"""振幅过滤门：回看窗内 range% 须 ≤ 上限（可关）。永期开仓第一关 / 期期共用。"""

from __future__ import annotations

from typing import Any

from ..exchange.candles import AmplitudeHL


def evaluate_amplitude_gate(
    *,
    filter_enabled: bool,
    amp: AmplitudeHL | None,
    max_pct: float,
    hours: float,
) -> dict[str, Any]:
    """
    返回:
      blocked: 过滤开启且未过关（无K线或超限）
      ok: 展示用是否过关（过滤关视为 True）
      reason: 拒开文案（未拒则为 None）
      snapshot: 写入 session._oo_amp 的字典（amp 为 None 时仅含元数据）
    """
    max_p = float(max_pct)
    hrs = float(hours)
    filt = bool(filter_enabled)
    if amp is None:
        snap = {
            "high": None,
            "low": None,
            "mid": None,
            "range_pct": None,
            "hours": hrs,
            "max_pct": max_p,
            "filter_enabled": filt,
            "ok": False if filt else True,
        }
        if filt:
            return {
                "blocked": True,
                "ok": False,
                "reason": f"振幅未过关：无法获取近 {hrs:g}h K 线高低",
                "snapshot": snap,
            }
        return {"blocked": False, "ok": True, "reason": None, "snapshot": snap}

    range_pct = float(amp.range_pct)
    over = range_pct > max_p + 1e-12
    ok = (not filt) or (not over)
    snap = {
        "high": float(amp.high),
        "low": float(amp.low),
        "mid": float(amp.mid),
        "range_pct": range_pct,
        "hours": hrs,
        "max_pct": max_p,
        "filter_enabled": filt,
        "ok": ok,
    }
    if filt and over:
        return {
            "blocked": True,
            "ok": False,
            "reason": (
                f"振幅未过关：{hrs:g}h 内 {range_pct:.2f}% > {max_p:g}%"
            ),
            "snapshot": snap,
        }
    return {"blocked": False, "ok": ok, "reason": None, "snapshot": snap}