/**
 * FOUR FRESH MACHINES, AND NOTHING HANDED TO THEM.
 *
 * The four-machine bed (`whole-mesh-full`) proves the mesh converges. It does so by loading
 * thirty-four of the mesh's own images onto its machines from the workstation, because it does not
 * build them — something beside the bed built them and copied them in. No real installation looks
 * like that, and the lab has been burned by exactly this shape before: it used to raise a registry
 * inside the scenario, and a bootstrap that only worked against that registry went green here and
 * would have failed on any bare machine.
 *
 * This bed hands over nothing. The scenario has no `images:` list at all. What the machines get is
 * a container runtime and the host binary — prerequisites of a machine, not parts of a mesh — and
 * from there:
 *
 *   1. novox is raised into a mesh of one by the installer, which BUILDS the control plane.
 *   2. ace, shanks and g14 JOIN it, across a household NAT, with a token and nothing else.
 *   3. The mesh builds the shared base from source, with its own builder.
 *   4. The mesh builds a real module standing on that base.
 *   5. The anchor runs it, pinned to a digest the mesh's own registry assigned.
 *   6. A JOINED machine runs it — which means pulling from a registry that asks who it is.
 *
 * Steps 1 and 2 are proven elsewhere and are here because the later ones need them. **Steps 3
 * through 6 are what this bed exists for**, and 6 is the one nothing has ever checked: genesis
 * puts the builder, the registry and everything they produce on ONE machine, so every earlier
 * proof of a mesh-built module running is a proof about the machine that built it. A second
 * machine has to fetch, and fetching needs an account nothing yet grants (novox/hq issue 042).
 *
 * Each step is recorded separately rather than allowed to throw, so a gap at 6 reports as a gap at
 * 6 instead of erasing the evidence for 3, 4 and 5.
 *
 *   MESH_LAB_INCUS='sudo -n incus'
 *   MESH_LAB_HOST_BINARY=.../mesh-host/mesh-host
 *   MESH_LAB_BOOTSTRAP_BINARY=.../mesh-host/mesh-bootstrap
 *   MESH_LAB_BUNDLE=.../mesh-host/examples/substrate-first-node.lock
 *   MESH_LAB_CATALOG=.../mesh-catalog/modules
 *   MESH_LAB_SOURCE=<forge>/mesh-control.git   MESH_LAB_SOURCE_REF=<commit>
 *   MESH_LAB_KEEP=1   to leave it standing afterwards
 */
import { test, before, after } from "node:test";
import assert from "node:assert/strict";
import { existsSync } from "node:fs";
import { resolve } from "node:path";
import { loadScenario } from "../../src/declaration/parse.ts";
import { raise } from "../../src/lifecycle/raise.ts";
import { destroy, exec, push } from "../../src/lifecycle/operate.ts";
import { bootstrapBinaryPath, hostBinaryPath, HOST_PATH } from "../../src/lifecycle/place.ts";
import { labIsUsable, destroyAll, substrateBundle } from "./harness.ts";
import { genesis, type GenesisResult } from "./genesis.ts";

const SCENARIO = "fresh-mesh";
const CONTROL = "novox";
const HOME_NODES = ["ace", "shanks", "g14"];
/** The joined machine asked to run a mesh-built module. Any of the three would do. */
const SECOND = "ace";

/** The anchor's public address — what every other machine dials, and what its own token must name. */
const ANCHOR = "192.0.2.20";
/** Where this mesh's registry answers, on the anchor's public address so a joined node can reach it. */
const REGISTRY = `${ANCHOR}:5000`;

/**
 * The module built on top of the base, and the base it stands on.
 *
 * `amqp-ping` is deliberately small and deliberately REAL: its own TypeScript, compiled by the
 * shared toolchain, running on the shared runtime, talking to the broker. A module whose artifact
 * is a mirrored public image would pass every assertion below while skipping the whole of what is
 * under test (novox/hq SELF-UPGRADE-PLAN, rule 1).
 */
const BASE = { module: "mesh-tools", repo: "mesh-tools", path: "" };
/**
 * What `amqp-ping` requires, and what the substrate does not supply.
 *
 * The installer raises a broker, but as a bundle resource — plumbing, not a module the mesh has a
 * record of, so it provides nothing to anything. A module asking for `amqp` is asking for a
 * provider in the graph, and this is it. No build: its image is upstream.
 */
const PROVIDER = { module: "lavinmq", repo: "mesh-catalog", path: "modules/lavinmq" };
/** Named once, because the step title is also how later steps say what they waited on. */
const NEEDS = "the mesh runs a broker for that module to talk to";
const MODULE = { module: "amqp-ping", repo: "mesh-catalog", path: "modules/amqp-ping" };

const capability = await labIsUsable();
const binary = hostBinaryPath();
const installer = bootstrapBinaryPath();
const bundle = process.env["MESH_LAB_BUNDLE"] ?? "";
const catalogDir = process.env["MESH_LAB_CATALOG"] ?? "";
const source = process.env["MESH_LAB_SOURCE"] ?? "";
const sourceRef = process.env["MESH_LAB_SOURCE_REF"] ?? "";
const KEEP = !!process.env["MESH_LAB_KEEP"];
const FIXED_ID = process.env["MESH_LAB_INSTANCE_ID"] ?? (KEEP ? "fresh-mesh-live" : undefined);

/**
 * Where a repository other than the control plane's lives.
 *
 * Derived from `MESH_LAB_SOURCE` by swapping the last path segment, because every one of these
 * repositories sits beside the others under the same owner on the same forge. Overridable, so a
 * forge that is arranged differently does not need this bed edited.
 */
function forgeUrl(repo: string): string {
  const override = process.env[`MESH_LAB_SOURCE_${repo.toUpperCase().replaceAll("-", "_")}`];
  if (override) return override;
  return source.replace(/[^/]+\.git$/, `${repo}.git`);
}
/**
 * What to build, per repository.
 *
 * A branch is acceptable for an ordinary build; only genesis insists on a commit (ADR 0071). Per
 * repository rather than one value for all of them, because a change under test usually lives in
 * one repository and the rest should be built from what everyone else has — building them all from
 * a feature branch would prove that branch against itself.
 *
 *   MESH_LAB_BUILD_REF                 the default for every repository
 *   MESH_LAB_BUILD_REF_MESH_CATALOG    ...overridden for one
 */
function refFor(repo: string): string {
  const override = process.env[`MESH_LAB_BUILD_REF_${repo.toUpperCase().replaceAll("-", "_")}`];
  return override ?? process.env["MESH_LAB_BUILD_REF"] ?? "main";
}

/**
 * The shared base's manifest, on this workstation.
 *
 * The base is a repository with a manifest at its root (novox/hq ADR 0069), so unlike the
 * catalogue's modules it is not under `MESH_LAB_CATALOG`. Derived from that path on the convention
 * that the checkouts sit beside each other, and overridable for a layout where they do not.
 */
const baseManifest = process.env["MESH_LAB_BASE_MANIFEST"] ??
  resolve(catalogDir, "..", "..", BASE.repo, "module.json");

const skip =
  !capability.usable ? capability.why :
  !binary ? "MESH_LAB_HOST_BINARY is not set to a built mesh-host" :
  !installer ? "MESH_LAB_BOOTSTRAP_BINARY is not set to a built mesh-bootstrap" :
  !source ? "MESH_LAB_SOURCE is not set to the repository the control plane is built from" :
  !sourceRef ? "MESH_LAB_SOURCE_REF is not set to the commit to build" :
  !bundle || !existsSync(bundle) ? "MESH_LAB_BUNDLE is not set to a substrate template" :
  !catalogDir || !existsSync(catalogDir) ? "MESH_LAB_CATALOG is not set to mesh-catalog/modules" :
  false;

let instanceId = "";
let raised: GenesisResult;

// ---- talking to the machines ------------------------------------------------------------------

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(CONTROL, `docker exec mesh-control /mesh-control ${command}`, timeoutMs);
}

/**
 * Register a module from a manifest on this workstation.
 *
 * **The control plane runs in a container, so a file on the machine is not a file it can open.**
 * Pushing the manifest to the machine and naming that path got `no such file or directory` from
 * inside mesh-control, which is correct and was briefly mistaken for a missing manifest. It is
 * copied the last step of the way with `docker cp`.
 *
 * **Into the root, not into /tmp.** The control plane's image is a minimal one and has no `/tmp`
 * to copy into — `docker cp` says so in those words. `/` is the one directory every image has.
 */
async function registerModule(module: string, manifest: string): Promise<string> {
  assert.ok(existsSync(manifest), `no manifest for ${module} at ${manifest}`);
  const onMachine = `/tmp/${module}.json`;
  const inContainer = `/${module}.json`;
  await push(instanceId, CONTROL, manifest, onMachine);
  await must(CONTROL, `docker cp ${onMachine} mesh-control:${inContainer}`);
  return mesh(`module add ${inContainer}`);
}
function tokenFrom(said: string): string {
  const found = said.split("\n").map((l) => l.trim()).find((l) => l.length > 100 && !l.includes(" "));
  assert.ok(found, `no token in:\n${said}`);
  return found;
}

// ---- steps, recorded rather than thrown --------------------------------------------------------

interface Step { ok: boolean; why: string; said: string }
const steps = new Map<string, Step>();
const order: string[] = [];

/** Run a step, remember what it said, and never throw. A step whose predecessor failed is skipped. */
async function step(name: string, after_: string | null, fn: () => Promise<string>): Promise<void> {
  order.push(name);
  if (after_ && !steps.get(after_)?.ok) {
    steps.set(name, { ok: false, why: `not attempted — "${after_}" did not succeed`, said: "" });
    console.log(`SKIPPED  ${name}`);
    return;
  }
  console.log(`\n======== ${name} ========`);
  try {
    const said = await fn();
    steps.set(name, { ok: true, why: "", said });
    console.log(`OK       ${name}`);
  } catch (err) {
    const why = (err as Error).message;
    steps.set(name, { ok: false, why, said: "" });
    console.log(`FAILED   ${name}\n${why.split("\n").slice(0, 25).join("\n")}`);
  }
}

function report(name: string): string {
  const s = steps.get(name);
  if (!s) return `${name}: never ran`;
  const lines = order.map((n) => {
    const it = steps.get(n);
    return `  ${it?.ok ? "PASS" : "FAIL"}  ${n}`;
  });
  return `${s.why}\n\nWhere this bed got to:\n${lines.join("\n")}`;
}

before(async () => {
  if (skip) return;

  const bed = await raise(loadScenario(`scenarios/${SCENARIO}.yml`), {
    onProgress: (m) => console.log(`raise: ${m}`),
    ...(FIXED_ID ? { instanceId: FIXED_ID } : {}),
  });
  instanceId = bed.instanceId;
  console.log(`INSTANCE ${instanceId}${KEEP ? " (KEEP — will be left standing)" : ""}`);
  console.log(`NOTHING WAS LOADED: this scenario names no images. Every image on every machine ` +
    `below was pulled from the internet or built by the mesh.`);

  // ---- 1. GENESIS -----------------------------------------------------------------------------
  //
  // The shared description, the same one `genesis-single` calls. The bundle is the TEMPLATE with
  // nothing held: no image is pre-resolved, because none is here to resolve to.
  await step("novox becomes a mesh of one, raised by the installer", null, async () => {
    try {
      raised = await genesis({
        instanceId,
        node: CONTROL,
        installer: installer as string,
        catalogDir,
        // The broker's advertised address, corrected.
        //
        // The template hardcodes 192.0.2.10:5671 — the address of the anchor in the single-machine
        // bed. A token carries this verbatim as the endpoint an enrolling node dials, so on a mesh
        // whose anchor is somewhere else every node, including this one, would enrol against an
        // address nothing answers on. The installer refuses to guess it and says so, which is
        // right: it does not know what this machine is called from outside.
        bundleTemplate: substrateBundle(bundle, []).replaceAll("192.0.2.10:5671", `${ANCHOR}:5671`),
        registry: REGISTRY,
        source,
        sourceRef,
        log: (m) => console.log(m),
      });
    } catch (err) {
      throw new Error(`the installer never ran: ${(err as Error).message}`);
    }
    if (!raised.ok) throw new Error(`${raised.step || "no step named"}: ${raised.why}\n\n${raised.report.join("\n")}`);
    return raised.report.join("\n");
  });

  // ---- 2. JOINING -----------------------------------------------------------------------------
  //
  // Host binary and a token. novox is NOT in this loop — the installer enrolled it, and enrolling
  // it again would offer the mesh a second identity for a node it already knows.
  await step("three machines join it across the household gateway",
    "novox becomes a mesh of one, raised by the installer", async () => {
    const said: string[] = [];
    for (const machine of HOME_NODES) {
      await mesh(`node add ${machine}`);
      const token = tokenFrom(await mesh(`token issue --node ${machine}`));
      const out = await must(machine, `${HOST_PATH} enrol --token ${quote(token)}`, 180_000);
      assert.match(out, new RegExp(`enrolled as ${machine}`), out);
      await must(machine, `nohup ${HOST_PATH} run > /var/log/mesh-host.log 2>&1 & sleep 3`);
      said.push(`  ${machine} enrolled and running`);
    }
    const nodes = await mesh("node list");
    said.push(nodes.trim());
    return said.join("\n");
  });

  // ---- 3. THE MESH BUILDS THE SHARED BASE -----------------------------------------------------
  //
  // The toolchain and runtime every module with code of its own stands on. It is a module, and it
  // is built like one — cloned from the forge by the builder installing put here, compiled on the
  // machine, published into the mesh's own registry.
  await step("the mesh builds the shared base from source",
    "three machines join it across the household gateway", async () => {
    // Registered from the manifest the builder will also read, so what the mesh holds and what it
    // builds are the same description of the same module.
    //
    // **Not swallowed.** This call used to end in `.catch(() => {})`, on the reasoning that the
    // base might already be known. It hid a real failure — the manifest was being named at a path
    // inside a container that had never seen it — and the step passed anyway, because a base with
    // nothing to stand on builds whether or not the mesh has a record of it. The next step, which
    // needs that record, is where it surfaced.
    await registerModule(BASE.module, baseManifest);
    const built = await mesh(
      `build ${forgeUrl(BASE.repo)} --ref ${refFor(BASE.repo)} --wait 1200s`, 1_500_000);
    assert.doesNotMatch(built, /failed/i, built);
    return built;
  });

  // ---- 4. AND A MODULE STANDING ON IT ---------------------------------------------------------
  await step("the mesh builds a module standing on that base",
    "the mesh builds the shared base from source", async () => {
    await registerModule(MODULE.module, resolve(catalogDir, MODULE.module, "module.json"));
    const built = await mesh(
      `build ${forgeUrl(MODULE.repo)} --path ${MODULE.path} --ref ${refFor(MODULE.repo)} --wait 1200s`,
      1_500_000);
    assert.doesNotMatch(built, /failed/i, built);
    // The point of the whole step: what came out is named by a digest this mesh's registry
    // assigned, not by a placeholder and not by a tag.
    const builds = await mesh(`builds ${MODULE.module}`);
    assert.match(builds, /sha256:[0-9a-f]{12}/,
      `the build recorded no digest — the module is not pinned to anything this registry serves:\n${builds}`);
    return `${built}\n${builds}`;
  });

  // ---- 4b. WHAT THE MODULE NEEDS --------------------------------------------------------------
  //
  // `amqp-ping` requires the `amqp` provision, and the mesh refused to place it: "nothing provides
  // amqp, wanted by amqp-ping". That refusal is correct and is the reason this step exists rather
  // than the reason to pick an easier module. **The substrate's broker is not a provider.** It is
  // raised by the installer as part of the bundle, so it is a running container and not a module
  // with something to offer — the mesh's own plumbing, not an entry in its graph. A module that
  // wants a broker wants one the mesh knows about.
  //
  // `lavinmq` is that module. It was first added here on the belief that it needed no building —
  // its broker is an upstream image — and the mesh refused it: two of its three containers named a
  // placeholder digest, "which is never a real image". That was right. The broker is upstream, but
  // the module is not only the broker: it carries a run-once bootstrap that writes the broker's
  // configuration, a provisioner that grants each consumer its own vhost and user, tools and an
  // event consumer. All of that is its own code and has to be built like anything else.
  await step(NEEDS, "the mesh builds a module standing on that base", async () => {
    await registerModule(PROVIDER.module, resolve(catalogDir, PROVIDER.module, "module.json"));
    const built = await mesh(
      `build ${forgeUrl(PROVIDER.repo)} --path ${PROVIDER.path} --ref ${refFor(PROVIDER.repo)} --wait 1200s`,
      1_500_000);
    assert.doesNotMatch(built, /failed/i, built);
    await mesh(`assign ${CONTROL} ${PROVIDER.module}`);
    await mesh(`push ${CONTROL}`, 600_000);
    for (let i = 0; i < 60; i++) {
      const ps = (await on(CONTROL, `docker ps --format '{{.Names}}\t{{.Status}}'`)).out;
      const line = ps.split("\n").find((l) => l.includes(PROVIDER.module));
      if (line && /Up /.test(line)) return ps;
      await new Promise((r) => setTimeout(r, 5_000));
    }
    throw new Error(`${PROVIDER.module} never came up on ${CONTROL}:\n` +
      (await on(CONTROL, `docker ps -a --format '{{.Names}}\t{{.Status}}'`)).out);
  });

  // ---- 5. THE ANCHOR RUNS IT ------------------------------------------------------------------
  //
  // The machine that built it. This is the case every earlier proof covered, and it is here as the
  // control for step 6: if this fails, step 6's failure says nothing about fetching.
  await step("the anchor runs the module the mesh built", NEEDS, async () => {
    await mesh(`module issue ${MODULE.module} --node ${CONTROL}`).catch(() => {});
    await mesh(`assign ${CONTROL} ${MODULE.module}`);
    await mesh(`push ${CONTROL}`, 600_000);
    for (let i = 0; i < 40; i++) {
      const ps = (await on(CONTROL, `docker ps --format '{{.Names}}\t{{.Status}}'`)).out;
      if (/amqp-ping/.test(ps) && /Up /.test(ps.split("\n").find((l) => l.includes("amqp-ping")) ?? "")) {
        return ps;
      }
      await new Promise((r) => setTimeout(r, 5_000));
    }
    throw new Error(`amqp-ping never came up on ${CONTROL}:\n` +
      (await on(CONTROL, `docker ps -a --format '{{.Names}}\t{{.Status}}'`)).out);
  });

  // ---- 6. AND A MACHINE THAT DID NOT BUILD IT -------------------------------------------------
  //
  // **The thing nothing has ever checked.** ace did not build this image and has never seen it. To
  // run it, it must fetch it from the mesh's registry — and a joined node has no account there.
  // The mesh grants a consumer a credential for a database; it does not yet do so for the store
  // its own images live in (novox/hq issue 042).
  //
  // Asked anyway, and asked LAST, so that when it fails the five steps above still stand as
  // evidence of what does work.
  await step(`a joined machine runs the module the mesh built`,
    "the anchor runs the module the mesh built", async () => {
    await mesh(`module issue ${MODULE.module} --node ${SECOND}`).catch(() => {});
    await mesh(`assign ${SECOND} ${MODULE.module}`);
    await mesh(`push ${SECOND}`, 600_000);
    for (let i = 0; i < 40; i++) {
      const ps = (await on(SECOND, `docker ps --format '{{.Names}}\t{{.Status}}'`)).out;
      const line = ps.split("\n").find((l) => l.includes("amqp-ping"));
      if (line && /Up /.test(line)) return ps;
      await new Promise((r) => setTimeout(r, 5_000));
    }
    const state = (await on(SECOND, `docker ps -a --format '{{.Names}}\t{{.Status}}'`)).out;
    const log = (await on(SECOND, `tail -40 /var/log/mesh-host.log`)).out;
    throw new Error(
      `amqp-ping never came up on ${SECOND} — the machine that did NOT build it.\n\n` +
      `containers:\n${state}\n\nwhat the host said:\n${log}`);
  });

  console.log(`\n================ WHAT THIS MESH DID FOR ITSELF ================`);
  for (const n of order) console.log(`  ${steps.get(n)?.ok ? "PASS" : "FAIL"}  ${n}`);
}, { timeout: 7_200_000 });

after(async () => {
  if (KEEP) {
    console.log(`\nLEFT STANDING: ${instanceId} — not destroyed (MESH_LAB_KEEP).`);
    return;
  }
  if (instanceId) await destroy(instanceId);
  await destroyAll(`${SCENARIO}-`);
}, { timeout: 900_000 });

for (const name of [
  "novox becomes a mesh of one, raised by the installer",
  "three machines join it across the household gateway",
  "the mesh builds the shared base from source",
  "the mesh builds a module standing on that base",
  NEEDS,
  "the anchor runs the module the mesh built",
  "a joined machine runs the module the mesh built",
]) {
  test(name, { skip, timeout: 60_000 }, () => {
    assert.ok(steps.get(name)?.ok, report(name));
  });
}