import { describe, it, expect, vi, beforeEach } from 'vitest'
import { computed, ref } from 'vue'

vi.mock('@/api/login', () => ({
  login: vi.fn(),
  logout: vi.fn().mockResolvedValue({ code: 200 }),
}))

vi.mock('element-plus', () => ({
  ElMessage: {
    success: vi.fn(),
    error: vi.fn(),
    warning: vi.fn(),
    info: vi.fn(),
  },
}))

import { logout } from '@/api/login'
import { ElMessage } from 'element-plus'

describe('MyHead.vue logic', () => {
  beforeEach(() => {
    vi.clearAllMocks()
    localStorage.clear()
  })

  describe('route-based computed properties', () => {
    it('isLoginRoute is true when path is /login', () => {
      const routePath = ref('/login')
      const isLoginRoute = computed(() => routePath.value === '/login')
      expect(isLoginRoute.value).toBe(true)
    })

    it('isLoginRoute is false for other paths', () => {
      const routePath = ref('/welcome')
      const isLoginRoute = computed(() => routePath.value === '/login')
      expect(isLoginRoute.value).toBe(false)
    })

    it('showBackButton is true for non-login, non-welcome routes', () => {
      const routePath = ref('/study')
      const showBackButton = computed(() => routePath.value !== '/login' && routePath.value !== '/welcome')
      expect(showBackButton.value).toBe(true)
    })

    it('showBackButton is false on welcome route', () => {
      const routePath = ref('/welcome')
      const showBackButton = computed(() => routePath.value !== '/login' && routePath.value !== '/welcome')
      expect(showBackButton.value).toBe(false)
    })

    it('showBackButton is false on login route', () => {
      const routePath = ref('/login')
      const showBackButton = computed(() => routePath.value !== '/login' && routePath.value !== '/welcome')
      expect(showBackButton.value).toBe(false)
    })

    it('pageTitle is derived from route meta', () => {
      const meta = { title: '学习任务' }
      const pageTitle = computed(() => meta?.title as string | undefined)
      expect(pageTitle.value).toBe('学习任务')
    })

    it('pageTitle is undefined when no meta title', () => {
      const meta = {}
      const pageTitle = computed(() => meta?.title as string | undefined)
      expect(pageTitle.value).toBeUndefined()
    })
  })

  describe('handleLogout logic', () => {
    it('clears login state and navigates to login', async () => {
      localStorage.setItem('isLoggedIn', 'true')

      // Simulate handleLogout
      try {
        await logout()
      } catch {
        // Backend failure shouldn't block logout
      } finally {
        localStorage.removeItem('isLoggedIn')
        ElMessage.success('已退出登录')
      }

      expect(localStorage.getItem('isLoggedIn')).toBeNull()
      expect(ElMessage.success).toHaveBeenCalledWith('已退出登录')
    })

    it('clears login state even when API call fails', async () => {
      vi.mocked(logout).mockRejectedValue(new Error('Network error'))
      localStorage.setItem('isLoggedIn', 'true')

      try {
        await logout()
      } catch {
        // Expected
      } finally {
        localStorage.removeItem('isLoggedIn')
        ElMessage.success('已退出登录')
      }

      expect(localStorage.getItem('isLoggedIn')).toBeNull()
      expect(ElMessage.success).toHaveBeenCalledWith('已退出登录')
    })
  })
})