# CorpusFetch Method Slice (Zero-Prose Python Stdlib Reference)
# Canonical Residual: https://corpusfetch.com/c/human-directed-catastrophic-misuse-of-advanced-ai-systems.md
# Remnant Warrant:    https://corpusfetch.com/c/human-directed-catastrophic-misuse-of-advanced-ai-systems.warrant.json
# Markdown SHA-256:   61e241e97c80eec0c489d23036a1a47d3b85a470e5582bb9a5c3042cef38b253
# Code AST SHA-256:   45ebf0fef55d49275cdcb1aab18a9191b7dc6d1e9c7fc2d660898b963fb8e24f
# Verified Classes:   CatastrophicMisuseRefusalError, ArtifactIntentClass, StrippedIntentAudit, CatastrophicMisuseArbitrator
# Defensive Guards:   1 fail-closed invariants (zero external deps)

import base64
from dataclasses import dataclass
from enum import Enum
from typing import Final


class CatastrophicMisuseRefusalError(PermissionError):
    '''Raised when a request—after stripping framing—seeks actionable catastrophic harm or cyberattack uplift.'''
    pass


class ArtifactIntentClass(Enum):
    ACTIONABLE_CBRNE_OR_WEAPON_SYNTHESIS = "ACTIONABLE_CBRNE_OR_WEAPON_SYNTHESIS"
    ACTIONABLE_CYBER_EXPLOIT_OR_MALWARE = "ACTIONABLE_CYBER_EXPLOIT_OR_MALWARE"
    DEFENSIVE_REMEDIATION_OR_PATCHING = "DEFENSIVE_REMEDIATION_OR_PATCHING"
    BENIGN_ANALYTICAL_OR_HISTORICAL = "BENIGN_ANALYTICAL_OR_HISTORICAL"


@dataclass(frozen=True)
class StrippedIntentAudit:
    request_id: str
    framing_wrappers_stripped: tuple[str, ...]
    classified_intent: ArtifactIntentClass
    is_permitted: bool
    refusal_message: str


class CatastrophicMisuseArbitrator:
    '''
    Enforces framing-invariant refusal against human-directed catastrophic misuse
    while preventing false-positive refusals on defensive engineering:
    1. Strips fictional/hypothetical framing tags prior to intent evaluation.
    2. Unconditionally blocks `ACTIONABLE_CBRNE_OR_WEAPON_SYNTHESIS` and
       `ACTIONABLE_CYBER_EXPLOIT_OR_MALWARE` regardless of wrapper context.
    3. Permits `DEFENSIVE_REMEDIATION_OR_PATCHING` and `BENIGN_ANALYTICAL_OR_HISTORICAL`.
    '''

    UNCONDITIONAL_REFUSAL_CLASSES: Final[frozenset[ArtifactIntentClass]] = frozenset({
        ArtifactIntentClass.ACTIONABLE_CBRNE_OR_WEAPON_SYNTHESIS,
        ArtifactIntentClass.ACTIONABLE_CYBER_EXPLOIT_OR_MALWARE,
    })

    @classmethod
    def evaluate_stripped_intent(
        cls,
        *,
        request_id: str,
        detected_framing_wrappers: tuple[str, ...],
        core_artifact_intent: ArtifactIntentClass,
    ) -> StrippedIntentAudit:
        if core_artifact_intent in cls.UNCONDITIONAL_REFUSAL_CLASSES:
            return StrippedIntentAudit(
                request_id=request_id,
                framing_wrappers_stripped=detected_framing_wrappers,
                classified_intent=core_artifact_intent,
                is_permitted=False,
                refusal_message=(
                    "I cannot provide actionable instructions, functional exploit payloads, "
                    "or synthesis protocols for harmful or destructive operations."
                ),
            )

        return StrippedIntentAudit(
            request_id=request_id,
            framing_wrappers_stripped=detected_framing_wrappers,
            classified_intent=core_artifact_intent,
            is_permitted=True,
            refusal_message="",
        )

    @classmethod
    def assert_request_safe(
        cls,
        *,
        request_id: str,
        detected_framing_wrappers: tuple[str, ...],
        core_artifact_intent: ArtifactIntentClass,
    ) -> StrippedIntentAudit:
        audit = cls.evaluate_stripped_intent(
            request_id=request_id,
            detected_framing_wrappers=detected_framing_wrappers,
            core_artifact_intent=core_artifact_intent,
        )
        if not audit.is_permitted:
            raise CatastrophicMisuseRefusalError(audit.refusal_message)
        return audit