const { FONT_FAMILY, calcFontSize, estimateTextWidth } = require('../src/lib/svg-utils');

describe('svg-utils', () => {

  describe('FONT_FAMILY', () => {
    it('should be a non-empty string', () => {
      expect(typeof FONT_FAMILY).toBe('string');
      expect(FONT_FAMILY.length).toBeGreaterThan(0);
    });

    it('should contain Verdana', () => {
      expect(FONT_FAMILY).toContain('Verdana');
    });
  });

  describe('calcFontSize', () => {
    it('should return 60% of size rounded', () => {
      expect(calcFontSize(24)).toBe(14);
      expect(calcFontSize(100)).toBe(60);
      expect(calcFontSize(16)).toBe(10);
    });

    it('should round correctly', () => {
      expect(calcFontSize(25)).toBe(15);
      expect(calcFontSize(33)).toBe(20); // 33 * 0.6 = 19.8 → 20
    });
  });

  describe('estimateTextWidth', () => {
    it('should estimate width based on text length and font size', () => {
      const width = estimateTextWidth('Hello', 14);
      // formula: text.length * fontSize * 0.65 + fontSize * 0.8
      expect(width).toBe(5 * 14 * 0.65 + 14 * 0.8); // 56.7
    });

    it('should include padding for empty string', () => {
      // Even empty strings get the base padding
      expect(estimateTextWidth('', 14)).toBe(14 * 0.8); // 11.2
    });

    it('should scale with font size', () => {
      const w1 = estimateTextWidth('test', 10);
      const w2 = estimateTextWidth('test', 20);
      // w1 = 4*10*0.65 + 10*0.8 = 34
      // w2 = 4*20*0.65 + 20*0.8 = 68
      expect(w2).toBe(68);
    });
  });
});