[ADF-2077] [Destination picker] User should not be able to copy / mo… (#2978)

* [ADF-20177] [Destination picker] User should not be able to copy / move items into a site outside of the documentLibrary

* [ADF-20177] added unit tests for the change

* [ADF-2077] refactor code and unit tests after code review

* [ADF-2077] more refactoring to make the unit tests messages more clear

lib/content-services/content-node-selector/content-node-dialog.service.ts

@@ -88,7 +88,7 @@ export class ContentNodeDialogService {
                 currentFolderId: contentEntry.parentId,
                 imageResolver: this.imageResolver.bind(this),
                 rowFilter : this.rowFilter.bind(this, contentEntry.id),
-                isSelectionValid: this.hasEntityCreatePermission.bind(this),
+                isSelectionValid: this.isCopyMoveSelectionValid.bind(this),
                 select: select
             };
 
@@ -188,10 +188,18 @@ export class ContentNodeDialogService {
         return entry.isFolder;
     }
 
+    private isCopyMoveSelectionValid(entry: MinimalNodeEntryEntity): boolean {
+        return this.hasEntityCreatePermission(entry) && !this.isSite(entry);
+    }
+
     private hasEntityCreatePermission(entry: MinimalNodeEntryEntity): boolean {
         return this.contentService.hasPermission(entry, 'create');
     }
 
+    private isSite(entry) {
+        return !!entry.guid || entry.nodeType === 'st:site' || entry.nodeType === 'st:sites';
+    }
+
     /** Closes the currently open dialog. */
     close() {
         this.dialog.closeAll();