contracts.parity.ts

import type {
  ErrorCode as ContractErrorCode,
  TaskEventName as ContractEventName,
  TaskPriority as ContractPriority,
  TaskStatus as ContractStatus,
} from '@taskflow/contracts';
import type { ErrorCode } from './common/exceptions/error-codes';
import type { TaskEventName } from './events/task-events';
import type { TaskStatus } from './tasks/entities/task-status.enum';
import type { TaskPriority } from './tasks/entities/task.entity';

/**
 * Compile-time contract conformance. This file emits nothing; it exists so the
 * build FAILS if the backend's enums / codes / event names ever diverge from
 * the shared API contract (`shared/contracts.d.ts`). It's the cheap insurance
 * that keeps "single source of truth" honest without a runtime cost.
 */

type Assert<T extends true> = T;
type Equal<A, B> = [A] extends [B] ? ([B] extends [A] ? true : false) : false;

// `${TaskStatus}` collapses the string enum to its value union for comparison.
type _StatusParity = Assert<Equal<`${TaskStatus}`, ContractStatus>>;
type _PriorityParity = Assert<Equal<TaskPriority, ContractPriority>>;
type _EventParity = Assert<Equal<TaskEventName, ContractEventName>>;
type _ErrorParity = Assert<Equal<`${ErrorCode}`, ContractErrorCode>>;

export {};