/**
 * A mesh, raised from nothing, joined by two machines, delivering a credential neither the mesh
 * nor the broker can read.
 *
 * Everything before this proves a part. This proves the parts meet — which is the thing the
 * project keeps saying cannot be checked any other way (novox/hq ADR 0001: every fault of
 * 2026-08-22 was found in production because nothing could be stood up locally).
 *
 * It needs a host binary and the substrate bundle:
 *
 *   MESH_LAB_HOST_BINARY=.../mesh-host
 *   MESH_LAB_BUNDLE=.../examples/substrate-first-node.lock
 *
 * The bundle's image references are rewritten to the ones this scenario's own registry serves.
 * A digest belongs to whatever registry serves it, so a committed bundle names a registry that is
 * not this one — rewriting is what makes it applicable rather than a placeholder to tidy away.
 */

import { test, before, after } from "node:test";
import assert from "node:assert/strict";
import { existsSync, readFileSync } 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 } 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 substrate bundle (mesh-host examples/)"
      : false;

const SCENARIO = "two-nodes";
let instanceId = "";

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

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

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

/** The control plane, which runs in a container on the first node. */
async function mesh(command: string): Promise<string> {
  return must("anchor", `docker exec mesh-control /mesh-control ${command}`);
}

/**
 * The bundle, with every image reference pointed at this scenario's registry.
 *
 * Matched by repository rather than by the whole reference, because the address and the digest
 * both differ from whatever the committed bundle names — and a bundle that names the wrong
 * registry is not wrong, it is built for a different target.
 */
function bundleFor(images: string[]): string {
  let text = readFileSync(bundle, "utf8");
  for (const pinned of images) {
    const repository = pinned.slice(pinned.indexOf("/") + 1, pinned.indexOf("@"));
    const escaped = repository.replaceAll("/", "\\/").replaceAll(".", "\\.");
    text = text.replaceAll(
      new RegExp(`[A-Za-z0-9_.:-]+\\/${escaped}@sha256:[0-9a-f]+`, "g"),
      pinned,
    );
  }
  return text;
}

/** Take a token out of what `token issue` printed. It is the one base64url blob on its own line. */
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;
}

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

  // The first node raises everything from a file rather than from a bundle built into the binary,
  // because the digests are this registry's and are not known until it is up.
  await must("anchor", `cat > /tmp/substrate.lock <<'MESHBUNDLE'\n${bundleFor(raised.images)}\nMESHBUNDLE`);
  await must("anchor", `${HOST_PATH} apply /tmp/substrate.lock`);
}, { timeout: 1_800_000 });

after(async () => {
  if (instanceId) await destroy(instanceId);
  await destroyAll(`${SCENARIO}-`);
}, { timeout: 600_000 });

test("a bare machine becomes a mesh", { skip, timeout: 600_000 }, async () => {
  const running = await must("anchor", `docker ps --format '{{.Names}}'`);
  for (const container of ["mesh-store", "mesh-broker", "mesh-control"]) {
    assert.match(running, new RegExp(container), `${container} is not running`);
  }
  // Answering, not merely up. A container that is running is not a control plane that replies —
  // a distinction this project has already paid for once.
  assert.ok((await mesh("status")).length > 0);
});

test("both machines join it, and the token is all they need", { skip, timeout: 900_000 }, async () => {
  for (const [machine, node] of [["anchor", "anchor"], ["laptop", "laptop"]] as const) {
    await mesh(`node add ${node}`);
    const token = tokenFrom(await mesh(`token issue --node ${node}`));
    // No --name. The token says what the mesh calls the machine, which is the fault this walk
    // found the first time it was run.
    const said = await must(machine, `${HOST_PATH} enrol --token ${quote(token)}`);
    assert.match(said, new RegExp(`enrolled as ${node}`), said);
    assert.match(said, /sealing key/, "no sealing key was generated");
  }

  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.equal(recorded.trim().split("\n").map((l) => l.trim()).sort().join(","), "anchor,laptop",
    "the mesh did not record a sealing key for both machines");
});

test("a credential reaches both ends and the mesh holds neither", { skip, timeout: 900_000 }, async () => {
  // The whole argument, on real machines: the two ends must hold the SAME password, and it must
  // appear nowhere the mesh or the broker could read it.
  await must("anchor", `printf %s '{"module":"postgres","version":"1",` +
    `"provides":[{"name":"database","scope":"mesh"}],"serves":{"database":{"port":5432}},` +
    `"grants":{"database":"/var/lib/mesh-host/grants"},` +
    `"receives":{"database":"/var/lib/mesh-host/grants/mesh.json"},"resources":[]}' > /tmp/pg.json`);
  await must("anchor", `printf %s '{"module":"meshboard","version":"1",` +
    `"requires":["database"],"contributes":{"database":{"name":"meshboard"}},` +
    `"binds":{"database":"/etc/meshboard/database.json"},` +
    `"secrets":{"database":"/etc/meshboard/database.password"},"resources":[]}' > /tmp/app.json`);
  await must("anchor", `docker cp /tmp/pg.json mesh-control:/pg.json`);
  await must("anchor", `docker cp /tmp/app.json mesh-control:/app.json`);
  await mesh("module add /pg.json");
  await mesh("module add /app.json");

  await mesh("overlay place anchor --hub --endpoint 192.0.2.10:51820 --site lab");
  await mesh("overlay place laptop --site lab");
  for (const node of ["anchor", "laptop"]) await mesh(`assign ${node} networking`);
  await mesh("assign anchor postgres");
  await mesh("assign laptop meshboard");

  for (const machine of ["anchor", "laptop"]) {
    await must(machine, `nohup ${HOST_PATH} run > /var/log/mesh-host.log 2>&1 & sleep 3`);
  }
  await mesh("push");
  await new Promise((r) => setTimeout(r, 8000));

  const onConsumer = (await must("laptop", `cat /etc/meshboard/database.password`)).trim();
  const onProvider = (await must("anchor", `cat /var/lib/mesh-host/grants/laptop.secret`)).trim();
  assert.ok(onConsumer.length >= 40, `the consumer's credential is ${onConsumer.length} characters`);
  assert.equal(onConsumer, onProvider,
    "the two ends hold different passwords, so nothing could ever authenticate");

  // Only the machine it is for may read it.
  assert.match(await must("laptop", `stat -c %a /etc/meshboard/database.password`), /^600/);

  // And it is nowhere it could have been read on the way. The declaration crossed the broker; the
  // database is the control plane's; the state is what the node reported back.
  for (const [machine, where] of [
    ["laptop", "/var/lib/mesh-host/declared.json"],
    ["laptop", "/var/lib/mesh-host/state.json"],
    ["anchor", "/var/lib/mesh-host/declared.json"],
  ] as const) {
    const { out } = await on(machine, `grep -c ${quote(onConsumer)} ${where}`);
    assert.equal(out.trim(), "0", `the password is in ${where} on ${machine}`);
  }
  const inTheMesh = await must("anchor",
    `docker exec mesh-store psql -U postgres -d inventory -qAt ` +
      `-c "select count(*) from secret where for_consumer like '%${onConsumer}%' ` +
      `or for_provider like '%${onConsumer}%'"`);
  assert.equal(inTheMesh.trim(), "0", "the control plane's database holds the password in the clear");
});

test("the consumer is also told where its database is", { skip, timeout: 300_000 }, async () => {
  // A password with no address is not a connection. This is the readable half, which stays
  // readable on purpose — it is the secret half that could not be composed, not this one.
  const told = JSON.parse(await must("laptop", `cat /etc/meshboard/database.json`));
  assert.equal(told.from, "anchor");
  assert.equal(told.at, "anchor.internal");
  assert.equal(told.serves.port, 5432);
  // And the name it resolves to was written by the mesh as well, on this machine.
  assert.match(await must("laptop", `grep anchor.internal /etc/hosts`), /10\.42\.0\.\d+/);
});