/**
 * @file Tests for `server/lib/clone-queue.js`: no more clones run at once
 * than the limit, the rest start in arrival order as slots free, a failing
 * clone frees its slot too, the per-clone thread share, and a tracked
 * clone's progress: its queue position, git's --progress lines parsed, and
 * shown only to its owner.
 * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
 */

const { describe, it, afterEach } = require("node:test");
const assert = require("node:assert/strict");
const os = require("node:os");

const queue = require("../lib/clone-queue");

const saved = process.env.AGENTHUB_CLONE_CONCURRENCY;

function gate() {
  let open;
  const p = new Promise((r) => (open = r));
  return { p, open };
}

describe("clone-queue", () => {
  afterEach(() => {
    if (saved === undefined) delete process.env.AGENTHUB_CLONE_CONCURRENCY;
    else process.env.AGENTHUB_CLONE_CONCURRENCY = saved;
  });

  it("runs at most the limit at once, the rest in arrival order", async () => {
    process.env.AGENTHUB_CLONE_CONCURRENCY = "2";
    const started = [];
    const gates = [gate(), gate(), gate(), gate()];
    const runs = gates.map((g, i) =>
      queue.withCloneSlot(async () => {
        started.push(i);
        await g.p;
        return i;
      })
    );
    await new Promise((r) => setImmediate(r));
    assert.deepEqual(started, [0, 1]);
    assert.deepEqual(queue.cloneQueueState(), { running: 2, waiting: 2, limit: 2 });
    gates[1].open();
    await runs[1];
    await new Promise((r) => setImmediate(r));
    assert.deepEqual(started, [0, 1, 2]);
    gates[0].open();
    gates[2].open();
    gates[3].open();
    assert.deepEqual(await Promise.all(runs), [0, 1, 2, 3]);
    assert.deepEqual(queue.cloneQueueState(), { running: 0, waiting: 0, limit: 2 });
  });

  it("frees the slot when a clone fails", async () => {
    process.env.AGENTHUB_CLONE_CONCURRENCY = "1";
    await assert.rejects(
      queue.withCloneSlot(async () => {
        throw new Error("boom");
      }),
      /boom/
    );
    assert.equal(await queue.withCloneSlot(async () => "ok"), "ok");
    assert.equal(queue.cloneQueueState().running, 0);
  });

  it("splits the cores between the running clones", () => {
    const cores = os.availableParallelism?.() ?? os.cpus().length;
    process.env.AGENTHUB_CLONE_CONCURRENCY = "1";
    assert.equal(queue.threads(), Math.max(1, cores));
    process.env.AGENTHUB_CLONE_CONCURRENCY = String(cores * 4);
    assert.equal(queue.threads(), 1);
    delete process.env.AGENTHUB_CLONE_CONCURRENCY;
    assert.equal(queue.concurrency(), Math.max(1, Math.floor(cores / 2)));
  });

  it("reports a tracked clone's queue position, then git's progress, to its owner only", async () => {
    process.env.AGENTHUB_CLONE_CONCURRENCY = "1";
    const first = gate();
    const a = queue.track("tok-aaaaaaaaaaaaaaaa", 7);
    const b = queue.track("tok-bbbbbbbbbbbbbbbb", 7);
    const ra = queue.withCloneSlot(() => first.p, a);
    let release;
    const rb = queue.withCloneSlot(() => new Promise((r) => (release = r)), b);
    await new Promise((r) => setImmediate(r));
    assert.equal(queue.progress("tok-aaaaaaaaaaaaaaaa", 7).state, "running");
    const waitingView = queue.progress("tok-bbbbbbbbbbbbbbbb", 7);
    assert.equal(waitingView.state, "queued");
    assert.equal(waitingView.position, 1);
    assert.equal(waitingView.running, 1);
    // Another user — or nobody — never sees it.
    assert.equal(queue.progress("tok-bbbbbbbbbbbbbbbb", 8), null);
    assert.equal(queue.progress("tok-cccccccccccccccc", 7), null);

    queue.report(
      a,
      "Cloning into 'r'...\nremote: Counting objects: 100% (5/5), done.\n" +
        "Receiving objects:  12% (120/1000), 3.00 MiB | 1.50 MiB/s\rReceiving objects:  45% (450/1000), 120.50 MiB | 5.20 MiB/s"
    );
    const v = queue.progress("tok-aaaaaaaaaaaaaaaa", 7);
    assert.equal(v.phase, "receiving");
    assert.equal(v.percent, 45);
    assert.equal(v.detail, "450/1000, 120.50 MiB | 5.20 MiB/s");
    queue.report(a, "Resolving deltas: 100% (300/300), done.\n");
    assert.equal(queue.progress("tok-aaaaaaaaaaaaaaaa", 7).phase, "resolving");
    assert.equal(queue.progress("tok-aaaaaaaaaaaaaaaa", 7).detail, "300/300");

    first.open();
    await ra;
    queue.finish(a, true);
    assert.equal(queue.progress("tok-aaaaaaaaaaaaaaaa", 7).state, "done");
    await new Promise((r) => setImmediate(r));
    assert.equal(queue.progress("tok-bbbbbbbbbbbbbbbb", 7).state, "running");
    release();
    await rb;
    queue.finish(b, false);
    assert.equal(queue.progress("tok-bbbbbbbbbbbbbbbb", 7).state, "failed");
  });

  it("refuses a malformed or reused token, and keeps progress out of an error", () => {
    assert.throws(() => queue.track("short", null), { code: "EBADFIELD" });
    assert.throws(() => queue.track("../../etc/passwd-xxxxxxxx", null), { code: "EBADFIELD" });
    queue.track("tok-dddddddddddddddd", null);
    assert.throws(() => queue.track("tok-dddddddddddddddd", null), { code: "EBADFIELD" });
    assert.equal(
      queue.stripProgress(
        "Cloning into 'r'...\nReceiving objects:  45% (450/1000)\rfatal: early EOF\n"
      ),
      "Cloning into 'r'...\nfatal: early EOF"
    );
  });
});