import { describe, it, expect, vi, beforeEach } from 'vitest'
import { createRouter, createMemoryHistory } from 'vue-router'

// We test the guard logic by importing the router and simulating navigation
// The router in src/router/index.ts uses createWebHistory which requires DOM,
// so we'll test the guard logic by recreating the key patterns.

describe('route guards', () => {
  beforeEach(() => {
    localStorage.clear()
    vi.restoreAllMocks()
  })

  function buildRouter() {
    return createRouter({
      history: createMemoryHistory(),
      routes: [
        { path: '/login', component: { template: '<div/>' }, meta: { requiresAuth: false } },
        { path: '/welcome', component: { template: '<div/>' }, meta: { requiresAuth: true } },
        { path: '/study', component: { template: '<div/>' }, meta: { requiresAuth: true } },
        { path: '/', redirect: '/login' },
      ],
    })
  }

  it('redirects unauthenticated user from protected route to /login', async () => {
    const router = buildRouter()
    router.beforeEach((to, _from, next) => {
      const isLoggedIn = localStorage.getItem('isLoggedIn') === 'true'
      if (to.meta.requiresAuth && !isLoggedIn) {
        next({ path: '/login' })
      } else {
        next()
      }
    })

    await router.push('/welcome')
    await router.isReady()
    expect(router.currentRoute.value.path).toBe('/login')
  })

  it('allows authenticated user to access protected route', async () => {
    localStorage.setItem('isLoggedIn', 'true')
    const router = buildRouter()
    router.beforeEach((to, _from, next) => {
      const isLoggedIn = localStorage.getItem('isLoggedIn') === 'true'
      if (to.meta.requiresAuth && !isLoggedIn) {
        next({ path: '/login' })
      } else {
        next()
      }
    })

    await router.push('/welcome')
    await router.isReady()
    expect(router.currentRoute.value.path).toBe('/welcome')
  })

  it('allows unauthenticated access to /login', async () => {
    const router = buildRouter()
    router.beforeEach((to, _from, next) => {
      const isLoggedIn = localStorage.getItem('isLoggedIn') === 'true'
      if (to.meta.requiresAuth && !isLoggedIn) {
        next({ path: '/login' })
      } else {
        next()
      }
    })

    await router.push('/login')
    await router.isReady()
    expect(router.currentRoute.value.path).toBe('/login')
  })

  it('root path redirects to /login', async () => {
    const router = buildRouter()
    router.beforeEach((to, _from, next) => {
      const isLoggedIn = localStorage.getItem('isLoggedIn') === 'true'
      if (to.meta.requiresAuth && !isLoggedIn) {
        next({ path: '/login' })
      } else {
        next()
      }
    })

    await router.push('/')
    await router.isReady()
    expect(router.currentRoute.value.path).toBe('/login')
  })
})