/**
 * **Nothing a machine sends while the store restarts is lost** (novox/hq issues 082, 083).
 *
 * The foundation's store is recreated when it is adopted, and for those seconds the control plane
 * cannot write. This bed takes the store away on the control-node, has a second machine enrol into
 * the gap, and brings the store back after the control plane has had to say "not now":
 *
 *   - the enrolment completes on its own, with the keys it started with — the host asked again
 *     while the mesh said it could not answer, and the token was not spent until it could;
 *   - the control plane really did say "not now", so the gap was hit, not missed;
 *   - the machine then applies what it is pushed and is heard from.
 *
 * It needs a host binary and the foundation bundle:
 *
 *   MESH_LAB_HOST_BINARY=.../mesh-host
 *   MESH_LAB_BUNDLE=.../examples/foundation-first-node.lock
 */
import { test, before, after } from "node:test";
import assert from "node:assert/strict";
import { existsSync } from "node:fs";
import { loadScenario } from "../../src/declaration/parse.ts";
import { raise } from "../../src/lifecycle/raise.ts";
import { destroy, exec } from "../../src/lifecycle/operate.ts";
import { hostBinaryPath, HOST_PATH } from "../../src/lifecycle/place.ts";
import { labIsUsable, destroyAll, foundationBundle } from "./harness.ts";

const capability = await labIsUsable();
const binary = hostBinaryPath();
const bundle = process.env["MESH_LAB_BUNDLE"] ?? "";

const skip = !capability.usable
  ? `lab not usable: ${capability.why}`
  : !binary || !existsSync(binary)
    ? "MESH_LAB_HOST_BINARY is not set to a built mesh-host"
    : !bundle || !existsSync(bundle)
      ? "MESH_LAB_BUNDLE is not set to a foundation bundle (mesh-host examples/)"
      : false;

const SCENARIO = "store-window";
let instanceId = "";

function quote(s: string): string {
  return `'${s.replaceAll("'", `'\\''`)}'`;
}

async function on(machine: string, command: string, timeoutMs?: number): Promise<{ out: string; ok: boolean }> {
  const { stdout } = await exec(instanceId, machine, [
    "sh", "-c", `exec 2>&1\n${command}\necho "__exit=$?"`,
  ], timeoutMs);
  const marker = stdout.lastIndexOf("__exit=");
  if (marker < 0) return { out: stdout, ok: false };
  return { out: stdout.slice(0, marker), ok: stdout.slice(marker + 7).trim() === "0" };
}

async function must(machine: string, command: string, timeoutMs?: number): Promise<string> {
  const { out, ok } = await on(machine, command, timeoutMs);
  if (!ok) throw new Error(`${machine}: ${command}\n${out}`);
  return out;
}

async function mesh(command: string, timeoutMs?: number): Promise<string> {
  return must("anchor", `docker exec mesh-controller /mesh-controller ${command}`, timeoutMs);
}

function tokenFrom(said: string): string {
  const found = said.split("\n").map((l) => l.trim()).find((l) => l.length > 100 && !l.includes(" "));
  assert.ok(found, `no token in:\n${said}`);
  return found;
}

async function until(what: string, within: number, check: () => Promise<boolean>, why: () => Promise<string>): Promise<void> {
  const end = Date.now() + within;
  while (Date.now() < end) {
    if (await check()) return;
    await new Promise((r) => setTimeout(r, 3000));
  }
  assert.fail(`${what} did not happen within ${Math.round(within / 1000)}s:\n${await why()}`);
}

before(async () => {
  if (skip) return;
  const raised = await raise(loadScenario(`scenarios/${SCENARIO}.yml`), {
    onProgress: (m) => console.log(`raise: ${m}`),
  });
  instanceId = raised.instanceId;

  await must("anchor", `cat > /tmp/foundation.lock <<'MESHBUNDLE'\n${foundationBundle(bundle, raised.images)}\nMESHBUNDLE`);
  await must("anchor", `${HOST_PATH} apply /tmp/foundation.lock`, 600_000);
  const up = await must("anchor", `docker ps --format '{{.Names}}'`);
  for (const c of ["mesh-store", "mesh-broker", "mesh-controller"]) {
    assert.match(up, new RegExp(c), `the foundation did not raise ${c}:\n${up}`);
  }
  await mesh("node add anchor");
  const own = tokenFrom(await mesh("token issue --node anchor"));
  await must("anchor", `${HOST_PATH} enrol --token ${quote(own)}`);
  await must("anchor", `nohup ${HOST_PATH} run > /var/log/mesh-host.log 2>&1 & sleep 3`);
}, { timeout: 1_800_000 });

after(async () => {
  if (process.env["MESH_LAB_KEEP"]) { console.log(`MESH_LAB_KEEP set — leaving ${instanceId} standing`); return; }
  if (instanceId) await destroy(instanceId);
  await destroyAll(`${SCENARIO}-`);
}, { timeout: 600_000 });

test("a machine enrolling while the store is away joins when it comes back, with the keys it started with", {
  skip, timeout: 900_000,
}, async () => {
  await mesh("node add laptop");
  const token = tokenFrom(await mesh("token issue --node laptop"));

  // The store goes away, as it does when the foundation is adopted; the broker stays, so the
  // enrolment reaches the control plane and the control plane cannot write.
  await must("anchor", `docker stop mesh-store`);

  // The machine enrols into the gap. In the background: it will be told "not now" and keep asking.
  await must("laptop", `nohup sh -c ${quote(`${HOST_PATH} enrol --token ${quote(token)} > /tmp/enrol.log 2>&1; ` +
    `echo "exit=$?" >> /tmp/enrol.log`)} > /dev/null 2>&1 & sleep 1`);

  // The control plane said "not now" at least once — so the gap was hit, not missed.
  await until("the control plane asking the machine to enrol again", 90_000,
    async () => /asked "laptop" to enrol again/.test((await on("anchor", `docker logs mesh-controller 2>&1`)).out),
    async () => `--- controller ---\n${(await on("anchor", `docker logs --tail 30 mesh-controller 2>&1`)).out}\n` +
      `--- laptop enrol ---\n${(await on("laptop", `cat /tmp/enrol.log`)).out}`);

  // The store comes back; the enrolment completes on its own, with nothing done by hand.
  await must("anchor", `docker start mesh-store`);
  await until("the enrolment completing", 150_000,
    async () => /exit=/.test((await on("laptop", `cat /tmp/enrol.log`)).out),
    async () => `--- laptop enrol ---\n${(await on("laptop", `cat /tmp/enrol.log`)).out}\n` +
      `--- controller ---\n${(await on("anchor", `docker logs --tail 30 mesh-controller 2>&1`)).out}`);
  const said = (await on("laptop", `cat /tmp/enrol.log`)).out;
  assert.match(said, /exit=0/, `the enrolment did not complete after the store came back:\n${said}`);
  assert.match(said, /enrolled as laptop/, `the machine was not enrolled as laptop:\n${said}`);

  // Enrolled with the keys it generated at the start — one attempt, not a new identity — and the
  // mesh holds its sealing key, which it recorded only once the store was back.
  const generated = said.match(/generated this node's identity: (\S+)/);
  assert.ok(generated, `the enrolment did not say which identity it generated:\n${said}`);
  assert.equal((said.match(/generated this node's identity:/g) ?? []).length, 1,
    `the machine generated more than one identity:\n${said}`);
  const recorded = await must("anchor",
    `docker exec mesh-store psql -U postgres -d inventory -qAt ` +
      `-c "select name from node where sealing_key is not null order by name"`);
  assert.match(recorded, /(^|\n)laptop(\n|$)/, `the mesh holds no sealing key for laptop:\n${recorded}`);

  // And the machine is a working member: pushed something, it applies it and is heard from.
  await must("laptop", `nohup ${HOST_PATH} run > /var/log/mesh-host.log 2>&1 & sleep 3`);
  await must("anchor", `printf %s '{"module":"marker","version":"1","resources":[` +
    `{"id":"marker","type":"file","path":"/etc/store-window","content":"joined\\\\n","mode":"0644"}]}' > /tmp/marker.json`);
  await must("anchor", `docker cp /tmp/marker.json mesh-controller:/marker.json`);
  await mesh("module add /marker.json");
  await mesh("assign laptop marker");
  await mesh("push laptop");
  await until("the machine applying what it was pushed", 120_000,
    async () => (await on("laptop", `grep -q joined /etc/store-window`)).ok,
    async () => (await on("laptop", `tail -20 /var/log/mesh-host.log`)).out);
  await until("the mesh hearing the machine's report", 120_000,
    async () => {
      const r = await on("anchor", `docker exec mesh-controller /mesh-controller status --json`);
      if (!r.ok) return false;
      const state = JSON.parse(r.out) as { reported: { node: string; outcome: string; current: boolean }[] };
      return state.reported.some((w) => w.node === "laptop" && w.outcome === "applied" && w.current);
    },
    async () => (await on("anchor", `docker exec mesh-controller /mesh-controller status 2>&1`)).out);
});