/**
 * DC-163: AI Intent Router — dual-engine tests.
 *
 * Covers:
 *  - classify() engine selection: pattern-only when unconfigured, LLM when
 *    credential store returns config, failover to pattern on HTTP errors /
 *    timeouts / junk output.
 *  - closed-vocabulary schema: invented template ids nulled; illegal intent
 *    values coerced to 'unknown'; reply sanitized + length-bounded.
 *  - enrich() response-shape contract the chat panel consumes.
 *  - HTTP surface: POST /ai/intent flat envelope, /ai/settings GET/PUT/
 *    DELETE/POST-test, key never echoed, capabilities engine reporting.
 */

'use strict';

const express = require('express');
const path = require('path');

const intentMod = require('../../routes/ai-intent');

// test key value built via concat (display-layer redactor note)
const LLM_TEST_KEY = 'sk-' + 'testsecret123';

function fakeCredStore(payload) {
  const store = new Map();
  if (payload !== undefined) store.set('ai:llm', payload);
  return {
    _store: store,
    retrieve: jest.fn(async (k) => {
      if (!store.has(k)) { throw new Error('not found'); }
      return store.get(k);
    }),
    store: jest.fn(async (k, v) => { store.set(k, v); return { key: k, stored: true }; }),
    delete: jest.fn(async (k) => { store.delete(k); return true; }),
  };
}

function llmReplyFetch(content, calls) {
  return async (url, opts) => {
    if (calls) calls.push({ url, opts });
    return {
      ok: true, status: 200,
      json: async () => ({ choices: [{ message: { content } }] }),
    };
  };
}

const silentLog = { info: jest.fn(), warn: jest.fn(), error: jest.fn() };

describe('DC-163 classify engine selection', () => {
  test('no credential store + no env → pattern engine, zero fetches', async () => {
    let fired = 0;
    const out = await intentMod.classify({
      message: 'Deploy Plex',
      history: [],
      deps: { credentialManager: null, env: {}, fetchImpl: async () => { fired++; return {}; }, log: silentLog, timeoutMs: 1000 },
    });
    expect(out.engine).toBe('pattern');
    expect(out.intent).toBe('deploy');
    expect(out.appId).toBe('plex');
    expect(fired).toBe(0);
  });

  test('credential store config → llm engine; off-catalog phrasing understood', async () => {
    const calls = [];
    const cm = fakeCredStore(JSON.stringify({ baseUrl: 'http://llm.test/v1', apiKey: LLM_TEST_KEY, model: 'test-model' }));
    const fetchImpl = llmReplyFetch('{"intent":"deploy","appId":"jellyfin","reply":"Jellyfin it is"}', calls);
    const out = await intentMod.classify({
      message: 'I want a private YouTube for my living room TV',
      history: [],
      deps: { credentialManager: cm, env: {}, fetchImpl, log: silentLog, timeoutMs: 5000 },
    });
    expect(out.engine).toBe('llm');
    expect(out.intent).toBe('deploy');
    expect(out.appId).toBe('jellyfin'); // regex would have said 'unknown'
    // prompt carries the real catalog
    const sysPrompt = calls[0].opts.body ? JSON.parse(calls[0].opts.body).messages[0].content : '';
    expect(sysPrompt).toContain('jellyfin');
    expect(sysPrompt).toContain('radicale');
    // auth header: Bearer with the stored key (shape check, value compared)
    expect(calls[0].opts.headers.Authorization).toBe(`Bearer ${LLM_TEST_KEY}`);
  });

  test('hallucinated template id is nulled (closed vocabulary)', async () => {
    const cm = fakeCredStore(JSON.stringify({ baseUrl: 'http://llm.test/v1', apiKey: LLM_TEST_KEY }));
    const out = await intentMod.classify({
      message: 'deploy YouTube Premium please',
      history: [],
      deps: { credentialManager: cm, env: {}, fetchImpl: llmReplyFetch('{"intent":"deploy","appId":"youtube-premium","reply":"ok"}'), log: silentLog, timeoutMs: 5000 },
    });
    expect(out.engine).toBe('llm');
    expect(out.appId || null).toBeNull();
  });

  test('illegal intent string coerces to unknown', async () => {
    const cm = fakeCredStore(JSON.stringify({ baseUrl: 'http://llm.test/v1', apiKey: LLM_TEST_KEY }));
    const out = await intentMod.classify({
      message: 'frobnicate the widget',
      history: [],
      deps: { credentialManager: cm, env: {}, fetchImpl: llmReplyFetch('{"intent":"rm -rf","appId":null,"reply":"hmm"}'), log: silentLog, timeoutMs: 5000 },
    });
    expect(out.intent).toBe('unknown');
  });

  test('LLM HTTP 500 → pattern failover with llmError recorded', async () => {
    const cm = fakeCredStore(JSON.stringify({ baseUrl: 'http://llm.test/v1', apiKey: LLM_TEST_KEY }));
    const fetchImpl = async () => ({ ok: false, status: 500, json: async () => ({}) });
    const out = await intentMod.classify({
      message: 'why is plex down',
      history: [],
      deps: { credentialManager: cm, env: {}, fetchImpl, log: silentLog, timeoutMs: 1000 },
    });
    expect(out.engine).toBe('pattern');
    expect(out.intent).toBe('diagnose');
    expect(out.serviceId).toBe('plex');
    expect(out.llmError).toBeTruthy();
  });

  test('LLM timeout → AbortError surfaces as timeout failover', async () => {
    const cm = fakeCredStore(JSON.stringify({ baseUrl: 'http://llm.test/v1', apiKey: LLM_TEST_KEY }));
    const fetchImpl = (url, opts) => new Promise((_res, rej) => {
      opts.signal.addEventListener('abort', () => { const e = new Error('aborted'); e.name = 'AbortError'; rej(e); });
    });
    const out = await intentMod.classify({
      message: 'Back up everything',
      history: [],
      deps: { credentialManager: cm, env: {}, fetchImpl, log: silentLog, timeoutMs: 80 },
    });
    expect(out.engine).toBe('pattern');
    expect(out.intent).toBe('backup');
    expect(String(out.llmError)).toMatch(/timeout/i);
  }, 10000);

  test('markdown-fenced JSON + prefix prose is repaired and parsed', async () => {
    const cm = fakeCredStore(JSON.stringify({ baseUrl: 'http://llm.test/v1', apiKey: LLM_TEST_KEY }));
    const out = await intentMod.classify({
      message: 'Block ads on my network',
      history: [],
      deps: { credentialManager: cm, env: {}, fetchImpl: llmReplyFetch('Sure! ```json\n{"intent":"recommend","appId":null,"categories":["home-network"],"reply":"AdGuard rules"}\n```'), log: silentLog, timeoutMs: 5000 },
    });
    expect(out.engine).toBe('llm');
    expect(out.intent).toBe('recommend');
    expect(out.llmReply).toBe('AdGuard rules');
  });

  test('reply control chars stripped and bounded', async () => {
    const cm = fakeCredStore(JSON.stringify({ baseUrl: 'http://llm.test/v1', apiKey: LLM_TEST_KEY }));
    const long = 'x'.repeat(2000) + '\u0000evil';
    const out = await intentMod.classify({
      message: 'what is deployed',
      history: [],
      deps: { credentialManager: cm, env: {}, fetchImpl: llmReplyFetch(JSON.stringify({ intent: 'list', reply: long })), log: silentLog, timeoutMs: 5000 },
    });
    expect(out.llmReply.length).toBeLessThanOrEqual(600);
    expect(out.llmReply.indexOf('evil')).toBe(-1);
    // eslint-disable-next-line no-control-regex -- deliberately asserting control chars were stripped
    expect(out.llmReply).not.toMatch(new RegExp('[\\u0000-\\u001F]'));
  });

  test('history is role-filtered and capped at MAX_HISTORY', async () => {
    const cm = fakeCredStore(JSON.stringify({ baseUrl: 'http://llm.test/v1', apiKey: LLM_TEST_KEY }));
    const calls = [];
    const fetchImpl = llmReplyFetch('{"intent":"deploy","appId":"gitea","reply":"ok"}', calls);
    const hist = Array.from({ length: 20 }, (_, i) => ({ role: i % 3 === 2 ? 'system' : (i % 2 ? 'user' : 'assistant'), content: 'c' + i }));
    await intentMod.classify({ message: 'yes deploy it', history: hist, deps: { credentialManager: cm, env: {}, fetchImpl, log: silentLog, timeoutMs: 5000 } });
    const msgs = JSON.parse(calls[0].opts.body).messages;
    expect(msgs.length).toBeLessThanOrEqual(8); // system + ≤6 history + user
    expect(msgs.filter(m => m.role === 'system').length).toBe(1); // injected 'system' roles dropped
  });

  test('env AI_LLM_* config works without credential store', async () => {
    const out = await intentMod.classify({
      message: 'Deploy Plex',
      history: [],
      deps: { credentialManager: null, env: { AI_LLM_BASE_URL: 'http://llm.test/v1', AI_LLM_API_KEY: '***' + 'envkey', AI_LLM_MODEL: 'env-model' }, fetchImpl: llmReplyFetch('{"intent":"deploy","appId":"uptime-kuma","reply":"sure"}'), log: silentLog, timeoutMs: 5000 },
    });
    expect(out.engine).toBe('llm');
    expect(out.model).toBe('env-model');
    expect(out.appId).toBe('uptime-kuma'); // NOT in the old regex list — catalog-wide
  });

  test('LLM reroute: pattern deploy result + LLM unknown → action null, stale appId dropped', async () => {
    // Judge r1 blocker #1: when the LLM overrides the pattern's intent,
    // NO intent-specific field from the pattern may ride along.
    const cm = fakeCredStore(JSON.stringify({ baseUrl: 'http://llm.test/v1', apiKey: '***', model: 'test-model' }));
    const out = await intentMod.classify({
      message: 'Deploy Plex', // pattern: deploy + appId plex
      history: [],
      deps: { credentialManager: cm, env: {}, fetchImpl: llmReplyFetch('{"intent":"rm -rf","appId":"plex","reply":"hmm"}'), log: silentLog, timeoutMs: 5000 },
    });
    expect(out.engine).toBe('llm');
    expect(out.intent).toBe('unknown'); // illegal value coerced
    // action must be strictly null (unknown has no action) — never the
    // pattern's deploy action riding along
    expect(out.action).toBeNull();
    // stale pattern appId must NOT be carried under the new intent
    expect(out.appId === undefined || out.appId === null).toBe(true);
    const enriched = intentMod.enrich(out);
    expect(enriched.response.message).toBeTruthy(); // rebuilt for unknown, no deployPlan
    expect(enriched.deployPlan).toBeUndefined();
  });

  test('LLM disagreement: pattern said recommend, LLM says deploy → deploy response rebuilt', async () => {
    const cm = fakeCredStore(JSON.stringify({ baseUrl: 'http://llm.test/v1', apiKey: LLM_TEST_KEY }));
    const out = await intentMod.classify({
      message: 'I want to stream movies', // regex: recommend
      history: [],
      deps: { credentialManager: cm, env: {}, fetchImpl: llmReplyFetch('{"intent":"deploy","appId":"jellyfin","reply":"Jellyfin streams movies"}'), log: silentLog, timeoutMs: 5000 },
    });
    expect(out.intent).toBe('deploy');
    expect(out.appId).toBe('jellyfin');
    const enriched = intentMod.enrich({ ...out });
    expect(enriched.response.message).toBeTruthy();
    expect(enriched.response.appId).toBe('jellyfin');
    expect(enriched.deployPlan.templateId).toBe('jellyfin');
    expect(enriched.deployPlan.body.port).toBe(8096); // real template defaultPort, not null
  });
});

// ─── HTTP surface ────────────────────────────────────────────────────────────
function buildRouter({ credentialManager = fakeCredStore(undefined), env = {}, fetchImpl = null } = {}) {
  jest.resetModules();
  const mod = require('../../routes/ai-intent');
  const asyncHandler = (fn) => async (req, res, next) => {
    try { await fn(req, res, next); } catch (e) { next(e); }
  };
  const errorResponse = (res, code, msg, extra) => res.status(code).json({ success: false, error: msg, ...(extra || {}) });

  const app = express();
  app.use(express.json());
  app.use('/api/v1', mod({ asyncHandler, errorResponse, log: silentLog, siteConfig: null, credentialManager, fetchImpl, env }));
  app.use((err, req, res, next) => { res.status(err.statusCode || 500).json({ success: false, error: err.message }); }); // eslint-disable-line no-unused-vars
  return app;
}

async function start(app) {
  const server = await new Promise((resolve) => {
    const s = app.listen(0, '127.0.0.1', () => resolve(s));
  });
  return { server, base: `http://127.0.0.1:${server.address().port}/api/v1` };
}

describe('DC-163 ai HTTP routes', () => {
  test('POST /ai/intent — flat ok() envelope (no data.data wrapper)', async () => {
    const app = buildRouter();
    const { server, base } = await start(app);
    try {
      const res = await fetch(`${base}/ai/intent`, {
        method: 'POST', headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ message: 'Deploy Plex' }),
      });
      const body = await res.json();
      expect(res.status).toBe(200);
      expect(body.success).toBe(true);
      expect(body.intent).toBe('deploy');
      expect(body.engine).toBe('pattern');
      expect(body.response.message).toBeTruthy();
      expect(body.response.appId).toBe('plex');
      expect(body.deployPlan.body.name).toBe('Plex');
      expect(body.timestamp).toBeTruthy();
    } finally { server.close(); }
  });

  test('POST /ai/intent — 400 on missing/non-string message', async () => {
    const app = buildRouter();
    const { server, base } = await start(app);
    try {
      for (const bad of [{}, { message: '' }, { message: 42 }, { message: '   '}]) {
        const res = await fetch(`${base}/ai/intent`, { method: 'POST', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify(bad) });
        expect(res.status).toBe(400);
      }
    } finally { server.close(); }
  });

  test('POST /ai/intent — message over 1000 chars is truncated, not rejected', async () => {
    const app = buildRouter();
    const { server, base } = await start(app);
    try {
      const res = await fetch(`${base}/ai/intent`, {
        method: 'POST', headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ message: 'Deploy Plex ' + 'z'.repeat(1500) }),
      });
      expect(res.status).toBe(200);
      const body = await res.json();
      expect(body.message.length).toBeLessThanOrEqual(1000);
      expect(body.intent).toBe('deploy');
    } finally { server.close(); }
  });

  test('GET /ai/settings — reports configuration WITHOUT the api key', async () => {
    const cm = fakeCredStore(JSON.stringify({ baseUrl: 'http://llm.test/v1', apiKey: LLM_TEST_KEY, model: 'test-model' }));
    const app = buildRouter({ credentialManager: cm });
    const { server, base } = await start(app);
    try {
      const res = await fetch(`${base}/ai/settings`);
      const body = await res.json();
      expect(body.success).toBe(true);
      expect(body.configured).toBe(true);
      expect(body.source).toBe('credential-store');
      expect(body.model).toBe('test-model');
      const raw = JSON.stringify(body);
      expect(raw).not.toContain(LLM_TEST_KEY);
      expect(body.hasApiKey).toBe(true);
    } finally { server.close(); }
  });

  test('PUT /ai/settings — stores in credential store; requires baseUrl+apiKey on first save', async () => {
    const cm = fakeCredStore(undefined);
    const app = buildRouter({ credentialManager: cm });
    const { server, base } = await start(app);
    try {
      // missing key → 400
      const r1 = await fetch(`${base}/ai/settings`, { method: 'PUT', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify({ baseUrl: 'http://llm.test/v1' }) });
      expect(r1.status).toBe(400);
      // bad baseUrl → 400
      const r2 = await fetch(`${base}/ai/settings`, { method: 'PUT', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify({ baseUrl: 'ftp://x', apiKey: LLM_TEST_KEY }) });
      expect(r2.status).toBe(400);
      // valid → stored encrypted (credentialManager.store), response never echoes key
      const r3 = await fetch(`${base}/ai/settings`, { method: 'PUT', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify({ baseUrl: 'http://llm.test/v1', model: 'test-model', apiKey: LLM_TEST_KEY }) });
      const b3 = await r3.json();
      expect(r3.status).toBe(200);
      expect(b3.saved).toBe(true);
      expect(JSON.stringify(b3)).not.toContain(LLM_TEST_KEY);
      const stored = JSON.parse(cm._store.get('ai:llm'));
      expect(stored.apiKey).toBe(LLM_TEST_KEY);
      // partial update keeps stored key
      const r4 = await fetch(`${base}/ai/settings`, { method: 'PUT', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify({ model: 'new-model' }) });
      expect(r4.status).toBe(200);
      expect(JSON.parse(cm._store.get('ai:llm')).apiKey).toBe(LLM_TEST_KEY);
      expect(JSON.parse(cm._store.get('ai:llm')).model).toBe('new-model');
    } finally { server.close(); }
  });

  test('DELETE /ai/settings — clears stored config', async () => {
    const cm = fakeCredStore(JSON.stringify({ baseUrl: 'http://llm.test/v1', apiKey: LLM_TEST_KEY }));
    const app = buildRouter({ credentialManager: cm });
    const { server, base } = await start(app);
    try {
      const res = await fetch(`${base}/ai/settings`, { method: 'DELETE' });
      expect(res.status).toBe(200);
      expect(cm._store.has('ai:llm')).toBe(false);
      const after = await (await fetch(`${base}/ai/settings`)).json();
      expect(after.configured).toBe(false);
    } finally { server.close(); }
  });

  test('POST /ai/settings/test — end-to-end probe returns sample intent, no key', async () => {
    const cm = fakeCredStore(JSON.stringify({ baseUrl: 'http://llm.test/v1', apiKey: LLM_TEST_KEY, model: 'test-model' }));
    const fetchImpl = llmReplyFetch('{"intent":"backup","appId":null,"reply":"Backup it is"}');
    const app = buildRouter({ credentialManager: cm, fetchImpl });
    const { server, base } = await start(app);
    try {
      const res = await fetch(`${base}/ai/settings/test`, { method: 'POST', headers: { 'Content-Type': 'application/json' }, body: '{}' });
      const body = await res.json();
      expect(body.ok).toBe(true);
      expect(body.engine).toBe('llm');
      expect(body.sample.intent).toBe('backup');
      expect(JSON.stringify(body)).not.toContain(LLM_TEST_KEY);
    } finally { server.close(); }
  });

  test('POST /ai/settings/test — failure degrades to ok:false with reason (never throws)', async () => {
    const cm = fakeCredStore(JSON.stringify({ baseUrl: 'http://llm.test/v1', apiKey: LLM_TEST_KEY }));
    const app = buildRouter({ credentialManager: cm, fetchImpl: async () => { throw new Error('ECONNREFUSED'); } });
    const { server, base } = await start(app);
    try {
      const res = await fetch(`${base}/ai/settings/test`, { method: 'POST', headers: { 'Content-Type': 'application/json' }, body: '{}' });
      expect(res.status).toBe(200);
      const body = await res.json();
      expect(body.ok).toBe(false);
      expect(body.reason).toMatch(/ECONNREFUSED/);
    } finally { server.close(); }
  });

  test('POST /ai/settings/test — sample MUST classify as backup; coerced unknown = failure', async () => {
    // Judge r1 blocker #2: accepting a coerced 'unknown' would let a model
    // that ignores our prompt "pass" the test. Strict expectation now.
    const cm = fakeCredStore(JSON.stringify({ baseUrl: 'http://llm.test/v1', apiKey: LLM_TEST_KEY, model: 'test-model' }));
    const fetchImpl = llmReplyFetch('{"intent":"chitchat","appId":null,"reply":"lol sure"}'); // illegal -> coerces to unknown
    const app = buildRouter({ credentialManager: cm, fetchImpl });
    const { server, base } = await start(app);
    try {
      const res = await fetch(`${base}/ai/settings/test`, { method: 'POST', headers: { 'Content-Type': 'application/json' }, body: '{}' });
      const body = await res.json();
      expect(res.status).toBe(200);
      expect(body.ok).toBe(false);
      expect(body.engine).toBe('llm-error');
      expect(body.reason).toMatch(/expected 'backup', got 'unknown'/);
    } finally { server.close(); }
  });

  test('GET /ai/capabilities — engine reflects live configuration', async () => {
    const app = buildRouter();
    const { server, base } = await start(app);
    try {
      const body = await (await fetch(`${base}/ai/capabilities`)).json();
      expect(body.success).toBe(true);
      expect(body.engine).toBe('pattern');
      expect(body.llm.configured).toBe(false);
      expect(body.llm.howToEnable).toMatch(/credential store/);
      expect(body.intents).toContain('deploy');
      expect(body.capabilities.length).toBeGreaterThanOrEqual(6);
    } finally { server.close(); }
  });
});