import {
	type CombatantId,
	type DomainError,
	type DomainEvent,
	isDomainError,
	setInitiative,
} from "@initiative/domain";
import type { EncounterStore } from "./ports.js";

export function setInitiativeUseCase(
	store: EncounterStore,
	combatantId: CombatantId,
	value: number | undefined,
): DomainEvent[] | DomainError {
	const encounter = store.get();
	const result = setInitiative(encounter, combatantId, value);

	if (isDomainError(result)) {
		return result;
	}

	store.save(result.encounter);
	return result.events;
}