Files
initiative/packages/domain/src/toggle-condition.ts

66 lines
1.9 KiB
TypeScript

import type { ConditionId } from "./conditions.js";
import { CONDITION_DEFINITIONS, VALID_CONDITION_IDS } from "./conditions.js";
import type { DomainEvent } from "./events.js";
import type { CombatantId, DomainError, Encounter } from "./types.js";
export interface ToggleConditionSuccess {
readonly encounter: Encounter;
readonly events: DomainEvent[];
}
export function toggleCondition(
encounter: Encounter,
combatantId: CombatantId,
conditionId: ConditionId,
): ToggleConditionSuccess | DomainError {
if (!VALID_CONDITION_IDS.has(conditionId)) {
return {
kind: "domain-error",
code: "unknown-condition",
message: `Unknown condition "${conditionId}"`,
};
}
const targetIdx = encounter.combatants.findIndex((c) => c.id === combatantId);
if (targetIdx === -1) {
return {
kind: "domain-error",
code: "combatant-not-found",
message: `No combatant found with ID "${combatantId}"`,
};
}
const target = encounter.combatants[targetIdx];
const current = target.conditions ?? [];
const isActive = current.includes(conditionId);
let newConditions: readonly ConditionId[] | undefined;
let event: DomainEvent;
if (isActive) {
const filtered = current.filter((c) => c !== conditionId);
newConditions = filtered.length > 0 ? filtered : undefined;
event = { type: "ConditionRemoved", combatantId, condition: conditionId };
} else {
const added = [...current, conditionId];
const order = CONDITION_DEFINITIONS.map((d) => d.id);
added.sort((a, b) => order.indexOf(a) - order.indexOf(b));
newConditions = added;
event = { type: "ConditionAdded", combatantId, condition: conditionId };
}
const updatedCombatants = encounter.combatants.map((c) =>
c.id === combatantId ? { ...c, conditions: newConditions } : c,
);
return {
encounter: {
combatants: updatedCombatants,
activeIndex: encounter.activeIndex,
roundNumber: encounter.roundNumber,
},
events: [event],
};
}