discount/internal/utils/discount/calculate_test.go

package discount_test

import (
	"testing"

	"github.com/stretchr/testify/assert"
	"gitea.pena/PenaSide/discount/internal/core"
	"gitea.pena/PenaSide/discount/internal/models"
	"gitea.pena/PenaSide/discount/internal/utils/discount"
)

func TestCalculate(t *testing.T) {
	t.Run("Покупка продуктов в количестве не больше 1 при отсутствии скидок", func(t *testing.T) {
		assert.Equal(t, uint64(3), discount.Calculate(
			[]core.Product{
				{ID: "p1", Price: 1},
				{ID: "p2", Price: 2},
			},
			[]models.Discount{},
		))
	})

	t.Run("Сумма корзины достигла 5к", func(t *testing.T) {
		assert.Equal(t, uint64(4925), discount.Calculate(
			[]core.Product{
				{ID: "p1", Price: 2000},
				{ID: "p2", Price: 3000},
			},
			[]models.Discount{
				{
					Target: models.DiscountCalculationTarget{
						TargetScope: models.TargetSum,
						Factor:      0.985,
					},
				},
			},
		))
		assert.Equal(t, uint64(4925), discount.Calculate(
			[]core.Product{
				{ID: "p1", Price: 2000},
				{ID: "p2", Price: 3000},
			},
			[]models.Discount{
				{
					Target: models.DiscountCalculationTarget{
						Factor: 0.985,
					},
				},
			},
		))
	})

	t.Run("Наложение несколько скидок разного формата", func(t *testing.T) {
		assert.Equal(t, uint64(5025), discount.Calculate(
			[]core.Product{
				{ID: "p1", Price: 2000},
				{ID: "p2", Price: 3000},
				{ID: "p3", Price: 105},
			},
			[]models.Discount{
				{
					Target: models.DiscountCalculationTarget{
						Products: []models.ProductTarget{{ID: "p3", Factor: 0.97}},
					},
				},
				{
					Target: models.DiscountCalculationTarget{
						TargetScope: models.TargetSum,
						Factor:      0.985,
					},
				},
			},
		))
	})

	t.Run("Наложение несколько скидок разного формата с несколькими таргетами", func(t *testing.T) {
		assert.Equal(t, uint64(5223), discount.Calculate(
			[]core.Product{
				{ID: "p1", Price: 2000},
				{ID: "p2", Price: 3000},
				{ID: "p3", Price: 105},
				{ID: "p4", Price: 210},
			},
			[]models.Discount{
				{
					Target: models.DiscountCalculationTarget{
						Products: []models.ProductTarget{
							{ID: "p3", Factor: 0.97},
							{ID: "p4", Factor: 0.96},
						},
					},
				},
				{
					Target: models.DiscountCalculationTarget{
						TargetScope: models.TargetSum,
						Factor:      0.985,
					},
				},
			},
		))
	})

	t.Run("Наложение несколько скидок с наличием скидки на лояльность", func(t *testing.T) {
		assert.Equal(t, uint64(5171), discount.Calculate(
			[]core.Product{
				{ID: "p1", Price: 2000},
				{ID: "p2", Price: 3000},
				{ID: "p3", Price: 105},
				{ID: "p4", Price: 210},
			},
			[]models.Discount{
				{
					Target: models.DiscountCalculationTarget{
						Products: []models.ProductTarget{
							{ID: "p3", Factor: 0.97},
							{ID: "p4", Factor: 0.96},
						},
					},
				},
				{
					Target: models.DiscountCalculationTarget{
						TargetScope: models.TargetSum,
						Factor:      0.985,
					},
				},
				{
					Target: models.DiscountCalculationTarget{
						TargetScope: models.TargetSum,
						Factor:      0.99,
					},
				},
			},
		), 0.001)
	})

	t.Run("Наложение несколько скидок на привелегии", func(t *testing.T) {
		assert.Equal(t, uint64(422), discount.Calculate(
			[]core.Product{
				{ID: "p5", Price: 30},
				{ID: "p6", Price: 70},
				{ID: "p7", Price: 400},
			},
			[]models.Discount{
				{
					Target: models.DiscountCalculationTarget{
						Products: []models.ProductTarget{
							{ID: "p5", Factor: 0.97},
							{ID: "p6", Factor: 0.935},
						},
					},
				},
				{
					Target: models.DiscountCalculationTarget{
						Products: []models.ProductTarget{
							{ID: "p7", Factor: 0.83},
						},
					},
				},
				{
					Target: models.DiscountCalculationTarget{
						TargetScope: models.TargetSum,
						Factor:      0.99,
					},
				},
			},
		))
	})

	t.Run("Наложение несколько скидок на привелегии без лояльности", func(t *testing.T) {
		assert.Equal(t, uint64(426), discount.Calculate(
			[]core.Product{
				{ID: "p5", Price: 30},
				{ID: "p6", Price: 70},
				{ID: "p7", Price: 400},
			},
			[]models.Discount{
				{
					Target: models.DiscountCalculationTarget{
						Products: []models.ProductTarget{
							{ID: "p5", Factor: 0.97},
							{ID: "p6", Factor: 0.935},
							{ID: "p7", Factor: 0.83},
						},
					},
				},
			},
		))
	})

	t.Run("Вычисление скидки за привелегии и сервис", func(t *testing.T) {
		assert.Equal(t, uint64(743), discount.Calculate(
			[]core.Product{
				{ID: "p5", Price: 30, Group: "dwarfener"},
				{ID: "p6", Price: 70, Group: "dwarfener"},
				{ID: "p7", Price: 800, Group: "dwarfener"},
			},
			[]models.Discount{
				{
					Target: models.DiscountCalculationTarget{
						Products: []models.ProductTarget{
							{ID: "p5", Factor: 0.97},
							{ID: "p6", Factor: 0.935},
							{ID: "p7", Factor: 0.83},
						},
					},
				},
				{
					Target: models.DiscountCalculationTarget{
						Factor: 0.99,
					},
				},
				{
					Target: models.DiscountCalculationTarget{
						TargetScope: models.TargetGroup,
						TargetGroup: "dwarfener",
						Factor:      0.99,
					},
				},
			},
		))
	})

	t.Run("Наложение скидок на несколько сервисов", func(t *testing.T) {
		assert.Equal(t, uint64(2398), discount.Calculate(
			[]core.Product{
				{ID: "p1", Price: 1500, Group: "templategen"},
				{ID: "p2", Price: 300, Group: "templategen"},
				{ID: "p5", Price: 30, Group: "dwarfener"},
				{ID: "p6", Price: 70, Group: "dwarfener"},
				{ID: "p7", Price: 800, Group: "dwarfener"},
			},
			[]models.Discount{
				{
					Target: models.DiscountCalculationTarget{
						Products: []models.ProductTarget{
							{ID: "p1", Factor: 0.93},
							{ID: "p2", Factor: 0.945},
							{ID: "p5", Factor: 0.97},
							{ID: "p6", Factor: 0.935},
							{ID: "p7", Factor: 0.83},
						},
					},
				},
				{
					Target: models.DiscountCalculationTarget{
						Factor: 0.99,
					},
				},
				{
					Target: models.DiscountCalculationTarget{
						TargetScope: models.TargetGroup,
						TargetGroup: "templategen",
						Factor:      0.996,
					},
				},
				{
					Target: models.DiscountCalculationTarget{
						TargetScope: models.TargetGroup,
						TargetGroup: "dwarfener",
						Factor:      0.99,
					},
				},
			},
		))
	})

	t.Run("Наложение скидок с промокодом", func(t *testing.T) {
		assert.Equal(t, uint64(2368), discount.Calculate(
			[]core.Product{
				{ID: "p1", Price: 1500, Group: "templategen"},
				{ID: "p2", Price: 300, Group: "templategen"},
				{ID: "p5", Price: 30, Group: "dwarfener"},
				{ID: "p6", Price: 70, Group: "dwarfener"},
				{ID: "p7", Price: 800, Group: "dwarfener"},
			},
			[]models.Discount{
				{
					Target: models.DiscountCalculationTarget{
						Products: []models.ProductTarget{
							{ID: "p1", Factor: 0.93},
							{ID: "p2", Factor: 0.945},
							{ID: "p5", Factor: 0.97},
							{ID: "p6", Factor: 0.97},
							{ID: "p7", Factor: 0.83},
						},
					},
				},
				{
					Layer: 2,
					Target: models.DiscountCalculationTarget{
						Products: []models.ProductTarget{
							{ID: "p6", Factor: 0.5, Overhelm: true},
						},
					},
				},
				{
					Target: models.DiscountCalculationTarget{
						Factor: 0.94,
					},
				},
				{
					ID:    "2",
					Layer: 2,
					Target: models.DiscountCalculationTarget{
						Factor:   0.99,
						Overhelm: true,
					},
				},
				{
					Target: models.DiscountCalculationTarget{
						TargetScope: models.TargetGroup,
						TargetGroup: "templategen",
						Factor:      0.996,
					},
				},
				{
					Target: models.DiscountCalculationTarget{
						TargetScope: models.TargetGroup,
						TargetGroup: "dwarfener",
						Factor:      0.99,
					},
				},
			},
		))
	})

	t.Run("Наложение скидок по типу пользователя", func(t *testing.T) {
		assert.Equal(t, uint64(540), discount.Calculate(
			[]core.Product{
				{ID: "p1", Price: 1500, Group: "templategen"},
				{ID: "p2", Price: 300, Group: "templategen"},
				{ID: "p5", Price: 30, Group: "dwarfener"},
				{ID: "p6", Price: 70, Group: "dwarfener"},
				{ID: "p7", Price: 800, Group: "dwarfener"},
			},
			[]models.Discount{
				{
					Target: models.DiscountCalculationTarget{
						TargetScope: models.TargetSum,
						Factor:      0.2,
					},
				},
			},
		))
	})
}