Data bindings - Further implemented default converters

src/Artemis.Core/Models/Profile/LayerProperties/BaseLayerProperty.cs

@@ -32,7 +32,7 @@ namespace Artemis.Core
             get => _baseValue;
             set
             {
-                if (value.GetType() != GetPropertyType())
+                if (value != null && value.GetType() != GetPropertyType())
                     throw new ArtemisCoreException("Cannot update base value because of a type mismatch");
                 _baseValue = value;
             }
@@ -46,7 +46,7 @@ namespace Artemis.Core
             get => _currentValue;
             set
             {
-                if (value.GetType() != GetPropertyType())
+                if (value != null && value.GetType() != GetPropertyType())
                     throw new ArtemisCoreException("Cannot update current value because of a type mismatch");
                 _currentValue = value;
             }
@@ -61,7 +61,7 @@ namespace Artemis.Core
             get => _defaultValue;
             set
             {
-                if (value.GetType() != GetPropertyType())
+                if (value != null && value.GetType() != GetPropertyType())
                     throw new ArtemisCoreException("Cannot update default value because of a type mismatch");
                 _defaultValue = value;
             }
@@ -186,6 +186,9 @@ namespace Artemis.Core
         /// <returns>The newly created data binding</returns>
         public DataBinding EnableDataBinding(DataBindingRegistration dataBindingRegistration)
         {
+            if (dataBindingRegistration.LayerProperty != this)
+                throw new ArtemisCoreException("Cannot enable a data binding using a data binding registration of a different layer property");
+           
             var dataBinding = new DataBinding(dataBindingRegistration);
             _dataBindings.Add(dataBinding);
 

src/Artemis.Core/Models/Profile/LayerProperties/LayerProperty.cs

@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.Diagnostics;
 using System.Linq;
 using System.Linq.Expressions;
+using System.Reflection;
 using Artemis.Storage.Entities.Profile;
 using Newtonsoft.Json;
 
@@ -31,7 +32,7 @@ namespace Artemis.Core
         /// </summary>
         public new T BaseValue
         {
-            get => (T) base.BaseValue;
+            get => base.BaseValue != null ? (T) base.BaseValue : default;
             set
             {
                 if (Equals(base.BaseValue, value))
@@ -47,7 +48,7 @@ namespace Artemis.Core
         /// </summary>
         public new T CurrentValue
         {
-            get => (T) base.CurrentValue;
+            get => base.CurrentValue != null ? (T) base.CurrentValue : default;
             set => base.CurrentValue = value;
         }
 
@@ -57,7 +58,7 @@ namespace Artemis.Core
         /// </summary>
         public new T DefaultValue
         {
-            get => (T) base.DefaultValue;
+            get => base.DefaultValue != null ? (T) base.DefaultValue : default;
             set => base.DefaultValue = value;
         }
 
@@ -311,14 +312,35 @@ namespace Artemis.Core
 
         #region Data bindings
 
-        public void RegisterDataBindingProperty<TProperty>(Expression<Func<T, TProperty>> propertyLambda, IDataBindingConverter converter)
+        public void RegisterDataBindingProperty<TProperty>(Expression<Func<T, TProperty>> propertyLambda, DataBindingConverter converter)
         {
-            var propertyInfo = ReflectionUtilities.GetPropertyInfo(CurrentValue, propertyLambda);
+            // If the lambda references to itself, use the property info of public new T CurrentValue
+            PropertyInfo propertyInfo;
+            string path = null;
+            if (propertyLambda.Parameters[0] == propertyLambda.Body)
+            {
+                propertyInfo = GetType().GetProperties().FirstOrDefault(p => p.Name == nameof(CurrentValue) && p.PropertyType == typeof(T));
+            }
+            else
+            {
+                propertyInfo = ReflectionUtilities.GetPropertyInfo(CurrentValue, propertyLambda);
+                // Deconstruct the lambda
+                var current = (MemberExpression) propertyLambda.Body;
+                path = current.Member.Name;
+                while (current.Expression is MemberExpression memberExpression)
+                {
+                    path = current.Member.Name + "." + path;
+                    current = memberExpression;
+                }
+            }
+
             if (converter.SupportedType != propertyInfo.PropertyType)
+            {
                 throw new ArtemisCoreException($"Cannot register data binding property for property {propertyInfo.Name} " +
                                                "because the provided converter does not support the property's type");
+            }
 
-            _dataBindingRegistrations.Add(new DataBindingRegistration(this, propertyInfo, converter));
+            _dataBindingRegistrations.Add(new DataBindingRegistration(this, propertyInfo, converter, path));
         }
 
         private void UpdateDataBindings(double deltaTime)