import assert from 'node:assert/strict';
import fs from 'node:fs';
import path from 'node:path';
import test from 'node:test';
import {
  createConnectivityDiagnosticsService,
  CURL_META_MARKER,
} from '../../dist/server/services/connectivityDiagnosticsService.js';
import { createConnectivityDiagnosticsUseCase } from '../../dist/server/features/diagnostics/index.js';
import { createConnectivityDiagnosticsRoute } from '../../dist/server/http/routes/connectivityDiagnosticsRoute.js';

const server = fs.readFileSync(path.resolve(import.meta.dirname, '../../src/server/index.ts'), 'utf8');

function response(body = '', overrides = {}) {
  return {
    exitCode: 0,
    error: '',
    stderr: '',
    stdout: `${body}${CURL_META_MARKER}${JSON.stringify({
      exitcode: 0,
      http_code: 204,
      time_starttransfer: 0.12,
      time_total: 0.15,
      ...overrides,
    })}`,
  };
}

test('connectivity diagnostics force separate direct and VPN paths', async () => {
  const calls = [];
  const execute = async (args) => {
    calls.push(args);
    const vpn = args.includes('--proxy');
    const url = args.at(-1);
    if (url.includes('cloudflare')) return response(`ip=${vpn ? '203.0.113.20' : '198.51.100.10'}\n`);
    if (url.includes('api6')) return response(vpn ? '2001:db8::20' : '2001:db8::10');
    if (url.includes('ipify')) return response(vpn ? '203.0.113.20' : '198.51.100.10');
    return response();
  };
  const service = createConnectivityDiagnosticsService({
    proxyPort: 18080,
    execute,
    now: () => '2026-08-07T12:00:00.000Z',
  });

  const result = await service.run({ vpnAvailable: true });

  assert.deepEqual(result.direct.ipv4.addresses, ['198.51.100.10']);
  assert.deepEqual(result.vpn.ipv4.addresses, ['203.0.113.20']);
  assert.equal(result.direct.ipv6, '2001:db8::10');
  assert.equal(result.vpn.ipv6, '2001:db8::20');
  assert.equal(result.assessment.summary, 'available');
  assert.ok(calls.some((args) => args.includes('--noproxy') && args.includes('*')));
  assert.ok(calls.some((args) => args.includes('--proxy') && args.includes('http://127.0.0.1:18080')));
});

test('connectivity diagnostics endpoint is available in Connect and Gateway through one owner', () => {
  assert.match(server, /const localConnectivityDiagnostics = !remoteDataplane/);
  assert.doesNotMatch(server, /settings\.appMode !== 'gateway'[\s\S]{0,120}ENDPOINT_NOT_FOUND/);
  assert.match(server, /runConnectivityDiagnostics\(services, target\)/);
  assert.match(server, /createConnectivityDiagnosticsUseCase\(\{/);
  assert.match(server, /createConnectivityDiagnosticsRoute\(\{/);
  assert.match(server, /connectivityDiagnosticsRoute\.handle\(req, res\)/);
  assert.doesNotMatch(server, /['"]\/api\/diagnostics\/connectivity['"]/);
  assert.doesNotMatch(server, /appliedServerId\s*\|\|\s*state\.selectedServerId/);
});

test('connectivity use case captures applied server before probes and preserves result fields', async () => {
  const events = [];
  let state = {
    desiredProfileId: 'primary',
    appliedProfileId: 'primary',
    appliedServerId: 'applied',
    profiles: [{
      id: 'primary',
      desiredServerId: 'selected',
      servers: [
        { id: 'applied', label: 'Applied before probe' },
        { id: 'selected', label: 'Selected' },
      ],
    }],
  };
  let releaseProbe;
  const probe = new Promise((resolve) => { releaseProbe = resolve; });
  const sourceResult = {
    checkedAt: 'now',
    direct: { available: true },
    vpn: { available: true, server: { id: 'stale', label: 'Stale' }, detail: 7 },
    assessment: { summary: 'available' },
  };
  const useCase = createConnectivityDiagnosticsUseCase({
    readState: () => {
      events.push('state');
      return state;
    },
    runDiagnostics: async (services, target) => {
      events.push(['probe', services, target]);
      await probe;
      return sourceResult;
    },
  });
  const resultPromise = useCase.run({ raw: true }, 42);
  state.profiles[0].servers[0].label = 'Changed during probe';
  releaseProbe();
  const result = await resultPromise;

  assert.deepEqual(events, ['state', ['probe', { raw: true }, 42]]);
  assert.deepEqual(result, {
    ...sourceResult,
    vpn: {
      ...sourceResult.vpn,
      server: { id: 'applied', label: 'Applied before probe' },
    },
  });
  assert.deepEqual(sourceResult.vpn.server, { id: 'stale', label: 'Stale' });
});

test('connectivity use case keeps applied priority, selected fallback and error identity', async () => {
  const result = { vpn: { available: false }, marker: true };
  const selected = createConnectivityDiagnosticsUseCase({
    readState: () => ({
      desiredProfileId: 'primary',
      appliedServerId: '',
      profiles: [{
        id: 'primary',
        desiredServerId: 'selected',
        servers: [{ id: 'selected', label: 'Selected' }],
      }],
    }),
    runDiagnostics: async () => result,
  });
  assert.deepEqual((await selected.run(null, null)).vpn.server, {
    id: 'selected',
    label: 'Selected',
  });

  const missingApplied = createConnectivityDiagnosticsUseCase({
    readState: () => ({
      desiredProfileId: 'primary',
      appliedProfileId: 'primary',
      appliedServerId: 'missing',
      profiles: [{
        id: 'primary',
        desiredServerId: 'selected',
        servers: [{ id: 'selected', label: 'Selected' }],
      }],
    }),
    runDiagnostics: async () => result,
  });
  assert.equal((await missingApplied.run([], null)).vpn.server, null);

  const stateError = new Error('state failed');
  let probes = 0;
  const brokenState = createConnectivityDiagnosticsUseCase({
    readState: () => { throw stateError; },
    runDiagnostics: async () => { probes += 1; return result; },
  });
  await assert.rejects(brokenState.run([], null), (error) => error === stateError);
  assert.equal(probes, 0);

  const probeError = new Error('probe failed');
  const brokenProbe = createConnectivityDiagnosticsUseCase({
    readState: () => ({ servers: [] }),
    runDiagnostics: async () => { throw probeError; },
  });
  await assert.rejects(brokenProbe.run([], null), (error) => error === probeError);
});

function routeResponse() {
  return {
    writeHead(status, headers) {
      this.status = status;
      this.headers = headers;
    },
    end(payload) {
      this.payload = JSON.parse(payload);
    },
  };
}

test('connectivity route preserves exact URL, defaults and raw response', async () => {
  const calls = [];
  let body = {};
  let bodyReads = 0;
  const route = createConnectivityDiagnosticsRoute({
    diagnostics: {
      run: async (...args) => {
        calls.push(args);
        return { checkedAt: 'now', vpn: { server: null } };
      },
    },
    readBody: async () => {
      bodyReads += 1;
      return body;
    },
  });
  const res = routeResponse();
  assert.equal(await route.handle({
    method: 'POST',
    url: '/api/diagnostics/connectivity',
  }, res), true);
  assert.deepEqual(calls, [[[], null]]);
  assert.equal(res.status, 200);
  assert.equal(res.headers['content-type'], 'application/json; charset=utf-8');
  assert.deepEqual(res.payload, { checkedAt: 'now', vpn: { server: null } });

  body = { services: null, target: 17 };
  await route.handle({ method: 'POST', url: '/api/diagnostics/connectivity' }, routeResponse());
  assert.deepEqual(calls.at(-1), [null, 17]);

  for (const [method, url] of [
    ['GET', '/api/diagnostics/connectivity'],
    ['POST', '/api/diagnostics/connectivity?target=all'],
    ['POST', '/api/diagnostics/other'],
  ]) {
    assert.equal(await route.handle({ method, url }, routeResponse()), false);
  }
  assert.equal(bodyReads, 2);
});

test('a targeted IP row uses three samples and keeps the majority address', async () => {
  const attempts = { direct: 0, vpn: 0 };
  const execute = async (args) => {
    const route = args.includes('--proxy') ? 'vpn' : 'direct';
    attempts[route] += 1;
    if (route === 'vpn' && attempts.vpn === 1) {
      return response('', { exitcode: 28, http_code: 0, errormsg: 'timeout' });
    }
    const address = route === 'vpn' ? '203.0.113.20' : '198.51.100.10';
    return response(`{"ipv4":"${address}"}`, {
      time_starttransfer: route === 'vpn' ? attempts.vpn * 0.1 : attempts.direct * 0.1,
    });
  };
  const result = await createConnectivityDiagnosticsService({ proxyPort: 18080, execute })
    .run({ vpnAvailable: true, target: 'ip:yandex-internet' });

  assert.equal(result.direct.ipv4.sources[0].attempts, 3);
  assert.equal(result.vpn.ipv4.sources[0].attempts, 3);
  assert.equal(result.direct.ipv4.sources[0].address, '198.51.100.10');
  assert.equal(result.vpn.ipv4.sources[0].address, '203.0.113.20');
  assert.equal(result.direct.ipv4.sources[0].latencyMs, 200);
  assert.equal(result.vpn.ipv4.sources[0].latencyMs, 250);
});

test('a targeted service row averages three measurements and ignores one transient failure', async () => {
  const attempts = { direct: 0, vpn: 0 };
  const execute = async (args) => {
    const route = args.includes('--proxy') ? 'vpn' : 'direct';
    attempts[route] += 1;
    if (route === 'direct' && attempts.direct === 1) {
      return response('', { exitcode: 28, http_code: 0, errormsg: 'timeout' });
    }
    return response('', {
      time_starttransfer: route === 'direct' ? attempts.direct * 0.1 : attempts.vpn * 0.2,
    });
  };
  const result = await createConnectivityDiagnosticsService({ proxyPort: 18080, execute })
    .run({ vpnAvailable: true, target: 'site:yandex' });

  assert.deepEqual(attempts, { direct: 3, vpn: 3 });
  assert.equal(result.direct.sites[0].status, 'available');
  assert.equal(result.direct.sites[0].attempts, 3);
  assert.equal(result.direct.sites[0].latencyMs, 250);
  assert.equal(result.vpn.sites[0].latencyMs, 400);
});

test('connectivity diagnostics reports a likely direct restriction without claiming its owner', async () => {
  const attempts = new Map();
  const execute = async (args) => {
    const vpn = args.includes('--proxy');
    const url = args.at(-1);
    if (url.includes('cloudflare')) return response(`ip=${vpn ? '203.0.113.20' : '198.51.100.10'}\n`);
    if (url.includes('api6')) return response('', { exitcode: 6, http_code: 0, errormsg: 'resolve failed' });
    if (url.includes('ipify')) return response(vpn ? '203.0.113.20' : '198.51.100.10');
    const key = `${vpn}:${url}`;
    attempts.set(key, (attempts.get(key) || 0) + 1);
    if (!vpn && url.includes('youtube')) {
      return response('', { exitcode: 28, http_code: 0, errormsg: 'timeout' });
    }
    return response();
  };
  const result = await createConnectivityDiagnosticsService({ proxyPort: 18080, execute })
    .run({ vpnAvailable: true });

  assert.equal(result.assessment.summary, 'likely-direct-restriction');
  assert.equal(
    result.assessment.comparisons.find((item) => item.id === 'youtube').assessment,
    'likely-direct-restriction',
  );
  assert.equal(attempts.get('false:https://www.youtube.com/generate_204'), 2);
});

test('connectivity diagnostics skips VPN probes when sing-box is off', async () => {
  const calls = [];
  const execute = async (args) => {
    calls.push(args);
    const url = args.at(-1);
    if (url.includes('cloudflare')) return response('ip=198.51.100.10\n');
    if (url.includes('api6')) return response('', { exitcode: 6, http_code: 0, errormsg: 'resolve failed' });
    if (url.includes('ipify')) return response('198.51.100.10');
    return response();
  };
  const result = await createConnectivityDiagnosticsService({ proxyPort: 18080, execute })
    .run({ vpnAvailable: false });

  assert.equal(result.vpn.available, false);
  assert.equal(result.assessment.summary, 'vpn-off');
  assert.equal(calls.some((args) => args.includes('--proxy')), false);
});

test('connectivity diagnostics keeps every IP source in a partial snapshot', async () => {
  const execute = async (args) => {
    const url = args.at(-1);
    if (url.includes('cloudflare')) {
      return response('', { exitcode: 28, http_code: 0, errormsg: 'timeout' });
    }
    if (url.includes('api6')) return response('', { exitcode: 6, http_code: 0, errormsg: 'resolve failed' });
    if (url.includes('ipify')) return response('198.51.100.10');
    if (url.includes('amazonaws')) return response('198.51.100.10');
    return response();
  };
  const result = await createConnectivityDiagnosticsService({ proxyPort: 18080, execute })
    .run({ vpnAvailable: false });

  assert.equal(result.direct.internetAvailable, true);
  assert.deepEqual(result.direct.ipv4.addresses, ['198.51.100.10']);
  assert.deepEqual(result.direct.ipv4.sources.map((source) => source.source), [
    'cloudflare',
    'ipify',
    'aws',
    'icanhazip',
    'ifconfig-me',
    'yandex-internet',
  ]);
});

test('connectivity diagnostics pins public custom services and rejects private destinations', async () => {
  const calls = [];
  const execute = async (args) => {
    calls.push(args);
    const url = args.at(-1);
    if (url.includes('cloudflare')) return response('ip=198.51.100.10\n');
    if (url.includes('api6')) return response('', { exitcode: 6, http_code: 0, errormsg: 'resolve failed' });
    if (url.includes('ipify')) return response('198.51.100.10');
    return response();
  };
  const lookup = async (hostname) => hostname === 'router.local'
    ? [{ address: '192.168.50.1', family: 4 }]
    : [{ address: '93.184.216.34', family: 4 }];
  const result = await createConnectivityDiagnosticsService({ proxyPort: 18080, execute, lookup })
    .run({
      vpnAvailable: false,
      services: [
        { id: 'custom-public', label: 'Example', url: 'https://example.com/status' },
        { id: 'custom-private', label: 'Router', url: 'https://router.local/' },
      ],
    });

  const publicCall = calls.find((args) => args.at(-1) === 'https://example.com/status');
  assert.ok(publicCall);
  assert.equal(publicCall.includes('--location'), false);
  assert.deepEqual(publicCall.slice(publicCall.indexOf('--resolve'), publicCall.indexOf('--resolve') + 2), [
    '--resolve',
    'example.com:443:93.184.216.34',
  ]);
  assert.equal(calls.some((args) => args.at(-1) === 'https://router.local/'), false);
  assert.equal(result.direct.sites.find((site) => site.id === 'custom-private').stage, 'validation');
  assert.equal(result.assessment.comparisons.some((item) => item.id === 'custom-public'), true);
});

test('a targeted custom row validates and samples only that service', async () => {
  const lookups = [];
  const calls = [];
  const result = await createConnectivityDiagnosticsService({
    proxyPort: 18080,
    execute: async (args) => {
      calls.push(args.at(-1));
      return response();
    },
    lookup: async (hostname) => {
      lookups.push(hostname);
      return [{ address: '93.184.216.34', family: 4 }];
    },
  }).run({
    vpnAvailable: false,
    services: [
      { id: 'custom-first', url: 'https://first.example/' },
      { id: 'custom-second', url: 'https://second.example/' },
    ],
    target: 'site:custom-second',
  });

  assert.deepEqual(lookups, ['second.example']);
  assert.deepEqual(calls, ['https://second.example/', 'https://second.example/', 'https://second.example/']);
  assert.equal(result.direct.sites[0].latencyMs, 120);
});