Added ability to splice together BTs

Author: ashblue

Assets/FluidBehaviorTree/Scripts/BehaviorTree/Editor/TreeTest.cs

@@ -1,5 +1,4 @@
 using System.Collections.Generic;
-using Adnc.FluidBT.TaskParents;
 using Adnc.FluidBT.TaskParents.Composites;
 using Adnc.FluidBT.Tasks;
 using NSubstitute;
@@ -12,7 +11,7 @@ public class TreeTest {
         private Tree _tree;
 
         [SetUp]
-        public void SetBehaviorTree () {
+        public void BeforeEach () {
             _gameObject = new GameObject("BT");
             _tree = new Tree(_gameObject);
         }
@@ -29,6 +28,70 @@ public void It_should_set_the_root_node_Owner_by_default () {
             }
         }
 
+        public class SpliceMethod : TreeTest {
+            private GameObject _owner;
+            private Tree _treeAlt;
+            
+            [SetUp]
+            public void SetupTreeAlt () {
+                _owner = new GameObject("BT");
+                _treeAlt = new Tree(_owner);
+            }
+
+            [TearDown]
+            public void TeardownTreeAlt () {
+                Object.DestroyImmediate(_owner);
+            }
+            
+            [Test]
+            public void It_should_set_the_trees_root_as_a_child () {
+                _tree.Splice(_tree.Root, _treeAlt);
+                
+                Assert.AreEqual(_treeAlt.Root, _tree.Root.Children[0]);
+            }
+
+            [Test]
+            public void It_should_update_all_child_Owner_variables () {
+                var task = Substitute.For<ITask>();
+                task.Enabled.Returns(true);
+                
+                _treeAlt.AddNode(_treeAlt.Root, task);
+                var nodes = new List<ITask>{_treeAlt.Root, task};
+                
+                _tree.Splice(_tree.Root, _treeAlt);
+
+                nodes.ForEach((node) => Assert.AreEqual(_gameObject, node.Owner));
+            }
+            
+            [Test]
+            public void It_should_update_all_child_Owner_variables_with_nested_parents () {
+                var task = Substitute.For<ITask>();
+                task.Enabled.Returns(true);
+                var sequence = new Sequence();
+                
+                _treeAlt.AddNode(_treeAlt.Root, sequence);
+                _treeAlt.AddNode(sequence, task);
+                var nodes = new List<ITask>{sequence, _treeAlt.Root, task};
+                
+                _tree.Splice(_tree.Root, _treeAlt);
+
+                nodes.ForEach((node) => Assert.AreEqual(_gameObject, node.Owner));
+            }
+
+            [Test]
+            public void It_should_update_all_child_ParentTree_variables () {
+                var task = Substitute.For<ITask>();
+                task.Enabled.Returns(true);
+                
+                _treeAlt.AddNode(_treeAlt.Root, task);
+                var nodes = new List<ITask>{_treeAlt.Root, task};
+                
+                _tree.Splice(_tree.Root, _treeAlt);
+
+                nodes.ForEach((node) => Assert.AreEqual(_tree, node.ParentTree));
+            }
+        }
+
         public class AddNodeMethod : TreeTest {
             [Test]
             public void Parent_adds_the_child_reference () {

Assets/FluidBehaviorTree/Scripts/BehaviorTree/Tree.cs

@@ -1,4 +1,5 @@
-using Adnc.FluidBT.TaskParents;
+using System.Collections.Generic;
+using Adnc.FluidBT.TaskParents;
 using Adnc.FluidBT.Tasks;
 using UnityEngine;
 
@@ -12,8 +13,13 @@ public class Tree {
 
         public Tree (GameObject owner) {
             _owner = owner;
-            Root.ParentTree = this;
-            Root.Owner = owner;
+            SyncNodes(Root);
+        }
+        
+        public void Tick () {
+            if (Root.Update() != TaskStatus.Continue) {
+                TickCount++;
+            }
         }
 
         public void Reset () {
@@ -26,9 +32,24 @@ public void AddNode (ITaskParent parent, ITask child) {
             child.Owner = _owner;
         }
 
-        public void Tick () {
-            if (Root.Update() != TaskStatus.Continue) {
-                TickCount++;
+        public void Splice (ITaskParent parent, Tree tree) {
+            parent.AddChild(tree.Root);
+
+            SyncNodes(tree.Root);
+        }
+
+        private void SyncNodes (ITaskParent taskParent) {
+            taskParent.Owner = _owner;
+            taskParent.ParentTree = this;
+            
+            foreach (var child in taskParent.Children) {
+                child.Owner = _owner;
+                child.ParentTree = this;
+
+                var parent = child as ITaskParent;
+                if (parent != null) {
+                    SyncNodes(parent);
+                }
             }
         }
     }