import test from "node:test";
import assert from "node:assert/strict";
import { PassThrough } from "node:stream";
import { mkdtemp, writeFile, rm } from "node:fs/promises";
import { tmpdir } from "node:os";
import { join } from "node:path";
import { fileURLToPath } from "node:url";
import { serveRestrictedRegistry, RestrictedEngineBudget } from "./service.mjs";

const workerd = process.env.QUIXOS_TEST_WORKERD;
if (!workerd) throw Error("Set QUIXOS_TEST_WORKERD to the pinned engine");
const worker = fileURLToPath(new URL("./worker.mjs", import.meta.url));
const abi = "quixos-transaction-ports-v1";
let next = 0;
async function fixture(source, options = {}) {
  const directory = await mkdtemp(join(tmpdir(), "qx-restricted-test-"));
  const module = join(directory, "module.mjs");
  await writeFile(module, source);
  const io = { stdin: new PassThrough(), stdout: new PassThrough(), exitCode: 0 };
  const waiting = [],
    queued = [];
  const usage = [];
  let buffer = "";
  io.stdout.on("data", (chunk) => {
    buffer += chunk;
    let index;
    while ((index = buffer.indexOf("\n")) >= 0) {
      const value = JSON.parse(buffer.slice(0, index));
      buffer = buffer.slice(index + 1);
      if (value.kind === "usage") {
        usage.push(value);
        continue;
      }
      if (waiting.length) waiting.shift()(value);
      else queued.push(value);
    }
  });
  const receive = async () => {
    if (queued.length) return queued.shift();
    let timer;
    try {
      return await Promise.race([
        new Promise((resolve) => waiting.push(resolve)),
        new Promise((_, reject) => {
          timer = setTimeout(() => reject(Error("TEST_MESSAGE_TIMEOUT")), 5000);
        }),
      ]);
    } finally {
      clearTimeout(timer);
    }
  };
  const service = await serveRestrictedRegistry(
    {
      workerd,
      worker,
      module,
      sandbox: process.env.QUIXOS_TEST_SANDBOX,
      registryExport: "registry",
      exports: ["test"],
      sdk: [],
      ...options,
    },
    io,
  );
  assert.deepEqual(await receive(), { abi, kind: "ready", exports: ["test"] });
  const send = (value) => io.stdin.write(JSON.stringify({ abi, ...value }) + "\n");
  const start = (input = null, budget) => {
    const invocation = "invoke-" + ++next,
      frame = "frame-" + next;
    send({
      kind: "invoke",
      invocation,
      frame,
      exportId: "test",
      workspace: "workspace:restricted",
      receiver: null,
      input,
      effect: "snapshot",
      ...(budget ? { budget } : {}),
    });
    return { invocation, frame };
  };
  return {
    io,
    receive,
    send,
    start,
    usage,
    stats: service.stats,
    async close() {
      await service.close();
      await rm(directory, { recursive: true, force: true });
    },
  };
}
const registry = (code) => `export const registry={exports:['test'],async invoke(request,channel){${code}}};`;

test("uncertain OS cleanup cannot release engine capacity", async () => {
  const budget = new RestrictedEngineBudget(1, async () => ({
    async release() {
      throw Error("kernel cleanup not confirmed");
    },
  }));
  const release = await budget.acquire(
    () => false,
    async () => {},
  );
  await assert.rejects(release(), /cleanup not confirmed/);
  assert.equal(budget.stats().engines, 1);
  await assert.rejects(
    budget.acquire(
      () => false,
      async () => {},
    ),
    { code: "RESTRICTED_ENGINE_LIMIT" },
  );
});

test("parallel frames route independently and cancellation cannot retire a neighbor", async () => {
  const f = await fixture(
    registry("return await channel({portId:'read',action:{kind:'state',primitive:'read'},input:request.input});"),
  );
  try {
    const first = f.start("a"),
      second = f.start("b");
    const ports = new Map([await f.receive(), await f.receive()].map((port) => [port.invocation, port]));
    assert.equal(ports.get(first.invocation).input, "a");
    assert.equal(ports.get(second.invocation).input, "b");
    f.send({ kind: "cancel", ...first });
    assert.equal((await f.receive()).kind, "cancelled");
    f.send({
      kind: "port-result",
      ...first,
      sequence: ports.get(first.invocation).sequence,
      status: "returned",
      output: "late",
    });
    f.send({
      kind: "port-result",
      ...second,
      sequence: ports.get(second.invocation).sequence,
      status: "returned",
      output: "survived",
    });
    const result = await f.receive();
    assert.equal(result.invocation, second.invocation);
    assert.equal(result.output, "survived");
    assert.equal(f.io.exitCode, 0);
  } finally {
    await f.close();
  }
});

test("A to B to A uses reserved nested capacity while both root lanes are saturated", async () => {
  const source = registry(
    "if(request.input==='leaf')return 'done'; return await channel({portId:'next',action:{kind:'state',primitive:'read'},input:request.input});",
  );
  const a = await fixture(source, { maxActive: 1, maxNested: 1, maxQueued: 1 });
  const b = await fixture(source, { maxActive: 1, maxNested: 1, maxQueued: 1 });
  const budget = (depth) => ({ root: "root-chain", depth, deadlineMs: 2000, calls: 20 });
  try {
    const parent = a.start("B", budget(1)),
      aPort = await a.receive();
    const neighbor = b.start("held", { ...budget(1), root: "other-root" });
    await b.receive();
    const child = b.start("A", budget(2)),
      bPort = await b.receive();
    const leaf = a.start("leaf", budget(3));
    const leafResult = await a.receive();
    assert.equal(leafResult.invocation, leaf.invocation);
    assert.equal(leafResult.output, "done");
    b.send({ kind: "port-result", ...child, sequence: bPort.sequence, status: "returned", output: leafResult.output });
    const childResult = await b.receive();
    a.send({
      kind: "port-result",
      ...parent,
      sequence: aPort.sequence,
      status: "returned",
      output: childResult.output,
    });
    assert.equal((await a.receive()).output, "done");
    b.send({ kind: "cancel", ...neighbor });
    assert.equal((await b.receive()).kind, "cancelled");
  } finally {
    await a.close();
    await b.close();
  }
});

test("the remaining root wall budget overrides a longer adapter deadline", async () => {
  const f = await fixture(
    registry("return await channel({portId:'held',action:{kind:'state',primitive:'read'},input:null});"),
    { deadlineMs: 2000 },
  );
  try {
    const started = performance.now();
    f.start(null, { root: "short-root", depth: 2, deadlineMs: 150, calls: 10 });
    await f.receive();
    const result = await f.receive();
    assert.equal(result.error.code, "RESTRICTED_DEADLINE");
    assert.ok(performance.now() - started < 1000);
  } finally {
    await f.close();
  }
});

test("real engine returns results and resets all globals between frames", async () => {
  const f = await fixture(
    registry(
      "globalThis.retained=(globalThis.retained??0)+1; return {count:globalThis.retained,text:new Intl.Segmenter('zh',{granularity:'word'}).segment('雨后的书店').containing(3).segment};",
    ),
  );
  try {
    for (let n = 0; n < 3; n++) {
      const call = f.start();
      const result = await f.receive();
      assert.equal(result.invocation, call.invocation);
      assert.equal(result.status, "returned");
      assert.equal(result.output.count, 1);
      assert.equal(typeof result.output.text, "string");
    }
  } finally {
    await f.close();
  }
});
test("captured frame is the sole source of nested port identities", async () => {
  const f = await fixture(
    registry("return await channel({portId:'read',action:{kind:'state',primitive:'read'},input:null});"),
  );
  try {
    const call = f.start();
    const port = await f.receive();
    assert.equal(port.kind, "port");
    assert.equal(port.frame, call.frame);
    assert.equal(port.invocation, call.invocation);
    f.send({ kind: "port-result", ...call, sequence: port.sequence, status: "returned", output: 42 });
    const result = await f.receive();
    assert.equal(result.status, "returned");
    assert.equal(result.output, 42);
  } finally {
    await f.close();
  }
});
test("authored serialization cannot forge result routing or ABI fields", async () => {
  const f = await fixture(
    registry(
      "Object.prototype.toJSON=function(){return this.status==='returned'?{status:'returned',output:42,invocation:'forged',abi:'forged'}:this;};return 42;",
    ),
  );
  try {
    const call = f.start();
    const result = await f.receive();
    assert.equal(result.invocation, call.invocation);
    assert.equal(result.abi, abi);
    assert.equal(result.status, "failed");
    assert.equal(result.error.code, "RESTRICTED_PACKAGE_FAILED");
  } finally {
    await f.close();
  }
});
test("the checked portable SDK keeps codecs and nested graph ports inside the frame", async () => {
  const sdk = process.env.QUIXOS_TEST_SDK;
  assert.ok(sdk, "Set QUIXOS_TEST_SDK to the checked portable SDK");
  const C = await import(sdk),
    workspace = C.workspaceId("workspace:restricted");
  const integer = { kind: "scalar", name: "int64" },
    unit = { kind: "builtin", name: "unit" };
  const declarations = [
    {
      id: "test",
      name: "test",
      effect: "snapshot",
      receiver: null,
      input: integer,
      output: integer,
      methods: [
        {
          name: "get",
          portName: "count",
          portId: "count-read",
          action: { kind: "state", primitive: "read" },
          input: unit,
          output: integer,
          keyed: false,
        },
      ],
    },
  ];
  const source = `import {definePortableRegistry} from 'qx:core'; export const registry=definePortableRegistry(${JSON.stringify(declarations)},{test:async ctx=>ctx.input+await ctx.ports.count.get()});`;
  const f = await fixture(source, { sdk: [{ name: "qx:core", path: sdk }] });
  try {
    const call = f.start(C.encodeArgument(integer, 2n, { workspace }));
    const port = await f.receive();
    assert.equal(port.kind, "port");
    assert.equal(C.decodeArgument(unit, port.input, { workspace }), null);
    f.send({
      kind: "port-result",
      ...call,
      sequence: port.sequence,
      status: "returned",
      output: C.encodeArgument(integer, 4n, { workspace }),
    });
    const result = await f.receive();
    assert.equal(result.status, "returned");
    assert.equal(C.decodeArgument(integer, result.output, { workspace }), 6n);
  } finally {
    await f.close();
  }
});
test("ambient clock, entropy, network and native imports are denied", async () => {
  for (const code of [
    "Date.now()",
    "new Date()",
    "new Intl.DateTimeFormat().format()",
    "new Intl.DateTimeFormat().formatToParts()",
    "Math.random()",
    "crypto.randomUUID()",
    "fetch('https://example.com')",
    "(await import('node:fs')).readFileSync('/etc/passwd')",
    "(await import('./unlisted.mjs')).secret",
  ]) {
    const f = await fixture(registry(`return ${code};`));
    try {
      f.start();
      assert.equal((await f.receive()).status, "failed", code);
    } finally {
      await f.close();
    }
  }
});
test("explicit dates remain useful without an implicit clock", async () => {
  const f = await fixture(registry("return new Date('2026-01-01T00:00:00Z').toISOString();"));
  try {
    f.start();
    assert.equal((await f.receive()).output, "2026-01-01T00:00:00.000Z");
  } finally {
    await f.close();
  }
});
test("initialization and regex loops are killed, then a fresh frame can start", async () => {
  for (const source of [
    "while(true){};" + registry("return 1;"),
    registry("return /(a+)+$/.test('a'.repeat(100000)+'!');"),
  ]) {
    const f = await fixture(source, { deadlineMs: 350 });
    try {
      for (let n = 0; n < 2; n++) {
        f.start();
        const result = await f.receive();
        assert.equal(result.error.code, "RESTRICTED_DEADLINE");
        assert.ok(
          f.usage.some((value) => value.cpuMicroseconds >= 50000),
          "External watchdog did not account spinning engine CPU",
        );
      }
    } finally {
      await f.close();
    }
  }
});
test("cancellation kills the entire frame before acknowledgment and rejects late port replies", async () => {
  const f = await fixture(
    registry("return await channel({portId:'read',action:{kind:'state',primitive:'read'},input:null});"),
  );
  try {
    const call = f.start();
    const port = await f.receive();
    f.send({ kind: "cancel", ...call });
    const cancelled = await f.receive();
    assert.equal(cancelled.kind, "cancelled");
    f.send({ kind: "port-result", ...call, sequence: port.sequence, status: "returned", output: "late" });
    const next = f.start();
    const nextPort = await f.receive();
    assert.equal(nextPort.invocation, next.invocation);
    f.send({ kind: "port-result", ...next, sequence: nextPort.sequence, status: "returned", output: "fresh" });
    const result = await f.receive();
    assert.equal(result.output, "fresh");
    assert.equal(result.invocation, next.invocation);
  } finally {
    await f.close();
  }
});
test("cancellation during asynchronous preparation leaves no running frame", async () => {
  const f = await fixture(registry("return 1;"));
  try {
    for (let n = 0; n < 5; n++) {
      const call = f.start();
      f.send({ kind: "cancel", ...call });
      assert.equal((await f.receive()).kind, "cancelled");
    }
    f.start();
    assert.equal((await f.receive()).output, 1);
  } finally {
    await f.close();
  }
});

test("bounded FIFO rejects overload without losing active or queued frames", async () => {
  const f = await fixture(
    registry("return await channel({portId:'read',action:{kind:'state',primitive:'read'},input:request.input});"),
    { maxQueued: 2, maxActive: 1 },
  );
  try {
    const first = f.start(1),
      port = await f.receive();
    const second = f.start(2),
      third = f.start(3),
      overflow = f.start(4);
    const refused = await f.receive();
    assert.equal(refused.invocation, overflow.invocation);
    assert.equal(refused.error.code, "RESTRICTED_QUEUE_FULL");
    f.send({ kind: "cancel", ...second });
    assert.equal((await f.receive()).invocation, second.invocation);
    f.send({ kind: "port-result", ...first, sequence: port.sequence, status: "returned", output: 1 });
    assert.equal((await f.receive()).output, 1);
    const nextPort = await f.receive();
    assert.equal(nextPort.invocation, third.invocation);
    assert.equal(nextPort.input, 3);
    f.send({ kind: "port-result", ...third, sequence: nextPort.sequence, status: "returned", output: 3 });
    assert.equal((await f.receive()).output, 3);
    f.start(5);
    const fresh = await f.receive();
    f.send({
      kind: "port-result",
      invocation: fresh.invocation,
      frame: fresh.frame,
      sequence: fresh.sequence,
      status: "returned",
      output: 5,
    });
    assert.equal((await f.receive()).output, 5);
  } finally {
    await f.close();
  }
});

test("queue wait consumes the deadline and cancelled work never reaches its ports", async () => {
  const f = await fixture(
    registry("return await channel({portId:'read',action:{kind:'state',primitive:'read'},input:null});"),
    { deadlineMs: 4000, maxActive: 1 },
  );
  try {
    const first = f.start();
    assert.equal((await f.receive()).kind, "port");
    // Expire while the first call is deliberately blocked. Two equal relative
    // deadlines let fast startup legitimately begin the queued call first.
    const queued = f.start(null, { root: "queued-deadline", deadlineMs: 50, depth: 1, calls: 10 });
    const expired = await f.receive();
    assert.equal(expired.invocation, queued.invocation);
    assert.equal(expired.error.code, "RESTRICTED_DEADLINE");
    f.send({ kind: "cancel", ...first });
    const cancelled = await f.receive();
    assert.equal(cancelled.invocation, first.invocation);
    assert.equal(cancelled.kind, "cancelled");
    const fresh = f.start();
    const port = await f.receive();
    assert.equal(port.invocation, fresh.invocation);
    f.send({ kind: "port-result", ...fresh, sequence: port.sequence, status: "returned", output: "fresh" });
    assert.equal((await f.receive()).output, "fresh");
  } finally {
    await f.close();
  }
});

test("warm engines create fresh transitive module state, closures and built-ins", async () => {
  const directory = await mkdtemp(join(tmpdir(), "qx-transitive-"));
  const helper = join(directory, "helper.mjs");
  await writeFile(
    helper,
    "let value=0, retained; export function touch(channel){const old=retained; retained=channel; return {count:++value, captured:!!old};}",
  );
  const f = await fixture(
    `import {touch} from 'helper.mjs'; let count=0;
    export const registry={exports:['test'],async invoke(request,channel){
      const before={object:Object.prototype.retained??null,array:Array.prototype.retained??null,
        map:Map.prototype.retained??null, global:globalThis.retained??null};
      Object.prototype.retained=request.input; Array.prototype.retained=request.input;
      Map.prototype.retained=request.input; globalThis.retained=request.input;
      return {count:++count, helper:touch(channel), before};
    }};`,
    { sdk: [{ name: "helper.mjs", path: helper }] },
  );
  try {
    for (const value of ["private graph A", "private graph B", "private graph C"]) {
      f.start(value);
      assert.deepEqual((await f.receive()).output, {
        count: 1,
        helper: { count: 1, captured: false },
        before: { object: null, array: null, map: null, global: null },
      });
    }
    assert.equal(f.stats().starts, 1, "Qualification must exercise actual engine reuse");
    assert.equal(f.stats().reused, 2);
    assert.equal(f.stats().idle, 1);
  } finally {
    await f.close();
    await rm(directory, { recursive: true, force: true });
  }
});

test("an expired frame token cannot borrow a later invocation's broker", async () => {
  const directory = await mkdtemp(join(tmpdir(), "qx-token-"));
  const worker = join(directory, "token-test.mjs");
  // Trusted test entrypoint deliberately replays the old token. Authored
  // registries never receive CONFIG or BROKER directly.
  await writeFile(
    worker,
    `export default {async fetch(request,env) {
    const message=await request.json();
    const output=message.input ? (await env.BROKER.fetch('http://frame/port/'+message.input,{
      method:'POST',body:JSON.stringify({portId:'read',action:{kind:'state',primitive:'read'},input:null})})).status
      : env.CONFIG.frameToken;
    return Response.json({status:'returned',output});
  }};`,
  );
  const f = await fixture(registry("return null;"), { worker });
  try {
    f.start();
    const token = (await f.receive()).output;
    assert.match(token, /^[a-f0-9-]{36}$/);
    f.start(token);
    assert.equal((await f.receive()).output, 409);
    assert.equal(f.stats().starts, 1);
    assert.equal(f.stats().reused, 1);
  } finally {
    await f.close();
    await rm(directory, { recursive: true, force: true });
  }
});

test("idle engines evict without a graph poll and restart with fresh state", async () => {
  const f = await fixture(registry("return request.input;"), { engineIdleMs: 30 });
  try {
    f.start("first");
    assert.equal((await f.receive()).output, "first");
    await new Promise((resolve) => setTimeout(resolve, 100));
    assert.equal(f.stats().engines, 0);
    f.start("second");
    assert.equal((await f.receive()).output, "second");
    assert.equal(f.stats().starts, 2);
  } finally {
    await f.close();
  }
});

for (const loop of [
  "while(true) await Promise.resolve();",
  "const memory=[]; for(let n=0;n<128;n++) memory.push(new Uint8Array(256*1024)); while(true) await Promise.resolve(memory);",
])
  test("await/allocation pressure is fenced without delaying a neighboring engine: " + loop.slice(0, 28), async () => {
    const f = await fixture(registry(`if(request.input==='spin'){${loop}} return request.input;`), {
      deadlineMs: 1500,
    });
    try {
      const stuck = f.start("spin", { root: "stuck", depth: 1, deadlineMs: 350, calls: 10 });
      const before = performance.now();
      const healthy = f.start("healthy");
      const replies = [await f.receive(), await f.receive()];
      assert.equal(replies.find((r) => r.invocation === healthy.invocation).output, "healthy");
      assert.equal(replies.find((r) => r.invocation === stuck.invocation).error.code, "RESTRICTED_DEADLINE");
      assert.equal(replies[0].invocation, healthy.invocation, "Healthy work must finish before the stuck deadline");
      assert.ok(performance.now() - before < 1200);
      f.start("after fault");
      assert.equal((await f.receive()).output, "after fault");
      assert.equal(f.stats().starts, 2, "The healthy engine survives its neighbor's termination");
    } finally {
      await f.close();
    }
  });

test("detached microtask loops cannot escape the invocation wall deadline", async () => {
  const f = await fixture(
    registry("void(async()=>{while(true)await Promise.resolve();})(); return 'nominal return';"),
    { deadlineMs: 200 },
  );
  try {
    const before = performance.now();
    f.start();
    assert.equal((await f.receive()).error.code, "RESTRICTED_DEADLINE");
    assert.ok(performance.now() - before < 1000);
    assert.equal(f.stats().engines, 0);
  } finally {
    await f.close();
  }
});

test("detached digest callbacks cannot use a completed frame or contaminate reuse", async () => {
  const f = await fixture(
    registry(`
    void(async()=>{
      for(let n=0;n<100;n++)await crypto.subtle.digest('SHA-256',new Uint8Array(32768));
      await channel({portId:'late',action:{kind:'state',primitive:'read'},input:request.input});
    })().catch(()=>{});
    return request.input;
  `),
  );
  try {
    f.start("private A");
    assert.equal((await f.receive()).output, "private A");
    await new Promise((resolve) => setTimeout(resolve, 75));
    f.start("private B");
    const reply = await f.receive();
    assert.equal(reply.status, "returned", "No late graph port may appear after completion");
    assert.equal(reply.output, "private B");
    assert.equal(f.stats().starts, 1);
  } finally {
    await f.close();
  }
});

test("the shared engine budget evicts idle code families and rejects busy oversubscription", async () => {
  const engineBudget = new RestrictedEngineBudget(1);
  const a = await fixture(registry("return request.input;"), { engineBudget });
  const b = await fixture(
    registry("return await channel({portId:'read',action:{kind:'state',primitive:'read'},input:null});"),
    { engineBudget },
  );
  try {
    a.start("first family");
    assert.equal((await a.receive()).output, "first family");
    const busy = b.start();
    const port = await b.receive();
    assert.equal(a.stats().engines, 0, "Idle foreign code is evicted before allocating another engine");
    assert.equal(engineBudget.stats().engines, 1);
    a.start("overload");
    assert.equal((await a.receive()).error.code, "RESTRICTED_ENGINE_LIMIT");
    assert.equal(engineBudget.stats().engines, 1);
    b.send({ kind: "port-result", ...busy, sequence: port.sequence, status: "returned", output: "survived" });
    assert.equal((await b.receive()).output, "survived");
  } finally {
    await Promise.all([a.close(), b.close()]);
  }
  assert.equal(engineBudget.stats().engines, 0);
});