package model

import (
	"testing"
	"time"
)

func TestConsumableLowStockAlert(t *testing.T) {
	c := Consumable{Quantity: 5, MinQuantity: 10}
	if !c.LowStockAlert() {
		t.Error("库存低于安全阈值应预警")
	}
	c2 := Consumable{Quantity: 10, MinQuantity: 10}
	if c2.LowStockAlert() {
		t.Error("库存等于安全阈值不应预警")
	}
}

func TestConsumableExpiringAlert(t *testing.T) {
	soon := time.Now().Add(10 * 24 * time.Hour)
	if !(Consumable{ExpiryDate: &soon}).ExpiringAlert(30) {
		t.Error("30 天内到期应预警")
	}
	past := time.Now().Add(-24 * time.Hour)
	if !(Consumable{ExpiryDate: &past}).ExpiringAlert(30) {
		t.Error("已过期应预警")
	}
	far := time.Now().Add(60 * 24 * time.Hour)
	if (Consumable{ExpiryDate: &far}).ExpiringAlert(30) {
		t.Error("60 天后到期不应预警（30 天窗口）")
	}
	if (Consumable{}).ExpiringAlert(30) {
		t.Error("无效期不应预警")
	}
}

func TestPurchaseSuggestion(t *testing.T) {
	if s := (Consumable{Quantity: 3, MinQuantity: 10}).PurchaseSuggestion(); s != 7 {
		t.Errorf("建议采购量 = %v, want 7", s)
	}
	if s := (Consumable{Quantity: 10, MinQuantity: 10}).PurchaseSuggestion(); s != 0 {
		t.Errorf("不缺货建议采购量 = %v, want 0", s)
	}
}