[chore:] combine split into four possible variants of merging

MainWindow.axaml

@@ -3,6 +3,7 @@
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
         mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
+        MinWidth="1000" MinHeight="600"
         x:Class="Logof_Client.MainWindow" WindowState="Maximized" Icon="assets/icon.ico"
         Title="Logof Client">
     <Border>
@@ -145,9 +146,53 @@
                                 </Button>
                             </StackPanel>
                         </Grid>
-                        <Grid Grid.Row="2" Margin="20">
+                        <Grid Grid.Row="2" Margin="20" IsVisible="True" x:Name="GrdCalcMan">
                             <Image Source="assets/calc_man.png" VerticalAlignment="Center" HorizontalAlignment="Center" />
                         </Grid>
+                        <Grid Grid.Row="2" Margin="20" IsVisible="False" x:Name="GrdCombineTypes">
+                            <StackPanel Orientation="Horizontal" HorizontalAlignment="Center" Spacing="10"
+                                        Margin="5,0,0,0">
+                                <Button HorizontalAlignment="Stretch" MinWidth="240"
+                                        HorizontalContentAlignment="Center" x:Name="BtnCombineUnion"
+                                        Margin="0,0,0,10">
+                                    <StackPanel Orientation="Horizontal">
+                                        <LucideIcon Kind="SquaresUnite" Width="36" Height="36" />
+                                        <Label Content="Vereinigung" VerticalContentAlignment="Center" FontSize="15"
+                                               FontWeight="Bold" />
+                                    </StackPanel>
+                                </Button>
+                                <Button HorizontalAlignment="Stretch" MinWidth="240"
+                                        HorizontalContentAlignment="Center" x:Name="BtnCombineIntersect"
+                                        Margin="0,0,0,10">
+                                    <StackPanel Orientation="Horizontal">
+                                        <LucideIcon Kind="SquaresIntersect" Width="36" Height="36" />
+                                        <Label Content="Schnittmenge" VerticalContentAlignment="Center"
+                                               FontSize="15"
+                                               FontWeight="Bold" />
+                                    </StackPanel>
+                                </Button>
+                                <Button HorizontalAlignment="Stretch" MinWidth="240"
+                                        HorizontalContentAlignment="Center" x:Name="BtnCombineDifference"
+                                        Margin="0,0,0,10">
+                                    <StackPanel Orientation="Horizontal">
+                                        <LucideIcon Kind="SquaresSubtract" Width="36" Height="36" />
+                                        <Label Content="Differenz" VerticalContentAlignment="Center"
+                                               FontSize="15"
+                                               FontWeight="Bold" />
+                                    </StackPanel>
+                                </Button>
+                                <Button HorizontalAlignment="Stretch" MinWidth="240"
+                                        HorizontalContentAlignment="Center" x:Name="BtnCombineSymmetric"
+                                        Margin="0,0,0,10">
+                                    <StackPanel Orientation="Horizontal">
+                                        <LucideIcon Kind="SquaresExclude" Width="36" Height="36" />
+                                        <Label Content="Symmetrische Differenz" VerticalContentAlignment="Center"
+                                               FontSize="15"
+                                               FontWeight="Bold" />
+                                    </StackPanel>
+                                </Button>
+                            </StackPanel>
+                        </Grid>
                     </Grid>
                 </TabItem>
                 <TabItem IsEnabled="False">

MainWindow.axaml.cs

@@ -108,6 +108,7 @@ public partial class MainWindow : Window
 
     private void BtnCheck_OnClick(object? sender, RoutedEventArgs e)
     {
+        MakeCalcManVisible();
         if (LstCustomerAdressSets.SelectedIndex == -1)
         {
             MessageBox.Show(null, "Bitte zunächst ein Adress-Set auswählen", "Kein Adress-Set ausgewählt");
@@ -135,17 +136,19 @@ public partial class MainWindow : Window
 
     private void BtnCombine_OnClick(object? sender, RoutedEventArgs e)
     {
-        if (filePath == null)
+        GrdCalcMan.IsVisible = false;
-        {
+        GrdCombineTypes.IsVisible = true;
-            MessageBox.Show(null, "Bitte zunächst eine Datei auswählen", "Datei fehlt");
+    }
-            return;
-        }
 
-        StartCombine(filePath);
+    private void MakeCalcManVisible()
+    {
+        GrdCalcMan.IsVisible = true;
+        GrdCombineTypes.IsVisible = false;
     }
 
     private async void StartCombine(Uri path)
     {
+        MakeCalcManVisible();
         var addresses = DataImport.ImportKasAddressList(path);
         var progressWindow = new ProgressWindow();
         var address_list = new List<KasAddressList> { addresses.Item2 };
@@ -294,6 +297,7 @@ public partial class MainWindow : Window
 
     private void LstCustomers_OnSelectionChanged(object? sender, SelectionChangedEventArgs e)
     {
+        MakeCalcManVisible();
         if (LstCustomers.SelectedItems == null || LstCustomers.SelectedIndex == -1) return;
         var customer_id = int.Parse(LstCustomers.SelectedItem.ToString().Split(" - ")[0]);
         RefreshAddressSetListItems(customer_id);
@@ -301,6 +305,7 @@ public partial class MainWindow : Window
 
     private async void BtnCustomerAddressSetImport_OnClick(object? sender, RoutedEventArgs e)
     {
+        MakeCalcManVisible();
         var opts = new FilePickerOpenOptions();
         opts.Title = "Address-Set importieren...";
         opts.AllowMultiple = false;
@@ -361,7 +366,14 @@ public partial class MainWindow : Window
 
     public void RefreshAddressSetListItems(int customer_id)
     {
+        BtnCheck.IsEnabled = false;
+        BtnCombine.IsEnabled = false;
+        BtnGenerateLabels.IsEnabled = false;
+        BtnRepair.IsEnabled = false;
+        BtnShorten.IsEnabled = false;
+
         if (LstCustomers.SelectedIndex < 0) return;
+
         LstCustomerAdressSets.SelectedItems = null;
         LstCustomerAdressSets.Items.Clear();
         foreach (var k in Settings._instance.addressSets.addresses)
@@ -372,11 +384,11 @@ public partial class MainWindow : Window
 
     private void LstCustomerAdressSets_OnSelectionChanged(object? sender, SelectionChangedEventArgs e)
     {
+        MakeCalcManVisible();
         if (LstCustomerAdressSets.SelectedItems == null || LstCustomerAdressSets.SelectedIndex == -1)
         {
             BtnCheck.IsEnabled = false;
             BtnCombine.IsEnabled = false;
-
             BtnGenerateLabels.IsEnabled = false;
             BtnRepair.IsEnabled = false;
             BtnShorten.IsEnabled = false;