const assert = require('node:assert/strict');
const test = require('node:test');

const {
  ALERT_TITLE_FALLBACKS,
  AlertNotificationService,
  buildAlertCreatedMessage
} = require('../src/services/alertNotificationService');
const { createFirebaseMessaging, getFirebaseConfig } = require('../src/config/firebase');

function createLogger() {
  const errors = [];
  return {
    errors,
    error(message, metadata) {
      errors.push({ message, metadata });
    }
  };
}

test('sends an exact data-only alert-created message with string-only data', async () => {
  const messages = [];
  const service = new AlertNotificationService({
    enabled: true,
    topic: 'route_alerts',
    androidChannelId: 'route_alerts',
    messaging: {
      async send(message) {
        messages.push(message);
        return 'projects/test/messages/42';
      }
    },
    logger: createLogger()
  });

  const result = await service.sendAlertCreated({
    id: 42,
    route_id: 7,
    route_number: 12,
    alert_type: 'delay',
    title: 'Автобус задерживается',
    message: 'Задержка около 15 минут',
    start_time: new Date('2026-07-11T08:30:00.000Z'),
    end_time: '2026-07-11T09:30:00Z',
    is_active: true
  });

  assert.deepEqual(result, {
    sent: true,
    messageId: 'projects/test/messages/42'
  });
  assert.equal(messages.length, 1);
  assert.deepEqual(messages[0], {
    topic: 'route_alerts',
    data: {
      event: 'alert_created',
      alertId: '42',
      type: 'delay',
      routeId: '7',
      routeNumber: '12',
      startTime: '2026-07-11T08:30:00.000Z',
      endTime: '2026-07-11T09:30:00.000Z',
      title: 'Автобус задерживается',
      body: 'Задержка около 15 минут'
    },
    android: {
      priority: 'high'
    }
  });
  assert.equal('notification' in messages[0], false);
  assert.equal('notification' in messages[0].android, false);
  assert.equal(messages[0].android.priority, 'high');
  assert.equal(messages[0].data.title, 'Автобус задерживается');
  assert.equal(messages[0].data.body, 'Задержка около 15 минут');
  assert.ok(Object.values(messages[0].data).every((value) => typeof value === 'string'));
});

test('serializes a null route id and missing optional values as empty strings', () => {
  const message = buildAlertCreatedMessage({
    id: 9,
    route_id: null,
    route_number: null,
    alert_type: 'info',
    title: 'Новость',
    message: 'Важная информация',
    start_time: null,
    end_time: null
  });

  assert.equal(message.data.routeId, '');
  assert.equal(message.data.routeNumber, '');
  assert.equal(message.data.startTime, '');
  assert.equal(message.data.endTime, '');
  assert.equal(message.data.title, 'Новость');
  assert.equal(message.data.body, 'Важная информация');
  assert.equal('notification' in message, false);
  assert.equal('notification' in message.android, false);
});

test('does not initialize messaging or send for an inactive alert', async () => {
  let messagingInitializations = 0;
  const service = new AlertNotificationService({
    enabled: true,
    getMessaging() {
      messagingInitializations += 1;
      return { send: async () => 'unexpected' };
    },
    logger: createLogger()
  });

  const result = await service.sendAlertCreated({ id: 10, is_active: false });

  assert.deepEqual(result, { sent: false, skipped: true, reason: 'inactive' });
  assert.equal(messagingInitializations, 0);
});

test('disabled mode works without initializing Firebase or credentials', async () => {
  let messagingInitializations = 0;
  const service = new AlertNotificationService({
    enabled: false,
    getMessaging() {
      messagingInitializations += 1;
      throw new Error('credentials should not be read');
    },
    logger: createLogger()
  });

  const result = await service.sendAlertCreated({ id: 11, is_active: true });

  assert.deepEqual(result, { sent: false, skipped: true, reason: 'disabled' });
  assert.equal(messagingInitializations, 0);
});

test('logs Firebase failures with safe structured metadata and does not throw', async () => {
  const testLogger = createLogger();
  const firebaseError = Object.assign(new Error('Permission denied'), {
    code: 'messaging/authentication-error'
  });
  const service = new AlertNotificationService({
    enabled: true,
    messaging: {
      async send() {
        throw firebaseError;
      }
    },
    logger: testLogger
  });

  const result = await service.sendAlertCreated({
    id: 57,
    alert_type: 'detour',
    message: 'Объезд',
    is_active: true
  });

  assert.deepEqual(result, {
    sent: false,
    reason: 'fcm_error',
    firebaseCode: 'messaging/authentication-error'
  });
  assert.deepEqual(testLogger.errors, [{
    message: 'Failed to send alert-created FCM notification',
    metadata: {
      alertId: '57',
      reason: 'Permission denied',
      firebaseCode: 'messaging/authentication-error'
    }
  }]);
});

test('logs lazy Firebase initialization failures and does not throw', async () => {
  const testLogger = createLogger();
  const initializationError = Object.assign(new Error('Application default credentials unavailable'), {
    code: 'app/invalid-credential'
  });
  const service = new AlertNotificationService({
    enabled: true,
    getMessaging() {
      throw initializationError;
    },
    logger: testLogger
  });

  const result = await service.sendAlertCreated({
    id: 58,
    alert_type: 'info',
    message: 'Новость',
    is_active: true
  });

  assert.deepEqual(result, {
    sent: false,
    reason: 'fcm_error',
    firebaseCode: 'app/invalid-credential'
  });
  assert.deepEqual(testLogger.errors[0].metadata, {
    alertId: '58',
    reason: 'Application default credentials unavailable',
    firebaseCode: 'app/invalid-credential'
  });
});

test('uses the requested Russian title fallbacks and a route-aware body fallback', () => {
  for (const [type, expectedTitle] of Object.entries(ALERT_TITLE_FALLBACKS)) {
    const message = buildAlertCreatedMessage({
      id: 71,
      alert_type: type,
      title: '   ',
      message: '',
      route_number: '5'
    });

    assert.equal(message.data.title, expectedTitle);
    assert.equal(message.data.body, 'Актуальная информация по маршруту №5');
  }

  const withoutRoute = buildAlertCreatedMessage({
    id: 72,
    alert_type: 'info',
    title: '',
    message: ''
  });
  assert.equal(withoutRoute.data.body, 'Актуальная информация о движении транспорта');
});

test('reads disabled-by-default Firebase configuration and environment overrides', () => {
  assert.deepEqual(getFirebaseConfig({}), {
    enabled: false,
    topic: 'route_alerts',
    androidChannelId: 'route_alerts',
    projectId: undefined
  });
  assert.equal(createFirebaseMessaging(getFirebaseConfig({})), null);

  assert.deepEqual(getFirebaseConfig({
    FCM_ENABLED: 'true',
    FCM_TOPIC: 'custom_alerts',
    FCM_ANDROID_CHANNEL_ID: 'custom_channel',
    FIREBASE_PROJECT_ID: 'ridebus-test'
  }), {
    enabled: true,
    topic: 'custom_alerts',
    androidChannelId: 'custom_channel',
    projectId: 'ridebus-test'
  });
});