// Simple Unit Tests for Core Functions
const bcrypt = require('bcrypt');
const jwt = require('jsonwebtoken');

// Mock external dependencies
jest.mock('bcrypt');
jest.mock('jsonwebtoken');

describe('Simple Unit Tests', () => {
  beforeEach(() => {
    jest.clearAllMocks();
  });

  describe('Password Hashing', () => {
    it('should hash password correctly', async () => {
      const password = 'testpassword';
      const hashedPassword = 'hashedpassword123';

      bcrypt.hash.mockResolvedValue(hashedPassword);

      const result = await bcrypt.hash(password, 10);

      expect(result).toBe(hashedPassword);
      expect(bcrypt.hash).toHaveBeenCalledWith(password, 10);
    });

    it('should compare password correctly', async () => {
      const password = 'testpassword';
      const hashedPassword = 'hashedpassword123';

      bcrypt.compare.mockResolvedValue(true);

      const result = await bcrypt.compare(password, hashedPassword);

      expect(result).toBe(true);
      expect(bcrypt.compare).toHaveBeenCalledWith(password, hashedPassword);
    });
  });

  describe('JWT Token', () => {
    it('should generate JWT token', () => {
      const payload = { userId: 'user123' };
      const token = 'mock.jwt.token';

      jwt.sign.mockReturnValue(token);

      const result = jwt.sign(payload, 'secret', { expiresIn: '7d' });

      expect(result).toBe(token);
      expect(jwt.sign).toHaveBeenCalledWith(payload, 'secret', {
        expiresIn: '7d',
      });
    });

    it('should verify JWT token', () => {
      const token = 'mock.jwt.token';
      const decoded = { userId: 'user123' };

      jwt.verify.mockReturnValue(decoded);

      const result = jwt.verify(token, 'secret');

      expect(result).toEqual(decoded);
      expect(jwt.verify).toHaveBeenCalledWith(token, 'secret');
    });
  });

  describe('Utility Functions', () => {
    it('should validate email format', () => {
      const validateEmail = (email) => {
        const emailRegex = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
        return emailRegex.test(email);
      };

      expect(validateEmail('test@example.com')).toBe(true);
      expect(validateEmail('invalid-email')).toBe(false);
      expect(validateEmail('test@')).toBe(false);
    });

    it('should validate phone number format', () => {
      const validatePhone = (phone) => {
        const phoneRegex = /^[0-9]{10}$/;
        return phoneRegex.test(phone);
      };

      expect(validatePhone('1234567890')).toBe(true);
      expect(validatePhone('123456789')).toBe(false);
      expect(validatePhone('12345678901')).toBe(false);
      expect(validatePhone('123456789a')).toBe(false);
    });

    it('should validate password strength', () => {
      const { validatePassword } = require('../../Utils/passwordUtils');

      // Valid passwords with uppercase, lowercase, number, and special char
      expect(validatePassword('Password123!')).toBe(true);
      expect(validatePassword('Valid@Pass1')).toBe(true);
      
      // Invalid passwords
      expect(validatePassword('pass')).toBe(false);
      expect(validatePassword('')).toBe(false);
      expect(validatePassword(null)).toBe(false);
      expect(validatePassword(undefined)).toBe(false);
    });

    it('should validate name format', () => {
      const validateName = (name) => {
        return Boolean(name && name.trim().length >= 2);
      };

      expect(validateName('John')).toBe(true);
      expect(validateName('A')).toBe(false);
      expect(validateName('')).toBe(false);
      expect(validateName('   ')).toBe(false);
      expect(validateName(null)).toBe(false);
      expect(validateName(undefined)).toBe(false);
    });
  });

  describe('Date and Time Functions', () => {
    it('should check if date is in the future', () => {
      const isFutureDate = (date) => {
        return new Date(date) > new Date();
      };

      const futureDate = new Date();
      futureDate.setDate(futureDate.getDate() + 1);

      const pastDate = new Date();
      pastDate.setDate(pastDate.getDate() - 1);

      expect(isFutureDate(futureDate)).toBe(true);
      expect(isFutureDate(pastDate)).toBe(false);
    });

    it('should format date correctly', () => {
      const formatDate = (date) => {
        return new Date(date).toISOString().split('T')[0];
      };

      const testDate = new Date('2024-01-15');
      expect(formatDate(testDate)).toBe('2024-01-15');
    });
  });

  describe('String Manipulation', () => {
    it('should capitalize first letter', () => {
      const capitalize = (str) => {
        return str.charAt(0).toUpperCase() + str.slice(1);
      };

      expect(capitalize('hello')).toBe('Hello');
      expect(capitalize('world')).toBe('World');
      expect(capitalize('')).toBe('');
    });

    it('should truncate long strings', () => {
      const truncate = (str, length) => {
        return str.length > length ? `${str.substring(0, length)}...` : str;
      };

      expect(truncate('Hello World', 5)).toBe('Hello...');
      expect(truncate('Short', 10)).toBe('Short');
    });
  });

  describe('Array Operations', () => {
    it('should remove duplicates from array', () => {
      const removeDuplicates = (arr) => {
        return [...new Set(arr)];
      };

      expect(removeDuplicates([1, 2, 2, 3, 3, 4])).toEqual([1, 2, 3, 4]);
      expect(removeDuplicates(['a', 'b', 'a', 'c'])).toEqual(['a', 'b', 'c']);
    });

    it('should find unique values', () => {
      const findUnique = (arr) => {
        return arr.filter((item, index) => arr.indexOf(item) === index);
      };

      expect(findUnique([1, 2, 2, 3, 3, 4])).toEqual([1, 2, 3, 4]);
    });
  });

  describe('Object Operations', () => {
    it('should merge objects', () => {
      const mergeObjects = (obj1, obj2) => {
        return { ...obj1, ...obj2 };
      };

      const obj1 = { a: 1, b: 2 };
      const obj2 = { b: 3, c: 4 };

      expect(mergeObjects(obj1, obj2)).toEqual({ a: 1, b: 3, c: 4 });
    });

    it('should remove null/undefined values', () => {
      const removeNullValues = (obj) => {
        return Object.fromEntries(
          Object.entries(obj).filter(([_, value]) => value != null),
        );
      };

      const testObj = { a: 1, b: null, c: undefined, d: 2 };
      expect(removeNullValues(testObj)).toEqual({ a: 1, d: 2 });
    });
  });
});