Implement date validators

Elwig/Helpers/Validator.cs

@@ -345,13 +345,70 @@ namespace Elwig.Helpers {
         }
 
         public static ValidationResult CheckDate(TextBox input, bool required) {
-            // TODO
+            return CheckDate(input, required, false);
-            return new(true, "Not implemented yet");
         }
 
         public static ValidationResult CheckPartialDate(TextBox input, bool required) {
-            // TODO
+            return CheckDate(input, required, true);
-            return new(true, "Not implemented yet");
+        }
+
+        private static ValidationResult CheckDate(TextBox input, bool required, bool partial) {
+            string text = "";
+            int pos = input.CaretIndex;
+            int p = 0;
+            var parts = new string?[3];
+            parts[0] = "";
+            for (int i = 0; i < input.Text.Length; i++) {
+                char ch = input.Text[i];
+                if (ch == '.') {
+                    if (p < 2 && (parts[p]?.Length > 0 || pos == text.Length)) {
+                        if (parts[p]?.Length == 1 && ((pos != text.Length && pos != text.Length - 1) || !input.IsFocused)) {
+                            parts[p] = "0" + parts[p];
+                            text = text[..(text.Length - 1)] + "0" + text[^1];
+                        }
+                        parts[++p] = "";
+                        text += '.';
+                    }
+                } else if (char.IsAsciiDigit(ch)) {
+                    if ((partial && parts[p]?.Length < 4) || (!partial && ((p < 2 && parts[p]?.Length < 2) || (p == 2 && parts[2]?.Length < 4)))) {
+                        parts[p] += ch;
+                        text += ch;
+                    }
+                    if (p == 0 && pos == 1 && input.Text.Length >= 4 && input.Text.Length <= 9) {
+                        parts[++p] = "";
+                        text += '.';
+                        continue;  // skip caret update
+                    }
+                }
+
+                if (i == input.CaretIndex - 1) {
+                    pos = text.Length;
+                }
+            }
+
+            input.Text = text;
+            input.CaretIndex = pos;
+
+            if (text.Length == 0)
+                return required ? new(false, "Datum ist nicht optional") : new(true, null);
+
+            if (partial) {
+                if (p == 0) {
+                    // only year provided
+                    return (parts[0]?.Length == 4) ? new(true, null) : new(false, "Datum ist ungültig");
+                } else if (p == 1) {
+                    // only month and year provided
+                    int m = parts[0] != null && parts[0] != "" ? int.Parse(parts[0] ?? "0") : 0;
+                    if (parts[1]?.Length != 4 || parts[0]?.Length != 2 || m < 1 || m > 12)
+                        return new(false, "Datum ist ungültig");
+                    return new(true, null);
+                }
+            }
+
+            if (!DateOnly.TryParseExact(text, "dd.MM.yyyy", out _))
+                return new(false, "Datum ist ungültig");
+
+            return new(true, null);
         }
 
         public static ValidationResult CheckVNr(TextBox input, bool required, AppDbContext ctx, Contract? c) {

Elwig/Windows/AdministrationWindow.cs

@@ -258,10 +258,18 @@ namespace Elwig.Windows {
             InputTextChanged((TextBox)sender, Validator.CheckPartialDate);
         }
 
+        protected void PartialDateInput_LostFocus(object sender, RoutedEventArgs evt) {
+            InputLostFocus((TextBox)sender, Validator.CheckPartialDate);
+        }
+
         protected void DateInput_TextChanged(object sender, RoutedEventArgs evt) {
             InputTextChanged((TextBox)sender, Validator.CheckDate);
         }
 
+        protected void DateInput_LostFocus(object sender, RoutedEventArgs evt) {
+            InputLostFocus((TextBox)sender, Validator.CheckDate);
+        }
+
         protected void PlzInput_TextChanged(object sender, RoutedEventArgs evt) {
             var plz = (TextBox)sender;
             InputTextChanged(plz, Validator.CheckPlz);

Elwig/Windows/MainWindow.xaml.cs

@@ -1,11 +1,5 @@
-using Microsoft.EntityFrameworkCore;
-using System;
-using System.Collections.Generic;
 using System.ComponentModel;
 using System.Linq;
-using System.Runtime.Intrinsics.X86;
-using System.Text;
-using System.Threading.Tasks;
 using System.Windows;
 using Elwig.Documents;
 using Elwig.Helpers;

Elwig/Windows/MemberAdminWindow.xaml

@@ -140,7 +140,7 @@
 
                 <Label Content="Geburtstag:" Margin="10,100,0,0" Grid.Column="0"/>
                 <TextBox x:Name="BirthdayInput" Margin="0,100,0,0" Grid.Column="1" Width="78" TextAlignment="Right" HorizontalAlignment="Left"
-                         TextChanged="PartialDateInput_TextChanged"/>
+                         TextChanged="PartialDateInput_TextChanged" LostFocus="PartialDateInput_LostFocus"/>
 
                 <Label Content="Adresse:" Margin="10,130,0,0"/>
                 <TextBox x:Name="AddressInput" Margin="0,130,10,0" Grid.Column="1" Grid.ColumnSpan="3"
@@ -248,11 +248,11 @@
 
                 <Label Content="Eintritt:" Margin="10,10,0,0" Grid.Column="0"/>
                 <TextBox x:Name="EntryDateInput" Margin="0,10,10,0" Width="78" Grid.Column="1" HorizontalAlignment="Left" TextAlignment="Right"
-                         TextChanged="DateInput_TextChanged"/>
+                         TextChanged="DateInput_TextChanged" LostFocus="DateInput_LostFocus"/>
 
                 <Label Content="Austritt:" Margin="10,40,0,0" Grid.Column="0"/>
                 <TextBox x:Name="ExitDateInput" Margin="0,40,10,0" Width="78" Grid.Column="1" HorizontalAlignment="Left" TextAlignment="Right"
-                         TextChanged="DateInput_TextChanged"/>
+                         TextChanged="DateInput_TextChanged" LostFocus="DateInput_LostFocus"/>
 
                 <Label Content="Geschäftsanteile:" Margin="10,70,0,0" Grid.Column="0"/>
                 <TextBox x:Name="BusinessSharesInput" Margin="0,70,10,0" Width="48" Grid.Column="1" HorizontalAlignment="Left" TextAlignment="Right"