From 6799a07a39623eb213b261ddf3b72900b47c62c5 Mon Sep 17 00:00:00 2001
From: v1rtl <hi@v1rtl.site>
Date: Fri, 27 Sep 2024 16:05:14 +0300
Subject: [PATCH] feat: dark theme support in docs

---
 .../atoms/ThemeProvider/ThemeProvider.tsx     |  9 ++--
 docs/src/components/SideBar.tsx               | 41 +++++++++--------
 docs/src/pages/_app.tsx                       | 16 ++++++-
 docs/src/pages/_document.tsx                  | 45 +++++++++++++++++++
 4 files changed, 88 insertions(+), 23 deletions(-)
 create mode 100644 docs/src/pages/_document.tsx

diff --git a/components/src/components/atoms/ThemeProvider/ThemeProvider.tsx b/components/src/components/atoms/ThemeProvider/ThemeProvider.tsx
index fddd2cc0..62238d3b 100644
--- a/components/src/components/atoms/ThemeProvider/ThemeProvider.tsx
+++ b/components/src/components/atoms/ThemeProvider/ThemeProvider.tsx
@@ -11,9 +11,12 @@ const ThemeContext = React.createContext<ThemeContextValue | null>(null)
 
 type Props = {
   defaultMode?: Mode
+  onThemeChange?: (mode: Mode) => void
 }
+
 export const ThemeProvider: React.FC<React.PropsWithChildren<Props>> = ({
   defaultMode = 'light',
+  onThemeChange,
   children,
 }) => {
   const [mode, setMode] = React.useState<Mode>(defaultMode)
@@ -21,11 +24,9 @@ export const ThemeProvider: React.FC<React.PropsWithChildren<Props>> = ({
   const value = React.useMemo(() => ({ mode, setMode }), [mode])
 
   React.useEffect(() => {
-    const root = document.querySelector(':root')
-    if (root) {
-      root.setAttribute('data-theme', mode)
-    }
+    if (onThemeChange) onThemeChange(mode)
   }, [mode])
+
   return <ThemeContext.Provider value={value}>{children}</ThemeContext.Provider>
 }
 
diff --git a/docs/src/components/SideBar.tsx b/docs/src/components/SideBar.tsx
index ae82e134..84127b0a 100644
--- a/docs/src/components/SideBar.tsx
+++ b/docs/src/components/SideBar.tsx
@@ -12,7 +12,7 @@ import {
   useTheme,
 } from '@ensdomains/thorin'
 import { Link } from './Link'
-import type { PropsWithChildren } from 'react'
+import { type PropsWithChildren } from 'react'
 import { useRouter } from 'next/router'
 
 type Link = { name: string, route: string }
@@ -63,6 +63,7 @@ const Divider = () => (
 export const SideBar = ({ open, links }: { open: boolean, links: Links }) => {
   const router = useRouter()
   const { setMode, mode } = useTheme()
+
   return (
     <Box
       display="flex"
@@ -81,23 +82,27 @@ export const SideBar = ({ open, links }: { open: boolean, links: Links }) => {
     >
       <ScrollBox width="full" hideDividers>
         <Box padding="4" display="flex" flexDirection="column" gap="4">
-          <Field
-            label={(
-              <Box height="6.5" display="flex" alignItems="center">
-                {mode === 'light' ? 'Light Theme' : 'Dark Theme'}
-              </Box>
-            )}
-            inline
-          >
-            <ThemeToggle
-              size="extraSmall"
-              checked={mode === 'light'}
-              onChange={(e) => {
-                const newValue = e.target.checked ? 'light' : 'dark'
-                if (newValue !== mode) setMode(newValue)
-              }}
-            />
-          </Field>
+          {typeof window !== 'undefined' && (
+            <Field
+              label={(
+                <Box height="6.5" display="flex" alignItems="center">
+                  {mode === 'light' ? 'Light Theme' : 'Dark Theme'}
+                </Box>
+              )}
+              inline
+            >
+              <ThemeToggle
+                size="extraSmall"
+                checked={mode === 'light'}
+                onChange={(e) => {
+                  const newValue = e.target.checked ? 'light' : 'dark'
+                  if (newValue !== mode) {
+                    setMode(newValue)
+                  }
+                }}
+              />
+            </Field>
+          )}
           <Divider />
           <Box>
             <Heading icon={<StarSVG />}>Getting Started</Heading>
diff --git a/docs/src/pages/_app.tsx b/docs/src/pages/_app.tsx
index 48db18b7..736873f5 100644
--- a/docs/src/pages/_app.tsx
+++ b/docs/src/pages/_app.tsx
@@ -2,6 +2,7 @@ import * as React from 'react'
 import type { AppProps } from 'next/app'
 import { MDXProvider } from '@mdx-js/react'
 
+import type { Mode } from '@ensdomains/thorin'
 import { ThemeProvider } from '@ensdomains/thorin'
 import '@ensdomains/thorin/dist/style.css'
 import { MDX } from '~/components'
@@ -10,6 +11,14 @@ import '~/styles/globalStyles.css'
 import '../styles/styles.css'
 import type { GetLayout, NextComponentType } from 'next'
 
+declare global {
+  interface Window {
+    __theme: Mode
+    __setPreferredTheme: (theme: Mode) => void
+    __onThemeChange: (theme: Mode) => void
+  }
+}
+
 const App = ({ Component, pageProps }: AppProps) => {
   const getLayout = (Component as NextComponentType & { getLayout: GetLayout }).getLayout || getDocsLayout
 
@@ -18,7 +27,12 @@ const App = ({ Component, pageProps }: AppProps) => {
       {/* <Head /> */}
       {/* Prevent theme flash */}
       <MDXProvider components={MDX}>
-        <ThemeProvider>{getLayout(<Component {...pageProps} />)}</ThemeProvider>
+        <ThemeProvider
+          onThemeChange={mode => window.__setPreferredTheme(mode)}
+          defaultMode={typeof window !== 'undefined' ? window.__theme : 'light'}
+        >
+          {getLayout(<Component {...pageProps} />)}
+        </ThemeProvider>
       </MDXProvider>
     </>
   )
diff --git a/docs/src/pages/_document.tsx b/docs/src/pages/_document.tsx
new file mode 100644
index 00000000..d594ab9c
--- /dev/null
+++ b/docs/src/pages/_document.tsx
@@ -0,0 +1,45 @@
+/* eslint-disable @eslint-react/dom/no-dangerously-set-innerhtml */
+import { Html, Head, Main, NextScript } from 'next/document'
+
+export default function Document() {
+  return (
+    <Html>
+      <Head />
+      <body>
+        <script
+          dangerouslySetInnerHTML={{
+            __html: `(function () {
+    function setTheme(newTheme) {
+        document.documentElement.setAttribute('data-theme', newTheme);
+        window.__theme = newTheme;
+        window.__onThemeChange(newTheme);
+    }
+    window.__onThemeChange = function () {};
+    window.__setPreferredTheme = function (newTheme) {
+        setTheme(newTheme);
+        try {
+            localStorage.setItem("theme", JSON.stringify(window.__theme));
+        } catch (err) {}
+    };
+
+    const darkQuery = window.matchMedia("(prefers-color-scheme: dark)");
+    darkQuery.addListener(function (event) {
+        window.__setPreferredTheme(event.matches ? "dark" : "light");
+    });
+
+    let preferredTheme;
+    try {
+        preferredTheme = JSON.parse(localStorage.getItem("theme"));
+    } catch (err) {}
+    
+    setTheme(preferredTheme || (darkQuery.matches ? "dark" : "light"));
+})();
+            `,
+          }}
+        />
+        <Main />
+        <NextScript />
+      </body>
+    </Html>
+  )
+}