Dynamic data models - Rewrote the visualization to use leverage new core APIs

src/Artemis.Core/Models/Profile/DataModel/DataModelPath.cs

@@ -1,7 +1,9 @@
 using System;
+using System.Collections;
 using System.Collections.Generic;
 using System.Linq;
 using System.Linq.Expressions;
+using System.Reflection;
 using Artemis.Core.DataModelExpansions;
 
 namespace Artemis.Core
@@ -11,22 +13,29 @@ namespace Artemis.Core
     /// </summary>
     public class DataModelPath
     {
-        private readonly LinkedList<DataModelPathPart> _parts;
+        private readonly LinkedList<DataModelPathSegment> _segments;
 
-        internal DataModelPath(DataModel dataModel, string path)
+        /// <summary>
+        ///     Creates a new instance of the <see cref="DataModelPath" /> class
+        /// </summary>
+        /// <param name="dataModel">The data model at which this path starts</param>
+        /// <param name="path">A string representation of the <see cref="DataModelPath" /></param>
+        public DataModelPath(object dataModel, string path)
         {
-            DataModel = dataModel ?? throw new ArgumentNullException(nameof(dataModel));
+            Target = dataModel ?? throw new ArgumentNullException(nameof(dataModel));
             Path = path ?? throw new ArgumentNullException(nameof(path));
-            DataModelGuid = dataModel.PluginInfo.Guid;
 
-            _parts = new LinkedList<DataModelPathPart>();
+            if (string.IsNullOrWhiteSpace(Path))
+                throw new ArgumentException("Path cannot be empty");
+
+            _segments = new LinkedList<DataModelPathSegment>();
             Initialize(path);
         }
 
         /// <summary>
         ///     Gets the data model at which this path starts
         /// </summary>
-        public DataModel DataModel { get; }
+        public object Target { get; }
 
         /// <summary>
         ///     Gets a string representation of the <see cref="DataModelPath" />
@@ -34,49 +43,111 @@ namespace Artemis.Core
         public string Path { get; }
 
         /// <summary>
-        ///     Gets a boolean indicating whether all <see cref="Parts" /> are valid
+        ///     Gets a boolean indicating whether all <see cref="Segments" /> are valid
         /// </summary>
-        public bool IsValid => Parts.All(p => p.Type != DataModelPathPartType.Invalid);
+        public bool IsValid => Segments.All(p => p.Type != DataModelPathSegmentType.Invalid);
 
         /// <summary>
-        ///     Gets a read-only list of all parts of this path
+        ///     Gets a read-only list of all segments of this path
         /// </summary>
-        public IReadOnlyCollection<DataModelPathPart> Parts => _parts.ToList().AsReadOnly();
+        public IReadOnlyCollection<DataModelPathSegment> Segments => _segments.ToList().AsReadOnly();
 
-        internal Func<DataModel, object> Accessor { get; private set; }
+        /// <summary>
+        ///     Gets a boolean indicating whether this data model path can have an inner path because it points to a list
+        /// </summary>
+        public bool CanHaveInnerPath => Segments.LastOrDefault()?.GetPropertyType()?.IsAssignableFrom(typeof(IList)) ?? false;
 
-        internal Guid DataModelGuid { get; set; }
+        /// <summary>
+        ///     Gets the inner path of this path, only available if this path points to a list
+        /// </summary>
+        public DataModelPath InnerPath { get; internal set; }
+
+        internal Func<object, object> Accessor { get; private set; }
+
+        public void SetInnerPath(string path)
+        {
+            if (!CanHaveInnerPath)
+            {
+                var type = Segments.LastOrDefault()?.GetPropertyType();
+                throw new ArtemisCoreException($"Cannot set an inner path on a data model path if it does not point to a list (value is of type: {type?.Name})");
+            }
+
+            InnerPath = new DataModelPath(GetValue(), path);
+        }
+
+        /// <summary>
+        ///     Gets the current value of the path
+        /// </summary>
+        public object GetValue()
+        {
+            return Accessor?.Invoke(Target);
+        }
+
+        /// <summary>
+        ///     Gets the property info of the property this path points to
+        /// </summary>
+        /// <returns>If static, the property info. If dynamic, <c>null</c></returns>
+        public PropertyInfo GetPropertyInfo()
+        {
+            if (InnerPath != null)
+                return InnerPath.GetPropertyInfo();
+            return Segments.LastOrDefault()?.GetPropertyInfo();
+        }
+
+        /// <summary>
+        ///     Gets the type of the property this path points to
+        /// </summary>
+        /// <returns>If possible, the property type</returns>
+        public Type GetPropertyType()
+        {
+            if (InnerPath != null)
+                return InnerPath.GetPropertyType();
+            return Segments.LastOrDefault()?.GetPropertyType();
+        }
+
+        /// <summary>
+        ///     Gets the property description of the property this path points to
+        /// </summary>
+        /// <returns>If found, the data model property description</returns>
+        public DataModelPropertyAttribute GetPropertyDescription()
+        {
+            if (InnerPath != null)
+                return InnerPath.GetPropertyDescription();
+            return Segments.LastOrDefault()?.GetPropertyDescription();
+        }
 
         /// <inheritdoc />
         public override string ToString()
         {
+            if (InnerPath != null)
+                return $"{Path} > {InnerPath}";
             return Path;
         }
 
         private void Initialize(string path)
         {
-            var parts = path.Split(".");
-            for (var index = 0; index < parts.Length; index++)
+            var segments = path.Split(".");
+            for (var index = 0; index < segments.Length; index++)
             {
-                var identifier = parts[index];
-                var node = _parts.AddLast(new DataModelPathPart(this, identifier, string.Join('.', parts.Take(index + 1))));
+                var identifier = segments[index];
+                var node = _segments.AddLast(new DataModelPathSegment(this, identifier, string.Join('.', segments.Take(index + 1))));
                 node.Value.Node = node;
             }
 
-            var parameter = Expression.Parameter(typeof(DataModel), "dm");
-            Expression expression = Expression.Convert(parameter, DataModel.GetType());
+            var parameter = Expression.Parameter(typeof(object), "t");
+            Expression expression = Expression.Convert(parameter, Target.GetType());
             Expression nullCondition = null;
 
-            foreach (var part in _parts)
+            foreach (var segment in _segments)
             {
-                var notNull = Expression.NotEqual(expression, Expression.Constant(null));
+                var notNull = Expression.NotEqual(expression, Expression.Default(expression.Type));
                 nullCondition = nullCondition != null ? Expression.AndAlso(nullCondition, notNull) : notNull;
-                expression = part.Initialize(parameter, expression, nullCondition);
+                expression = segment.Initialize(parameter, expression, nullCondition);
                 if (expression == null)
                     return;
             }
 
-            Accessor = Expression.Lambda<Func<DataModel, object>>(
+            Accessor = Expression.Lambda<Func<object, object>>(
                 // Wrap with a null check
                 Expression.Condition(
                     nullCondition,

src/Artemis.Core/Models/Profile/DataModel/DataModelPathPart.cs

@@ -1,151 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.Linq.Expressions;
-using System.Reflection;
-using Artemis.Core.DataModelExpansions;
-
-namespace Artemis.Core
-{
-    /// <summary>
-    ///     Represents a part of a data model path
-    /// </summary>
-    public class DataModelPathPart
-    {
-        internal DataModelPathPart(DataModelPath dataModelPath, string identifier, string path)
-        {
-            DataModelPath = dataModelPath;
-            Identifier = identifier;
-            Path = path;
-        }
-
-        /// <summary>
-        ///     Gets the data model path this is a part of
-        /// </summary>
-        public DataModelPath DataModelPath { get; }
-
-        /// <summary>
-        ///     Gets the identifier that is associated with this part
-        /// </summary>
-        public string Identifier { get; }
-
-        /// <summary>
-        ///     Gets the path that leads to this part
-        /// </summary>
-        public string Path { get; }
-
-        /// <summary>
-        ///     Gets the type of data model this part of the path points to
-        /// </summary>
-        public DataModelPathPartType Type { get; private set; }
-
-        /// <summary>
-        ///     Gets the type of dynamic data model this path points to
-        ///     <para>Not used if the <see cref="Type" /> is <see cref="DataModelPathPartType.Static" /></para>
-        /// </summary>
-        public Type DynamicDataModelType { get; private set; }
-
-        /// <summary>
-        ///     Gets the previous part in the path
-        /// </summary>
-        public DataModelPathPart Previous => Node.Previous?.Value;
-
-        /// <summary>
-        ///     Gets the next part in the path
-        /// </summary>
-        public DataModelPathPart Next => Node.Next?.Value;
-
-        internal Func<DataModel, object> Accessor { get; set; }
-        internal LinkedListNode<DataModelPathPart> Node { get; set; }
-
-        /// <summary>
-        ///     Returns the current value of the path up to this part
-        /// </summary>
-        /// <returns></returns>
-        public object GetValue()
-        {
-            return Type == DataModelPathPartType.Invalid ? null : Accessor(DataModelPath.DataModel);
-        }
-
-        /// <inheritdoc />
-        public override string ToString()
-        {
-            return $"[{Type}] {Path}";
-        }
-
-        internal Expression Initialize(ParameterExpression parameter, Expression expression, Expression nullCondition)
-        {
-            var previousValue = Previous != null ? Previous.GetValue() : DataModelPath.DataModel;
-            if (previousValue == null)
-            {
-                Type = DataModelPathPartType.Invalid;
-                return null;
-            }
-
-            // Determine this part's type by looking for a dynamic data model with the identifier
-            if (previousValue is DataModel dataModel)
-            {
-                var hasDynamicDataModel = dataModel.DynamicDataModels.TryGetValue(Identifier, out var dynamicDataModel);
-                // If a dynamic data model is found the use that
-                if (hasDynamicDataModel)
-                    DetermineDynamicType(dynamicDataModel);
-                // Otherwise look for a static type
-                else
-                    DetermineStaticType(previousValue);
-            }
-            // Only data models can have dynamic types so if it is something else, its always going to be static
-            else
-                DetermineStaticType(previousValue);
-
-            return CreateExpression(parameter, expression, nullCondition);
-        }
-
-        private Expression CreateExpression(ParameterExpression parameter, Expression expression, Expression nullCondition)
-        {
-            if (Type == DataModelPathPartType.Invalid)
-            {
-                Accessor = null;
-                return null;
-            }
-
-            Expression accessorExpression;
-            // A static part just needs to access the property or filed
-            if (Type == DataModelPathPartType.Static)
-                accessorExpression = Expression.PropertyOrField(expression, Identifier);
-            // A dynamic part calls the generic method DataModel.DynamicChild<T> and provides the identifier as an argument
-            else
-            {
-                accessorExpression = Expression.Call(
-                    expression,
-                    nameof(DataModel.DynamicChild),
-                    new[] {DynamicDataModelType},
-                    Expression.Constant(Identifier)
-                );
-            }
-
-            Accessor = Expression.Lambda<Func<DataModel, object>>(
-                // Wrap with a null check
-                Expression.Condition(
-                    nullCondition,
-                    Expression.Convert(accessorExpression, typeof(object)),
-                    Expression.Convert(Expression.Default(accessorExpression.Type), typeof(object))
-                ),
-                parameter
-            ).Compile();
-
-            return accessorExpression;
-        }
-
-        private void DetermineDynamicType(DataModel dynamicDataModel)
-        {
-            Type = DataModelPathPartType.Dynamic;
-            DynamicDataModelType = dynamicDataModel.GetType();
-        }
-
-        private void DetermineStaticType(object previous)
-        {
-            var previousType = previous.GetType();
-            var property = previousType.GetProperty(Identifier, BindingFlags.Public | BindingFlags.Instance);
-            Type = property == null ? DataModelPathPartType.Invalid : DataModelPathPartType.Static;
-        }
-    }
-}

src/Artemis.Core/Models/Profile/DataModel/DataModelPathSegment.cs

@@ -0,0 +1,208 @@
+using System;
+using System.Collections.Generic;
+using System.Linq.Expressions;
+using System.Reflection;
+using Artemis.Core.DataModelExpansions;
+using Humanizer;
+
+namespace Artemis.Core
+{
+    /// <summary>
+    ///     Represents a segment of a data model path
+    /// </summary>
+    public class DataModelPathSegment
+    {
+        internal DataModelPathSegment(DataModelPath dataModelPath, string identifier, string path)
+        {
+            DataModelPath = dataModelPath;
+            Identifier = identifier;
+            Path = path;
+        }
+
+        /// <summary>
+        ///     Gets the data model path this is a segment of
+        /// </summary>
+        public DataModelPath DataModelPath { get; }
+
+        /// <summary>
+        ///     Gets the identifier that is associated with this segment
+        /// </summary>
+        public string Identifier { get; }
+
+        /// <summary>
+        ///     Gets the path that leads to this segment
+        /// </summary>
+        public string Path { get; }
+
+        /// <summary>
+        ///     Gets the type of data model this segment of the path points to
+        /// </summary>
+        public DataModelPathSegmentType Type { get; private set; }
+
+        /// <summary>
+        ///     Gets the type of dynamic data model this path points to
+        ///     <para>Not used if the <see cref="Type" /> is <see cref="DataModelPathSegmentType.Static" /></para>
+        /// </summary>
+        public Type DynamicDataModelType { get; private set; }
+
+        /// <summary>
+        ///     Gets the previous segment in the path
+        /// </summary>
+        public DataModelPathSegment Previous => Node.Previous?.Value;
+
+        /// <summary>
+        ///     Gets the next segment in the path
+        /// </summary>
+        public DataModelPathSegment Next => Node.Next?.Value;
+
+        internal Func<object, object> Accessor { get; set; }
+        internal LinkedListNode<DataModelPathSegment> Node { get; set; }
+
+        /// <summary>
+        ///     Returns the current value of the path up to this segment
+        /// </summary>
+        /// <returns></returns>
+        public object GetValue()
+        {
+            return Type == DataModelPathSegmentType.Invalid ? null : Accessor(DataModelPath.Target);
+        }
+
+        /// <inheritdoc />
+        public override string ToString()
+        {
+            return $"[{Type}] {Path}";
+        }
+
+        /// <summary>
+        ///     Gets the property info of the property this segment points to
+        /// </summary>
+        /// <returns>If static, the property info. If dynamic, <c>null</c></returns>
+        public PropertyInfo GetPropertyInfo()
+        {
+            // Dynamic types have no property and therefore no property info
+            if (Type == DataModelPathSegmentType.Dynamic)
+                return null;
+
+            // If this is the first segment in a path, the property is located on the data model
+            if (Previous == null)
+                return DataModelPath.Target.GetType().GetProperty(Identifier);
+            // If this is not the first segment in a path, the property is located on the previous segment
+            return Previous.GetValue()?.GetType().GetProperty(Identifier);
+        }
+
+        /// <summary>
+        ///     Gets the property description of the property this segment points to
+        /// </summary>
+        /// <returns>If found, the data model property description</returns>
+        public DataModelPropertyAttribute GetPropertyDescription()
+        {
+            // Dynamic types have a data model description
+            if (Type == DataModelPathSegmentType.Dynamic)
+                return ((DataModel) GetValue())?.DataModelDescription;
+
+            var propertyInfo = GetPropertyInfo();
+            if (propertyInfo == null)
+                return null;
+
+            // Static types may have one as an attribute
+            return (DataModelPropertyAttribute) Attribute.GetCustomAttribute(propertyInfo, typeof(DataModelPropertyAttribute)) ??
+                   new DataModelPropertyAttribute {Name = propertyInfo.Name.Humanize(), ResetsDepth = false};
+        }
+
+        /// <summary>
+        ///     Gets the type of the property this path points to
+        /// </summary>
+        /// <returns>If possible, the property type</returns>
+        public Type GetPropertyType()
+        {
+            // Prefer basing the type on the property info
+            var propertyInfo = GetPropertyInfo();
+            var type = propertyInfo?.PropertyType;
+            // Property info is not available on dynamic paths though, so fall back on the current value
+            if (propertyInfo == null)
+            {
+                var currentValue = GetValue();
+                if (currentValue != null)
+                    type = currentValue.GetType();
+            }
+
+            return type;
+        }
+
+        internal Expression Initialize(ParameterExpression parameter, Expression expression, Expression nullCondition)
+        {
+            var previousValue = Previous != null ? Previous.GetValue() : DataModelPath.Target;
+            if (previousValue == null)
+            {
+                Type = DataModelPathSegmentType.Invalid;
+                return null;
+            }
+
+            // Determine this segment's type by looking for a dynamic data model with the identifier
+            if (previousValue is DataModel dataModel)
+            {
+                var hasDynamicDataModel = dataModel.DynamicDataModels.TryGetValue(Identifier, out var dynamicDataModel);
+                // If a dynamic data model is found the use that
+                if (hasDynamicDataModel)
+                    DetermineDynamicType(dynamicDataModel);
+                // Otherwise look for a static type
+                else
+                    DetermineStaticType(previousValue);
+            }
+            // Only data models can have dynamic types so if it is something else, its always going to be static
+            else
+                DetermineStaticType(previousValue);
+
+            return CreateExpression(parameter, expression, nullCondition);
+        }
+
+        private Expression CreateExpression(ParameterExpression parameter, Expression expression, Expression nullCondition)
+        {
+            if (Type == DataModelPathSegmentType.Invalid)
+            {
+                Accessor = null;
+                return null;
+            }
+
+            Expression accessorExpression;
+            // A static segment just needs to access the property or filed
+            if (Type == DataModelPathSegmentType.Static)
+                accessorExpression = Expression.PropertyOrField(expression, Identifier);
+            // A dynamic segment calls the generic method DataModel.DynamicChild<T> and provides the identifier as an argument
+            else
+            {
+                accessorExpression = Expression.Call(
+                    expression,
+                    nameof(DataModel.DynamicChild),
+                    new[] {DynamicDataModelType},
+                    Expression.Constant(Identifier)
+                );
+            }
+
+            Accessor = Expression.Lambda<Func<object, object>>(
+                // Wrap with a null check
+                Expression.Condition(
+                    nullCondition,
+                    Expression.Convert(accessorExpression, typeof(object)),
+                    Expression.Convert(Expression.Default(accessorExpression.Type), typeof(object))
+                ),
+                parameter
+            ).Compile();
+
+            return accessorExpression;
+        }
+
+        private void DetermineDynamicType(DataModel dynamicDataModel)
+        {
+            Type = DataModelPathSegmentType.Dynamic;
+            DynamicDataModelType = dynamicDataModel.GetType();
+        }
+
+        private void DetermineStaticType(object previous)
+        {
+            var previousType = previous.GetType();
+            var property = previousType.GetProperty(Identifier, BindingFlags.Public | BindingFlags.Instance);
+            Type = property == null ? DataModelPathSegmentType.Invalid : DataModelPathSegmentType.Static;
+        }
+    }
+}

src/Artemis.Core/Models/Profile/DataModel/DataModelPathSegmentType.cs

@@ -3,7 +3,7 @@
     /// <summary>
     ///     Represents a type of data model path
     /// </summary>
-    public enum DataModelPathPartType
+    public enum DataModelPathSegmentType
     {
         /// <summary>
         ///     Represents an invalid data model type that points to a missing data model

src/Artemis.Core/Plugins/DataModelExpansions/DataModel.cs

@@ -68,7 +68,7 @@ namespace Artemis.Core.DataModelExpansions
             if (_dynamicDataModels.ContainsKey(key))
             {
                 throw new ArtemisCoreException($"Cannot add a dynamic data model with key '{key}' " +
-                                               "because the key is already in use on this data model.");
+                                               "because the key is already in use on by another dynamic property this data model.");
             }
 
             if (_dynamicDataModels.ContainsValue(dynamicDataModel))
@@ -78,6 +78,12 @@ namespace Artemis.Core.DataModelExpansions
                                                $"because the dynamic data model is already added with key '{existingKey}.");
             }
 
+            if (GetType().GetProperty(key) != null)
+            {
+                throw new ArtemisCoreException($"Cannot add a dynamic data model with key '{key}' " +
+                                               "because the key is already in use by a static property on this data model.");
+            }
+
             dynamicDataModel.PluginInfo = PluginInfo;
             dynamicDataModel.DataModelDescription = new DataModelPropertyAttribute
             {