"""策略抽象基类。策略只产生买卖意图（向 broker 下单），不负责撮合/费用。"""
from __future__ import annotations

from abc import ABC, abstractmethod

import pandas as pd

from ..broker import PaperBroker


class Strategy(ABC):
    """compute 预算指标；on_bar 逐 bar 决策并向 broker 下单。"""

    @abstractmethod
    def compute(self, close: pd.Series, high: pd.Series, low: pd.Series) -> pd.DataFrame:
        ...

    @abstractmethod
    def on_bar(self, i: int, row: pd.Series, broker: PaperBroker) -> None:
        ...