/**
 * @file Tests for GET/POST /api/locks — the HTTP surface over
 * server/lib/named-lock.js. Boots a real Express app + in-memory-ish SQLite
 * (temp file) like the other route test files in this suite.
 * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
 */

const os = require("node:os");
const path = require("node:path");
const fs = require("node:fs");
const http = require("node:http");

const SUITE_ROOT = fs.mkdtempSync(path.join(os.tmpdir(), "ccam-locks-api-"));
process.env.DASHBOARD_DB_PATH = path.join(SUITE_ROOT, "dashboard.db");
process.env.LANES_ROOT = path.join(SUITE_ROOT, "lanes");

const { describe, it, before, after } = require("node:test");
const assert = require("node:assert/strict");

const { createApp } = require("../index");
const namedLock = require("../lib/named-lock");

let server;
let PORT;

before(async () => {
  const app = createApp();
  server = http.createServer(app);
  await new Promise((resolve) => server.listen(0, "127.0.0.1", resolve));
  PORT = server.address().port;
});
after(async () => {
  await new Promise((resolve) => server.close(resolve));
  fs.rmSync(SUITE_ROOT, { recursive: true, force: true });
});

function request(method, urlPath, body) {
  return new Promise((resolve, reject) => {
    const data = body ? JSON.stringify(body) : null;
    const req = http.request(
      {
        method,
        hostname: "127.0.0.1",
        port: PORT,
        path: urlPath,
        headers: {
          "Content-Type": "application/json",
          ...(data ? { "Content-Length": Buffer.byteLength(data) } : {}),
        },
      },
      (res) => {
        let raw = "";
        res.on("data", (chunk) => (raw += chunk));
        res.on("end", () => {
          let json = null;
          try {
            json = JSON.parse(raw);
          } catch {
            /* empty body is fine for some responses */
          }
          resolve({ status: res.statusCode, body: json });
        });
      }
    );
    req.on("error", reject);
    if (data) req.write(data);
    req.end();
  });
}

describe("GET /api/locks", () => {
  it("lists currently-held locks", async () => {
    namedLock.tryAcquire("api-build", "lane1");
    const res = await request("GET", "/api/locks");
    assert.equal(res.status, 200);
    assert.ok(res.body.locks.some((l) => l.name === "api-build" && l.holder === "lane1"));
    namedLock.release("api-build", "lane1");
  });
});

describe("POST /api/locks/:name/acquire", () => {
  it("acquires a free lock", async () => {
    const res = await request("POST", "/api/locks/api-acquire/acquire", { holder: "lane1" });
    assert.equal(res.status, 200);
    assert.deepEqual(res.body, { acquired: true });
    namedLock.release("api-acquire", "lane1");
  });

  it("409s with the current holder when already held", async () => {
    namedLock.tryAcquire("api-busy", "lane1");
    const res = await request("POST", "/api/locks/api-busy/acquire", { holder: "lane2" });
    assert.equal(res.status, 409);
    assert.equal(res.body.acquired, false);
    assert.equal(res.body.holder, "lane1");
    namedLock.release("api-busy", "lane1");
  });

  it("400s when holder is missing", async () => {
    const res = await request("POST", "/api/locks/api-nobody/acquire", {});
    assert.equal(res.status, 400);
    assert.equal(res.body.error.code, "EBADHOLDER");
  });
});

describe("POST /api/locks/:name/release", () => {
  it("releases a held lock", async () => {
    namedLock.tryAcquire("api-release", "lane1");
    const res = await request("POST", "/api/locks/api-release/release", { holder: "lane1" });
    assert.equal(res.status, 200);
    assert.equal(res.body.ok, true);
    assert.equal(namedLock.status("api-release").held, false);
  });

  it("409s when the holder doesn't match", async () => {
    namedLock.tryAcquire("api-release-2", "lane1");
    const res = await request("POST", "/api/locks/api-release-2/release", { holder: "lane2" });
    assert.equal(res.status, 409);
    assert.equal(res.body.error.code, "ENOTHOLDER");
    namedLock.release("api-release-2", "lane1");
  });

  it("404s when the lock doesn't exist", async () => {
    const res = await request("POST", "/api/locks/never-held/release", { holder: "lane1" });
    assert.equal(res.status, 404);
    assert.equal(res.body.error.code, "ENOLOCK");
  });
});