"""Plan Engine — Entry / Stop / Target / RR only when Decision is tradable."""

from __future__ import annotations

from crypto_wyckoff.domain_models import DecisionSignal, EngineResult


_TRADABLE = {
    DecisionSignal.STRONG_BUY.value,
    DecisionSignal.BUY.value,
    DecisionSignal.SELL.value,
}


class PlanEngine:
    name = "Plan"
    version = "1.0.0"

    def run(self, daily_feature: EngineResult, decision: EngineResult) -> EngineResult:
        f = daily_feature.payload
        close = float(f.get("close") or 0)
        atr = float(f.get("atr") or 0) or close * 0.02
        swing_low = float(f.get("swing_low") or close - 2 * atr)
        swing_high = float(f.get("swing_high") or close + 2 * atr)
        range_high = float(f.get("range_high") or swing_high)
        signal = decision.payload.get("decision_signal", DecisionSignal.WATCH.value)

        entry = stop = t1 = t2 = rr = None
        reasons: list[str] = []

        if signal not in _TRADABLE or close <= 0:
            reasons.append(f"无交易计划（信号={signal}）")
            return EngineResult(
                name=self.name,
                version=self.version,
                confidence=decision.confidence,
                score=decision.score,
                reasons=reasons,
                payload={
                    "entry": None,
                    "stop": None,
                    "target1": None,
                    "target2": None,
                    "rr": None,
                },
            )

        if signal in (DecisionSignal.STRONG_BUY.value, DecisionSignal.BUY.value):
            entry = round(close, 4)
            stop = round(min(swing_low, close - 1.5 * atr), 4)
            risk = max(entry - stop, 1e-6)
            t1 = round(entry + 2.0 * risk, 4)
            t2 = round(max(range_high, entry + 3.0 * risk), 4)
            rr = round((t1 - entry) / risk, 2)
            reasons.append(f"入场={entry} 止损={stop} 目标一={t1} 盈亏比={rr}")
        else:  # Sell
            entry = round(close, 4)
            stop = round(max(swing_high, close + 1.5 * atr), 4)
            risk = max(stop - entry, 1e-6)
            t1 = round(entry - 2.0 * risk, 4)
            t2 = round(entry - 3.0 * risk, 4)
            rr = round((entry - t1) / risk, 2)
            reasons.append(f"做空计划 入场={entry} 止损={stop} 目标一={t1}")

        return EngineResult(
            name=self.name,
            version=self.version,
            confidence=decision.confidence,
            score=decision.score,
            reasons=reasons,
            payload={
                "entry": entry,
                "stop": stop,
                "target1": t1,
                "target2": t2,
                "rr": rr,
            },
        )