add asset utils (php side)

lib/Util/AssetUtil.php

@@ -0,0 +1,64 @@
+<?php
+
+namespace OCA\SideMenu\Util;
+
+use OC_Util;
+use OCA\SideMenu\AppInfo\Application;
+
+/**
+ * class AssetUtil.
+ *
+ * @author Simon Vieille <simon@deblan.fr>
+ */
+class AssetUtil
+{
+    protected array $entrypoints;
+    protected static ?AssetUtil $instance = null;
+
+    public function __construct()
+    {
+        $this->entrypoints = json_decode(
+            file_get_contents(__DIR__.'/../../assets/entrypoints.json'),
+            true
+        )['entrypoints'];
+    }
+
+    public static function getInstance(): self
+    {
+        if (null === self::$instance) {
+            self::$instance = new self();
+        }
+
+        return self::$instance;
+    }
+
+    public function addEntrypointAsset($entry, $type, $key): self
+    {
+        $file = basename($this->entrypoints[$entry][$type][$key]);
+        $path = $this->generatePath('assets', $file);
+
+        return $this->addAsset($type, $path);
+    }
+
+    public function addAsset($type, $path): self
+    {
+        $path = preg_replace('/\.(css|js)$/', '', $path);
+
+        if ('css' === $type) {
+            OC_Util::$styles[] = $path;
+        } elseif ('js' === $type) {
+            OC_Util::$scripts[] = $path;
+        }
+
+        return $this;
+    }
+
+    public function generatePath($directory, $file): string
+    {
+        return implode('/', [
+            Application::APP_ID,
+            $directory,
+            $file,
+        ]);
+    }
+}