Dynamic data models - WIP

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

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Linq.Expressions;
 using Artemis.Core.DataModelExpansions;
 
 namespace Artemis.Core
@@ -10,17 +11,51 @@ namespace Artemis.Core
     /// </summary>
     public class DataModelPath
     {
-        private readonly LinkedList<DataModelPathPart> _parts;
+        private readonly List<DataModelPathPart> _parts;
 
-        internal DataModelPath()
+        // TODO: Make internal
+        public DataModelPath(DataModel dataModel, string path)
         {
-            _parts = new LinkedList<DataModelPathPart>();
+            if (dataModel == null)
+                throw new ArgumentNullException(nameof(dataModel));
+            if (path == null)
+                throw new ArgumentNullException(nameof(path));
+
+            _parts = new List<DataModelPathPart>();
+
+            DataModel = dataModel;
+            DataModelGuid = dataModel.PluginInfo.Guid;
+
+            Initialize(path);
+        }
+
+        private void Initialize(string path)
+        {
+            var parts = path.Split(".");
+            foreach (var identifier in parts)
+                _parts.Add(new DataModelPathPart(this, identifier));
+
+            var parameter = Expression.Parameter(typeof(DataModel), "dm");
+            Expression expression = Expression.Convert(parameter, DataModel.GetType());
+            Expression nullCondition = null;
+            DataModelPathPart previous = null;
+
+            foreach (var part in _parts)
+            {
+                var notNull = Expression.NotEqual(expression, Expression.Constant(null));
+                nullCondition = nullCondition != null ? Expression.AndAlso(nullCondition, notNull) : notNull;
+                expression = part.Initialize(previous, parameter, expression, nullCondition);
+                if (expression == null)
+                    return;
+
+                previous = part;
+            }
         }
 
         /// <summary>
         ///     Gets the data model at which this path starts
         /// </summary>
-        public DataModel DataModel { get; private set; }
+        public DataModel DataModel { get; }
 
         /// <summary>
         ///     Gets a read-only list of all parts of this path
@@ -28,5 +63,23 @@ namespace Artemis.Core
         public IReadOnlyCollection<DataModelPathPart> Parts => _parts.ToList().AsReadOnly();
 
         internal Guid DataModelGuid { get; set; }
+
+        public string GetPathToPart(DataModelPathPart part)
+        {
+            var endIndex = _parts.IndexOf(part);
+            return endIndex < 0 ? null : string.Join('.', _parts.Take(endIndex + 1));
+        }
+
+        internal DataModelPathPart GetPartBefore(DataModelPathPart dataModelPathPart)
+        {
+            var index = _parts.IndexOf(dataModelPathPart);
+            return index > 0 ? _parts[index - 1] : null;
+        }
+
+        internal DataModelPathPart GetPartAfter(DataModelPathPart dataModelPathPart)
+        {
+            var index = _parts.IndexOf(dataModelPathPart);
+            return index < _parts.Count - 1 ? _parts[index + 1] : null;
+        }
     }
 }

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

@@ -1,18 +1,136 @@
-namespace Artemis.Core
+using System;
+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)
+        {
+            DataModelPath = dataModelPath;
+            Identifier = identifier;
+        }
+
+        /// <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; private set; }
+        public string Identifier { 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 => DataModelPath.GetPartBefore(this);
+
+        /// <summary>
+        ///     Gets the next part in the path
+        /// </summary>
+        public DataModelPathPart Next => DataModelPath.GetPartAfter(this);
+
+        internal Func<DataModel, object> Accessor { 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);
+        }
+
+        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)
+                );
+            }
+
+            var test = Expression.Lambda<Func<DataModel, object>>(
+                Expression.Condition(nullCondition, expression, Expression.Default(expression.Type)), // Wrap with a null check
+                parameter
+            );
+            Accessor = Expression.Lambda<Func<DataModel, object>>(
+                Expression.Condition(nullCondition, expression, Expression.Default(expression.Type)), // Wrap with a null check
+                parameter
+            ).Compile();
+
+            return accessorExpression;
+        }
+
+        internal Expression Initialize(DataModelPathPart previous, 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 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/DataModelPathPartType.cs

@@ -5,6 +5,11 @@
     /// </summary>
     public enum DataModelPathPartType
     {
+        /// <summary>
+        ///     Represents an invalid data model type that points to a missing data model
+        /// </summary>
+        Invalid,
+
         /// <summary>
         ///     Represents a static data model type that points to a data model defined in code
         /// </summary>

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

@@ -5,6 +5,7 @@ using System.Collections.ObjectModel;
 using System.Linq;
 using System.Reflection;
 using Artemis.Core.Modules;
+using Humanizer;
 
 namespace Artemis.Core.DataModelExpansions
 {
@@ -59,6 +60,11 @@ namespace Artemis.Core.DataModelExpansions
         /// <param name="description">An optional description</param>
         public void AddDynamicChild(DataModel dynamicDataModel, string key, string name = null, string description = null)
         {
+            if (dynamicDataModel == null)
+                throw new ArgumentNullException(nameof(dynamicDataModel));
+            if (key == null)
+                throw new ArgumentNullException(nameof(key));
+
             if (_dynamicDataModels.ContainsKey(key))
             {
                 throw new ArtemisCoreException($"Cannot add a dynamic data model with key '{key}' " +
@@ -72,6 +78,12 @@ namespace Artemis.Core.DataModelExpansions
                                                $"because the dynamic data model is already added with key '{existingKey}.");
             }
 
+            dynamicDataModel.PluginInfo = PluginInfo;
+            dynamicDataModel.DataModelDescription = new DataModelPropertyAttribute()
+            {
+                Name = name ?? key.Humanize(),
+                Description = description
+            };
             _dynamicDataModels.Add(key, dynamicDataModel);
         }
 
@@ -100,8 +112,8 @@ namespace Artemis.Core.DataModelExpansions
         /// </summary>
         /// <typeparam name="T">The type of data model you expect</typeparam>
         /// <param name="key">The unique key of the dynamic data model</param>
-        /// <returns>If found, the dynamic data model</returns>
-        public T GetDynamicChild<T>(string key) where T : DataModel
+        /// <returns>If found, the dynamic data model otherwise <c>null</c></returns>
+        public T DynamicChild<T>(string key) where T : DataModel
         {
             _dynamicDataModels.TryGetValue(key, out var value);
             return value as T;

src/Plugins/Artemis.Plugins.DataModelExpansions.TestData/DataModels/DynamicDataModel.cs

@@ -0,0 +1,15 @@
+using Artemis.Core.DataModelExpansions;
+
+namespace Artemis.Plugins.DataModelExpansions.TestData.DataModels
+{
+    public class DynamicDataModel : DataModel
+    {
+        public DynamicDataModel()
+        {
+            DynamicString = "Test 123";
+        }
+
+        [DataModelProperty(Description = "Descriptionnnnnn")]
+        public string DynamicString { get; set; }
+    }
+}

src/Plugins/Artemis.Plugins.DataModelExpansions.TestData/PluginDataModelExpansion.cs

@@ -1,5 +1,5 @@
 using System;
-using System.Linq;
+using Artemis.Core;
 using Artemis.Core.DataModelExpansions;
 using Artemis.Plugins.DataModelExpansions.TestData.DataModels;
 using SkiaSharp;
@@ -14,12 +14,13 @@ namespace Artemis.Plugins.DataModelExpansions.TestData
         {
             _rand = new Random();
             AddTimedUpdate(TimeSpan.FromSeconds(1), TimedUpdate);
-        }
 
-        private void TimedUpdate(double deltaTime)
-        {
-            DataModel.TestColorA = SKColor.FromHsv(_rand.Next(0, 360), 100, 100);
-            DataModel.TestColorB = SKColor.FromHsv(_rand.Next(0, 360), 100, 100);
+            DataModel.AddDynamicChild(new DynamicDataModel(), "Dynamic1", "Dynamic data model 1");
+
+            // var testPath1 = new DataModelPath(DataModel, "TemplateDataModelString");
+            var testPath2 = new DataModelPath(DataModel, "PluginSubDataModel.Number");
+            // var testPath3 = new DataModelPath(DataModel, "Dynamic1.DynamicString");
+            // var testPath4 = new DataModelPath(DataModel, "TemplateDataModelString");
         }
 
         public override void DisablePlugin()
@@ -30,6 +31,15 @@ namespace Artemis.Plugins.DataModelExpansions.TestData
         {
             // You can access your data model here and update it however you like
             DataModel.TemplateDataModelString = $"The last delta time was {deltaTime} seconds";
+
+            var dynamic = DataModel.DynamicChild<DynamicDataModel>("Dynamic1")?.DynamicString;
+            var dynamic2 = DataModel.DynamicChild<DynamicDataModel>("Dynamic2")?.DynamicString;
+        }
+
+        private void TimedUpdate(double deltaTime)
+        {
+            DataModel.TestColorA = SKColor.FromHsv(_rand.Next(0, 360), 100, 100);
+            DataModel.TestColorB = SKColor.FromHsv(_rand.Next(0, 360), 100, 100);
         }
     }
 }