"""fin_transaction 成交流水仓储：按客户查历史流水（规则引擎聚合规则用）。"""
from __future__ import annotations

from datetime import datetime

from sqlalchemy import func, select

from model.fin_transaction import FinTransaction
from repositories.base import BaseRepository


class FinTransactionRepo(BaseRepository):
    model = FinTransaction

    async def list_since(
        self, customer_id: int, since: datetime
    ) -> list[FinTransaction]:
        """查该客户 since 之后的所有成交流水，按成交时间升序。

        供规则引擎聚合规则（R005~R013 等）在内存中做窗口统计。
        """
        stmt = (
            select(FinTransaction)
            .where(
                FinTransaction.customer_id == customer_id,
                FinTransaction.create_time >= since,
            )
            .order_by(FinTransaction.create_time, FinTransaction.id)
        )
        return list((await self.db.scalars(stmt)).all())

    async def get_last_transaction_time(self, customer_id: int) -> datetime | None:
        """该客户最近一笔成交时间（R016 休眠账户激活判定用）。"""
        return await self.db.scalar(
            select(func.max(FinTransaction.create_time)).where(
                FinTransaction.customer_id == customer_id
            )
        )

    async def list_recent(self, customer_id: int, *, limit: int = 20) -> list[FinTransaction]:
        """按客户读取最近成交记录，供投顾上下文摘要使用。"""
        stmt = (
            select(FinTransaction)
            .where(FinTransaction.customer_id == customer_id)
            .order_by(FinTransaction.create_time.desc(), FinTransaction.id.desc())
            .limit(max(1, min(limit, 100)))
        )
        return list((await self.db.scalars(stmt)).all())