import { getPageStyle } from '@/utils/page-style'
import { View, Text, Button, Checkbox, CheckboxGroup, Image } from '@tarojs/components'
import { useEffect, useState } from 'react'
import Taro from '@tarojs/taro'
import { getToken, wechatLogin } from '@/services/auth'
import './index.scss'

const LOGIN_PAGE_URL = '/pages/login/index'
const DEFAULT_POST_LOGIN_URL = '/pages/device/index'
const TAB_BAR_ROUTES = new Set([
  '/pages/device/index',
  '/pages/chat/index',
  '/pages/location/index',
  '/pages/sleep/index',
])

function consumePostLoginRedirect(): string {
  const storedUrl = String(Taro.getStorageSync('postLoginRedirect') || '').trim()
  Taro.removeStorageSync('postLoginRedirect')

  if (!storedUrl || storedUrl === LOGIN_PAGE_URL || !storedUrl.startsWith('/pages/')) {
    return DEFAULT_POST_LOGIN_URL
  }

  return storedUrl
}

function navigateAfterLogin(url: string): void {
  const route = url.split('?')[0]
  if (!TAB_BAR_ROUTES.has(route)) {
    Taro.reLaunch({ url })
    return
  }

  // Tab pages must be opened with switchTab so their lifecycle and custom tab bar refresh.
  void Promise.resolve(Taro.switchTab({ url: route })).catch(() => {
    Taro.reLaunch({ url: route })
  })
}

export default function Login() {
  const [submitting, setSubmitting] = useState(false)
  const [agreementAccepted, setAgreementAccepted] = useState(false)

  useEffect(() => {
    if (getToken()) {
      navigateAfterLogin(consumePostLoginRedirect())
      return
    }

  }, [])

  const handleLogin = async () => {
    if (submitting) return
    if (!agreementAccepted) {
      Taro.showToast({
        title: '请先阅读并同意协议',
        icon: 'none',
      })
      return
    }

    setSubmitting(true)
    Taro.showLoading({ title: '登录中...' })

    try {
      const loginRes = await Taro.login()
      if (!loginRes.code) {
        throw new Error('未获取到微信登录凭证')
      }

      const session = await wechatLogin({
        code: loginRes.code,
      })

      const nextUserInfo = {
        nickname: session.nickname || '',
      }

      if (nextUserInfo.nickname) {
        Taro.setStorageSync('userInfo', {
          nickname: nextUserInfo.nickname,
        })
      } else {
        Taro.removeStorageSync('userInfo')
      }

      Taro.showToast({ title: '登录成功', icon: 'success' })
      setTimeout(() => {
        navigateAfterLogin(consumePostLoginRedirect())
      }, 300)
    } catch (error: any) {
      console.error('[login] failed:', error)
      const message = String(error?.message || '登录失败，请重试')
      Taro.showModal({
        title: '登录失败',
        content: message,
        showCancel: false,
      })
    } finally {
      Taro.hideLoading()
      setSubmitting(false)
    }
  }

  const handleGuestBrowse = () => {
    Taro.removeStorageSync('postLoginRedirect')
    Taro.reLaunch({ url: '/pages/device/index' })
  }

  const handleAgreementChange = (event) => {
    const values = event.detail.value || []
    setAgreementAccepted(values.includes('accepted'))
  }

  const openUserAgreement = () => {
    Taro.showModal({
      title: '用户服务协议',
      content: '欢迎使用伴伴。您在使用本小程序前，应阅读并同意本协议。我们将为您提供设备绑定、状态查看、消息互动、定位展示等服务。请您遵守法律法规，不得利用本服务从事违法或侵犯他人权益的行为。',
      showCancel: false,
      confirmText: '我知道了',
    })
  }

  const openPrivacyPolicy = () => {
    const taroWithPrivacy = Taro as typeof Taro & {
      openPrivacyContract?: (option?: {
        success?: () => void
        fail?: (error: unknown) => void
      }) => void
    }

    if (typeof taroWithPrivacy.openPrivacyContract === 'function') {
      taroWithPrivacy.openPrivacyContract({
        fail: () => {
          Taro.showModal({
            title: '隐私政策',
            content: '暂时无法打开隐私保护指引，请稍后重试。',
            showCancel: false,
            confirmText: '我知道了',
          })
        },
      })
      return
    }

    Taro.showModal({
      title: '隐私政策',
      content: '伴伴会在提供设备绑定、消息互动、定位展示等功能时，按需处理您的账号信息、设备信息和位置信息。我们仅在实现相关功能所必需的范围内使用上述信息。',
      showCancel: false,
      confirmText: '我知道了',
    })
  }

  return (
    <View className='login-page' style={getPageStyle(false)}>
      <View className='login-header'>
        <View className='logo'>
          <Image
            className='login-hero-art'
            src={require('../../assets/ui/login-hero.png')}
            mode='aspectFit'
          />
        </View>
        <Text className='title'>伴伴</Text>
        <Text className='subtitle'>让关爱随时随地</Text>
      </View>

      <View className='login-content'>
        <View className='features'>
          <View className='feature-item'>
            <Image className='feature-icon-image' src={require('../../assets/ui/feature-chat.png')} mode='aspectFit' />
            <Text className='feature-text'>AI 智能对话</Text>
          </View>
          <View className='feature-item'>
            <Image className='feature-icon-image' src={require('../../assets/ui/feature-location.png')} mode='aspectFit' />
            <Text className='feature-text'>实时定位追踪</Text>
          </View>
          <View className='feature-item'>
            <Image className='feature-icon-image' src={require('../../assets/ui/feature-status.png')} mode='aspectFit' />
            <Text className='feature-text'>设备状态监控</Text>
          </View>
        </View>

        <View className='login-info-card'>
          <Text className='login-info-title'>登录后启用设备管理</Text>
          <Text className='login-info-desc'>仅在绑定设备、查看定位和管理宝贝资料时需要登录。</Text>
        </View>

        <View className='login-btn-wrapper'>
          <Button className='login-btn' loading={submitting} disabled={submitting} onClick={handleLogin}>
            <Text className='btn-icon'>🌐</Text>
            <Text className='btn-text'>{submitting ? '登录中...' : '登录后继续'}</Text>
          </Button>
          <View className='guest-browse-btn' onClick={handleGuestBrowse}>
            <Text className='guest-browse-text'>暂不登录，先浏览</Text>
          </View>
        </View>

        <View className='agreement-panel'>
          <CheckboxGroup value={agreementAccepted ? ['accepted'] : []} onChange={handleAgreementChange}>
            <View className='agreement-row'>
              <Checkbox className='agreement-checkbox' value='accepted' checked={agreementAccepted} color='#07C160' />
              <View className='agreement-text-wrap'>
                <Text className='agreement-text'>我已阅读并同意</Text>
                <Text className='agreement-link' onClick={openUserAgreement}>《用户服务协议》</Text>
                <Text className='agreement-text'>和</Text>
                <Text className='agreement-link' onClick={openPrivacyPolicy}>《隐私政策》</Text>
              </View>
            </View>
          </CheckboxGroup>
        </View>
      </View>
    </View>
  )
}