// 写入剪贴板；Clipboard API 只在 HTTPS/localhost 可用，局域网 HTTP 访问时退回 execCommand
export async function copyText(text: string): Promise<boolean> {
  if (navigator.clipboard && window.isSecureContext) {
    try {
      await navigator.clipboard.writeText(text)
      return true
    } catch {
      // 权限被拒时继续尝试旧方法
    }
  }
  const ta = document.createElement('textarea')
  ta.value = text
  ta.style.cssText = 'position:fixed;top:0;left:0;opacity:0'
  document.body.append(ta)
  ta.select()
  const ok = document.execCommand('copy')
  ta.remove()
  return ok
}