✨(demo) add theme selector

As we aims to create several themes for this demo app, we add a select
to easily switch between all existing themes.

apps/demo/src/App.tsx

@@ -1,13 +1,24 @@
-import { Button, CunninghamProvider } from "@openfun/cunningham-react";
-import React, { useEffect, useState } from "react";
+import { Button, CunninghamProvider, Select } from "@openfun/cunningham-react";
+import React, { useEffect, useMemo, useState } from "react";
 import { Create } from "./Create";
 import { Home } from "./Home";
 
 enum Theme {
-  DEFAULT = "default",
+  CUNNINGHAM = "cunningham",
+}
+
+enum Variant {
+  LIGHT = "light",
   DARK = "dark",
 }
 
+const THEMES: Record<Theme, Record<Variant, string | undefined>> = {
+  [Theme.CUNNINGHAM]: {
+    light: "default",
+    dark: "dark",
+  },
+};
+
 export enum Page {
   HOME,
   CREATE,
@@ -19,15 +30,27 @@ export interface PageProps {
 
 const preferredScheme = window.matchMedia("(prefers-color-scheme: dark)")
   .matches
-  ? Theme.DARK
-  : Theme.DEFAULT;
+  ? { theme: Theme.CUNNINGHAM, variant: Variant.DARK }
+  : { theme: Theme.CUNNINGHAM, variant: Variant.LIGHT };
 
 export const App = () => {
   const [locale] = useState("en-US");
-  const [theme, setTheme] = useState<Theme>(preferredScheme);
+  const [theme, setTheme] = useState<Theme>(
+    (sessionStorage.getItem("c-theme") as Theme | null) ??
+      preferredScheme.theme,
+  );
+  const [variant, setVariant] = useState<Variant>(
+    (sessionStorage.getItem("c-variant") as Variant | null) ??
+      preferredScheme.variant,
+  );
+  const activeTheme = useMemo(() => THEMES[theme][variant], [theme, variant]);
   const [page, setPage] = useState<Page>(Page.HOME);
-  const handleThemeChange = (event: MediaQueryListEvent) =>
-    setTheme(event.matches ? Theme.DARK : Theme.DEFAULT);
+  const handleThemeChange = (event: MediaQueryListEvent) => {
+    const nextVariant = event.matches ? Variant.DARK : Variant.LIGHT;
+    if (THEMES[theme][nextVariant] !== undefined) {
+      setVariant(nextVariant);
+    }
+  };
 
   useEffect(() => {
     const query = window.matchMedia("(prefers-color-scheme: dark)");
@@ -38,31 +61,66 @@ export const App = () => {
     };
   }, []);
 
+  useEffect(() => {
+    document.documentElement.setAttribute("data-theme", theme);
+    document.documentElement.setAttribute("data-variant", variant);
+    sessionStorage.setItem("c-theme", theme);
+    sessionStorage.setItem("c-variant", variant);
+  }, [theme, variant]);
+
   return (
-    <CunninghamProvider currentLocale={locale} theme={theme}>
+    <CunninghamProvider currentLocale={locale} theme={activeTheme}>
       <div className="container">
+        {theme === Theme.CUNNINGHAM && (
           <img
             className="pattern"
             src={
-            theme === Theme.DARK ? "pattern_dark.png" : "pattern_default.png"
+              variant === Variant.DARK
+                ? "pattern_dark.png"
+                : "pattern_default.png"
             }
             alt="Background pattern"
           />
+        )}
         {page === Page.HOME && <Home changePage={(p) => setPage(p)} />}
         {page === Page.CREATE && <Create changePage={(p) => setPage(p)} />}
       </div>
 
       <div className="theme-switch">
+        <Select
+          value={theme}
+          label="Theme"
+          clearable={false}
+          options={Object.keys(THEMES).map((key) => ({
+            value: key,
+            label: key[0].toUpperCase() + key.slice(1),
+          }))}
+          onChange={(e) => {
+            setTheme(e.target.value as Theme);
+            if (THEMES[e.target.value as Theme][variant] === undefined) {
+              setVariant(
+                variant === Variant.LIGHT ? Variant.DARK : Variant.LIGHT,
+              );
+            }
+          }}
+        />
         <Button
           color="tertiary"
           icon={
             <span className="material-icons">
-              {theme === Theme.DARK ? "light_mode" : "dark_mode"}
+              {variant === Variant.DARK ? "light_mode" : "dark_mode"}
             </span>
           }
           onClick={() => {
-            setTheme(theme === Theme.DARK ? Theme.DEFAULT : Theme.DARK);
+            setVariant(
+              variant === Variant.LIGHT ? Variant.DARK : Variant.LIGHT,
+            );
           }}
+          disabled={
+            THEMES[theme][
+              variant === Variant.LIGHT ? Variant.DARK : Variant.LIGHT
+            ] === undefined
+          }
         />
       </div>
     </CunninghamProvider>

apps/demo/src/index.scss

@@ -35,6 +35,12 @@ html {
   position: fixed;
   right: 1rem;
   top: 0.75rem;
+
+  display: flex;
+  align-items: center;
+  gap: 1rem;
+
+  --c--components--forms-field--width: 150px;
 }
 
 .card {