Seperation of concerns: Seperated used File Management form Overall FIle Management

HaWeb/Models/FileList.cs

@@ -0,0 +1,25 @@
+namespace HaWeb.Models;
+using HaWeb.XMLParser;
+using System.Text.Json.Serialization;
+
+public class FileList {
+    private HashSet<XMLRootDocument>? _Files;
+
+    [JsonIgnore]
+    public IXMLRoot XMLRoot { get; private set; }
+
+    public FileList(IXMLRoot xmlRoot) {
+        XMLRoot = xmlRoot;
+    }
+
+    public void Add(XMLRootDocument document) {
+        if (document.Prefix != XMLRoot.Prefix)
+            throw new Exception("Diese Liste kann nur Elemente des Typs " + XMLRoot.Prefix + " enthalten");
+
+        if (_Files == null) _Files = new HashSet<XMLRootDocument>();
+        if (!_Files.Contains(document)) _Files.Add(document);
+    }
+
+    public List<XMLRootDocument>? GetFileList()
+        => this._Files != null ? this._Files.ToList() : null;
+}