import { describe, it, expect } from 'vitest';
import { LeagueCoverViewDataBuilder } from './LeagueCoverViewDataBuilder';
import type { MediaBinaryDTO } from '@/lib/types/generated/MediaBinaryDTO';

describe('LeagueCoverViewDataBuilder', () => {
  describe('happy paths', () => {
    it('should transform MediaBinaryDTO to LeagueCoverViewData correctly', () => {
      const buffer = new Uint8Array([0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a]);
      const mediaDto: MediaBinaryDTO = {
        buffer: buffer.buffer,
        contentType: 'image/png',
      };

      const result = LeagueCoverViewDataBuilder.build(mediaDto);

      expect(result.buffer).toBe(Buffer.from(buffer).toString('base64'));
      expect(result.contentType).toBe('image/png');
    });

    it('should handle JPEG cover images', () => {
      const buffer = new Uint8Array([0xff, 0xd8, 0xff, 0xe0]);
      const mediaDto: MediaBinaryDTO = {
        buffer: buffer.buffer,
        contentType: 'image/jpeg',
      };

      const result = LeagueCoverViewDataBuilder.build(mediaDto);

      expect(result.buffer).toBe(Buffer.from(buffer).toString('base64'));
      expect(result.contentType).toBe('image/jpeg');
    });

    it('should handle WebP cover images', () => {
      const buffer = new Uint8Array([0x52, 0x49, 0x46, 0x46]);
      const mediaDto: MediaBinaryDTO = {
        buffer: buffer.buffer,
        contentType: 'image/webp',
      };

      const result = LeagueCoverViewDataBuilder.build(mediaDto);

      expect(result.buffer).toBe(Buffer.from(buffer).toString('base64'));
      expect(result.contentType).toBe('image/webp');
    });
  });

  describe('data transformation', () => {
    it('should preserve all DTO fields in the output', () => {
      const buffer = new Uint8Array([0x89, 0x50, 0x4e, 0x47]);
      const mediaDto: MediaBinaryDTO = {
        buffer: buffer.buffer,
        contentType: 'image/png',
      };

      const result = LeagueCoverViewDataBuilder.build(mediaDto);

      expect(result.buffer).toBeDefined();
      expect(result.contentType).toBe(mediaDto.contentType);
    });

    it('should not modify the input DTO', () => {
      const buffer = new Uint8Array([0x89, 0x50, 0x4e, 0x47]);
      const mediaDto: MediaBinaryDTO = {
        buffer: buffer.buffer,
        contentType: 'image/png',
      };

      const originalDto = { ...mediaDto };
      LeagueCoverViewDataBuilder.build(mediaDto);

      expect(mediaDto).toEqual(originalDto);
    });

    it('should convert buffer to base64 string', () => {
      const buffer = new Uint8Array([0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a]);
      const mediaDto: MediaBinaryDTO = {
        buffer: buffer.buffer,
        contentType: 'image/png',
      };

      const result = LeagueCoverViewDataBuilder.build(mediaDto);

      expect(typeof result.buffer).toBe('string');
      expect(result.buffer).toBe(Buffer.from(buffer).toString('base64'));
    });
  });

  describe('edge cases', () => {
    it('should handle empty buffer', () => {
      const buffer = new Uint8Array([]);
      const mediaDto: MediaBinaryDTO = {
        buffer: buffer.buffer,
        contentType: 'image/png',
      };

      const result = LeagueCoverViewDataBuilder.build(mediaDto);

      expect(result.buffer).toBe('');
      expect(result.contentType).toBe('image/png');
    });

    it('should handle large cover images', () => {
      const buffer = new Uint8Array(2 * 1024 * 1024); // 2MB
      const mediaDto: MediaBinaryDTO = {
        buffer: buffer.buffer,
        contentType: 'image/jpeg',
      };

      const result = LeagueCoverViewDataBuilder.build(mediaDto);

      expect(result.buffer).toBe(Buffer.from(buffer).toString('base64'));
      expect(result.contentType).toBe('image/jpeg');
    });

    it('should handle buffer with all zeros', () => {
      const buffer = new Uint8Array([0x00, 0x00, 0x00, 0x00]);
      const mediaDto: MediaBinaryDTO = {
        buffer: buffer.buffer,
        contentType: 'image/png',
      };

      const result = LeagueCoverViewDataBuilder.build(mediaDto);

      expect(result.buffer).toBe(Buffer.from(buffer).toString('base64'));
      expect(result.contentType).toBe('image/png');
    });

    it('should handle buffer with all ones', () => {
      const buffer = new Uint8Array([0xff, 0xff, 0xff, 0xff]);
      const mediaDto: MediaBinaryDTO = {
        buffer: buffer.buffer,
        contentType: 'image/png',
      };

      const result = LeagueCoverViewDataBuilder.build(mediaDto);

      expect(result.buffer).toBe(Buffer.from(buffer).toString('base64'));
      expect(result.contentType).toBe('image/png');
    });
  });
});