import { formatCurrency, validateStep } from '../utils';
import { EMPTY_FORM_DATA, VALID_STEP1_DATA, VALID_STEP2_DATA } from './helpers';
import { FormData } from '../types';

describe('formatCurrency', () => {
  it('should format 0 as £0', () => {
    expect(formatCurrency(0)).toBe('£0');
  });

  it('should format large numbers with comma separators', () => {
    expect(formatCurrency(50000)).toBe('£50,000');
  });

  it('should format mid-range numbers', () => {
    expect(formatCurrency(1500)).toBe('£1,500');
  });
});

describe('validateStep', () => {
  describe('step 1 - personal details', () => {
    it('should return errors for all empty fields', () => {
      const result = validateStep(1, EMPTY_FORM_DATA);
      expect(result.isValid).toBe(false);
      expect(result.errors.firstName).toBeDefined();
      expect(result.errors.lastName).toBeDefined();
      expect(result.errors.telephone).toBeDefined();
      expect(result.errors.email).toBeDefined();
    });

    it('should pass with valid data', () => {
      const data: FormData = { ...EMPTY_FORM_DATA, ...VALID_STEP1_DATA };
      const result = validateStep(1, data);
      expect(result.isValid).toBe(true);
      expect(Object.keys(result.errors)).toHaveLength(0);
    });

    it('should return error for invalid email', () => {
      const data: FormData = {
        ...EMPTY_FORM_DATA,
        ...VALID_STEP1_DATA,
        email: 'not-an-email'
      };
      const result = validateStep(1, data);
      expect(result.isValid).toBe(false);
      expect(result.errors.email).toBe('Please enter a valid email address');
    });

    it('should return error for invalid phone', () => {
      const data: FormData = {
        ...EMPTY_FORM_DATA,
        ...VALID_STEP1_DATA,
        telephone: 'abc'
      };
      const result = validateStep(1, data);
      expect(result.isValid).toBe(false);
      expect(result.errors.telephone).toBe(
        'Please enter a valid telephone number'
      );
    });

    it('should trim whitespace-only fields', () => {
      const data: FormData = {
        ...EMPTY_FORM_DATA,
        firstName: '   ',
        lastName: '  '
      };
      const result = validateStep(1, data);
      expect(result.isValid).toBe(false);
      expect(result.errors.firstName).toBeDefined();
      expect(result.errors.lastName).toBeDefined();
    });
  });

  describe('step 2 - trip details', () => {
    it('should return errors for all empty fields', () => {
      const result = validateStep(2, EMPTY_FORM_DATA);
      expect(result.isValid).toBe(false);
      expect(result.errors.departurePort).toBeDefined();
      expect(result.errors.destination).toBeDefined();
      expect(result.errors.month).toBeDefined();
      expect(result.errors.year).toBeDefined();
      expect(result.errors.duration).toBeDefined();
      expect(result.errors.adults).toBeDefined();
      expect(result.errors.children).toBeDefined();
    });

    it('should pass with valid data', () => {
      const data: FormData = { ...EMPTY_FORM_DATA, ...VALID_STEP2_DATA };
      const result = validateStep(2, data);
      expect(result.isValid).toBe(true);
      expect(Object.keys(result.errors)).toHaveLength(0);
    });
  });

  describe('step 3 - budget & extras', () => {
    it('should always pass (no required fields)', () => {
      const result = validateStep(3, EMPTY_FORM_DATA);
      expect(result.isValid).toBe(true);
      expect(Object.keys(result.errors)).toHaveLength(0);
    });
  });

  describe('unknown step', () => {
    it('should return valid for an unknown step number', () => {
      const result = validateStep(99, EMPTY_FORM_DATA);
      expect(result.isValid).toBe(true);
    });
  });
});