dempsters_court/case_state.py

"""Per-session game state."""
from __future__ import annotations
from dataclasses import dataclass, field
from typing import Literal
from .case_loader import CaseData


Method = Literal["dempster", "yager", "pcr5", "cautious"]


@dataclass
class Turn:
    role: str
    content: str


@dataclass
class Deposition:
    witness_id: str
    mass: dict[frozenset[str], float]
    summary: str
    alpha: float = 0.0   # discount


@dataclass
class Verdict:
    suspect: str
    method: Method
    suspicion: float
    threshold: float


@dataclass
class CaseState:
    session_id: str
    case_id: str
    days_remaining: int
    transcripts: dict[str, list[Turn]] = field(default_factory=dict)
    depositions: list[Deposition] = field(default_factory=list)
    active_method: Method = "dempster"
    combined_mass: dict[frozenset[str], float] | None = None
    bel: dict[str, float] | None = None
    pl: dict[str, float] | None = None
    conflict_K: float | None = None
    verdict: Verdict | None = None
    outcome: Literal["just", "wrongful", "cold", "mistrial"] | None = None

    @classmethod
    def start(cls, session_id: str, case: CaseData) -> "CaseState":
        return cls(
            session_id=session_id,
            case_id=case.case_id,
            days_remaining=case.court_days,
            transcripts={w.id: [] for w in case.witnesses},
            active_method=case.methods_available[0],
        )