'use strict';
// BL-0051: discovery harvest routes, per-user refresh and nightly state, against a fixture AniList server.
const test = require('node:test'), assert = require('node:assert/strict');
const fs = require('fs'), os = require('os'), path = require('path'), net = require('net'), http = require('http'), crypto = require('crypto');
const { spawn } = require('child_process');

const FIXTURES = path.join(__dirname, 'fixtures', 'anilist');
const fixture = name => JSON.parse(fs.readFileSync(path.join(FIXTURES, `${name}.json`), 'utf8'));
const sleep = ms => new Promise(resolve => setTimeout(resolve, ms));

// The anchor title carries no tags or staff, so a run stays at title + recs + fresh (the client allows 25 a minute).
function fixtureBodies() {
  const title = fixture('title');
  Object.assign(title.data.Media, { genres: [], tags: [], staff: { edges: [] } });
  const recs = fixture('recs');
  recs.data.Media.recommendations.nodes[0].rating = 500;
  return { title, recs, creator: fixture('creator'), tagtop: fixture('tagtop'), fresh: fixture('fresh') };
}

async function startAniList({ delayMs = 0 } = {}) {
  const bodies = fixtureBodies(), seen = [];
  const server = http.createServer((req, res) => {
    let raw = '';
    req.on('data', chunk => { raw += chunk; });
    req.on('end', async () => {
      const query = String(JSON.parse(raw || '{}').query || '');
      const kind = query.includes('recommendations') ? 'recs' : query.includes('Staff(') ? 'creator'
        : /genre_in|tag_in/.test(query) ? 'tagtop' : query.includes('startDate_greater') ? 'fresh' : 'title';
      seen.push(kind);
      if (delayMs) await sleep(delayMs);
      res.writeHead(200, { 'content-type': 'application/json' });
      res.end(JSON.stringify(bodies[kind]));
    });
  });
  await new Promise(resolve => server.listen(0, '127.0.0.1', resolve));
  return { url: `http://127.0.0.1:${server.address().port}/`, seen, close: () => new Promise(resolve => server.close(resolve)) };
}

async function freePort() {
  const listener = net.createServer();
  await new Promise(resolve => listener.listen(0, '127.0.0.1', resolve));
  const port = listener.address().port;
  await new Promise(resolve => listener.close(resolve));
  return port;
}

const hashPw = pw => { const salt = crypto.randomBytes(16).toString('hex'); return salt + ':' + crypto.scryptSync(pw, salt, 32).toString('hex'); };
const sha = s => crypto.createHash('sha256').update(s).digest('hex');
const USERS = { boss: { admin: true, discovery: false }, alice: { discovery: true }, bob: { discovery: true }, carol: { discovery: false } };

// A disposable reader with ready-made accounts and sessions; nightly harvests are off unless the store says otherwise.
async function startReader({ anilist, discovery = {} } = {}) {
  const root = fs.mkdtempSync(path.join(os.tmpdir(), 'mc-discovery-server-'));
  const library = path.join(root, 'library'), data = path.join(root, 'data');
  fs.mkdirSync(path.join(library, 'Example Manga'), { recursive: true });
  fs.writeFileSync(path.join(library, 'Example Manga', 'notes.txt'), 'not a chapter');
  fs.mkdirSync(path.join(data, 'scraper'), { recursive: true });
  fs.writeFileSync(path.join(data, 'scraper', 'queue.json'), JSON.stringify({ queue: [] }));
  const users = {}, sessions = {}, cookies = {};
  for (const [name, spec] of Object.entries(USERS)) {
    users[name] = { name, hash: hashPw(`${name}-password`), admin: !!spec.admin, created: Date.now(),
      settings: { discoveryEnabled: spec.discovery } };
    const token = crypto.randomBytes(32).toString('base64url');
    sessions[sha(token)] = { u: name, t: Date.now() };
    cookies[name] = `sid=${token}`;
  }
  fs.writeFileSync(path.join(data, 'db.json'), JSON.stringify({ users, sessions,
    discoveryFeedback: { alice: { 'anilist:101': 'interested' } } }));
  fs.writeFileSync(path.join(data, 'discovery.json'), JSON.stringify({ schema: 1, revision: 0, candidates: {}, feeds: {},
    lastRun: { status: 'never' }, harvest: null, settings: { harvestEnabled: false, harvestAt: '03:30' },
    nightly: { lastDate: null }, ...discovery }));

  const port = await freePort(), output = [];
  const child = spawn(process.execPath, ['server.js'], { cwd: path.resolve(__dirname, '..'), windowsHide: true,
    env: { ...process.env, LIBRARY: library, DATA: data, PORT: String(port), SCAN_INTERVAL: '0', FULL_SCAN_INTERVAL: '0',
      SCRAPER_URL: 'http://127.0.0.1:9', SCRAPER_TOKEN: 'fixture-token', SCRAPER_TOKEN_FILE: '', BACKUP: '',
      DISCOVERY_ANILIST_URL: anilist ? anilist.url : 'http://127.0.0.1:9/', DISCOVERY_HARVEST_AT: '' } });
  child.stdout.on('data', d => output.push(String(d)));
  child.stderr.on('data', d => output.push(String(d)));
  const base = `http://127.0.0.1:${port}`;
  let ready = false;
  for (let n = 0; n < 100 && !ready; n++) {
    ready = await fetch(base + '/health').then(r => r.ok).catch(() => false);
    if (!ready) await sleep(50);
  }
  assert.ok(ready, output.join(''));
  const call = async (who, method, url, body) => {
    const response = await fetch(base + url, { method, headers: { cookie: cookies[who], ...(body ? { 'content-type': 'application/json' } : {}) },
      body: body === undefined ? undefined : JSON.stringify(body) });
    return { status: response.status, body: await response.json().catch(() => null) };
  };
  return {
    root, library, data, output,
    get: (who, url) => call(who, 'GET', url),
    post: (who, url, body = {}) => call(who, 'POST', url, body),
    async stop() {
      await new Promise(resolve => { if (child.exitCode !== null) return resolve(); child.once('exit', resolve); child.kill(); });
      fs.rmSync(root, { recursive: true, force: true });
    },
  };
}

async function until(check, what, timeoutMs = 20000) {
  const deadline = Date.now() + timeoutMs;
  let last;
  while (Date.now() < deadline) {
    last = await check();
    if (last) return last;
    await sleep(100);
  }
  assert.fail(`Timed out waiting for ${what}`);
}
const idle = (reader, who) => until(async () => {
  const { body } = await reader.get(who, '/api/discovery');
  return body.refresh.state === 'idle' ? body : null;
}, `${who}'s refresh to finish`);
const harvestDone = reader => until(async () => {
  const { body } = await reader.get('boss', '/api/admin/discovery');
  return !body.currentHarvest && body.harvest && body.harvest.status !== 'running' ? body : null;
}, 'the harvest to finish');

function snapshot(dir) {
  const out = {};
  const walk = rel => {
    for (const entry of fs.readdirSync(path.join(dir, rel), { withFileTypes: true })) {
      const child = path.join(rel, entry.name), stat = fs.statSync(path.join(dir, child));
      out[child] = entry.isDirectory() ? 'dir' : `${stat.size}:${stat.mtimeMs}`;
      if (entry.isDirectory()) walk(child);
    }
  };
  walk('');
  return out;
}

test('refresh requires opt-in, queues, runs and rescores only the caller', { timeout: 60000 }, async () => {
  const anilist = await startAniList();
  const reader = await startReader({ anilist });
  try {
    assert.equal((await reader.post('boss', '/api/admin/discovery/run')).status, 200);
    await until(async () => (await reader.get('boss', '/api/admin/discovery')).body.currentRun?.status === 'success', 'the first run');
    const bobBefore = (await reader.get('bob', '/api/discovery')).body;
    assert.ok(bobBefore.generatedAt);
    assert.deepEqual(bobBefore.refresh, { state: 'idle' });

    const refused = await reader.post('carol', '/api/discovery/refresh');
    assert.equal(refused.status, 403);

    const accepted = await reader.post('alice', '/api/discovery/refresh');
    assert.equal(accepted.status, 200, JSON.stringify(accepted.body));
    assert.match(accepted.body.harvestId, /^[0-9a-f]{16}$/);
    assert.equal(accepted.body.position, 0);

    const alice = await idle(reader, 'alice');
    assert.ok(alice.items.some(item => item.candidateId === 'anilist:201'), JSON.stringify(alice.items.map(i => i.candidateId)));
    const rec = alice.items.find(item => item.candidateId === 'anilist:201');
    assert.ok(rec.reasons.some(reason => /recommend/.test(reason)));
    assert.ok(rec.candidate.fetchedAt);
    assert.deepEqual(anilist.seen.sort(), ['fresh', 'recs', 'title']);

    const bobAfter = (await reader.get('bob', '/api/discovery')).body;
    assert.equal(bobAfter.generatedAt, bobBefore.generatedAt);
    assert.deepEqual(bobAfter.items.map(i => i.candidateId), bobBefore.items.map(i => i.candidateId));

    const admin = (await reader.get('boss', '/api/admin/discovery')).body;
    assert.equal(admin.harvest.kind, 'user');
    assert.equal(admin.harvest.user, 'alice');
    assert.equal(admin.harvest.status, 'success');
    assert.equal(admin.harvest.requests, 3);
    assert.equal(admin.harvest.budget, 60);
    assert.ok(admin.cache.files >= 3 && admin.cache.bytes > 0, JSON.stringify(admin.cache));
    assert.ok(fs.existsSync(path.join(reader.data, 'discovery-cache')));
  } finally { await reader.stop(); await anilist.close(); }
});

test('second refresh within an hour is 429 with nextAllowedAt', { timeout: 60000 }, async () => {
  const anilist = await startAniList({ delayMs: 400 });
  const reader = await startReader({ anilist });
  try {
    assert.equal((await reader.post('bob', '/api/discovery/refresh')).status, 200);
    const duplicate = await reader.post('bob', '/api/discovery/refresh');
    assert.equal(duplicate.status, 409);
    const state = await idle(reader, 'bob');
    assert.ok(Date.parse(state.refresh.nextAllowedAt) > Date.now() + 50 * 60000);

    const cooling = await reader.post('bob', '/api/discovery/refresh');
    assert.equal(cooling.status, 429);
    assert.equal(cooling.body.nextAllowedAt, state.refresh.nextAllowedAt);
    assert.equal(typeof cooling.body.error, 'string');
  } finally { await reader.stop(); await anilist.close(); }
});

test('admin harvest is admin-only and single-flight', { timeout: 60000 }, async () => {
  const anilist = await startAniList({ delayMs: 500 });
  const reader = await startReader({ anilist });
  try {
    assert.equal((await reader.post('alice', '/api/admin/discovery/harvest')).status, 403);
    const first = await reader.post('boss', '/api/admin/discovery/harvest');
    assert.equal(first.status, 200, JSON.stringify(first.body));
    assert.equal(first.body.position, 0);
    assert.equal((await reader.post('boss', '/api/admin/discovery/harvest')).status, 409);
    const running = (await reader.get('boss', '/api/admin/discovery')).body;
    assert.equal(running.currentHarvest.id, first.body.harvestId);
    assert.equal(running.currentHarvest.kind, 'admin');
    const done = await harvestDone(reader);
    assert.equal(done.harvest.kind, 'admin');
    assert.equal(done.harvest.budget, 300);
    // Afterwards every opted-in user was rescored.
    for (const who of ['alice', 'bob']) assert.ok((await reader.get(who, '/api/discovery')).body.generatedAt, who);
  } finally { await reader.stop(); await anilist.close(); }
});

test('settings validation', { timeout: 30000 }, async () => {
  const reader = await startReader();
  try {
    const before = (await reader.get('boss', '/api/admin/discovery')).body;
    assert.deepEqual(before.settings, { harvestEnabled: false, harvestAt: '03:30' });
    assert.equal(before.nextNightlyAt, null);
    assert.equal((await reader.post('alice', '/api/admin/discovery/settings', { harvestEnabled: true, harvestAt: '04:00' })).status, 403);
    for (const body of [{ harvestEnabled: true, harvestAt: '25:00' }, { harvestEnabled: true, harvestAt: '4:00' },
      { harvestEnabled: 'yes', harvestAt: '04:00' }, { harvestEnabled: true }, { harvestEnabled: true, harvestAt: '04:00', extra: 1 }]) {
      const response = await reader.post('boss', '/api/admin/discovery/settings', body);
      assert.equal(response.status, 400, JSON.stringify(body));
    }
    const saved = await reader.post('boss', '/api/admin/discovery/settings', { harvestEnabled: true, harvestAt: '23:59' });
    assert.equal(saved.status, 200);
    const after = (await reader.get('boss', '/api/admin/discovery')).body;
    assert.deepEqual(after.settings, { harvestEnabled: true, harvestAt: '23:59' });
    const next = new Date(after.nextNightlyAt);
    // The next slot today at 23:59, or "due now" when the test happens to run inside that minute.
    const atSlot = next.getHours() === 23 && next.getMinutes() === 59 && next.getTime() > Date.now() - 120000;
    assert.ok(atSlot || Math.abs(next.getTime() - Date.now()) < 120000, after.nextNightlyAt);
  } finally { await reader.stop(); }
});

test('interrupted harvest is marked on startup', { timeout: 30000 }, async () => {
  const reader = await startReader({ discovery: { harvest: { id: 'abc', kind: 'nightly', user: null, status: 'running',
    startedAt: '2026-10-24T03:30:00.000Z', requests: 12, budget: 300 } } });
  try {
    const { body } = await reader.get('boss', '/api/admin/discovery');
    assert.equal(body.harvest.status, 'interrupted');
    assert.equal(body.harvest.id, 'abc');
    assert.equal(body.harvest.requests, 12);
    assert.ok(Date.parse(body.harvest.finishedAt));
    assert.equal(body.currentHarvest, null);
  } finally { await reader.stop(); }
});

test('harvest never touches scraper queue or library', { timeout: 60000 }, async () => {
  const anilist = await startAniList();
  const reader = await startReader({ anilist });
  try {
    const libraryBefore = snapshot(reader.library), scraperBefore = snapshot(path.join(reader.data, 'scraper'));
    assert.equal((await reader.post('alice', '/api/discovery/refresh')).status, 200);
    await idle(reader, 'alice');
    assert.equal((await reader.post('boss', '/api/admin/discovery/harvest')).status, 200);
    await harvestDone(reader);
    assert.deepEqual(snapshot(reader.library), libraryBefore);
    assert.deepEqual(snapshot(path.join(reader.data, 'scraper')), scraperBefore);
  } finally { await reader.stop(); await anilist.close(); }
});