import { afterEach, beforeEach, describe, expect, it } from "vitest";
import { createServer, type IncomingMessage, type Server, type ServerResponse } from "node:http";
import { mkdtemp, rm } from "node:fs/promises";
import { tmpdir } from "node:os";
import path from "node:path";
import { buildCollector, type CollectorApp } from "./app.js";

// The Training section's proxy: reviewer-gated, forwards a fixed set of paths to the
// trainer's job API, passes its status codes through, and degrades cleanly when the trainer
// is not configured or not reachable. The trainer is faked with a bare node http server.

const REVIEWER = { user: "julian", pass: "review-pass-123" };
const basic = "Basic " + Buffer.from(`${REVIEWER.user}:${REVIEWER.pass}`).toString("base64");

let dir: string;
let fake: Server;
let fakeUrl: string;
let seen: { method: string; url: string; body: string }[];
let app: CollectorApp;

async function start(trainerUrl: string | null): Promise<void> {
  app = await buildCollector({ host: "127.0.0.1", port: 0, dataDir: dir, boothTokens: new Map(), reviewer: REVIEWER, trainerUrl }, { dbFile: ":memory:" });
  await app.ready();
}

beforeEach(async () => {
  dir = await mkdtemp(path.join(tmpdir(), "collector-"));
  seen = [];
  fake = createServer((req: IncomingMessage, res: ServerResponse) => {
    let body = "";
    req.on("data", (c) => (body += c));
    req.on("end", () => {
      seen.push({ method: req.method ?? "", url: req.url ?? "", body });
      const json = (code: number, obj: unknown) => {
        res.writeHead(code, { "content-type": "application/json" });
        res.end(JSON.stringify(obj));
      };
      if (req.url === "/health") return json(200, { ok: true, busy: false });
      if (req.url === "/readiness") return json(200, { ready: false, labelled: { total: 3 } });
      if (req.url === "/versions") return json(200, { versions: [{ version: "v1", written: true }] });
      if (req.url === "/jobs" && req.method === "GET") return json(200, { jobs: [{ id: "j1" }], current: null });
      if (req.url === "/jobs" && req.method === "POST") return body.includes('"busy"') ? json(409, { error: "a job is already running" }) : json(202, { id: "j2", status: "running" });
      if (req.url === "/jobs/j1") return json(200, { id: "j1", status: "done", log: "ok" });
      if (req.url === "/versions/v1/report") {
        res.writeHead(200, { "content-type": "text/markdown; charset=utf-8" });
        return res.end("# Body-type classifier v1\n");
      }
      return json(404, { error: "not found" });
    });
  });
  await new Promise<void>((r) => fake.listen(0, "127.0.0.1", r));
  const a = fake.address() as { port: number };
  fakeUrl = `http://127.0.0.1:${a.port}`;
});
afterEach(async () => {
  await app?.close();
  await new Promise<void>((r) => fake.close(() => r()));
  await rm(dir, { recursive: true, force: true });
});

describe("review page script", () => {
  it("parses as JavaScript (an apostrophe in a template literal once broke the whole page)", async () => {
    const { reviewPage } = await import("./review-page.js");
    const html = reviewPage();
    const script = html.slice(html.indexOf("<script>") + 8, html.lastIndexOf("</script>"));
    expect(() => new Function(script)).not.toThrow();
  });
});

describe("training proxy", () => {
  it("is hidden when no trainer is configured", async () => {
    await start(null);
    const s = await app.inject({ method: "GET", url: "/api/training/status", headers: { authorization: basic } });
    expect(s.json()).toEqual({ configured: false });
    const j = await app.inject({ method: "POST", url: "/api/training/jobs", headers: { authorization: basic }, payload: { kind: "train" } });
    expect(j.statusCode).toBe(503);
  });

  it("aggregates status and forwards jobs and reports behind the reviewer login", async () => {
    await start(fakeUrl);
    expect((await app.inject({ method: "GET", url: "/api/training/status" })).statusCode).toBe(401);
    const s = await app.inject({ method: "GET", url: "/api/training/status", headers: { authorization: basic } });
    expect(s.statusCode).toBe(200);
    const body = s.json();
    expect(body.configured).toBe(true);
    expect(body.reachable).toBe(true);
    expect(body.readiness.labelled.total).toBe(3);
    expect(body.versions[0].version).toBe("v1");
    expect(body.jobs[0].id).toBe("j1");

    const j = await app.inject({
      method: "POST",
      url: "/api/training/jobs",
      headers: { authorization: basic },
      payload: { kind: "train", mode: "features", minAccuracy: 0.9, secret: "nope", version: "v2" },
    });
    expect(j.statusCode).toBe(202);
    expect(j.json().id).toBe("j2");
    const posted = seen.find((r) => r.method === "POST")!;
    expect(JSON.parse(posted.body)).toEqual({ kind: "train", mode: "features", minAccuracy: 0.9, version: "v2" }); // unknown keys dropped

    const busy = await app.inject({ method: "POST", url: "/api/training/jobs", headers: { authorization: basic }, payload: { kind: "evaluate", version: "busy" } });
    expect(busy.statusCode).toBe(409); // the trainer's answer passes through

    const bad = await app.inject({ method: "POST", url: "/api/training/jobs", headers: { authorization: basic }, payload: { kind: "rm-rf" } });
    expect(bad.statusCode).toBe(400);

    const one = await app.inject({ method: "GET", url: "/api/training/jobs/j1", headers: { authorization: basic } });
    expect(one.json().status).toBe("done");
    expect((await app.inject({ method: "GET", url: "/api/training/jobs/..%2Fx", headers: { authorization: basic } })).statusCode).toBe(400);

    const rep = await app.inject({ method: "GET", url: "/api/training/versions/v1/report", headers: { authorization: basic } });
    expect(rep.statusCode).toBe(200);
    expect(rep.headers["content-type"]).toContain("text/markdown");
    expect(rep.body).toContain("# Body-type classifier v1");
  });

  it("reports an unreachable trainer without failing the page", async () => {
    await start("http://127.0.0.1:9"); // nothing listens on the discard port
    const s = await app.inject({ method: "GET", url: "/api/training/status", headers: { authorization: basic } });
    expect(s.statusCode).toBe(200);
    expect(s.json().reachable).toBe(false);
    const j = await app.inject({ method: "POST", url: "/api/training/jobs", headers: { authorization: basic }, payload: { kind: "train" } });
    expect(j.statusCode).toBe(502);
  });
});