import { describe, it, expect, vi, beforeEach } from 'vitest'
import { mount } from '@vue/test-utils'
import { createRouter, createMemoryHistory } from 'vue-router'
import { reactive, ref } from 'vue'

// Mock API
vi.mock('@/api/login', () => ({
  login: vi.fn(),
  logout: vi.fn(),
}))

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

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

function createTestRouter() {
  return createRouter({
    history: createMemoryHistory(),
    routes: [
      { path: '/login', component: { template: '<div/>' } },
      { path: '/welcome', component: { template: '<div/>' } },
    ],
  })
}

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

  describe('isNotEmpty validator', () => {
    it('calls callback with error message when value is empty', () => {
      const callback = vi.fn()
      const rule = { message: '请输入账号！' }
      // isNotEmpty logic
      const value = ''
      if (!value) {
        callback(rule.message)
      } else {
        callback()
      }
      expect(callback).toHaveBeenCalledWith('请输入账号！')
    })

    it('calls callback without error when value is present', () => {
      const callback = vi.fn()
      const rule = { message: '请输入账号！' }
      const value = 'admin'
      if (!value) {
        callback(rule.message)
      } else {
        callback()
      }
      expect(callback).toHaveBeenCalledWith()
    })
  })

  describe('submitForm logic', () => {
    it('sets localStorage and navigates on successful login', async () => {
      vi.mocked(login).mockResolvedValue({ code: 200, message: '登录成功' } as any)
      const router = createTestRouter()
      await router.push('/login')
      await router.isReady()

      // Simulate submitForm logic
      const username = 'admin'
      const password = '123456'
      const result = await login(username, password)

      if (result.code === 200) {
        localStorage.setItem('isLoggedIn', 'true')
        ElMessage.success(result.message)
        await router.push('/welcome')
      }

      expect(localStorage.getItem('isLoggedIn')).toBe('true')
      expect(ElMessage.success).toHaveBeenCalledWith('登录成功')
      expect(router.currentRoute.value.path).toBe('/welcome')
    })

    it('shows error message on failed login', async () => {
      vi.mocked(login).mockResolvedValue({ code: 401, message: '密码错误' } as any)

      const result = await login('admin', 'wrong')
      if (result.code !== 200) {
        ElMessage.error(result.message)
      }

      expect(ElMessage.error).toHaveBeenCalledWith('密码错误')
      expect(localStorage.getItem('isLoggedIn')).toBeNull()
    })

    it('does not submit when already loading', async () => {
      const loading = ref(true)
      // Simulate guard: if (!formEl || loading.value) return;
      if (loading.value) {
        // Early return - no API call
      }
      expect(login).not.toHaveBeenCalled()
    })
  })
})