// plugins/smart-flexible.client.js

class ResponsiveAdapter {
    constructor() {
      this.isMobile = this.checkMobile()
      this.init()
    }
    
    checkMobile() {
      const ua = navigator.userAgent.toLowerCase()
      const mobileKeywords = [
        'iphone', 'ipod', 'android.*mobile',
        'windows.*phone', 'blackberry.*mobile',
        'mobile', 'tablet'
      ]
      
      const isMobileUA = mobileKeywords.some(keyword => 
        new RegExp(keyword).test(ua)
      )
      
      const screenWidth = window.innerWidth
      const isSmallScreen = screenWidth <= 768
      
      return isMobileUA || isSmallScreen
    }
    
    init() {
      const docEl = document.documentElement
      
      if (this.isMobile) {
        // 移动端逻辑
        this.initMobile(docEl)
      } else {
        // PC 端逻辑
        this.initPC(docEl)
      }
      
      // 添加设备标识类
      this.addDeviceClass(docEl)
      
      // 监听窗口变化
      window.addEventListener('resize', () => {
        this.handleResize(docEl)
      })
    }
    
    initMobile(docEl) {
      const dpr = window.devicePixelRatio || 1
      
      // 设置 viewport meta
      this.setViewport(dpr)
      
      // 设置 rem
      const setRem = () => {
        const rem = docEl.clientWidth / 10
        docEl.style.fontSize = rem + 'px'
      }
      
      setRem()
      window.addEventListener('resize', setRem)
      
      // 存储方法供外部调用
      this.setRem = setRem
    }
    
    initPC(docEl) {
      // PC 端使用响应式 rem
      const setPCRem = () => {
        const width = docEl.clientWidth
        
        // 响应式断点
        let fontSize
        if (width >= 1920) {
          fontSize = 192 // 1920/10
        } else if (width >= 1600) {
          fontSize = 160 // 1600/10
        } else if (width >= 1440) {
          fontSize = 144 // 1440/10
        } else if (width >= 1366) {
          fontSize = 136.6 // 1366/10
        } else if (width >= 1200) {
          fontSize = 120 // 1200/10
        } else {
          fontSize = 100 // 小于1200时的基准
        }
        
        docEl.style.fontSize = fontSize + 'px'
      }
      
      setPCRem()
      window.addEventListener('resize', setPCRem)
      
      this.setPCRem = setPCRem
    }
    
    setViewport(dpr) {
      let viewport = document.querySelector('meta[name="viewport"]')
      if (!viewport) {
        viewport = document.createElement('meta')
        viewport.name = 'viewport'
        document.head.appendChild(viewport)
      }
      
      if (this.isMobile) {
        viewport.content = `width=device-width, initial-scale=${1/dpr}, maximum-scale=${1/dpr}, minimum-scale=${1/dpr}, user-scalable=no`
      } else {
        viewport.content = 'width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no'
      }
    }
    
    addDeviceClass(docEl) {
      docEl.classList.remove('is-pc', 'is-mobile')
      docEl.classList.add(this.isMobile ? 'is-mobile' : 'is-pc')
    }
    
    handleResize(docEl) {
      const wasMobile = this.isMobile
      this.isMobile = this.checkMobile()
      
      if (wasMobile !== this.isMobile) {
        // 设备类型发生变化
        this.addDeviceClass(docEl)
        if (this.isMobile) {
          this.initMobile(docEl)
        } else {
          this.initPC(docEl)
        }
      } else {
        // 同设备类型，只更新 rem
        if (this.isMobile && this.setRem) {
          this.setRem()
        } else if (!this.isMobile && this.setPCRem) {
          this.setPCRem()
        }
      }
    }
  }
  
  // 初始化
  export default defineNuxtPlugin(() => {
    if (process.client) {
      new ResponsiveAdapter()
    }
  })