import { TypeInferrer } from '../src/type-inferrer.js';
import { DeclarationGenerator } from '../src/declaration-generator.js';

describe('Union Type Detection', () => {
  describe('TypeInferrer union detection', () => {
    it('should detect union types when field has different types across samples', () => {
      const inferrer = new TypeInferrer({ rootName: 'Test' });
      const result = inferrer.inferFromMultiple([
        { value: 1 },
        { value: 'two' },
      ]);
      expect(result.types.length).toBeGreaterThan(0);
    });

    it('should detect union with null type', () => {
      const inferrer = new TypeInferrer({ rootName: 'Test' });
      const result = inferrer.inferFromMultiple([
        { value: 'string' },
        { value: null },
      ]);
      expect(result.types.length).toBeGreaterThan(0);
    });

    it('should handle multiple union members', () => {
      const inferrer = new TypeInferrer({ rootName: 'Test' });
      const result = inferrer.inferFromMultiple([
        { id: 1 },
        { id: 'abc' },
        { id: true },
      ]);
      expect(result.types.length).toBeGreaterThan(0);
    });

    it('should not create union for single type', () => {
      const inferrer = new TypeInferrer({ rootName: 'Test' });
      const result = inferrer.inferFromMultiple([
        { value: 1 },
        { value: 2 },
        { value: 3 },
      ]);
      expect(result.types.length).toBeGreaterThan(0);
    });

    it('should detect union in nested objects', () => {
      const inferrer = new TypeInferrer({ rootName: 'Test' });
      const result = inferrer.inferFromMultiple([
        { nested: { id: 1 } },
        { nested: { id: 'str' } },
      ]);
      expect(result.types.length).toBeGreaterThan(0);
    });

    it('should detect union in arrays', () => {
      const inferrer = new TypeInferrer({ rootName: 'Test' });
      const result = inferrer.inferFromMultiple([
        { items: [1, 2] },
        { items: ['a', 'b'] },
      ]);
      expect(result.types.length).toBeGreaterThan(0);
    });
  });

  describe('Integration: infer and generate', () => {
    it('should generate valid union type declarations', () => {
      const inferrer = new TypeInferrer({ rootName: 'Response' });
      const result = inferrer.inferFromMultiple([
        { id: 1, type: 'user' },
        { id: '2', type: 'admin' },
      ]);

      const generator = new DeclarationGenerator();
      const declaration = generator.generate(result.types);

      expect(declaration).toContain('export interface Response');
      expect(declaration).toContain('id');
      expect(declaration).toContain('type');
    });
  });
});