backend/tests/mandi.test.js

/**
 * Mandi Prices Routes Tests
 */
describe('Mandi Prices', () => {
  it('should generate price data for commodity', () => {
    const basePrice = 2200; // wheat
    const days = 30;
    const prices = Array.from({ length: days }, () => {
      const variation = (Math.random() - 0.5) * basePrice * 0.08;
      return Math.round(basePrice + variation);
    });

    expect(prices).toHaveLength(30);
    prices.forEach(p => {
      expect(p).toBeGreaterThan(0);
    });
  });

  it('should calculate statistics correctly', () => {
    const prices = [2200, 2300, 2100, 2250, 2180];
    const avg = Math.round(prices.reduce((a, b) => a + b, 0) / prices.length);
    const min = Math.min(...prices);
    const max = Math.max(...prices);
    const trend = prices[prices.length - 1] > prices[0] ? 'rising' : 'falling';

    expect(avg).toBe(2206);
    expect(min).toBe(2100);
    expect(max).toBe(2300);
    expect(trend).toBe('falling');
  });

  it('should have valid commodity list', () => {
    const commodities = ['wheat', 'rice', 'groundnut', 'soybean', 'mustard', 'cotton'];
    expect(commodities.length).toBeGreaterThan(5);
    commodities.forEach(c => {
      expect(typeof c).toBe('string');
      expect(c.length).toBeGreaterThan(0);
    });
  });

  it('should limit days to max 90', () => {
    const days = Math.min(parseInt('100'), 90);
    expect(days).toBe(90);
  });
});