"""Illustrative local ledger. No network calls or product SDK dependency."""
from dataclasses import dataclass
from decimal import Decimal
from typing import Iterable


@dataclass(frozen=True)
class Charge:
    event_id: str
    work_id: str
    attempt_id: str
    dollars: Decimal


def summarize(charges: Iterable[Charge], outcomes: dict[str, bool | None]) -> dict:
    """An outcome is True/False only once its predeclared window has closed."""
    unique: dict[str, Charge] = {}
    for charge in charges:
        if not charge.dollars.is_finite() or charge.dollars < 0:
            raise ValueError('Require a finite nonnegative charge')
        if not all((charge.event_id, charge.work_id, charge.attempt_id)):
            raise ValueError('All identifiers are required')
        if charge.event_id in unique and unique[charge.event_id] != charge:
            raise ValueError('Conflicting duplicate event; reconcile before reporting')
        unique[charge.event_id] = charge
    if any(c.work_id not in outcomes for c in unique.values()):
        raise ValueError('A charge has no declared cohort work item')
    if any(value is not None and type(value) is not bool for value in outcomes.values()):
        raise ValueError('Outcome must be true, false, or unknown')
    total = sum((c.dollars for c in unique.values()), Decimal('0'))
    successes = sum(value is True for value in outcomes.values())
    unknown = sum(value is None for value in outcomes.values())
    return {'total_dollars': total, 'successful_items': successes,
            'unknown_items': unknown,
            'dollars_per_success': total / successes if successes and not unknown else None}


if __name__ == '__main__':
    events = [Charge('e1','ticket-1','a1',Decimal('0.03')),
              Charge('e1','ticket-1','a1',Decimal('0.03')),
              Charge('e2','ticket-1','a2',Decimal('0.02')),
              Charge('e3','ticket-2','a3',Decimal('0.05'))]
    print(summarize(events, {'ticket-1': True, 'ticket-2': False}))