AppDbContext: Add NextAvNr()

Elwig/App.xaml.cs

@@ -17,6 +17,7 @@ using Elwig.Windows;
 using Elwig.Dialogs;
 using System.Threading.Tasks;
 using Elwig.Helpers.Billing;
+using Elwig.Models.Entities;
 
 namespace Elwig {
     public partial class App : Application {
@@ -221,6 +222,13 @@ namespace Elwig {
             return w;
         }
 
+        public static BaseDataWindow FocusBaseDataSeason(int year) {
+            var w = FocusBaseData();
+            w.Seasons.Focus();
+            ControlUtils.SelectListBoxItem(w.SeasonList, s => (s as Season)?.Year, year);
+            return w;
+        }
+
         public static SeasonFinishWindow FocusSeasonFinish() {
             return FocusWindow<SeasonFinishWindow>(() => new());
         }

Elwig/Helpers/AppDbContext.cs

@@ -200,6 +200,13 @@ namespace Elwig.Helpers {
             return c + 1;
         }
 
+        public async Task<int> NextAvNr(int year) {
+            int c = 0;
+            (await PaymentVariants.Where(v => v.Year == year).Select(v => v.AvNr).ToListAsync())
+                .ForEach(a => { if (a <= c + 100) c = a; });
+            return c + 1;
+        }
+
         public async Task<WineQualLevel> GetWineQualityLevel(double kmw) {
             return await WineQualityLevels
                 .Where(q => !q.IsPredicate && (q.MinKmw == null || q.MinKmw <= kmw))

Elwig/Windows/BaseDataWindow.xaml

@@ -375,7 +375,7 @@
                 </Grid>
             </TabItem>
 
-            <TabItem Header="Saisons">
+            <TabItem Header="Saisons" x:Name="Seasons">
                 <Grid>
                     <Grid.ColumnDefinitions>
                         <ColumnDefinition Width="180"/>