Enhance ObjectFieldMultiplier with flexible field configuration and selective application

Projects/TerraTech/TerraTech/ObjectFieldMultiplier.cs

@@ -8,12 +8,36 @@ namespace TerraTech {
     /// Represents a field that can be multiplied by a configurable value
     /// </summary>
     /// <typeparam name="TValue">The type of the field value</typeparam>
+    public class FieldConfiguration<TValue> {
+        public string FieldName { get; }
+        public ConfigEntry<TValue> DefaultMultiplier { get; }
+        public Func<object, ConfigEntry<TValue>> ConditionalMultiplier { get; }
+
+        public FieldConfiguration(string fieldName, ConfigEntry<TValue> defaultMultiplier) {
+            FieldName = fieldName;
+            DefaultMultiplier = defaultMultiplier;
+        }
+
+        public FieldConfiguration(string fieldName, ConfigEntry<TValue> defaultMultiplier,
+                                  Func<object, ConfigEntry<TValue>> conditionalMultiplier) {
+            FieldName = fieldName;
+            DefaultMultiplier = defaultMultiplier;
+            ConditionalMultiplier = conditionalMultiplier;
+        }
+
+        public ConfigEntry<TValue> GetMultiplier(object instance) {
+            return ConditionalMultiplier?.Invoke(instance) ?? DefaultMultiplier;
+        }
+    }
+
     public class MultipliedField<TValue> {
         private readonly string _fieldName;
         private readonly ConfigEntry<TValue> _multiplier;
         private readonly Traverse _parentTraverse;
         private TValue _originalValue;
 
+        public string FieldName => _fieldName;
+
         public MultipliedField(string fieldName, ConfigEntry<TValue> multiplier, Traverse parentTraverse) {
             _fieldName = fieldName;
             _multiplier = multiplier;
@@ -99,32 +123,43 @@ namespace TerraTech {
     /// </summary>
     /// <typeparam name="T">The type of the object being managed</typeparam>
     public class MultipliedObject<T> {
+        private readonly T _instance;
         private readonly Traverse _objectTraverse;
-        private readonly List<MultipliedField<float>> _fields;
+        private readonly Dictionary<string, MultipliedField<float>> _fields;
 
         public MultipliedObject(T instance) {
+            _instance = instance;
             _objectTraverse = Traverse.Create(instance);
-            _fields = new List<MultipliedField<float>>();
+            _fields = new Dictionary<string, MultipliedField<float>>();
         }
 
-        public void AddField(string fieldName, ConfigEntry<float> multiplier) {
-            _fields.Add(new MultipliedField<float>(fieldName, multiplier, _objectTraverse));
+        public void AddField(FieldConfiguration<float> config) {
+            var multiplier = config.GetMultiplier(_instance);
+            _fields[config.FieldName] = new MultipliedField<float>(config.FieldName, multiplier, _objectTraverse);
         }
 
         public void CaptureFrom() {
-            foreach (var field in _fields) {
+            foreach (var field in _fields.Values) {
                 field.CaptureOriginal();
             }
         }
 
-        public void ApplyTo() {
-            foreach (var field in _fields) {
+        public void ApplyTo(IEnumerable<string> fieldNames = null) {
+            var fieldsToApply = fieldNames != null
+                                    ? fieldNames.Where(name => _fields.ContainsKey(name)).Select(name => _fields[name])
+                                    : _fields.Values;
+
+            foreach (var field in fieldsToApply) {
                 field.Apply();
             }
         }
 
-        public void RestoreTo() {
-            foreach (var field in _fields) {
+        public void RestoreTo(IEnumerable<string> fieldNames = null) {
+            var fieldsToRestore =
+                fieldNames != null ? fieldNames.Where(name => _fields.ContainsKey(name)).Select(name => _fields[name])
+                                   : _fields.Values;
+
+            foreach (var field in fieldsToRestore) {
                 field.Restore();
             }
         }
@@ -132,7 +167,7 @@ namespace TerraTech {
         public void LogValues(string prefix) {
             if (!Main.debug.Value)
                 return;
-            foreach (var field in _fields) {
+            foreach (var field in _fields.Values) {
                 field.LogValue(prefix);
             }
         }
@@ -182,25 +217,25 @@ namespace TerraTech {
             }
         }
 
-        public void ApplyAll() {
+        public void ApplyAll(IEnumerable<string> fieldNames = null) {
             if (Main.debug.Value)
                 Console.WriteLine("Modifying {0} {1}", _managedObjects.Count, typeof(T).Name);
             foreach (var instance in _managedObjects.Keys) {
-                RestoreTo(instance);
-                ApplyTo(instance);
+                RestoreTo(instance, fieldNames);
+                ApplyTo(instance, fieldNames);
             }
         }
 
-        private void ApplyTo(T instance) {
+        public void ApplyTo(T instance, IEnumerable<string> fieldNames = null) {
             MultipliedObject<T> obj;
             if (_managedObjects.TryGetValue(instance, out obj))
-                obj.ApplyTo();
+                obj.ApplyTo(fieldNames);
         }
 
-        private void RestoreTo(T instance) {
+        public void RestoreTo(T instance, IEnumerable<string> fieldNames = null) {
             MultipliedObject<T> obj;
             if (_managedObjects.TryGetValue(instance, out obj))
-                obj.RestoreTo();
+                obj.RestoreTo(fieldNames);
         }
     }
 }