/**
 * @file Tests the `systemd` row of scripts/plugin-doctor.js.
 *
 * The row exists for a failure nothing else in the report can see: a unit still
 * naming a retired plugin cache directory leaves a running, healthy-looking
 * dashboard that simply does not come back after the next reboot — it starts a
 * path Claude Code deleted during the update. Every other row would read OK.
 *
 * WARN and never FAIL: the dashboard in front of the user works, and plenty of
 * machines legitimately have no unit at all.
 * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
 */

const { describe, it, beforeEach, after } = require("node:test");
const assert = require("node:assert/strict");
const fs = require("node:fs");
const os = require("node:os");
const path = require("node:path");

const TMP_HOME = fs.mkdtempSync(path.join(os.tmpdir(), "agenthub-doctor-systemd-"));
const prevHome = process.env.HOME;
// Before anything resolves a unit path: `unitPath()` reads HOME, and a path
// computed against the real one makes these tests rewrite the developer's own
// ~/.config/systemd/user/agenthub.service.
process.env.HOME = TMP_HOME;
process.env.CLAUDE_HOME = path.join(TMP_HOME, ".claude");

const svc = require("../../scripts/systemd-service");
const { diagnose } = require("../../scripts/plugin-doctor");

const UNIT = svc.unitPath("agenthub");
const PLUGIN_ROOT = path.resolve(__dirname, "..", "..");

assert.ok(UNIT.startsWith(TMP_HOME + path.sep), `refusing to touch ${UNIT}`);

beforeEach(() => {
  fs.rmSync(UNIT, { force: true });
  // Claim systemd exists and the unit is running, so each test varies exactly
  // one thing: the unit file on disk.
  svc.__setExecImpl((args) => ({
    status: 0,
    stdout: args[0] === "is-active" ? "active\n" : "",
  }));
});

after(() => {
  svc.__reset();
  if (prevHome === undefined) delete process.env.HOME;
  else process.env.HOME = prevHome;
  delete process.env.CLAUDE_HOME;
  fs.rmSync(TMP_HOME, { recursive: true, force: true });
});

function row() {
  const found = diagnose().find((r) => r.label === "systemd");
  assert.ok(found, "the doctor must always emit a systemd row");
  return found;
}

function writeUnit(workingDir) {
  fs.mkdirSync(path.dirname(UNIT), { recursive: true });
  fs.writeFileSync(
    UNIT,
    "[Unit]\n# agenthub-managed-unit — regenerated on install, do not edit by hand\n" +
      `[Service]\nWorkingDirectory=${workingDir}\n`,
    "utf8"
  );
}

const linuxOnly = { skip: process.platform !== "linux" ? "systemd is Linux-only" : false };

describe("plugin-doctor: systemd row", linuxOnly, () => {
  it("warns, never fails, when the unit names a retired plugin root", () => {
    writeUnit("/plugins/cache/sg/agenthub/deadbeef");
    const r = row();

    assert.equal(r.level, "warn", "a working dashboard must not fail the doctor run");
    assert.match(r.detail, /previous plugin version/i);
    // The consequence is the whole point — a reader who does not know it will
    // ignore the row.
    assert.match(r.detail, /reboot/i);
    assert.match(r.detail, /plugin-bootstrap\.js --force|new Claude Code session/);
  });

  it("passes when the unit is current and running", () => {
    writeUnit(PLUGIN_ROOT);
    const r = row();

    assert.equal(r.level, "ok", r.detail);
    assert.match(r.detail, /current and running/i);
  });

  it("warns when the unit is current but stopped", () => {
    writeUnit(PLUGIN_ROOT);
    svc.__setExecImpl((args) => ({
      status: 3,
      stdout: args[0] === "is-active" ? "inactive\n" : "",
    }));

    const r = row();
    assert.equal(r.level, "warn");
    assert.match(r.detail, /not running/i);
  });

  it("reports no unit as fine, not as a problem", () => {
    // A plugin install without `agenthub service install` is a normal setup:
    // the server is started per session.
    const r = row();
    assert.equal(r.level, "ok", r.detail);
    assert.match(r.detail, /no unit/i);
  });

  it("warns about a unit it did not write, and never claims it is stale", () => {
    fs.mkdirSync(path.dirname(UNIT), { recursive: true });
    fs.writeFileSync(UNIT, "[Service]\nExecStart=/opt/someone-elses-agenthub\n", "utf8");

    const r = row();
    assert.equal(r.level, "warn");
    assert.match(r.detail, /not written by AgentHub|left untouched/i);
  });
});