src/id/engine/confront.py

"""Confrontation (Section 8.5).

The player pins two prior statements from a character and confronts them. The
engine verifies the contradiction is *real* against that character's ledger
claims (topic/polarity, and engine truth values). A verified contradiction is a
primary crack trigger; a bogus one does nothing. The ledger is the weapon.
"""

from __future__ import annotations

from dataclasses import dataclass

from .ledger import LedgerStore


@dataclass
class ConfrontResult:
    verified: bool
    reason: str
    claim_a: str = ""
    claim_b: str = ""


def verify_confrontation(
    ledger: LedgerStore, character: str, claim_id_a: str, claim_id_b: str
) -> ConfrontResult:
    a = ledger.claim_by_id(character, claim_id_a)
    b = ledger.claim_by_id(character, claim_id_b)
    if a is None or b is None:
        missing = [cid for cid, c in ((claim_id_a, a), (claim_id_b, b)) if c is None]
        return ConfrontResult(False, f"unknown statement id(s): {missing}")
    if a.claim_id == b.claim_id:
        return ConfrontResult(False, "those are the same statement")

    # A real contradiction: same topic, opposite polarity ...
    if a.topic == b.topic and {a.polarity, b.polarity} == {"affirm", "deny"}:
        return ConfrontResult(
            True,
            f"They said both \"{a.proposition}\" and \"{b.proposition}\" about "
            f"{a.topic} — those cannot both be true.",
            a.proposition, b.proposition,
        )
    # ... or one is known-false against ground truth while contradicting the other.
    if (
        a.topic == b.topic
        and "false" in (a.engine_truth_value, b.engine_truth_value)
        and a.proposition != b.proposition
    ):
        return ConfrontResult(
            True,
            f"Their statements about {a.topic} don't square: "
            f"\"{a.proposition}\" vs \"{b.proposition}\".",
            a.proposition, b.proposition,
        )

    return ConfrontResult(
        False,
        "There's no real contradiction between those two statements.",
        a.proposition, b.proposition,
    )