import { describe, it, expect } from 'vitest';
import { HealthMetricFormatter } from './HealthMetricFormatter';

describe('HealthMetricFormatter', () => {
  describe('formatUptime', () => {
    it('should format uptime as percentage with 2 decimal places', () => {
      expect(HealthMetricFormatter.formatUptime(99.99)).toBe('99.99%');
      expect(HealthMetricFormatter.formatUptime(95.5)).toBe('95.50%');
    });

    it('should handle undefined uptime', () => {
      expect(HealthMetricFormatter.formatUptime(undefined)).toBe('N/A');
    });

    it('should handle null uptime', () => {
      expect(HealthMetricFormatter.formatUptime(null)).toBe('N/A');
    });

    it('should handle negative uptime', () => {
      expect(HealthMetricFormatter.formatUptime(-1)).toBe('N/A');
    });

    it('should handle zero uptime', () => {
      expect(HealthMetricFormatter.formatUptime(0)).toBe('0.00%');
    });
  });

  describe('formatResponseTime', () => {
    it('should format response time in milliseconds for values under 1000', () => {
      expect(HealthMetricFormatter.formatResponseTime(123)).toBe('123ms');
      expect(HealthMetricFormatter.formatResponseTime(999)).toBe('999ms');
    });

    it('should format response time in seconds for values between 1000 and 60000', () => {
      expect(HealthMetricFormatter.formatResponseTime(1000)).toBe('1.00s');
      expect(HealthMetricFormatter.formatResponseTime(12345)).toBe('12.35s');
      expect(HealthMetricFormatter.formatResponseTime(59999)).toBe('60.00s');
    });

    it('should format response time in minutes for values 60000 or above', () => {
      expect(HealthMetricFormatter.formatResponseTime(60000)).toBe('1.00m');
      expect(HealthMetricFormatter.formatResponseTime(123456)).toBe('2.06m');
    });

    it('should handle undefined response time', () => {
      expect(HealthMetricFormatter.formatResponseTime(undefined)).toBe('N/A');
    });

    it('should handle null response time', () => {
      expect(HealthMetricFormatter.formatResponseTime(null)).toBe('N/A');
    });

    it('should handle negative response time', () => {
      expect(HealthMetricFormatter.formatResponseTime(-1)).toBe('N/A');
    });

    it('should handle zero response time', () => {
      expect(HealthMetricFormatter.formatResponseTime(0)).toBe('0ms');
    });
  });

  describe('formatErrorRate', () => {
    it('should format error rate as percentage with 2 decimal places', () => {
      expect(HealthMetricFormatter.formatErrorRate(0.5)).toBe('0.50%');
      expect(HealthMetricFormatter.formatErrorRate(12.34)).toBe('12.34%');
    });

    it('should handle undefined error rate', () => {
      expect(HealthMetricFormatter.formatErrorRate(undefined)).toBe('N/A');
    });

    it('should handle null error rate', () => {
      expect(HealthMetricFormatter.formatErrorRate(null)).toBe('N/A');
    });

    it('should handle negative error rate', () => {
      expect(HealthMetricFormatter.formatErrorRate(-1)).toBe('N/A');
    });

    it('should handle zero error rate', () => {
      expect(HealthMetricFormatter.formatErrorRate(0)).toBe('0.00%');
    });
  });

  describe('formatTimestamp', () => {
    it('should format timestamp correctly', () => {
      const timestamp = '2026-01-15T14:30:45Z';
      const result = HealthMetricFormatter.formatTimestamp(timestamp);
      expect(result).toBe('Jan 15, 2026, 14:30:45');
    });

    it('should handle different timestamps', () => {
      const timestamp = '2026-12-25T09:15:30Z';
      const result = HealthMetricFormatter.formatTimestamp(timestamp);
      expect(result).toBe('Dec 25, 2026, 09:15:30');
    });
  });

  describe('formatSuccessRate', () => {
    it('should format success rate correctly', () => {
      expect(HealthMetricFormatter.formatSuccessRate(95, 5)).toBe('95.0%');
      expect(HealthMetricFormatter.formatSuccessRate(99, 1)).toBe('99.0%');
    });

    it('should handle zero total checks', () => {
      expect(HealthMetricFormatter.formatSuccessRate(0, 0)).toBe('N/A');
    });

    it('should handle only passed checks', () => {
      expect(HealthMetricFormatter.formatSuccessRate(100, 0)).toBe('100.0%');
    });

    it('should handle only failed checks', () => {
      expect(HealthMetricFormatter.formatSuccessRate(0, 100)).toBe('0.0%');
    });

    it('should handle undefined checks', () => {
      expect(HealthMetricFormatter.formatSuccessRate(undefined, undefined)).toBe('N/A');
    });

    it('should handle null checks', () => {
      expect(HealthMetricFormatter.formatSuccessRate(null, null)).toBe('N/A');
    });
  });
});