import { describe, it, expect } from 'vitest';
import {
  DomainService,
  DomainCalculationService,
  ResultDomainCalculationService,
  DomainValidationService,
  DomainFactoryService,
  DomainServiceAlias,
  DomainCalculationServiceAlias,
  ResultDomainCalculationServiceAlias,
  DomainValidationServiceAlias,
  DomainFactoryServiceAlias
} from './Service';
import { Result } from './Result';

describe('Service', () => {
  describe('DomainService interface', () => {
    it('should have optional serviceName property', () => {
      const service: DomainService = {
        serviceName: 'TestService'
      };

      expect(service.serviceName).toBe('TestService');
    });

    it('should work without serviceName', () => {
      const service: DomainService = {};

      expect(service.serviceName).toBeUndefined();
    });

    it('should support different service implementations', () => {
      const service1: DomainService = { serviceName: 'Service1' };
      const service2: DomainService = { serviceName: 'Service2' };
      const service3: DomainService = {};

      expect(service1.serviceName).toBe('Service1');
      expect(service2.serviceName).toBe('Service2');
      expect(service3.serviceName).toBeUndefined();
    });
  });

  describe('DomainCalculationService interface', () => {
    it('should have calculate method', () => {
      const service: DomainCalculationService<number, number> = {
        calculate: (input: number) => input * 2
      };

      expect(service.calculate(5)).toBe(10);
    });

    it('should support different input and output types', () => {
      const stringService: DomainCalculationService<string, string> = {
        calculate: (input: string) => input.toUpperCase()
      };

      const objectService: DomainCalculationService<{ x: number; y: number }, number> = {
        calculate: (input) => input.x + input.y
      };

      expect(stringService.calculate('hello')).toBe('HELLO');
      expect(objectService.calculate({ x: 3, y: 4 })).toBe(7);
    });

    it('should support complex calculations', () => {
      interface CalculationInput {
        values: number[];
        operation: 'sum' | 'average' | 'max';
      }

      const calculator: DomainCalculationService<CalculationInput, number> = {
        calculate: (input) => {
          switch (input.operation) {
            case 'sum':
              return input.values.reduce((a, b) => a + b, 0);
            case 'average':
              return input.values.reduce((a, b) => a + b, 0) / input.values.length;
            case 'max':
              return Math.max(...input.values);
          }
        }
      };

      expect(calculator.calculate({ values: [1, 2, 3], operation: 'sum' })).toBe(6);
      expect(calculator.calculate({ values: [1, 2, 3], operation: 'average' })).toBe(2);
      expect(calculator.calculate({ values: [1, 2, 3], operation: 'max' })).toBe(3);
    });
  });

  describe('ResultDomainCalculationService interface', () => {
    it('should have calculate method returning Result', () => {
      const service: ResultDomainCalculationService<number, number, string> = {
        calculate: (input: number) => {
          if (input < 0) {
            return Result.err('Input must be non-negative');
          }
          return Result.ok(input * 2);
        }
      };

      const successResult = service.calculate(5);
      expect(successResult.isOk()).toBe(true);
      expect(successResult.unwrap()).toBe(10);

      const errorResult = service.calculate(-1);
      expect(errorResult.isErr()).toBe(true);
      expect(errorResult.unwrapErr()).toBe('Input must be non-negative');
    });

    it('should support validation logic', () => {
      interface ValidationResult {
        isValid: boolean;
        errors: string[];
      }

      const validator: ResultDomainCalculationService<string, ValidationResult, string> = {
        calculate: (input: string) => {
          const errors: string[] = [];

          if (input.length < 3) {
            errors.push('Must be at least 3 characters');
          }

          if (!input.match(/^[a-zA-Z]+$/)) {
            errors.push('Must contain only letters');
          }

          if (errors.length > 0) {
            return Result.err(errors.join(', '));
          }

          return Result.ok({ isValid: true, errors: [] });
        }
      };

      const validResult = validator.calculate('Hello');
      expect(validResult.isOk()).toBe(true);
      expect(validResult.unwrap()).toEqual({ isValid: true, errors: [] });

      const invalidResult = validator.calculate('ab');
      expect(invalidResult.isErr()).toBe(true);
      expect(invalidResult.unwrapErr()).toBe('Must be at least 3 characters');
    });

    it('should support complex business rules', () => {
      interface DiscountInput {
        basePrice: number;
        customerType: 'regular' | 'premium' | 'vip';
        hasCoupon: boolean;
      }

      const discountCalculator: ResultDomainCalculationService<DiscountInput, number, string> = {
        calculate: (input) => {
          let discount = 0;

          // Customer type discount
          switch (input.customerType) {
            case 'premium':
              discount += 0.1;
              break;
            case 'vip':
              discount += 0.2;
              break;
          }

          // Coupon discount
          if (input.hasCoupon) {
            discount += 0.05;
          }

          // Validate price
          if (input.basePrice <= 0) {
            return Result.err('Price must be positive');
          }

          const finalPrice = input.basePrice * (1 - discount);
          return Result.ok(finalPrice);
        }
      };

      const vipWithCoupon = discountCalculator.calculate({
        basePrice: 100,
        customerType: 'vip',
        hasCoupon: true
      });

      expect(vipWithCoupon.isOk()).toBe(true);
      expect(vipWithCoupon.unwrap()).toBe(75); // 100 * (1 - 0.2 - 0.05) = 75

      const invalidPrice = discountCalculator.calculate({
        basePrice: 0,
        customerType: 'regular',
        hasCoupon: false
      });

      expect(invalidPrice.isErr()).toBe(true);
      expect(invalidPrice.unwrapErr()).toBe('Price must be positive');
    });
  });

  describe('DomainValidationService interface', () => {
    it('should have validate method returning Result', () => {
      const service: DomainValidationService<string, boolean, string> = {
        validate: (input: string) => {
          if (input.length === 0) {
            return Result.err('Input cannot be empty');
          }
          return Result.ok(true);
        }
      };

      const validResult = service.validate('test');
      expect(validResult.isOk()).toBe(true);
      expect(validResult.unwrap()).toBe(true);

      const invalidResult = service.validate('');
      expect(invalidResult.isErr()).toBe(true);
      expect(invalidResult.unwrapErr()).toBe('Input cannot be empty');
    });

    it('should support validation of complex objects', () => {
      interface UserInput {
        email: string;
        password: string;
        age: number;
      }

      const userValidator: DomainValidationService<UserInput, UserInput, string> = {
        validate: (input) => {
          const errors: string[] = [];

          if (!input.email.includes('@')) {
            errors.push('Invalid email format');
          }

          if (input.password.length < 8) {
            errors.push('Password must be at least 8 characters');
          }

          if (input.age < 18) {
            errors.push('Must be at least 18 years old');
          }

          if (errors.length > 0) {
            return Result.err(errors.join(', '));
          }

          return Result.ok(input);
        }
      };

      const validUser = userValidator.validate({
        email: 'john@example.com',
        password: 'securepassword',
        age: 25
      });

      expect(validUser.isOk()).toBe(true);
      expect(validUser.unwrap()).toEqual({
        email: 'john@example.com',
        password: 'securepassword',
        age: 25
      });

      const invalidUser = userValidator.validate({
        email: 'invalid-email',
        password: 'short',
        age: 15
      });

      expect(invalidUser.isErr()).toBe(true);
      expect(invalidUser.unwrapErr()).toContain('Invalid email format');
      expect(invalidUser.unwrapErr()).toContain('Password must be at least 8 characters');
      expect(invalidUser.unwrapErr()).toContain('Must be at least 18 years old');
    });
  });

  describe('DomainFactoryService interface', () => {
    it('should have create method', () => {
      const service: DomainFactoryService<string, { id: number; value: string }> = {
        create: (input: string) => ({
          id: input.length,
          value: input.toUpperCase()
        })
      };

      const result = service.create('test');
      expect(result).toEqual({ id: 4, value: 'TEST' });
    });

    it('should support creating complex objects', () => {
      interface CreateUserInput {
        name: string;
        email: string;
      }

      interface User {
        id: string;
        name: string;
        email: string;
        createdAt: Date;
      }

      const userFactory: DomainFactoryService<CreateUserInput, User> = {
        create: (input) => ({
          id: `user-${Date.now()}`,
          name: input.name,
          email: input.email,
          createdAt: new Date()
        })
      };

      const user = userFactory.create({
        name: 'John Doe',
        email: 'john@example.com'
      });

      expect(user.id).toMatch(/^user-\d+$/);
      expect(user.name).toBe('John Doe');
      expect(user.email).toBe('john@example.com');
      expect(user.createdAt).toBeInstanceOf(Date);
    });

    it('should support creating value objects', () => {
      interface AddressProps {
        street: string;
        city: string;
        zipCode: string;
      }

      const addressFactory: DomainFactoryService<AddressProps, AddressProps> = {
        create: (input) => ({
          street: input.street.trim(),
          city: input.city.trim(),
          zipCode: input.zipCode.trim()
        })
      };

      const address = addressFactory.create({
        street: '  123 Main St  ',
        city: '  New York  ',
        zipCode: '  10001  '
      });

      expect(address.street).toBe('123 Main St');
      expect(address.city).toBe('New York');
      expect(address.zipCode).toBe('10001');
    });
  });

  describe('ServiceAlias types', () => {
    it('should be assignable to their base interfaces', () => {
      const service1: DomainServiceAlias = { serviceName: 'Test' };
      const service2: DomainCalculationServiceAlias<number, number> = {
        calculate: (x) => x * 2
      };
      const service3: ResultDomainCalculationServiceAlias<number, number, string> = {
        calculate: (x) => Result.ok(x * 2)
      };
      const service4: DomainValidationServiceAlias<string, boolean, string> = {
        validate: (x) => Result.ok(x.length > 0)
      };
      const service5: DomainFactoryServiceAlias<string, string> = {
        create: (x) => x.toUpperCase()
      };

      expect(service1.serviceName).toBe('Test');
      expect(service2.calculate(5)).toBe(10);
      expect(service3.calculate(5).isOk()).toBe(true);
      expect(service4.validate('test').isOk()).toBe(true);
      expect(service5.create('test')).toBe('TEST');
    });
  });
});