/**
 * @file Tests server/lib/db-backup.js and its Settings routes — a backup is a
 * complete, openable copy of the live database under a server-made name, no
 * `.partial` is left behind, rotation deletes only AgentHub's own
 * `agenthub-YYYYMMDD-HHMMSS.db` files (never a look-alike, a symlink or anything
 * else in the folder), the once-a-day schedule decision, and the folder check.
 * The settings file and the folders are temp paths.
 * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
 */

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

const ROOT = fs.mkdtempSync(path.join(os.tmpdir(), "agenthub-db-backup-"));
process.env.DASHBOARD_DB_PATH = path.join(ROOT, "dashboard.db");
process.env.AGENTHUB_SETTINGS_FILE = path.join(ROOT, "settings.env");
process.env.DASHBOARD_LIVENESS_PROBE = "0";
for (const k of ["AGENTHUB_BACKUP_DIR", "AGENTHUB_BACKUP_HOUR", "AGENTHUB_BACKUP_KEEP"]) {
  delete process.env[k];
}

const { createApp, startServer } = require("../index");
const { db, Database } = require("../db");
const backup = require("../lib/db-backup");

const folder = (name) => {
  const dir = path.join(ROOT, name);
  fs.mkdirSync(dir, { recursive: true });
  return dir;
};

let server;
let BASE;
before(async () => {
  server = await startServer(createApp(), 0);
  BASE = `http://127.0.0.1:${server.address().port}`;
});
after(() => {
  server?.close();
  fs.rmSync(ROOT, { recursive: true, force: true });
});

async function call(method, urlPath, body) {
  const res = await fetch(BASE + urlPath, {
    method,
    headers: body ? { "content-type": "application/json" } : {},
    body: body ? JSON.stringify(body) : undefined,
  });
  return { status: res.status, body: await res.json() };
}

describe("validateBackupDir", () => {
  it("accepts an existing writable folder and resolves it", () => {
    const dir = folder("ok");
    assert.equal(backup.validateBackupDir(`${dir}/./`), dir);
  });
  for (const [label, input] of [
    ["a relative path", "backups"],
    ["a missing folder", path.join(ROOT, "nope")],
    ["a control character", `${ROOT}/a\nb`],
  ]) {
    it(`refuses ${label}`, () => {
      assert.throws(() => backup.validateBackupDir(input), { code: "INVALID_PATH" });
    });
  }
  it("refuses a file", () => {
    const file = path.join(ROOT, "a-file");
    fs.writeFileSync(file, "x");
    assert.throws(() => backup.validateBackupDir(file), { code: "INVALID_PATH" });
  });
});

describe("runBackup", () => {
  it("writes a complete copy under a server-made name and leaves no .partial", async () => {
    const dir = folder("run");
    process.env.AGENTHUB_BACKUP_DIR = dir;
    db.prepare(
      "INSERT INTO sessions (id, name, status, started_at) VALUES ('backup-marker', 'm', 'completed', '2026-01-01T00:00:00Z')"
    ).run();
    const out = await backup.runBackup();
    assert.match(out.file, /^agenthub-\d{8}-\d{6}\.db$/);
    assert.deepEqual(fs.readdirSync(dir), [out.file]);
    const copy = new Database(path.join(dir, out.file), { readonly: true });
    try {
      assert.equal(copy.pragma("quick_check", { simple: true }), "ok");
      assert.equal(
        copy.prepare("SELECT name FROM sessions WHERE id = 'backup-marker'").get().name,
        "m"
      );
    } finally {
      copy.close();
    }
    assert.equal(backup.lastResult().ok, true);
  });

  it("refuses with no folder set", async () => {
    delete process.env.AGENTHUB_BACKUP_DIR;
    await assert.rejects(backup.runBackup(), { code: "ENOBACKUPDIR" });
  });
});

describe("rotate", () => {
  it("keeps the newest N of its own files and touches nothing else", () => {
    const dir = folder("rotate");
    const own = [
      "agenthub-20261001-020000.db",
      "agenthub-20261002-020000.db",
      "agenthub-20261003-020000.db",
      "agenthub-20261004-020000.db",
    ];
    const others = ["notes.txt", "agenthub-latest.db", "agenthub-20261001-020000.db.bak", "my.db"];
    for (const f of [...own, ...others]) fs.writeFileSync(path.join(dir, f), "x");
    const outside = path.join(ROOT, "outside.db");
    fs.writeFileSync(outside, "keep me");
    fs.symlinkSync(outside, path.join(dir, "agenthub-20250101-000000.db"));

    assert.deepEqual(backup.rotate(dir, 2).sort(), own.slice(0, 2));
    assert.deepEqual(
      fs.readdirSync(dir).sort(),
      [...own.slice(2), ...others, "agenthub-20250101-000000.db"].sort()
    );
    assert.equal(fs.readFileSync(outside, "utf8"), "keep me");
  });
});

describe("dueNow", () => {
  const cfg = { dir: "/backups", hour: 2, keep: 7 };
  const at = (h) => new Date(2026, 9, 8, h, 30);
  const today = [{ name: "agenthub-20261008-020000.db" }];
  const yesterday = [{ name: "agenthub-20261007-020000.db" }];
  it("waits for the hour", () => assert.equal(backup.dueNow(at(1), cfg, [], null), false));
  it("runs once the hour passed with no backup today", () =>
    assert.equal(backup.dueNow(at(9), cfg, yesterday, null), true));
  it("skips a day that already has one", () =>
    assert.equal(backup.dueNow(at(9), cfg, today, null), false));
  it("tries once a day, not every minute after a failure", () =>
    assert.equal(backup.dueNow(at(9), cfg, [], "20261008"), false));
  it("does nothing with no folder", () =>
    assert.equal(backup.dueNow(at(9), { ...cfg, dir: "" }, [], null), false));
});

describe("Settings routes", () => {
  it("GET answers the defaults with no folder", async () => {
    delete process.env.AGENTHUB_BACKUP_DIR;
    const { status, body } = await call("GET", "/api/settings/backup");
    assert.equal(status, 200);
    assert.equal(body.dir, "");
    assert.equal(body.hour, 2);
    assert.equal(body.keep, 7);
    assert.deepEqual(body.files, []);
  });

  it("PUT validates every field", async () => {
    for (const bad of [
      { dir: "relative" },
      { hour: 24 },
      { hour: 1.5 },
      { keep: 0 },
      { keep: "7" },
    ]) {
      const { status } = await call("PUT", "/api/settings/backup", bad);
      assert.equal(status, 400, JSON.stringify(bad));
    }
  });

  it("PUT persists to the settings file; POST /run starts a backup", async () => {
    const dir = folder("route");
    const put = await call("PUT", "/api/settings/backup", { dir, hour: 3, keep: 5 });
    assert.equal(put.status, 200);
    assert.equal(put.body.dir, dir);
    const saved = fs.readFileSync(process.env.AGENTHUB_SETTINGS_FILE, "utf8");
    assert.match(saved, new RegExp(`^AGENTHUB_BACKUP_DIR=${dir}$`, "m"));
    assert.match(saved, /^AGENTHUB_BACKUP_HOUR=3$/m);
    assert.match(saved, /^AGENTHUB_BACKUP_KEEP=5$/m);

    const run = await call("POST", "/api/settings/backup/run");
    assert.equal(run.status, 202);
    for (let i = 0; i < 100 && (await call("GET", "/api/settings/backup")).body.running; i++) {
      await new Promise((r) => setTimeout(r, 50));
    }
    const { body } = await call("GET", "/api/settings/backup");
    assert.equal(body.last.ok, true);
    assert.equal(body.files.length, 1);
    assert.match(body.files[0].name, /^agenthub-\d{8}-\d{6}\.db$/);
  });

  it("PUT with an empty folder turns backups off", async () => {
    const { status, body } = await call("PUT", "/api/settings/backup", { dir: "" });
    assert.equal(status, 200);
    assert.equal(body.dir, "");
    const run = await call("POST", "/api/settings/backup/run");
    assert.equal(run.status, 400);
    assert.equal(run.body.error.code, "ENOBACKUPDIR");
  });
});