Implemented cost entries excluding cost entry details.

ucalc/Constants.cs

@@ -16,5 +16,8 @@ namespace UCalc
 
         public static readonly ImmutableList<string> SalutationStrs =
             ((Salutation[]) Enum.GetValues(typeof(Salutation))).Select(value => value.AsString()).ToImmutableList();
+
+        public static readonly ImmutableList<string> CostDivisionStrs =
+            ((CostDivision[]) Enum.GetValues(typeof(CostDivision))).Select(value => value.AsString()).ToImmutableList();
     }
 }

ucalc/Controls/Converters.cs

@@ -79,6 +79,21 @@ namespace UCalc.Controls
         }
     }
 
+    public class FlatToAffectedConverter : IValueConverter
+    {
+        public CostProperty Cost { get; set; }
+
+        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
+        {
+            return Cost.AffectedFlats.Contains((FlatProperty) value);
+        }
+
+        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
+        {
+            throw new InvalidOperationException();
+        }
+    }
+
     public class EmptyMultiPropertyToVisibilityConverter : IValueConverter
     {
         public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
@@ -133,4 +148,17 @@ namespace UCalc.Controls
             throw new InvalidOperationException();
         }
     }
+
+    public class NegateConverter : IValueConverter
+    {
+        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
+        {
+            return !(bool?) value;
+        }
+
+        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
+        {
+            return !(bool?) value;
+        }
+    }
 }

ucalc/CostWindow.xaml

@@ -15,6 +15,13 @@
         ShowInTaskbar="False"
         Icon="logo.ico">
 
+    <Window.Resources>
+        <controls:NegateConverter x:Key="NegateConverter" />
+        <controls:FlatToAffectedConverter x:Key="FlatToAffectedConverter" />
+        <controls:DatePickerTextToDateTimeConverter x:Key="DatePickerTextToDateTimeConverter" />
+        <controls:EmptyMultiPropertyToVisibilityConverter x:Key="EmptyMultiPropertyToVisibilityConverter" />
+    </Window.Resources>
+
     <DockPanel>
         <StackPanel DockPanel.Dock="Bottom">
             <Separator Margin="0, 12, 0, 0"
@@ -52,6 +59,203 @@
                         Text="{Binding Path=Cost.Name.Value, RelativeSource={RelativeSource AncestorType=local:CostWindow}, UpdateSourceTrigger=PropertyChanged}" />
                 </DockPanel>
 
+                <DockPanel Margin="12, 8, 12, 0">
+                    <TextBlock DockPanel.Dock="Left"
+                               Margin="4, 0, 4, 0"
+                               Text="Detailiert in Ausdruck berechnen:"
+                               Width="172"
+                               TextWrapping="Wrap"
+                               Foreground="{x:Static local:Constants.SubMainColor}" />
+
+                    <CheckBox
+                        IsChecked="{Binding Path=Cost.DisplayInBill.Value, RelativeSource={RelativeSource AncestorType=local:CostWindow}, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}" />
+
+                </DockPanel>
+
+                <controls:SectionHeader Header="Verteilung" />
+
+                <DockPanel Margin="12, 0, 12, 0">
+                    <Label DockPanel.Dock="Left"
+                           Content="Betrifft alle Wohnungen:"
+                           Width="180"
+                           Foreground="{x:Static local:Constants.SubMainColor}" />
+
+                    <CheckBox
+                        VerticalAlignment="Center"
+                        IsChecked="{Binding Path=Cost.AffectsAll.Value, RelativeSource={RelativeSource AncestorType=local:CostWindow}, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}" />
+
+                </DockPanel>
+
+                <DockPanel Margin="12, 8, 12, 0">
+                    <Label DockPanel.Dock="Left"
+                           Content="Betroffene Wohnungen:"
+                           Width="180"
+                           Foreground="{x:Static local:Constants.SubMainColor}" />
+
+                    <controls:ErrorIcon Margin="12, 0, 0, 0"
+                                        DockPanel.Dock="Right"
+                                        VerticalAlignment="Center"
+                                        Property="{Binding Path=Cost.AffectedFlats, RelativeSource={RelativeSource AncestorType=local:CostWindow}}" />
+
+                    <ListBox Height="120"
+                             ItemsSource="{Binding Path=House.Flats, RelativeSource={RelativeSource AncestorType=local:CostWindow}}"
+                             IsEnabled="{Binding Path=Cost.AffectsAll.Value, RelativeSource={RelativeSource AncestorType=local:CostWindow}, Converter={StaticResource NegateConverter}}">
+                        <ListBox.ItemTemplate>
+                            <DataTemplate>
+                                <CheckBox Content="{Binding Name.Value}"
+                                          IsChecked="{Binding Path=., Converter={StaticResource FlatToAffectedConverter}, Mode=OneWay, UpdateSourceTrigger=PropertyChanged}"
+                                          Checked="OnFlatChecked"
+                                          Unchecked="OnFlatUnchecked" />
+                            </DataTemplate>
+                        </ListBox.ItemTemplate>
+                    </ListBox>
+                </DockPanel>
+
+                <DockPanel Margin="12, 12, 12, 0">
+                    <TextBlock DockPanel.Dock="Left"
+                               Margin="4, 0, 4, 0"
+                               Text="Lege Kosten für unvermietete Wohnungen auf vermietete Wohnungen um:"
+                               Width="172"
+                               TextWrapping="Wrap"
+                               Foreground="{x:Static local:Constants.SubMainColor}" />
+
+                    <CheckBox
+                        IsChecked="{Binding Path=Cost.IncludeUnrented.Value, RelativeSource={RelativeSource AncestorType=local:CostWindow}, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}" />
+
+                </DockPanel>
+
+                <DockPanel Margin="12, 8, 12, 8">
+                    <Label DockPanel.Dock="Left"
+                           Content="Art der Aufteilung:"
+                           Width="180"
+                           Foreground="{x:Static local:Constants.SubMainColor}" />
+
+                    <ComboBox Margin="0, 0, 28, 0"
+                              ItemsSource="{x:Static local:Constants.CostDivisionStrs}"
+                              SelectedIndex="{Binding Path=Cost.Division.Value, RelativeSource={RelativeSource AncestorType=local:CostWindow}}" />
+                </DockPanel>
+
+                <controls:SectionHeader Header="Zeiträume" />
+
+                <DockPanel>
+                    <controls:ErrorIcon Margin="0, 0, 12, 0"
+                                        DockPanel.Dock="Right"
+                                        VerticalAlignment="Center"
+                                        Property="{Binding Path=Cost.Entries, RelativeSource={RelativeSource AncestorType=local:CostWindow}}"
+                                        Visibility="{Binding Path=Cost.Entries.Count, RelativeSource={RelativeSource AncestorType=local:CostWindow}, Converter={StaticResource EmptyMultiPropertyToVisibilityConverter}}" />
+
+                    <controls:HighlightButton Margin="12, 0, 12, 0"
+                                              HighlightForeground="{x:Static local:Constants.SubMainColor}"
+                                              HighlightBackground="{x:Static local:Constants.MainColor}"
+                                              Click="OnAddCostEntryClick">
+                        <Viewbox Width="24"
+                                 Height="24"
+                                 Margin="12, 12, 6, 12"
+                                 Stretch="Uniform">
+                            <Canvas Width="512" Height="512">
+                                <Canvas.RenderTransform>
+                                    <TranslateTransform X="0" Y="0" />
+                                </Canvas.RenderTransform>
+                                <Path>
+                                    <Path.Data>
+                                        <PathGeometry
+                                            Figures="M256 8C119 8 8 119 8 256s111 248 248 248 248-111 248-248S393 8 256 8zm144 276c0 6.6-5.4 12-12 12h-92v92c0 6.6-5.4 12-12 12h-56c-6.6 0-12-5.4-12-12v-92h-92c-6.6 0-12-5.4-12-12v-56c0-6.6 5.4-12 12-12h92v-92c0-6.6 5.4-12 12-12h56c6.6 0 12 5.4 12 12v92h92c6.6 0 12 5.4 12 12v56z"
+                                            FillRule="NonZero" />
+                                    </Path.Data>
+                                </Path>
+                            </Canvas>
+                        </Viewbox>
+
+                        <Label Content="Zeitraum hinzufügen"
+                               Margin="0, 12, 12, 12" />
+                    </controls:HighlightButton>
+                </DockPanel>
+
+                <ItemsControl
+                    ItemsSource="{Binding Path=Cost.Entries, RelativeSource={RelativeSource AncestorType=local:CostWindow}}"
+                    Margin="12, 0, 12, 12">
+                    <ItemsControl.ItemTemplate>
+                        <DataTemplate>
+                            <DockPanel>
+                                <controls:HighlightButton DockPanel.Dock="Right"
+                                                          HighlightForeground="Red"
+                                                          HighlightBackground="White"
+                                                          Click="OnCostEntryDeleteClick">
+                                    <Viewbox Width="24"
+                                             Height="24"
+                                             Margin="8, 12, 8, 12"
+                                             Stretch="Uniform">
+                                        <Canvas Width="448" Height="512">
+                                            <Canvas.RenderTransform>
+                                                <TranslateTransform X="0" Y="0" />
+                                            </Canvas.RenderTransform>
+                                            <Path>
+                                                <Path.Data>
+                                                    <PathGeometry
+                                                        Figures="M32 464a48 48 0 0 0 48 48h288a48 48 0 0 0 48-48V128H32zm272-256a16 16 0 0 1 32 0v224a16 16 0 0 1-32 0zm-96 0a16 16 0 0 1 32 0v224a16 16 0 0 1-32 0zm-96 0a16 16 0 0 1 32 0v224a16 16 0 0 1-32 0zM432 32H312l-9.4-18.7A24 24 0 0 0 281.1 0H166.8a23.72 23.72 0 0 0-21.4 13.3L136 32H16A16 16 0 0 0 0 48v32a16 16 0 0 0 16 16h416a16 16 0 0 0 16-16V48a16 16 0 0 0-16-16z"
+                                                        FillRule="NonZero" />
+                                                </Path.Data>
+                                            </Path>
+                                        </Canvas>
+                                    </Viewbox>
+                                </controls:HighlightButton>
+
+                                <StackPanel Margin="0, 8, 8, 8">
+                                    <DockPanel Margin="0, 0, 0, 2">
+                                        <Label DockPanel.Dock="Left" Content="Startdatum:"
+                                               Width="180"
+                                               Foreground="{x:Static local:Constants.SubMainColor}" />
+
+                                        <controls:ErrorIcon Margin="12, 0, 0, 0"
+                                                            DockPanel.Dock="Right"
+                                                            VerticalAlignment="Center"
+                                                            Property="{Binding StartDate}" />
+
+                                        <DatePicker VerticalAlignment="Center"
+                                                    MinHeight="22"
+                                                    DisplayDateStart="{Binding Path=Model.StartDate, RelativeSource={RelativeSource AncestorType=local:CostWindow}, Mode=OneWay}"
+                                                    DisplayDateEnd="{Binding Path=Model.EndDate, RelativeSource={RelativeSource AncestorType=local:CostWindow}, Mode=OneWay}"
+                                                    Text="{Binding Path=StartDate.Value, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay, Converter={StaticResource DatePickerTextToDateTimeConverter}}" />
+
+                                    </DockPanel>
+
+                                    <DockPanel Margin="0, 2, 0, 2">
+                                        <Label DockPanel.Dock="Left" Content="Enddatum:"
+                                               Width="180"
+                                               Foreground="{x:Static local:Constants.SubMainColor}" />
+
+                                        <controls:ErrorIcon Margin="12, 0, 0, 0"
+                                                            DockPanel.Dock="Right"
+                                                            VerticalAlignment="Center"
+                                                            Property="{Binding EndDate}" />
+
+                                        <DatePicker VerticalAlignment="Center"
+                                                    MinHeight="22"
+                                                    DisplayDateStart="{Binding Path=Model.StartDate, RelativeSource={RelativeSource AncestorType=local:CostWindow}, Mode=OneWay}"
+                                                    DisplayDateEnd="{Binding Path=Model.EndDate, RelativeSource={RelativeSource AncestorType=local:CostWindow}, Mode=OneWay}"
+                                                    Text="{Binding Path=EndDate.Value, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay, Converter={StaticResource DatePickerTextToDateTimeConverter}}" />
+
+                                    </DockPanel>
+
+                                    <DockPanel Margin="0, 2, 0, 0">
+                                        <Label DockPanel.Dock="Left" Content="Betrag:"
+                                               Width="180"
+                                               Foreground="{x:Static local:Constants.SubMainColor}" />
+
+                                        <controls:ErrorIcon Margin="12, 0, 0, 0"
+                                                            DockPanel.Dock="Right"
+                                                            VerticalAlignment="Center"
+                                                            Property="{Binding Amount}" />
+
+                                        <TextBox VerticalAlignment="Center"
+                                                 MinHeight="22"
+                                                 Text="{Binding Path=Amount.Value, UpdateSourceTrigger=PropertyChanged}" />
+                                    </DockPanel>
+                                </StackPanel>
+                            </DockPanel>
+                        </DataTemplate>
+                    </ItemsControl.ItemTemplate>
+                </ItemsControl>
 
             </StackPanel>
         </ScrollViewer>

ucalc/CostWindow.xaml.cs

@@ -1,4 +1,6 @@
 using System.Windows;
+using System.Windows.Controls;
+using UCalc.Controls;
 using UCalc.Models;
 
 namespace UCalc
@@ -14,13 +16,40 @@ namespace UCalc
             Model = model;
             Cost = cost;
             House = house;
-
             InitializeComponent();
+
+            ((FlatToAffectedConverter) FindResource("FlatToAffectedConverter")).Cost = Cost;
         }
 
         private void OnOkClick(object sender, RoutedEventArgs e)
         {
             Close();
         }
+
+        private void OnFlatChecked(object sender, RoutedEventArgs e)
+        {
+            var flat = (FlatProperty) ((CheckBox) sender).DataContext;
+
+            Cost.AffectedFlats.Add(flat);
+        }
+
+        private void OnFlatUnchecked(object sender, RoutedEventArgs e)
+        {
+            var flat = (FlatProperty) ((CheckBox) sender).DataContext;
+
+            Cost.AffectedFlats.Remove(flat);
+        }
+
+        private void OnCostEntryDeleteClick(object sender, RoutedEventArgs e)
+        {
+            var entry = (CostEntryProperty) ((HighlightButton) sender).DataContext;
+
+            Cost.Entries.Remove(entry);
+        }
+
+        private void OnAddCostEntryClick(object sender, RoutedEventArgs e)
+        {
+            Cost.Entries.Add();
+        }
     }
 }

ucalc/Data/Billing.cs

@@ -296,7 +296,7 @@ namespace UCalc.Data
 
     public class CostEntryDetails
     {
-        public decimal TotalPrice { get; set; }
+        public decimal TotalAmount { get; set; }
         public decimal UnitCount { get; set; }
         public List<decimal> DiscountsInUnits { get; private set; }
 
@@ -307,7 +307,7 @@ namespace UCalc.Data
 
         private bool Equals(CostEntryDetails other)
         {
-            return TotalPrice == other.TotalPrice && UnitCount == other.UnitCount &&
+            return TotalAmount == other.TotalAmount && UnitCount == other.UnitCount &&
                    DiscountsInUnits.SequenceEqual(other.DiscountsInUnits);
         }
 
@@ -322,7 +322,7 @@ namespace UCalc.Data
         {
             return new CostEntryDetails
             {
-                TotalPrice = TotalPrice,
+                TotalAmount = TotalAmount,
                 UnitCount = UnitCount,
                 DiscountsInUnits = new List<decimal>(DiscountsInUnits)
             };
@@ -333,7 +333,7 @@ namespace UCalc.Data
     {
         public DateTime StartDate { get; set; }
         public DateTime EndDate { get; set; }
-        public decimal Price { get; set; }
+        public decimal Amount { get; set; }
         public CostEntryDetails Details { get; set; }
 
         public CostEntry()
@@ -343,7 +343,7 @@ namespace UCalc.Data
 
         private bool Equals(CostEntry other)
         {
-            return StartDate.Equals(other.StartDate) && EndDate.Equals(other.EndDate) && Price == other.Price &&
+            return StartDate.Equals(other.StartDate) && EndDate.Equals(other.EndDate) && Amount == other.Amount &&
                    Details.Equals(other.Details);
         }
 
@@ -360,7 +360,7 @@ namespace UCalc.Data
             {
                 StartDate = StartDate,
                 EndDate = EndDate,
-                Price = Price,
+                Amount = Amount,
                 Details = Details?.Clone()
             };
         }
@@ -373,6 +373,24 @@ namespace UCalc.Data
         Size
     }
 
+    public static class CostDivisions
+    {
+        public static string AsString(this CostDivision division)
+        {
+            switch (division)
+            {
+                case CostDivision.Person:
+                    return "Pro Person";
+                case CostDivision.Flat:
+                    return "Pro Wohnung";
+                case CostDivision.Size:
+                    return "Pro m²";
+                default:
+                    throw new InvalidOperationException();
+            }
+        }
+    }
+
     public class Cost
     {
         public string Name { get; set; }

ucalc/Models/CostEntriesProperty.cs

@@ -0,0 +1,35 @@
+using System.Collections.Generic;
+using System.Linq;
+using UCalc.Data;
+
+namespace UCalc.Models
+{
+    public class CostEntriesProperty : MultiProperty<CostEntryProperty>
+    {
+        public CostEntriesProperty(Model model, Property parent, IEnumerable<CostEntry> data) : base(model, parent,
+            "Zeiträume: Geben Sie einen oder mehr Zeiträume an.")
+        {
+            foreach (var entry in data)
+            {
+                Add(new CostEntryProperty(model, this, entry));
+            }
+        }
+
+        public void Add()
+        {
+            var entry = new CostEntryProperty(Model, this, new CostEntry());
+            entry.StartDate.Value = null;
+            entry.EndDate.Value = null;
+            base.Add(entry);
+        }
+
+        public new void Remove(CostEntryProperty entry)
+        {
+            using var validator = Model.BeginValidation();
+
+            base.Remove(entry);
+
+            validator.ValidateRange(Properties.Select(otherEntry => otherEntry.EndDate));
+        }
+    }
+}

ucalc/Models/CostEntryProperty.cs

@@ -0,0 +1,87 @@
+using System;
+using System.Linq;
+using UCalc.Controls;
+using UCalc.Data;
+
+namespace UCalc.Models
+{
+    public class DateProperty : ValueProperty<DateTime?>
+    {
+        public DateProperty(Model model, Property parent, string name, DateTime value) : base(model, parent, name,
+            value)
+        {
+        }
+
+        protected override string ValidateValue()
+        {
+            var error = Value == null ? $"{Name}: Geben Sie einen Wert ein." : "";
+
+            using var validator = Model.BeginValidation();
+            validator.Validate(((CostEntryProperty) Parent).EndDate);
+
+            return error;
+        }
+    }
+
+    public class EndDateProperty : ValueProperty<DateTime?>
+    {
+        public EndDateProperty(Model model, Property parent, string name, DateTime value) : base(model, parent, name,
+            value)
+        {
+        }
+
+        protected override string ValidateValue()
+        {
+            try
+            {
+                if (Value == null)
+                {
+                    return $"{Name}: Geben Sie einen Wert ein.";
+                }
+
+                var startDate = ((CostEntryProperty) Parent).StartDate.Value;
+                if (startDate != null)
+                {
+                    if (startDate > Value)
+                    {
+                        return $"{Name}: Das Enddatum liegt vor dem Startdatum.";
+                    }
+
+                    foreach (var entry in ((CostProperty) Parent.Parent.Parent).Entries)
+                    {
+                        if (!ReferenceEquals(entry.EndDate, this) && entry.StartDate.Value != null &&
+                            entry.EndDate.Value != null &&
+                            startDate.Value.Intersects(Value.Value, entry.StartDate.Value.Value,
+                                entry.EndDate.Value.Value))
+                        {
+                            return $"{Name}: Dieser Zeitraum überschneidet sich mit einem anderen.";
+                        }
+                    }
+                }
+
+                return "";
+            }
+            finally
+            {
+                using var validator = Model.BeginValidation();
+                validator.ValidateRange(((CostProperty) Parent.Parent.Parent).Entries.Select(entry => entry.EndDate));
+            }
+        }
+    }
+
+    public class CostEntryProperty : NestedProperty
+    {
+        public DateProperty StartDate { get; }
+        public EndDateProperty EndDate { get; }
+        public PositiveDecimalProperty Amount { get; }
+
+        // TODO: Details
+
+        public CostEntryProperty(Model model, Property parent, CostEntry data) : base(model, parent)
+        {
+            StartDate = Add(new DateProperty(model, this, "Startdatum", data.StartDate));
+            EndDate = Add(new EndDateProperty(model, this, "Enddatum", data.EndDate));
+            Amount = Add(new PositiveDecimalProperty(model, this, "Betrag", data.Amount));
+        }
+    }
+}

ucalc/Models/CostProperty.cs

@@ -1,18 +1,97 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
 using UCalc.Data;
 
 namespace UCalc.Models
 {
+    public class AffectsAllProperty : AlwaysValidProperty<bool>
+    {
+        public AffectsAllProperty(Model model, Property parent, string name, bool value) : base(model, parent, name,
+            value)
+        {
+        }
+
+        protected override string ValidateValue()
+        {
+            using var validator = Model.BeginValidation();
+            validator.Validate(((CostProperty) Parent).AffectedFlats);
+            return "";
+        }
+    }
+
+    public class AffectedFlatsProperty : Property
+    {
+        private const string NoFlatsError = "Betroffene Wohnungen: Es wurde keine Wohnung zugewiesen.";
+        private readonly HashSet<FlatProperty> _flats;
+        private readonly List<string> _errors;
+
+        public AffectedFlatsProperty(Model model, Property parent, IEnumerable<Flat> data,
+            IReadOnlyDictionary<Flat, FlatProperty> flatToProperty = null) : base(model, parent)
+        {
+            _flats = new HashSet<FlatProperty>();
+            _errors = new List<string>();
+
+            foreach (var flat in data)
+            {
+                _flats.Add(flatToProperty?[flat] ?? throw new InvalidOperationException());
+            }
+
+            Validate();
+        }
+
+        public override IReadOnlyList<string> Errors => _errors;
+
+        public void Add(FlatProperty flat)
+        {
+            if (!_flats.Add(flat))
+            {
+                return;
+            }
+
+            using var validator = Model.BeginValidation();
+            validator.Validate(this);
+            Modified = true;
+        }
+
+        public void Remove(FlatProperty flat)
+        {
+            if (!_flats.Remove(flat))
+            {
+                return;
+            }
+
+            using var validator = Model.BeginValidation();
+            validator.Validate(this);
+            Modified = true;
+        }
+
+        public bool Contains(FlatProperty flat)
+        {
+            return _flats.Contains(flat);
+        }
+
+        public sealed override void Validate()
+        {
+            _errors.Clear();
+
+            if (_flats.Count == 0 && !((CostProperty) Parent).AffectsAll.Value)
+            {
+                _errors.Add(NoFlatsError);
+            }
+
+            using var validator = Model.BeginValidation();
+            validator.Notify(this, "Errors");
+        }
+    }
+
     public class CostProperty : NestedProperty
     {
         public NotEmptyStringProperty Name { get; }
         public AlwaysValidProperty<int> Division { get; }
-        public AlwaysValidProperty<bool> AffectsAll { get; }
+        public AffectsAllProperty AffectsAll { get; }
-
         public AlwaysValidProperty<bool> IncludeUnrented { get; }
-
+        public AffectedFlatsProperty AffectedFlats { get; }
-        // TODO: public HashSet<Flat> AffectedFlats { get;  }
+        public CostEntriesProperty Entries { get; }
-        // TODO: public List<CostEntry> Entries { get;  }
         public AlwaysValidProperty<bool> DisplayInBill { get; }
 
         public CostProperty(Model model, Property parent, Cost cost,
@@ -20,9 +99,11 @@ namespace UCalc.Models
         {
             Name = Add(new NotEmptyStringProperty(model, this, "Name", cost.Name));
             Division = Add(new AlwaysValidProperty<int>(model, this, "Aufteilung", (int) cost.Division));
-            AffectsAll = Add(new AlwaysValidProperty<bool>(model, this, "Betrifft alle", cost.AffectsAll));
+            AffectsAll = Add(new AffectsAllProperty(model, this, "Betrifft alle", cost.AffectsAll));
+            AffectedFlats = Add(new AffectedFlatsProperty(model, this, cost.AffectedFlats, flatToProperty));
             IncludeUnrented =
                 Add(new AlwaysValidProperty<bool>(model, this, "Unvermietete einbeziehen", cost.IncludeUnrented));
+            Entries = Add(new CostEntriesProperty(model, this, cost.Entries));
             DisplayInBill = Add(new AlwaysValidProperty<bool>(model, this, "In Rechnung anzeigen", cost.DisplayInBill));
         }
     }

ucalc/Models/TenantProperty.cs

@@ -103,56 +103,61 @@ namespace UCalc.Models
         {
             _errors.Clear();
 
-            if (_flatProperties.Count == 0)
+            try
             {
-                _errors.Add(NoFlatsError);
+                if (_flatProperties.Count == 0)
-                return;
-            }
-
-            var entryDate = ((TenantProperty) Parent).EntryDate.Value;
-            var departureDate = ((TenantProperty) Parent).DepartureDate.Value;
-
-            foreach (var flatProperty in _flatProperties)
-            {
-                foreach (var tenant in Model.Root.Tenants)
                 {
-                    if (ReferenceEquals(this, tenant.RentedFlats))
+                    _errors.Add(NoFlatsError);
-                    {
+                    return;
-                        continue;
+                }
-                    }
 
-                    if (tenant.RentedFlats.IsRented(flatProperty, entryDate, departureDate))
+                var entryDate = ((TenantProperty) Parent).EntryDate.Value;
-                    {
+                var departureDate = ((TenantProperty) Parent).DepartureDate.Value;
-                        var error = $"Gemietete Wohnungen: Die Wohnung \"{flatProperty.Name.Value}\" ist bereits ";
 
-                        if (entryDate != null)
+                foreach (var flatProperty in _flatProperties)
+                {
+                    foreach (var tenant in Model.Root.Tenants)
+                    {
+                        if (ReferenceEquals(this, tenant.RentedFlats))
                         {
-                            if (departureDate != null)
+                            continue;
-                            {
-                                _errors.Add(
-                                    $"von {entryDate.Value.ToString(Constants.DateFormat)} - {departureDate.Value.ToString(Constants.DateFormat)} ");
-                            }
-                            else
-                            {
-                                _errors.Add($"seit dem {entryDate.Value.ToString(Constants.DateFormat)} ");
-                            }
-                        }
-                        else if (departureDate != null)
-                        {
-                            _errors.Add($"bis zum {departureDate.Value.ToString(Constants.DateFormat)} ");
                         }
 
-                        error += "an einen anderen Mieter vermietet.";
+                        if (tenant.RentedFlats.IsRented(flatProperty, entryDate, departureDate))
-                        _errors.Add(error);
+                        {
-                        break;
+                            var error = $"Gemietete Wohnungen: Die Wohnung \"{flatProperty.Name.Value}\" ist bereits ";
+
+                            if (entryDate != null)
+                            {
+                                if (departureDate != null)
+                                {
+                                    _errors.Add(
+                                        $"von {entryDate.Value.ToString(Constants.DateFormat)} - {departureDate.Value.ToString(Constants.DateFormat)} ");
+                                }
+                                else
+                                {
+                                    _errors.Add($"seit dem {entryDate.Value.ToString(Constants.DateFormat)} ");
+                                }
+                            }
+                            else if (departureDate != null)
+                            {
+                                _errors.Add($"bis zum {departureDate.Value.ToString(Constants.DateFormat)} ");
+                            }
+
+                            error += "an einen anderen Mieter vermietet.";
+                            _errors.Add(error);
+                            break;
+                        }
                     }
                 }
             }
+            finally
+            {
+                using var validator = Model.BeginValidation();
+                validator.Notify(this, "Errors");
 
-            using var validator = Model.BeginValidation();
+                validator.ValidateRange(Model.Root.Tenants);
-            validator.Notify(this, "Errors");
+            }
-
-            validator.ValidateRange(Model.Root.Tenants);
         }
 
         private bool IsRented(FlatProperty flat, DateTime? start, DateTime? end)