/**
 * 物品系统单元测试
 * 测试纯函数，不依赖框架
 */

describe('物品系统 - 纯函数测试', () => {
  describe('getQualityLevel - 品质等级计算', () => {
    const QUALITY_LEVELS = {
      1: { level: 1, name: '垃圾', color: '#9e9e9e', range: [0, 49], multiplier: 0.5 },
      2: { level: 2, name: '普通', color: '#ffffff', range: [50, 99], multiplier: 1.0 },
      3: { level: 3, name: '优秀', color: '#1eff00', range: [100, 129], multiplier: 1.3 },
      4: { level: 4, name: '稀有', color: '#0070dd', range: [130, 159], multiplier: 1.6 },
      5: { level: 5, name: '史诗', color: '#a335ee', range: [160, 199], multiplier: 2.0 },
      6: { level: 6, name: '传说', color: '#ff8000', range: [200, 250], multiplier: 2.5 }
    }

    const getQualityLevel = (quality) => {
      const clampedQuality = Math.max(0, Math.min(250, quality))

      for (const [level, data] of Object.entries(QUALITY_LEVELS)) {
        if (clampedQuality >= data.range[0] && clampedQuality <= data.range[1]) {
          return {
            level: parseInt(level),
            ...data
          }
        }
      }

      return QUALITY_LEVELS[1]
    }

    test('应该正确识别垃圾品质', () => {
      const level = getQualityLevel(0)
      expect(level.level).toBe(1)
      expect(level.name).toBe('垃圾')
      expect(level.multiplier).toBe(0.5)
    })

    test('应该正确识别普通品质', () => {
      const level = getQualityLevel(75)
      expect(level.level).toBe(2)
      expect(level.name).toBe('普通')
      expect(level.multiplier).toBe(1.0)
    })

    test('应该正确识别优秀品质', () => {
      const level = getQualityLevel(115)
      expect(level.level).toBe(3)
      expect(level.name).toBe('优秀')
      expect(level.multiplier).toBe(1.3)
    })

    test('应该正确识别稀有品质', () => {
      const level = getQualityLevel(145)
      expect(level.level).toBe(4)
      expect(level.name).toBe('稀有')
      expect(level.multiplier).toBe(1.6)
    })

    test('应该正确识别史诗品质', () => {
      const level = getQualityLevel(180)
      expect(level.level).toBe(5)
      expect(level.name).toBe('史诗')
      expect(level.multiplier).toBe(2.0)
    })

    test('应该正确识别传说品质', () => {
      const level = getQualityLevel(220)
      expect(level.level).toBe(6)
      expect(level.name).toBe('传说')
      expect(level.multiplier).toBe(2.5)
    })

    test('品质边界值测试', () => {
      expect(getQualityLevel(49).level).toBe(1)   // 垃圾上限
      expect(getQualityLevel(50).level).toBe(2)   // 普通下限
      expect(getQualityLevel(99).level).toBe(2)   // 普通上限
      expect(getQualityLevel(100).level).toBe(3)  // 优秀下限
      expect(getQualityLevel(250).level).toBe(6)  // 传说上限
    })

    test('超出范围应该被限制', () => {
      expect(getQualityLevel(-10).level).toBe(1)  // 负数
      expect(getQualityLevel(300).level).toBe(6)  // 超过250
    })
  })

  describe('calculateItemStats - 物品属性计算', () => {
    test('应该正确计算武器伤害', () => {
      const baseDamage = 10
      const quality = 100
      const qualityMultiplier = 1.3
      const qualityRatio = quality / 100

      const finalDamage = Math.floor(baseDamage * qualityRatio * qualityMultiplier)

      expect(finalDamage).toBe(13)  // 10 * 1.0 * 1.3 = 13
    })

    test('应该正确计算防御力', () => {
      const baseDefense = 20
      const quality = 150
      const qualityMultiplier = 1.6
      const qualityRatio = quality / 100

      const finalDefense = Math.floor(baseDefense * qualityRatio * qualityMultiplier)

      expect(finalDefense).toBe(48)  // 20 * 1.5 * 1.6 = 48
    })

    test('应该正确计算物品价值', () => {
      const baseValue = 100
      const quality = 120
      const qualityMultiplier = 1.3
      const qualityRatio = quality / 100

      const finalValue = Math.floor(baseValue * qualityRatio * qualityMultiplier)

      expect(finalValue).toBe(156)  // 100 * 1.2 * 1.3 = 156
    })

    test('品质为0时应该有最小值', () => {
      const baseDamage = 10
      const quality = 0
      const qualityMultiplier = 0.5
      const qualityRatio = quality / 100

      const finalDamage = Math.floor(baseDamage * qualityRatio * qualityMultiplier)

      expect(finalDamage).toBe(0)  // 10 * 0 * 0.5 = 0
    })
  })

  describe('generateRandomQuality - 随机品质生成', () => {
    test('基础品质范围应该是50-150', () => {
      const baseMin = 50
      const baseMax = 150

      const randomQuality = baseMin + Math.floor(Math.random() * (baseMax - baseMin + 1))

      expect(randomQuality).toBeGreaterThanOrEqual(50)
      expect(randomQuality).toBeLessThanOrEqual(150)
    })

    test('运气应该增加品质', () => {
      const baseQuality = 100
      const luck = 20
      const luckBonus = luck * 0.5

      const finalQuality = baseQuality + luckBonus

      expect(finalQuality).toBe(110)  // 100 + 20 * 0.5 = 110
    })

    test('品质应该被限制在0-250之间', () => {
      const clamp = (value) => Math.min(250, Math.max(0, value))

      expect(clamp(-10)).toBe(0)
      expect(clamp(0)).toBe(0)
      expect(clamp(250)).toBe(250)
      expect(clamp(300)).toBe(250)
    })

    test('传说品质应该非常稀有', () => {
      // 传说品质概率 < 0.02
      const legendaryChance = 0.01 + 50 / 10000

      expect(legendaryChance).toBeLessThan(0.02)
    })

    test('史诗品质应该稀有', () => {
      // 史诗品质概率 < 0.08
      const epicChance = 0.05 + 50 / 2000

      expect(epicChance).toBeLessThan(0.08)
    })
  })

  describe('calculateSellPrice - 出售价格计算', () => {
    test('应该正确计算基础出售价格', () => {
      const baseValue = 100
      const sellRate = 0.5  // 50%

      const sellPrice = Math.floor(baseValue * sellRate)

      expect(sellPrice).toBe(50)
    })

    test('品质应该影响出售价格', () => {
      const baseValue = 100
      const quality = 120
      const qualityMultiplier = 1.3
      const sellRate = 0.5

      const sellPrice = Math.floor(baseValue * (quality / 100) * qualityMultiplier * sellRate)

      expect(sellPrice).toBe(78)  // 100 * 1.2 * 1.3 * 0.5 = 78
    })

    test('市场倍率应该影响价格', () => {
      const baseValue = 100
      const quality = 100
      const qualityMultiplier = 1.0
      const marketRate = 1.5  // 市场繁荣

      const sellPrice = Math.floor(baseValue * 1.0 * qualityMultiplier * 0.5 * marketRate)

      expect(sellPrice).toBe(75)  // 100 * 1.0 * 1.0 * 0.5 * 1.5 = 75
    })
  })

  describe('calculateBuyPrice - 购买价格计算', () => {
    test('应该正确计算基础购买价格', () => {
      const baseValue = 100
      const buyRate = 1.5  // 150%

      const buyPrice = Math.floor(baseValue * buyRate)

      expect(buyPrice).toBe(150)
    })

    test('品质应该影响购买价格', () => {
      const baseValue = 100
      const quality = 150
      const qualityMultiplier = 1.6
      const buyRate = 1.5

      const buyPrice = Math.floor(baseValue * (quality / 100) * qualityMultiplier * buyRate)

      expect(buyPrice).toBe(360)  // 100 * 1.5 * 1.6 * 1.5 = 360
    })
  })

  describe('物品堆叠', () => {
    test('可堆叠物品应该有最大堆叠数', () => {
      const stackable = true
      const maxStack = 99

      const canAddToStack = (currentStack, amount) => {
        return currentStack + amount <= maxStack
      }

      expect(canAddToStack(50, 40)).toBe(true)
      expect(canAddToStack(50, 49)).toBe(true)
      expect(canAddToStack(50, 50)).toBe(false)
    })

    test('不可堆叠物品每次只能有一个', () => {
      const stackable = false
      const maxStack = 1

      const canAddToStack = (currentStack) => {
        return currentStack < maxStack
      }

      expect(canAddToStack(0)).toBe(true)
      expect(canAddToStack(1)).toBe(false)
    })

    test('使用堆叠物品应该减少数量', () => {
      const itemCount = 10
      const useCount = 3

      const remainingCount = itemCount - useCount

      expect(remainingCount).toBe(7)
    })

    test('堆叠为0时物品应该被移除', () => {
      const itemCount = 1
      const useCount = 1

      const shouldRemove = itemCount - useCount <= 0

      expect(shouldRemove).toBe(true)
    })
  })

  describe('装备物品', () => {
    test('武器应该装备到武器槽', () => {
      const itemType = 'weapon'
      const equipment = {
        weapon: null,
        armor: null
      }

      const canEquip = (slot) => {
        return equipment[slot] === null
      }

      expect(canEquip('weapon')).toBe(true)
      expect(canEquip('armor')).toBe(true)
    })

    test('装备槽已占用时不能装备', () => {
      const equipment = {
        weapon: { id: 'old_sword' }
      }

      const canEquip = (slot) => {
        return equipment[slot] === null
      }

      expect(canEquip('weapon')).toBe(false)
    })

    test('双手武器应该占用两个槽位', () => {
      const item = {
        id: 'two_handed_sword',
        twoHanded: true
      }

      const slotsNeeded = item.twoHanded ? 2 : 1

      expect(slotsNeeded).toBe(2)
    })
  })

  describe('消耗品效果', () => {
    test('生命药水应该恢复生命值', () => {
      const currentHealth = 50
      const maxHealth = 100
      const healAmount = 30

      const newHealth = Math.min(maxHealth, currentHealth + healAmount)

      expect(newHealth).toBe(80)
    })

    test('生命值已满时不应该溢出', () => {
      const currentHealth = 100
      const maxHealth = 100
      const healAmount = 30

      const newHealth = Math.min(maxHealth, currentHealth + healAmount)

      expect(newHealth).toBe(100)
    })

    test('耐力药水应该恢复耐力', () => {
      const currentStamina = 20
      const maxStamina = 100
      const restoreAmount = 50

      const newStamina = Math.min(maxStamina, currentStamina + restoreAmount)

      expect(newStamina).toBe(70)
    })
  })

  describe('边界条件', () => {
    test('品质为负数时应该设为0', () => {
      const quality = -10
      const clampedQuality = Math.max(0, quality)

      expect(clampedQuality).toBe(0)
    })

    test('品质超过250时应该设为250', () => {
      const quality = 300
      const clampedQuality = Math.min(250, quality)

      expect(clampedQuality).toBe(250)
    })

    test('物品价值不能为负数', () => {
      const baseValue = -100
      const finalValue = Math.max(0, baseValue)

      expect(finalValue).toBe(0)
    })

    test('伤害不能为负数', () => {
      const baseDamage = -10
      const qualityRatio = 1.0
      const qualityMultiplier = 1.0

      const finalDamage = Math.max(0, Math.floor(baseDamage * qualityRatio * qualityMultiplier))

      expect(finalDamage).toBe(0)
    })
  })
})