"""策略注册表与工厂。

新增策略：实现 Strategy（base.py），在此注册 {name: Class}，前端下拉即可选。
策略构造参数由请求的 params(dict) 以 **kwargs 传入。
"""
from __future__ import annotations

from .base import Strategy
from .macd_cross import MACDCrossStrategy
from .ma_strategies import MACrossStrategy, SingleMAStrategy

STRATEGIES: dict[str, type[Strategy]] = {
    "macd_cross": MACDCrossStrategy,
    "ma_cross": MACrossStrategy,
    "single_ma": SingleMAStrategy,
}


def build_strategy(name: str, params: dict | None) -> Strategy:
    cls = STRATEGIES.get(name)
    if cls is None:
        raise ValueError(f"未知策略: {name}（可用: {', '.join(STRATEGIES)}）")
    kwargs = {k: v for k, v in (params or {}).items()}
    return cls(**kwargs)