import { beforeEach, describe, expect, it, vi } from 'vitest'
import { useOperationLog } from '@/composables/useOperationLog'

describe('useOperationLog', () => {
  let opLog: ReturnType<typeof useOperationLog>

  beforeEach(() => {
    opLog = useOperationLog()
    opLog.clear()
    opLog.filterType.value = ''
    opLog.searchText.value = ''
  })

  // ──── log() ────

  describe('log() 添加日志条目', () => {
    it('应添加一条日志到 entries 列表头部', () => {
      opLog.log('创建', '图层A', '新建矩形图层')

      expect(opLog.entries.value).toHaveLength(1)
      expect(opLog.entries.value[0]).toMatchObject({
        action: '创建',
        target: '图层A',
        detail: '新建矩形图层',
      })
      expect(opLog.entries.value[0].id).toBeTruthy()
      expect(opLog.entries.value[0].timestamp).toBeTruthy()
    })

    it('新日志应排在列表最前面（降序）', () => {
      opLog.log('创建', '图层A', '第一条')
      opLog.log('删除', '图层B', '第二条')

      expect(opLog.entries.value[0].action).toBe('删除')
      expect(opLog.entries.value[1].action).toBe('创建')
    })

    it('每条日志应有唯一 id', () => {
      opLog.log('创建', '图层A', '详情A')
      opLog.log('创建', '图层B', '详情B')

      const ids = opLog.entries.value.map(e => e.id)
      expect(new Set(ids).size).toBe(2)
    })

    it('超过 500 条时应截断旧日志', () => {
      for (let i = 0; i < 510; i++) {
        opLog.log('操作', `目标${i}`, `详情${i}`)
      }

      expect(opLog.entries.value).toHaveLength(500)
      // 最新的应该在最前面
      expect(opLog.entries.value[0].detail).toBe('详情509')
    })
  })

  // ──── clear() ────

  describe('clear() 清空日志', () => {
    it('应清空所有条目', () => {
      opLog.log('创建', '图层', '详情')
      opLog.log('删除', '图层', '详情')
      expect(opLog.entries.value.length).toBeGreaterThan(0)

      opLog.clear()

      expect(opLog.entries.value).toHaveLength(0)
    })

    it('清空后 filteredEntries 也应为空', () => {
      opLog.log('创建', '图层', '详情')
      opLog.clear()

      expect(opLog.filteredEntries.value).toHaveLength(0)
    })
  })

  // ──── filteredEntries ────

  describe('filteredEntries 过滤逻辑', () => {
    beforeEach(() => {
      opLog.log('创建', '图层A', '新建矩形')
      opLog.log('删除', '图层B', '删除圆形')
      opLog.log('修改', '图层C', '修改颜色属性')
      opLog.log('创建', '图层D', '新建文本')
    })

    it('无过滤条件时应返回全部条目', () => {
      expect(opLog.filteredEntries.value).toHaveLength(4)
    })

    it('按 filterType 过滤 action', () => {
      opLog.filterType.value = '创建'

      expect(opLog.filteredEntries.value).toHaveLength(2)
      expect(opLog.filteredEntries.value.every(e => e.action === '创建')).toBe(true)
    })

    it('按 searchText 模糊搜索 detail', () => {
      opLog.searchText.value = '矩形'

      expect(opLog.filteredEntries.value).toHaveLength(1)
      expect(opLog.filteredEntries.value[0].detail).toBe('新建矩形')
    })

    it('按 searchText 模糊搜索 target', () => {
      opLog.searchText.value = '图层B'

      expect(opLog.filteredEntries.value).toHaveLength(1)
      expect(opLog.filteredEntries.value[0].target).toBe('图层B')
    })

    it('searchText 不区分大小写', () => {
      opLog.log('创建', 'LayerX', 'New Rectangle')
      opLog.searchText.value = 'rectangle'

      expect(opLog.filteredEntries.value).toHaveLength(1)
      expect(opLog.filteredEntries.value[0].detail).toBe('New Rectangle')
    })

    it('同时使用 filterType 和 searchText', () => {
      opLog.filterType.value = '创建'
      opLog.searchText.value = '文本'

      expect(opLog.filteredEntries.value).toHaveLength(1)
      expect(opLog.filteredEntries.value[0].target).toBe('图层D')
    })

    it('过滤条件无匹配时返回空数组', () => {
      opLog.filterType.value = '不存在的操作'

      expect(opLog.filteredEntries.value).toHaveLength(0)
    })
  })

  // ──── exportJSON() ────

  describe('exportJSON() 导出日志', () => {
    it('应创建下载链接并触发点击', () => {
      opLog.log('创建', '图层', '详情')

      const mockClick = vi.fn()
      const mockAppendChild = vi.spyOn(document.body, 'appendChild').mockImplementation(node => node)
      const mockRemoveChild = vi.spyOn(document.body, 'removeChild').mockImplementation(node => node)
      const mockCreateElement = vi.spyOn(document, 'createElement').mockReturnValue({
        get href() { return '' },
        set href(_: string) {},
        get download() { return '' },
        set download(_: string) {},
        click: mockClick,
      } as unknown as HTMLAnchorElement)
      const mockRevokeObjectURL = vi.spyOn(URL, 'revokeObjectURL').mockImplementation(() => {})
      const mockCreateObjectURL = vi.spyOn(URL, 'createObjectURL').mockReturnValue('blob:test')

      opLog.exportJSON()

      expect(mockCreateObjectURL).toHaveBeenCalled()
      expect(mockClick).toHaveBeenCalled()
      expect(mockRevokeObjectURL).toHaveBeenCalledWith('blob:test')

      mockAppendChild.mockRestore()
      mockRemoveChild.mockRestore()
      mockCreateElement.mockRestore()
      mockRevokeObjectURL.mockRestore()
      mockCreateObjectURL.mockRestore()
    })
  })

  // ──── 单例共享 ────

  describe('单例模式', () => {
    it('多次调用 useOperationLog() 应共享同一份状态', () => {
      const log1 = useOperationLog()
      const log2 = useOperationLog()

      log1.log('测试', '目标', '详情')

      expect(log2.entries.value).toHaveLength(log1.entries.value.length)
      expect(log2.entries.value[0].id).toBe(log1.entries.value[0].id)
    })
  })
})