feat: copy code button

components/MDXComponents.js

@@ -1,9 +1,11 @@
 import Image from 'next/image'
 import CustomLink from './Link'
+import Pre from './Pre'
 
 const MDXComponents = {
   Image,
   a: CustomLink,
+  pre: Pre,
 }
 
 export default MDXComponents

components/Pre.js

@@ -0,0 +1,70 @@
+import { useState, useRef } from 'react'
+
+const Pre = (props) => {
+  const textInput = useRef(null)
+  const [hovered, setHovered] = useState(false)
+  const [copied, setCopied] = useState(false)
+
+  const onEnter = () => {
+    setHovered(true)
+  }
+  const onExit = () => {
+    setHovered(false)
+    setCopied(false)
+  }
+  const onCopy = () => {
+    setCopied(true)
+    navigator.clipboard.writeText(textInput.current.textContent)
+    setTimeout(() => {
+      setCopied(false)
+    }, 2000)
+  }
+
+  return (
+    <pre ref={textInput} onMouseEnter={onEnter} onMouseLeave={onExit} className="relative">
+      {hovered && (
+        <button
+          aria-label="Copy code"
+          type="button"
+          className={`absolute right-3 w-8 h-8 p-1 rounded border-2 bg-gray-700 dark:bg-gray-800 ${
+            copied
+              ? 'focus:outline-none focus:border-green-400 border-green-400'
+              : 'border-gray-300'
+          }`}
+          onClick={onCopy}
+        >
+          <svg
+            xmlns="http://www.w3.org/2000/svg"
+            viewBox="0 0 24 24"
+            stroke="currentColor"
+            fill="none"
+            className={copied ? 'text-green-400' : 'text-gray-300'}
+          >
+            {copied ? (
+              <>
+                <path
+                  strokeLinecap="round"
+                  strokeLinejoin="round"
+                  strokeWidth={2}
+                  d="M9 5H7a2 2 0 00-2 2v12a2 2 0 002 2h10a2 2 0 002-2V7a2 2 0 00-2-2h-2M9 5a2 2 0 002 2h2a2 2 0 002-2M9 5a2 2 0 012-2h2a2 2 0 012 2m-6 9l2 2 4-4"
+                />
+              </>
+            ) : (
+              <>
+                <path
+                  strokeLinecap="round"
+                  strokeLinejoin="round"
+                  strokeWidth={2}
+                  d="M9 5H7a2 2 0 00-2 2v12a2 2 0 002 2h10a2 2 0 002-2V7a2 2 0 00-2-2h-2M9 5a2 2 0 002 2h2a2 2 0 002-2M9 5a2 2 0 012-2h2a2 2 0 012 2"
+                />
+              </>
+            )}
+          </svg>
+        </button>
+      )}
+      {props.children}
+    </pre>
+  )
+}
+
+export default Pre