display svg images in code blocks

app/public/index.html

@@ -30,7 +30,7 @@
   <link href="https://fonts.googleapis.com/css?family=Work+Sans:300,400,500,600,700&display=swap" rel="stylesheet">
   <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/katex@0.16.0/dist/katex.min.css"
     integrity="sha384-Xi8rHCmBmhbuyyhbI88391ZKP2dmfnOl4rT9ZfRI7mLTdk1wblIUnrIq35nqwEvC" crossorigin="anonymous">
-  <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/@tailwindcss/typography@0.4.1/dist/typography.min.css" />
+  <link rel="stylesheet" href="/prose.css" />
   <style>
     body {
       background: #292933;

app/src/components/markdown.tsx

@@ -1,3 +1,4 @@
+import styled from '@emotion/styled';
 import ReactMarkdown from 'react-markdown';
 import { Prism as SyntaxHighlighter } from 'react-syntax-highlighter';
 import { vscDarkPlus } from 'react-syntax-highlighter/dist/esm/styles/prism';
@@ -8,6 +9,47 @@ import { Button, CopyButton } from '@mantine/core';
 import { useMemo } from 'react';
 import { FormattedMessage, useIntl } from 'react-intl';
 
+const Code = styled.div`
+    padding: 0;
+    border-radius: 0.25rem;
+    overflow: hidden;
+
+    &>div {
+        margin: 0 !important;
+    }
+
+    .fa {
+        font-style: normal !important;
+    }
+`;
+
+const Header = styled.div`
+    display: flex;
+    align-items: center;
+    justify-content: flex-end;
+    background: #191919;
+    height: 2.5rem;
+    padding: 0.1rem 0.1rem 0 0.5rem;
+
+    .mantine-Button-label {
+        display: flex;
+        align-items: center;
+
+        * {
+            font-size: 90%;
+        }
+    }
+`;
+
+const ImagePreview = styled.div`
+    text-align: center;
+
+    img {
+        max-width: 100%;
+        display: block;
+    }
+`;
+
 export interface MarkdownProps {
     content: string;
     className?: string;
@@ -28,14 +70,30 @@ export function Markdown(props: MarkdownProps) {
 
     const elem = useMemo(() => (
         <div className={classes.join(' ')}>
-            <ReactMarkdown remarkPlugins={[remarkGfm, remarkMath]}
+            <ReactMarkdown
+                remarkPlugins={[remarkGfm, remarkMath]}
                 rehypePlugins={[rehypeKatex]}
                 components={{
                     code({ node, inline, className, children, ...props }) {
                         const match = /language-(\w+)/.exec(className || '')
-                        return !inline ? (
-                            <div>
-                                <CopyButton value={String(children)}>
+                        const code = String(children);
+                        return !inline ? (<>
+                            <Code>
+                                <Header>
+                                    {code.startsWith('<svg') && code.includes('</svg>') && (
+                                        <Button variant="subtle" size="sm" compact onClick={() => {
+                                            const blob = new Blob([code], { type: 'image/svg+xml' });
+                                            const url = URL.createObjectURL(blob);
+                                            const a = document.createElement('a');
+                                            a.href = url;
+                                            a.download = 'image.svg';
+                                            a.click();
+                                        }}>
+                                            <i className="fa fa-download" />
+                                            <span><FormattedMessage defaultMessage="Download SVG" /></span>
+                                        </Button>
+                                    )}
+                                    <CopyButton value={code}>
                                         {({ copy, copied }) => (
                                             <Button variant="subtle" size="sm" compact onClick={copy}>
                                                 <i className="fa fa-clipboard" />
@@ -43,15 +101,20 @@ export function Markdown(props: MarkdownProps) {
                                             </Button>
                                         )}
                                     </CopyButton>
+                                </Header>
                                 <SyntaxHighlighter
-                                    children={String(children).replace(/\n$/, '')}
+                                    children={code}
                                     style={vscDarkPlus as any}
                                     language={match?.[1] || 'text'}
                                     PreTag="div"
-                                    {...props}
-                                />
-                            </div>
-                        ) : (
+                                    {...props} />
+                            </Code>
+                            {code.startsWith('<svg') && code.includes('</svg>') && (
+                                <ImagePreview>
+                                    <img src={`data:image/svg+xml;base64,${btoa(code)}`} />
+                                </ImagePreview>
+                            )}
+                        </>) : (
                             <code className={className} {...props}>
                                 {children}
                             </code>