// 只记录入队、不执行的假引擎(处理器由测试直接调服务函数)。
import { randomUUID } from "node:crypto";
import type { TaskEngine } from "@umt/tasks";

export interface Enqueued {
  task: string;
  input: unknown;
  key: string;
}

/**
 * dedupe:同一幂等键只记一次并返回 deduplicated(贴近真实引擎);缺省每次都记,runId 为 run-1、run-2…
 */
export function fakeEngine(opts: { dedupe?: boolean } = {}): TaskEngine & { enqueued: Enqueued[] } {
  const enqueued: Enqueued[] = [];
  const keys = new Set<string>();
  let n = 0;
  return {
    enqueued,
    async enqueue(task, input, o) {
      if (opts.dedupe) {
        const dup = keys.has(o.idempotencyKey);
        if (!dup) {
          keys.add(o.idempotencyKey);
          enqueued.push({ task, input, key: o.idempotencyKey });
        }
        return { runId: randomUUID(), deduplicated: dup };
      }
      enqueued.push({ task, input, key: o.idempotencyKey });
      n++;
      return { runId: `run-${n}`, deduplicated: false };
    },
    async signal() {
      return { delivered: 0 };
    },
    async cancel() {
      return false;
    },
    async get() {
      return null;
    },
    async list() {
      return [];
    },
    async startWorker() {},
    async stop() {},
  };
}