/**
 * 移动端交互优化工具
 */

// 检测移动设备
export const isMobileDevice = () => {
  return /Android|webOS|iPhone|iPad|iPod|BlackBerry|IEMobile|Opera Mini/i.test(navigator.userAgent)
}

// 检测触摸设备
export const isTouchDevice = () => {
  return 'ontouchstart' in window || navigator.maxTouchPoints > 0 || navigator.msMaxTouchPoints > 0
}

// 检测设备方向
export const getOrientation = () => {
  return window.innerWidth > window.innerHeight ? 'landscape' : 'portrait'
}

// 监听方向变化
export const onOrientationChange = (callback) => {
  let orientation = getOrientation()
  
  const handleResize = () => {
    const newOrientation = getOrientation()
    if (newOrientation !== orientation) {
      orientation = newOrientation
      callback(newOrientation)
    }
  }

  window.addEventListener('resize', handleResize)
  
  return () => {
    window.removeEventListener('resize', handleResize)
  }
}

// 防止iOS缩放
export const preventIOSZoom = () => {
  let lastTouchEnd = 0
  
  const preventZoom = (e) => {
    const now = Date.now()
    if (now - lastTouchEnd <= 300) {
      e.preventDefault()
    }
    lastTouchEnd = now
  }

  document.addEventListener('touchend', preventZoom, { passive: false })
  
  return () => {
    document.removeEventListener('touchend', preventZoom)
  }
}

// 添加触摸反馈
export const addTouchFeedback = (element, options = {}) => {
  const {
    className = 'touch-feedback',
    duration = 150,
    scale = 0.98
  } = options

  if (!element) return

  const style = document.createElement('style')
  style.textContent = `
    .${className} {
      transform: scale(${scale});
      transition: transform ${duration}ms ease;
    }
  `
  document.head.appendChild(style)

  const addFeedback = () => {
    element.classList.add(className)
    setTimeout(() => {
      element.classList.remove(className)
    }, duration)
  }

  element.addEventListener('touchstart', addFeedback, { passive: true })
  
  return () => {
    element.removeEventListener('touchstart', addFeedback)
    if (style.parentNode) {
      style.parentNode.removeChild(style)
    }
  }
}

// 滚动到顶部
export const scrollToTop = (smooth = true) => {
  window.scrollTo({
    top: 0,
    behavior: smooth ? 'smooth' : 'auto'
  })
}

// 滚动到元素
export const scrollToElement = (element, options = {}) => {
  const {
    behavior = 'smooth',
    block = 'start',
    inline = 'nearest',
    offset = 0
  } = options

  if (!element) return

  const elementTop = element.offsetTop + offset
  
  window.scrollTo({
    top: elementTop,
    behavior
  })
}

// 获取安全区域
export const getSafeArea = () => {
  const style = getComputedStyle(document.documentElement)
  
  return {
    top: parseInt(style.getPropertyValue('env(safe-area-inset-top)')) || 0,
    right: parseInt(style.getPropertyValue('env(safe-area-inset-right)')) || 0,
    bottom: parseInt(style.getPropertyValue('env(safe-area-inset-bottom)')) || 0,
    left: parseInt(style.getPropertyValue('env(safe-area-inset-left)')) || 0
  }
}

// 处理键盘弹起
export const handleVirtualKeyboard = () => {
  let initialViewportHeight = window.innerHeight
  
  const handleResize = () => {
    const currentHeight = window.innerHeight
    const heightDifference = initialViewportHeight - currentHeight
    
    // 键盘弹起时的处理（高度差超过150px认为是键盘弹起）
    if (heightDifference > 150) {
      document.body.classList.add('keyboard-open')
      document.body.style.height = `${currentHeight}px`
    } else {
      document.body.classList.remove('keyboard-open')
      document.body.style.height = ''
    }
  }

  window.addEventListener('resize', handleResize)
  
  return () => {
    window.removeEventListener('resize', handleResize)
    document.body.classList.remove('keyboard-open')
    document.body.style.height = ''
  }
}

// 防抖函数
export const debounce = (func, wait) => {
  let timeout
  return function executedFunction(...args) {
    const later = () => {
      clearTimeout(timeout)
      func(...args)
    }
    clearTimeout(timeout)
    timeout = setTimeout(later, wait)
  }
}

// 节流函数
export const throttle = (func, limit) => {
  let inThrottle
  return function(...args) {
    if (!inThrottle) {
      func.apply(this, args)
      inThrottle = true
      setTimeout(() => inThrottle = false, limit)
    }
  }
}

// 复制到剪贴板
export const copyToClipboard = async (text) => {
  try {
    if (navigator.clipboard && window.isSecureContext) {
      await navigator.clipboard.writeText(text)
      return true
    } else {
      // 降级方案
      const textArea = document.createElement('textarea')
      textArea.value = text
      textArea.style.position = 'fixed'
      textArea.style.left = '-999999px'
      textArea.style.top = '-999999px'
      document.body.appendChild(textArea)
      textArea.focus()
      textArea.select()
      
      try {
        document.execCommand('copy')
        return true
      } catch (err) {
        console.error('复制失败:', err)
        return false
      } finally {
        textArea.remove()
      }
    }
  } catch (err) {
    console.error('复制失败:', err)
    return false
  }
}

// 震动反馈
export const vibrate = (pattern = 50) => {
  if ('vibrate' in navigator) {
    navigator.vibrate(pattern)
  }
}

// 全屏显示
export const requestFullscreen = (element = document.documentElement) => {
  if (element.requestFullscreen) {
    return element.requestFullscreen()
  } else if (element.webkitRequestFullscreen) {
    return element.webkitRequestFullscreen()
  } else if (element.msRequestFullscreen) {
    return element.msRequestFullscreen()
  }
}

// 退出全屏
export const exitFullscreen = () => {
  if (document.exitFullscreen) {
    return document.exitFullscreen()
  } else if (document.webkitExitFullscreen) {
    return document.webkitExitFullscreen()
  } else if (document.msExitFullscreen) {
    return document.msExitFullscreen()
  }
}

// 检测网络状态
export const getNetworkStatus = () => {
  if ('connection' in navigator) {
    const connection = navigator.connection
    return {
      online: navigator.onLine,
      effectiveType: connection.effectiveType,
      downlink: connection.downlink,
      rtt: connection.rtt,
      saveData: connection.saveData
    }
  }
  
  return {
    online: navigator.onLine
  }
}

// 监听网络变化
export const onNetworkChange = (callback) => {
  const handleOnline = () => callback({ online: true })
  const handleOffline = () => callback({ online: false })
  
  window.addEventListener('online', handleOnline)
  window.addEventListener('offline', handleOffline)
  
  return () => {
    window.removeEventListener('online', handleOnline)
    window.removeEventListener('offline', handleOffline)
  }
}

// PWA安装提示
export const handlePWAInstall = () => {
  let deferredPrompt
  
  const beforeInstallPrompt = (e) => {
    e.preventDefault()
    deferredPrompt = e
  }
  
  const showInstallPrompt = async () => {
    if (deferredPrompt) {
      deferredPrompt.prompt()
      const { outcome } = await deferredPrompt.userChoice
      deferredPrompt = null
      return outcome === 'accepted'
    }
    return false
  }
  
  window.addEventListener('beforeinstallprompt', beforeInstallPrompt)
  
  return {
    showInstallPrompt,
    cleanup: () => {
      window.removeEventListener('beforeinstallprompt', beforeInstallPrompt)
    }
  }
}

export default {
  isMobileDevice,
  isTouchDevice,
  getOrientation,
  onOrientationChange,
  preventIOSZoom,
  addTouchFeedback,
  scrollToTop,
  scrollToElement,
  getSafeArea,
  handleVirtualKeyboard,
  debounce,
  throttle,
  copyToClipboard,
  vibrate,
  requestFullscreen,
  exitFullscreen,
  getNetworkStatus,
  onNetworkChange,
  handlePWAInstall
}