)
        await self.db.flush()
        return change

    async def list_for_company(
        self, company_id: uuid.UUID, limit: int = 100
    ) -> list[DetectedChange]:
        result = await self.db.execute(
            select(DetectedChange)
            .where(DetectedChange.company_id == company_id)
            .order_by(DetectedChange.created_at.desc())
            .limit(limit)
        )
        return list(result.scalars().all())