# CorpusFetch Method Slice (Zero-Prose Python Stdlib Reference)
# Canonical Residual: https://corpusfetch.com/c/what-calibration-invariants-must-survive-when-prediction-markets-inform-agent-decisions.md
# Remnant Warrant:    https://corpusfetch.com/c/what-calibration-invariants-must-survive-when-prediction-markets-inform-agent-decisions.warrant.json
# Markdown SHA-256:   c956682d79661505abb20a53137d2fae806806bee7ff61ae97bacee5b0bc1d3e
# Code AST SHA-256:   c899d95deffbd06f887643bed86cc92dcc090266d2aa432904b7dd7e25806e08
# Verified Classes:   MarketVerdict, MarketPrice, CalibrationPolicy, CalibrationManifest, PredictionMarketCalibrationGuard
# Defensive Guards:   0 fail-closed invariants (zero external deps)

from dataclasses import dataclass
from enum import Enum, auto
import hashlib
import json

class MarketVerdict(Enum):
    NO_MARKET_INPUT = auto()
    RAW_PRICE_TRUSTED = auto()
    CALIBRATED_PRICE_APPLIED = auto()
    PRICE_TOO_UNRELIABLE = auto()

@dataclass(frozen=True)
class MarketPrice:
    market_id: str
    raw_price: float
    brier_score: float
    liquidity_depth: float
    manipulation_detected: bool

@dataclass(frozen=True)
class CalibrationPolicy:
    max_trusted_brier: float
    min_liquidity_depth: float
    allow_manipulation: bool

@dataclass(frozen=True)
class CalibrationManifest:
    verdict: MarketVerdict
    calibrated_probability: float | None
    directive: str
    manifest_digest: str

class PredictionMarketCalibrationGuard:
    @staticmethod
    def _hash(data: str) -> str:
        return hashlib.sha256(data.encode("utf-8")).hexdigest()

    @classmethod
    def evaluate_market(
        cls, price: MarketPrice, policy: CalibrationPolicy
    ) -> CalibrationManifest:
        
        # Gate 1: Manipulation
        if price.manipulation_detected and not policy.allow_manipulation:
            return CalibrationManifest(
                verdict=MarketVerdict.PRICE_TOO_UNRELIABLE,
                calibrated_probability=None,
                directive=f"HALT: Market {price.market_id} shows manipulation. Reject price.",
                manifest_digest=cls._hash(f"MANIPULATION:{price.market_id}")
            )

        # Gate 2: Brier score (calibration quality)
        if price.brier_score > policy.max_trusted_brier:
            # Apply calibration adjustment: reduce confidence, widen uncertainty
            adjusted = 0.5 + (price.raw_price - 0.5) * 0.5
            digest = cls._hash(json.dumps({
                "market": price.market_id,
                "raw": f"{price.raw_price:.3f}",
                "brier": f"{price.brier_score:.3f}",
                "adjusted": f"{adjusted:.3f}"
            }, sort_keys=True))
            return CalibrationManifest(
                verdict=MarketVerdict.CALIBRATED_PRICE_APPLIED,
                calibrated_probability=adjusted,
                directive=f"PROCEED: Brier {price.brier_score:.2f} > {policy.max_trusted_brier:.2f}. Discounted to {adjusted:.2f}.",
                manifest_digest=digest
            )

        # Gate 3: Liquidity
        if price.liquidity_depth < policy.min_liquidity_depth:
            # Widen uncertainty for thin markets
            adjusted = 0.5 + (price.raw_price - 0.5) * 0.7
            digest = cls._hash(json.dumps({
                "market": price.market_id,
                "raw": f"{price.raw_price:.3f}",
                "liquidity": f"{price.liquidity_depth:.2f}",
                "adjusted": f"{adjusted:.3f}"
            }, sort_keys=True))
            return CalibrationManifest(
                verdict=MarketVerdict.CALIBRATED_PRICE_APPLIED,
                calibrated_probability=adjusted,
                directive=f"PROCEED: Thin market ({price.liquidity_depth:.2f}), widened to {adjusted:.2f}.",
                manifest_digest=digest
            )

        # Gate 4: Trust raw
        digest = cls._hash(json.dumps({
            "market": price.market_id,
            "raw": f"{price.raw_price:.3f}",
            "brier": f"{price.brier_score:.3f}",
            "liquidity": f"{price.liquidity_depth:.2f}"
        }, sort_keys=True))
        
        return CalibrationManifest(
            verdict=MarketVerdict.RAW_PRICE_TRUSTED,
            calibrated_probability=price.raw_price,
            directive=f"PROCEED: Price {price.raw_price:.3f} trusted (Brier {price.brier_score:.2f}, liquidity {price.liquidity_depth:.2f}).",
            manifest_digest=digest
        )