const { Cart } = require('./solution');

describe('Cart', () => {
  test('empty cart totals', () => {
    const c = new Cart();
    expect(c.subtotal()).toBe(0);
    expect(c.discount()).toBe(0);
    expect(c.shipping()).toBe(0);
    expect(c.total()).toBe(0);
  });
  test('add merges quantities and is chainable', () => {
    const c = new Cart().add('a', 'Kalem', 1000).add('a', 'Kalem', 1000, 2);
    expect(c.items.get('a').qty).toBe(3);
    expect(c.subtotal()).toBe(3000);
  });
  test.each([[-1, 1], [1.5, 1], ['10', 1]])('rejects bad price %p', (p, q) => {
    expect(() => new Cart().add('x', 'X', p, q)).toThrow(TypeError);
  });
  test.each([0, 1.5])('rejects bad qty %p', (q) => {
    expect(() => new Cart().add('x', 'X', 100, q)).toThrow(RangeError);
  });
  test('remove partially, fully and unknown', () => {
    const c = new Cart().add('a', 'A', 100, 3);
    expect(c.remove('a', 1)).toBe(true);
    expect(c.items.get('a').qty).toBe(2);
    expect(c.remove('a')).toBe(true);
    expect(c.items.size).toBe(0);
    expect(c.remove('zz')).toBe(false);
  });
  test('percent coupon is case-insensitive and rounds', () => {
    const c = new Cart().add('a', 'A', 1005);
    c.applyCoupon('yuzde10');
    expect(c.discount()).toBe(101);
  });
  test('fixed coupon is capped at subtotal', () => {
    const c = new Cart().add('a', 'A', 3000);
    c.applyCoupon('INDIRIM50');
    expect(c.discount()).toBe(3000);
    expect(c.total()).toBe(2999);
  });
  test('invalid coupon throws', () => {
    expect(() => new Cart().applyCoupon('YOK')).toThrow('Geçersiz kupon');
  });
  test('free shipping threshold uses discounted amount', () => {
    const c = new Cart().add('a', 'A', 50000);
    expect(c.shipping()).toBe(0);
    c.applyCoupon('YUZDE10');
    expect(c.shipping()).toBe(2999);
    expect(c.total()).toBe(50000 - 5000 + 2999);
  });
  test('below threshold pays shipping', () => {
    expect(new Cart().add('a', 'A', 49999).shipping()).toBe(2999);
  });
});