extract AlertMessage to its own file

core/static/bundled/utils/alert-message.ts

@@ -0,0 +1,38 @@
+interface AlertParams {
+  success?: boolean;
+  duration?: number;
+}
+
+export class AlertMessage {
+  public open: boolean;
+  public success: boolean;
+  public content: string;
+  private timeoutId?: number;
+  private readonly defaultDuration: number;
+
+  constructor(params?: { defaultDuration: number }) {
+    this.open = false;
+    this.content = "";
+    this.timeoutId = null;
+    this.defaultDuration = params?.defaultDuration ?? 2000;
+  }
+
+  public display(message: string, params: AlertParams) {
+    this.clear();
+    this.open = true;
+    this.content = message;
+    this.success = params.success ?? true;
+    this.timeoutId = setTimeout(() => {
+      this.open = false;
+      this.timeoutId = null;
+    }, params.duration ?? this.defaultDuration);
+  }
+
+  public clear() {
+    if (this.timeoutId !== null) {
+      clearTimeout(this.timeoutId);
+      this.timeoutId = null;
+    }
+    this.open = false;
+  }
+}