import { test } from "node:test";
import assert from "node:assert/strict";
import { mkdtemp, writeFile, readFile, readdir } from "node:fs/promises";
import { tmpdir } from "node:os";
import { join } from "node:path";

import { compareVersions } from "../dist/primitives/index.js";
import { registerModuleTools, collectTools, resetTools, serveTools, listTools, invokeTool } from "../dist/tools/index.js";
import { runProvisioner } from "../dist/provisioner/index.js";
import { emit, on, type Event } from "../dist/events/index.js";
import { useBroker } from "../dist/messaging/index.js";

test("semver orders releases", () => {
  assert.equal(compareVersions("1.2.3", "1.2.10"), -1);
  assert.equal(compareVersions("2.0.0", "1.9.9"), 1);
  assert.equal(compareVersions("v1.0.0", "1.0.0"), 0);
});

test("module tools register and collect, a thrower is skipped not fatal", () => {
  resetTools();
  registerModuleTools("umami", () => [
    { name: "umami_stats", description: "d", input: {}, run: async () => 1 },
  ]);
  registerModuleTools("broken", () => {
    throw new Error("no token");
  });
  const collected = collectTools({});
  const umami = collected.find((c) => c.module === "umami");
  const broken = collected.find((c) => c.module === "broken");
  assert.equal(umami?.tools.length, 1);
  assert.equal(broken?.tools.length, 0);
});

test("provisioner creates each consumer with the mesh's login and password, removes on withdrawal", async () => {
  const dir = await mkdtemp(join(tmpdir(), "prov-"));
  const created: { as: string; password: string; values: unknown }[] = [];
  const removed: string[] = [];

  // What the mesh delivers: the password it minted (as the host leaves it after unsealing) and a
  // contributions file naming the consumer's login and where that password is.
  await writeFile(join(dir, "webapp.secret"), "minted-pw\n");
  const receives = join(dir, "analytics.json");
  const doc = (given: unknown[]): string =>
    JSON.stringify({ contributions: 1, requirement: "analytics", given });
  await writeFile(
    receives,
    doc([{ from: "webapp", node: "anchor", as: "webapp-anchor", secret: join(dir, "webapp.secret"), values: { name: "webapp" } }]),
  );

  const stop = runProvisioner(
    "analytics",
    {
      async create(p) {
        created.push({ as: p.as, password: p.password, values: p.values });
      },
      async remove(p) {
        removed.push(p.as);
      },
    },
    { receives, everyMs: 20 },
  );

  await waitFor(() => created.length === 1, 2000);
  // The adapter is handed the mesh's login and the mesh's password — not one it generated, and the
  // trailing newline of the unsealed file is stripped.
  assert.equal(created[0].as, "webapp-anchor");
  assert.equal(created[0].password, "minted-pw");
  assert.deepEqual(created[0].values, { name: "webapp" });

  // Withdraw: the mesh drops the consumer from the file → the harness removes it via the adapter.
  await writeFile(receives, doc([]));
  await waitFor(() => removed.length === 1, 2000);
  assert.equal(removed[0], "webapp-anchor");
  stop();
});

test("modules can SERVE: a real async tool, loaded and invoked over the broker", async () => {
  resetTools();

  // Stand up a fake upstream the tool actually calls over the network — proving a tool that does
  // real work (not a pure function) serves end to end.
  const { createServer } = await import("node:http");
  const server = createServer((_req, res) => {
    res.setHeader("content-type", "application/json");
    res.end(JSON.stringify({ id: "site-123" }));
  });
  await new Promise<void>((r) => server.listen(0, r));
  const addr = server.address() as { port: number };
  const base = `http://127.0.0.1:${addr.port}`;

  // A module registers its tool exactly as umami does — the tool calls the upstream and returns a
  // result computed from it.
  registerModuleTools("demo", () => [
    {
      name: "create_site",
      description: "register a site and return its snippet",
      input: { domain: { type: "string" } },
      run: async (args) => {
        const res = await fetch(`${base}/api/websites`, { method: "POST" });
        const { id } = (await res.json()) as { id: string };
        return { domain: String(args.domain), snippet: `<script data-website-id="${id}"></script>` };
      },
    },
  ]);

  const broker = memBroker();
  const stop = await serveTools(broker, {});

  // Invoke it the way a caller (mesh-control's command API) would — over the broker, by module and
  // tool, each served on its own key `demo.create_site` (novox/hq ADR 0047).
  const result = (await invokeTool(broker, "demo", "create_site", { domain: "my-app" })) as { snippet: string };
  assert.match(result.snippet, /data-website-id="site-123"/);

  // Discovery works, and an unknown tool is refused rather than silently dropped.
  assert.deepEqual(listTools({}).map((t) => t.name), ["create_site"]);
  await assert.rejects(invokeTool(broker, "demo", "nope", {}));

  stop();
  server.close();
});

test("serving refuses one module exposing two tools of the same name", async () => {
  // Two *modules* may share a tool name — each is served on its own `module.tool` key (ADR 0047).
  // What is refused is one module exposing the same name twice, where the key would collide.
  resetTools();
  registerModuleTools("a", () => [
    { name: "dup", description: "", input: {}, run: async () => 1 },
    { name: "dup", description: "", input: {}, run: async () => 2 },
  ]);
  await assert.rejects(serveTools(memBroker(), {}), /exposes two tools named dup/);
});

// A minimal in-memory broker: request routes to a registered handle, and publish routes to every
// subscriber whose topic pattern matches. Enough to exercise tools and events; the real binding is
// the mesh's AMQP one, provided by the hosting runtime.
function memBroker() {
  const handlers = new Map<string, (b: unknown) => Promise<unknown>>();
  const subs: { pattern: string; handler: (env: { key: string; node: string; body: unknown }) => Promise<void> }[] = [];
  return {
    async request<Req, Res>(key: string, body: Req): Promise<Res> {
      const h = handlers.get(key);
      if (!h) throw new Error(`no handler for ${key}`);
      return (await h(body)) as Res;
    },
    async handle<Req, Res>(key: string, handler: (b: Req) => Promise<Res>): Promise<() => void> {
      handlers.set(key, handler as (b: unknown) => Promise<unknown>);
      return () => handlers.delete(key);
    },
    async publish<T>(env: { key: string; node: string; body: T }): Promise<void> {
      for (const s of subs) if (topicMatch(s.pattern, env.key)) await s.handler(env);
    },
    async subscribe<T>(pattern: string, handler: (env: { key: string; node: string; body: T }) => Promise<void>): Promise<() => void> {
      const entry = { pattern, handler: handler as (env: { key: string; node: string; body: unknown }) => Promise<void> };
      subs.push(entry);
      return () => {
        const i = subs.indexOf(entry);
        if (i >= 0) subs.splice(i, 1);
      };
    },
    async close(): Promise<void> {},
  };
}

// AMQP topic matching: `*` one segment, `#` any run of segments.
function topicMatch(pattern: string, key: string): boolean {
  if (pattern === "#") return true;
  const p = pattern.split(".");
  const k = key.split(".");
  let pi = 0;
  let ki = 0;
  while (pi < p.length) {
    if (p[pi] === "#") return true; // simplification: # only as a trailing wildcard
    if (ki >= k.length) return false;
    if (p[pi] !== "*" && p[pi] !== k[ki]) return false;
    pi++;
    ki++;
  }
  return ki === k.length;
}

test("events: a module emits, a listener and the audit sink (#) both receive it, with metadata", async () => {
  const broker = memBroker();
  useBroker(() => broker);

  process.env.MESH_MODULE = "umami";
  process.env.MESH_NODE = "anchor";

  const heard: Event[] = [];
  const audited: Event[] = [];
  await on("module.umami.#", async (e) => void heard.push(e));
  await on("#", async (e) => void audited.push(e)); // the audit logger is just this

  await emit("module.umami.site.created", { domain: "my-app" });
  await emit("module.plex.play.started", { title: "x" }); // a different module's event

  // The umami listener heard only umami's event; the audit sink heard both.
  assert.deepEqual(heard.map((e) => e.type), ["module.umami.site.created"]);
  assert.deepEqual(audited.map((e) => e.type), ["module.umami.site.created", "module.plex.play.started"]);

  // The metadata an audit trail needs is present — read back from the ADR 0042 headers, not the body.
  const e = heard[0];
  assert.equal(e.source, "umami");
  assert.equal(e.node, "anchor");
  assert.equal((e.body as { domain: string }).domain, "my-app");
  assert.match(e.at, /^\d{4}-\d{2}-\d{2}T/);
  // Every event carries a unique id (x-event-id) — the handle a consumer dedups on.
  assert.ok(e.id, "event has an x-event-id");
  assert.notEqual(audited[0].id, audited[1].id);
  // The body is exactly the domain payload — provenance never leaks into it.
  assert.deepEqual(Object.keys(e.body as object), ["domain"]);

  delete process.env.MESH_MODULE;
  delete process.env.MESH_NODE;
});

async function waitFor(cond: () => boolean, ms: number): Promise<void> {
  const start = Date.now();
  while (!cond()) {
    if (Date.now() - start > ms) throw new Error("timed out waiting");
    await new Promise((r) => setTimeout(r, 10));
  }
}