Implemented Tailwind CSS class list extraction and integrated it into the build process of the frontend package

Hosts/Moonlight.Frontend.Host/Styles/extract-classes.mjs

@@ -0,0 +1,25 @@
+import fs from 'fs';
+import selectorParser from 'postcss-selector-parser';
+
+export default function extractTailwindClasses(opts = {}) {
+    const classSet = new Set();
+
+    return {
+        postcssPlugin: 'extract-tailwind-classes',
+        Rule(rule) {
+            selectorParser(selectors => {
+                selectors.walkClasses(node => {
+                    classSet.add(node.value);
+                });
+            }).processSync(rule.selector);
+        },
+        OnceExit() {
+            const classArray = Array.from(classSet).sort();
+            fs.mkdirSync('../../../Moonlight.Frontend/Styles', { recursive: true });
+            fs.writeFileSync('../../../Moonlight.Frontend/Styles/Moonlight.Frontend.map', classArray.join('\n'));
+            console.log(`Extracted classes ${classArray.length}`);
+        }
+    };
+}
+
+extractTailwindClasses.postcss = true;

Hosts/Moonlight.Frontend.Host/Styles/package.json

@@ -1,15 +1,20 @@
 {
   "scripts": {
-    "tailwind": "npx postcss styles.css -o ../wwwroot/style.min.css --watch",
-    "tailwind-build": "npx postcss styles.css -o ../wwwroot/style.min.css"
+    "dev": "npx postcss styles.css -o ../wwwroot/style.min.css --watch",
+    "dev-build": "npx postcss styles.css -o ../wwwroot/style.min.css",
+    "build": "cross-env EXTRACT_CLASSES=true npx postcss styles.css -o ../wwwroot/style.min.css"
   },
   "dependencies": {
     "@tailwindcss/postcss": "^4.1.18",
     "cssnano": "^7.1.2",
     "postcss": "^8.5.6",
     "postcss-cli": "^11.0.1",
+    "postcss-selector-parser": "^7.1.1",
     "shadcnblazor": "^1.0.5",
     "tailwindcss": "^4.1.18",
     "tw-animate-css": "^1.4.0"
+  },
+  "devDependencies": {
+    "cross-env": "^10.1.0"
   }
 }

Hosts/Moonlight.Frontend.Host/Styles/postcss.config.mjs

@@ -1,8 +1,18 @@
-export default {
-    plugins: {
-        "@tailwindcss/postcss": {},
-        "cssnano":{
-            preset: 'default'
-        }
-    }
-}
+import tailwindcss from '@tailwindcss/postcss';
+import cssnano from 'cssnano';
+import extractTailwindClasses from './extract-classes.mjs';
+
+const plugins = [
+    tailwindcss,
+    cssnano({
+        preset: 'default'
+    })
+];
+
+if (process.env.EXTRACT_CLASSES === "true") {
+    plugins.push(extractTailwindClasses());
+}
+
+export default {
+    plugins
+};