From d71b44d606cc4ec771c693b81703a05ef78621a0 Mon Sep 17 00:00:00 2001
From: Jerel Miller <jerelmiller@gmail.com>
Date: Wed, 14 Oct 2020 16:05:46 -0700
Subject: [PATCH] feat: add syntax highlighting to terminal commands

---
 src/components/Terminal/SyntaxHighlighter.js | 127 +++++++++++++++++++
 src/components/Terminal/Terminal.js          |  41 +-----
 2 files changed, 129 insertions(+), 39 deletions(-)
 create mode 100644 src/components/Terminal/SyntaxHighlighter.js

diff --git a/src/components/Terminal/SyntaxHighlighter.js b/src/components/Terminal/SyntaxHighlighter.js
new file mode 100644
index 000000000..2afeddd66
--- /dev/null
+++ b/src/components/Terminal/SyntaxHighlighter.js
@@ -0,0 +1,127 @@
+import React from 'react';
+import PropTypes from 'prop-types';
+import { css } from '@emotion/core';
+import Highlight from 'prism-react-renderer';
+import Prism from 'prismjs';
+
+const WHITESPACE = /^\s*$/;
+const MULTILINE_COMMAND = /\\\s*$/;
+
+const SyntaxHighlighter = ({ code }) => (
+  <Highlight Prism={Prism} code={code} language="shell">
+    {({ tokens, getLineProps, getTokenProps }) => (
+      <pre
+        css={css`
+          ${nordTheme};
+
+          color: var(--color-nord-6);
+          display: block;
+          overflow: auto;
+          white-space: pre;
+          word-spacing: normal;
+          word-break: normal;
+          tab-size: 2;
+          hyphens: none;
+          text-shadow: none;
+
+          .token-line {
+            display: grid;
+            grid-template-columns: 1ch 1fr;
+            grid-gap: 1rem;
+          }
+        `}
+      >
+        <code
+          css={css`
+            display: table;
+            width: 100%;
+            padding: 0;
+            background: none;
+          `}
+        >
+          {tokens.map((line, idx) => {
+            const previousLine = collapse(tokens[idx - 1] || [])
+              .map((token) => token.content)
+              .join(' ');
+            const isMultiline = MULTILINE_COMMAND.test(previousLine);
+
+            return (
+              // eslint-disable-next-line react/jsx-key
+              <div {...getLineProps({ line, key: idx })}>
+                <div
+                  css={css`
+                    display: grid;
+                    grid-template-columns: 1ch 1fr;
+                    grid-gap: 1ch;
+                  `}
+                >
+                  <span
+                    css={css`
+                      color: var(--color-nord-10);
+                      user-select: none;
+                    `}
+                  >
+                    {isMultiline ? '>' : '$'}
+                  </span>
+                  <div
+                    css={css`
+                      color: #fafafa;
+                      white-space: pre;
+                    `}
+                  >
+                    {line.map((token, key) => (
+                      // eslint-disable-next-line react/jsx-key
+                      <span {...getTokenProps({ token, key })} />
+                    ))}
+                  </div>
+                </div>
+              </div>
+            );
+          })}
+        </code>
+      </pre>
+    )}
+  </Highlight>
+);
+
+const nordTheme = css`
+  .namespace {
+    opacity: 0.7;
+  }
+  .token {
+    &.plain:empty {
+      display: inline-block;
+    }
+
+    &.comment {
+      color: var(--color-nord-3);
+    }
+
+    &.punctuation,
+    &.operator {
+      color: var(--color-nord-9);
+    }
+
+    &.constant {
+      color: var(--color-nord-15);
+    }
+
+    &.string {
+      color: var(--color-nord-14);
+    }
+  }
+`;
+
+const collapse = (line) => {
+  return line.filter(
+    (token) =>
+      !WHITESPACE.test(token.content) && !token.types.includes('comment')
+  );
+};
+
+SyntaxHighlighter.propTypes = {
+  className: PropTypes.string,
+  code: PropTypes.string.isRequired,
+};
+
+export default SyntaxHighlighter;
diff --git a/src/components/Terminal/Terminal.js b/src/components/Terminal/Terminal.js
index 0c063d298..3e68c1ba5 100644
--- a/src/components/Terminal/Terminal.js
+++ b/src/components/Terminal/Terminal.js
@@ -2,8 +2,7 @@ import React from 'react';
 import PropTypes from 'prop-types';
 import { css } from '@emotion/core';
 import { Button, useClipboard } from '@newrelic/gatsby-theme-newrelic';
-
-const MULTILINE_COMMAND = /\\\s*$/;
+import SyntaxHighlighter from './SyntaxHighlighter';
 
 const Terminal = ({ children }) => {
   const [copied, copy] = useClipboard();
@@ -66,17 +65,7 @@ const Terminal = ({ children }) => {
           border-bottom-right-radius: var(--border-radius);
         `}
       >
-        {children
-          .trim()
-          .split('\n')
-          .map((line, idx, lines) => (
-            <Line
-              key={idx}
-              multiline={MULTILINE_COMMAND.test(lines[idx - 1] || '')}
-            >
-              {line}
-            </Line>
-          ))}
+        <SyntaxHighlighter code={children.trim()} />
       </div>
     </div>
   );
@@ -97,32 +86,6 @@ FrameButton.propTypes = {
   color: PropTypes.string,
 };
 
-const Line = ({ children, multiline }) => (
-  <div
-    css={css`
-      display: flex;
-    `}
-  >
-    <span
-      css={css`
-        color: var(--color-nord-10);
-        user-select: none;
-        margin-right: 1ch;
-      `}
-    >
-      {multiline ? '>' : '$'}
-    </span>
-    <div
-      css={css`
-        color: #fafafa;
-        white-space: pre;
-      `}
-    >
-      {children}
-    </div>
-  </div>
-);
-
 Terminal.propTypes = {
   children: PropTypes.string,
 };