var moment = require('moment'); // require
  const { faker } = require('@faker-js/faker');
  const Ajv = require("ajv")
  var validator = require('validator');
  const base64 = require('base64-js');
  const jwt = require('jsonwebtoken');
  const { v4: uuidv4 } = require('uuid');
  const _ = require('lodash');
 
  function testLodash() {
    // Test data
    const users = [
      { id: 1, name: 'Alice', age: 25, active: true },
      { id: 2, name: 'Bob', age: 30, active: false },
      { id: 3, name: 'Charlie', age: 35, active: true },
      { id: 4, name: 'David', age: 40, active: false }
    ];
 
    // Example 1: Filter active users
    const activeUsers = _.filter(users, { active: true });
    console.log('Active Users:', activeUsers);
 
    // Example 2: Sort users by age in descending order
    const sortedByAge = _.orderBy(users, ['age'], ['desc']);
    console.log('Users sorted by age (desc):', sortedByAge);
 
    // Example 3: Get the names of all users
    const userNames = _.map(users, 'name');
    console.log('User Names:', userNames);
  }
 
  function testMoment() {
    console.log("current time is:", moment().format());
  }
 
  function testUuidv4() {
    console.log("uuid is:", uuidv4());
  }
 
  function testAjv() {
    const ajv = new Ajv() // options can be passed, e.g. {allErrors: true}
 
    const schema = {
      type: "object",
      properties: {
        foo: { type: "integer" },
        bar: { type: "string" },
      },
      required: ["foo"],
      additionalProperties: false,
    }
 
    const data = {
      foo: true,
      bar: "abc",
    }
 
    const validate = ajv.compile(schema)
    const valid = validate(data)
    if (!valid) console.log(validate.errors)
  }
 
  function testBase64() {
    // Example 1: Encode a string to Base64
    const text = 'Hello, world!';
    const textBytes = new TextEncoder().encode(text); // Convert string to Uint8Array
    const base64Encoded = base64.fromByteArray(textBytes); // Encode to Base64
    console.log('Base64 Encoded:', base64Encoded);
 
    // Example 2: Decode a Base64 string back to its original format
    const decodedBytes = base64.toByteArray(base64Encoded); // Decode to Uint8Array
    const decodedText = new TextDecoder().decode(decodedBytes); // Convert Uint8Array to string
    console.log('Decoded Text:', decodedText);
  }
 
  function testValidator() {
    const result = validator.isEmail('fooo~bar.com');
    console.log("fooo~bar.com is email, right?", result);
  }
 
  function testFakerJS() {
    return {
      userId: faker.string.uuid(),
      username: faker.internet.username(), // before version 9.1.0, use userName()
      email: faker.internet.email(),
      avatar: faker.image.avatar(),
      password: faker.internet.password(),
      birthdate: faker.date.birthdate(),
      registeredAt: faker.date.past(),
    };
  }
 
  function testJwt() {
    // Secret key for signing the token
    const SECRET_KEY = 'your-secret-key';
 
    // Sample payload
    const payload = { userId: 123, username: 'testUser' };
 
    // Create a token
    const token = jwt.sign(payload, SECRET_KEY, { expiresIn: '1h' });
    console.log('Generated Token:', token);
 
    // Verify the token
    try {
      const decoded = jwt.verify(token, SECRET_KEY);
      console.log('Decoded Payload:', decoded);
    } catch (err) {
      console.error('Token verification failed:', err.message);
    }
  }
 
  mock.get("/testlibs", (req, res) => {
    console.log("==== this is a test of libs supported =====");
    testLodash();
    testMoment();
    testUuidv4();
    testAjv();
    testValidator();
    testBase64();
    testJwt();
 
    const jsonData = testFakerJS();
 
    return res.status(200).json(jsonData)
  });