9 files changed, 370 insertions, 8 deletions

diff --git a/OpenSim/Framework/IClientAPI.cs b/OpenSim/Framework/IClientAPI.cs
index fb32397..985e085 100644
--- a/OpenSim/Framework/IClientAPI.cs
+++ b/OpenSim/Framework/IClientAPI.cs
@@ -570,6 +570,8 @@ namespace OpenSim.Framework
         event UUIDNameRequest OnTeleportHomeRequest;
         
         event ScriptAnswer OnScriptAnswer;
+
+        event AgentSit OnUndo;
          
         LLVector3 StartPos { get; set; }
 
diff --git a/OpenSim/Framework/UndoStack.cs b/OpenSim/Framework/UndoStack.cs
new file mode 100644
index 0000000..0b97644
--- /dev/null
+++ b/OpenSim/Framework/UndoStack.cs
@@ -0,0 +1,128 @@
+/*
+ * Copyright (c) Contributors, http://opensimulator.org/
+ * See CONTRIBUTORS.TXT for a full list of copyright holders.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of the OpenSim Project nor the
+ *       names of its contributors may be used to endorse or promote products
+ *       derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace OpenSim.Framework
+{
+    /// <summary>
+    /// Undo stack.  Deletes entries beyond a certain capacity
+    /// </summary>
+    /// <typeparam name="T"></typeparam>
+    [Serializable]
+    public class UndoStack<T>
+    {
+
+        private int m_new = 1;
+        private int m_old = 0;
+        private T[] m_Undos;
+
+        public bool IsFull
+        {
+            get
+            {
+                return m_new == m_old;
+            }
+        }
+
+
+        public int Capacity
+        {
+            get
+            {
+                return m_Undos.Length - 1;
+            }
+        }
+
+       
+        public UndoStack(int capacity)
+        {
+            m_Undos = new T[capacity + 1];
+        }
+
+       public void Push(T item)
+        {
+            if (IsFull)
+            {
+                m_old++;
+                if (m_old >= m_Undos.Length)
+                    m_old -= m_Undos.Length;
+            }
+            if (++m_new >= m_Undos.Length)
+                m_new -= m_Undos.Length;
+            m_Undos[m_new] = item;
+        }
+
+        public T Pop()
+        {
+            if (Count > 0)
+            {
+                T deleted = m_Undos[m_new];
+                m_Undos[m_new--] = default(T);
+                if (m_new < 0)
+                    m_new += m_Undos.Length;
+                return deleted;
+            }
+            else
+                throw new InvalidOperationException("Cannot pop from emtpy stack");
+        }
+
+        public int Count
+        {
+            get
+            {
+                int count = m_new - m_old - 1;
+                if (count < 0)
+                    count += m_Undos.Length;
+                return count;
+            }
+        }
+
+
+        public T Peek()
+        {
+            return m_Undos[m_new];
+        }
+
+       
+        public void Clear()
+        {
+            if (Count > 0)
+            {
+                for (int i = 0; i < m_Undos.Length; i++)
+                {
+                    m_Undos[i] = default(T);
+                }
+                m_new = 1;
+                m_old = 0;
+            }
+        }
+
+    }
+}
\ No newline at end of file
diff --git a/OpenSim/Region/ClientStack/ClientView.cs b/OpenSim/Region/ClientStack/ClientView.cs
index 94de013..aac96d1 100644
--- a/OpenSim/Region/ClientStack/ClientView.cs
+++ b/OpenSim/Region/ClientStack/ClientView.cs
@@ -238,6 +238,7 @@ namespace OpenSim.Region.ClientStack
         private ScriptAnswer handlerScriptAnswer = null;
         private RequestPayPrice handlerRequestPayPrice = null;
         private ObjectDeselect handlerObjectDetach = null;
+        private AgentSit handlerOnUndo = null;
 
         /* Properties */
 
@@ -799,6 +800,7 @@ namespace OpenSim.Region.ClientStack
 
         public event ScriptAnswer OnScriptAnswer;
         public event RequestPayPrice OnRequestPayPrice;
+        public event AgentSit OnUndo;
 
         #region Scene/Avatar to Client
 
@@ -3884,6 +3886,23 @@ namespace OpenSim.Region.ClientStack
                         // That means multiple object perms may be updated in a single packet.
 
                         break;
+
+                    case PacketType.Undo:
+                        UndoPacket undoitem = (UndoPacket)Pack;
+                        if (undoitem.ObjectData.Length > 0)
+                        {
+                            for (int i = 0; i < undoitem.ObjectData.Length; i++)
+                            {
+                                LLUUID objiD = undoitem.ObjectData[i].ObjectID;
+                                handlerOnUndo = OnUndo;
+                                if (handlerOnUndo != null)
+                                {
+                                    handlerOnUndo(this, objiD);
+                                }
+
+                            }
+                        }
+                        break;
                     case PacketType.ObjectDuplicateOnRay:
                         ObjectDuplicateOnRayPacket dupeOnRay = (ObjectDuplicateOnRayPacket)Pack;
 
diff --git a/OpenSim/Region/Environment/Scenes/InnerScene.cs b/OpenSim/Region/Environment/Scenes/InnerScene.cs
index d00f601..8a48f6e 100644
--- a/OpenSim/Region/Environment/Scenes/InnerScene.cs
+++ b/OpenSim/Region/Environment/Scenes/InnerScene.cs
@@ -312,6 +312,20 @@ namespace OpenSim.Region.Environment.Scenes
             }
 
         }
+
+        public void HandleUndo(IClientAPI remoteClient, LLUUID primId)
+        {
+            if (primId != LLUUID.Zero)
+            {
+                SceneObjectPart part =  m_parentScene.GetSceneObjectPart(primId);
+                if (part != null)
+                    part.Undo();
+
+            }
+                
+
+        }
+
         /// <summary>
         /// Event Handling routine for Attach Object
         /// </summary>
diff --git a/OpenSim/Region/Environment/Scenes/Scene.cs b/OpenSim/Region/Environment/Scenes/Scene.cs
index a517e69..de4270f 100644
--- a/OpenSim/Region/Environment/Scenes/Scene.cs
+++ b/OpenSim/Region/Environment/Scenes/Scene.cs
@@ -78,6 +78,7 @@ namespace OpenSim.Region.Environment.Scenes
         private readonly Mutex updateLock;
         public bool m_physicalPrim;
         public bool m_seeIntoRegionFromNeighbor;
+        public int MaxUndoCount = 5;
         private int m_RestartTimerCounter;
         private readonly Timer m_restartTimer = new Timer(15000); // Wait before firing
         private int m_incrementsof15seconds = 0;
@@ -1628,6 +1629,7 @@ namespace OpenSim.Region.Environment.Scenes
             client.OnTeleportHomeRequest += TeleportClientHome;
 
             client.OnSetStartLocationRequest += SetHomeRezPoint;
+            client.OnUndo += m_innerScene.HandleUndo;
              
             EventManager.TriggerOnNewClient(client);
         }
diff --git a/OpenSim/Region/Environment/Scenes/SceneObjectGroup.cs b/OpenSim/Region/Environment/Scenes/SceneObjectGroup.cs
index ba318a8..4711701 100644
--- a/OpenSim/Region/Environment/Scenes/SceneObjectGroup.cs
+++ b/OpenSim/Region/Environment/Scenes/SceneObjectGroup.cs
@@ -378,6 +378,7 @@ namespace OpenSim.Region.Environment.Scenes
                                 part.RegionHandle = m_regionHandle;
 
                                 part.TrimPermissions();
+                                part.StoreUndoState();
                             }
                             break;
                         case XmlNodeType.EndElement:
@@ -436,6 +437,7 @@ namespace OpenSim.Region.Environment.Scenes
                         {
                             SceneObjectPart Part = SceneObjectPart.FromXml(reader);
                             AddPart(Part);
+                            Part.StoreUndoState();
                         }
                         else
                         {
@@ -703,6 +705,8 @@ namespace OpenSim.Region.Environment.Scenes
             m_rootPart.ApplyPhysics(m_rootPart.ObjectFlags, m_scene.m_physicalPrim);
             AttachToBackup();
             m_rootPart.ScheduleFullUpdate();
+            m_rootPart.ClearUndoState();
+           
         }
         public void DetachToInventoryPrep()
         {
@@ -731,6 +735,7 @@ namespace OpenSim.Region.Environment.Scenes
         private void SetPartAsNonRoot(SceneObjectPart part)
         {
             part.ParentID = m_rootPart.LocalId;
+            part.ClearUndoState();
         }
 
         /// <summary>
@@ -783,6 +788,7 @@ namespace OpenSim.Region.Environment.Scenes
                 try
                 {
                     m_parts.Add(part.UUID, part);
+                    
                 }
                 catch (Exception e)
                 {
@@ -803,6 +809,7 @@ namespace OpenSim.Region.Environment.Scenes
                     if (part.UUID != m_rootPart.UUID)
                     {
                         part.ParentID = m_rootPart.LocalId;
+                        
                     }
                 }
             }
@@ -815,10 +822,17 @@ namespace OpenSim.Region.Environment.Scenes
                 foreach (SceneObjectPart part in m_parts.Values)
                 {
                     part.UUID = LLUUID.Random();
+                    
                 }
             }
         }
-
+        // helper provided for parts.
+        public int GetSceneMaxUndo()
+        {
+            if (m_scene != null)
+                return m_scene.MaxUndoCount;
+            return 5;
+        }
         public void ResetChildPrimPhysicsPositions()
         {
             AbsolutePosition = AbsolutePosition;
@@ -845,12 +859,15 @@ namespace OpenSim.Region.Environment.Scenes
             {
                 SceneObjectPart part = GetChildPart(localId);
                 OnGrabPart(part, offsetPos, remoteClient);
+                
             }
         }
 
         public virtual void OnGrabPart(SceneObjectPart part, LLVector3 offsetPos, IClientAPI remoteClient)
         {
+            part.StoreUndoState();
             part.OnGrab(offsetPos, remoteClient);
+            
         }
 
         public virtual void OnGrabGroup(LLVector3 offsetPos, IClientAPI remoteClient)
@@ -1382,8 +1399,9 @@ namespace OpenSim.Region.Environment.Scenes
             {
                 m_parts.Add(newPart.UUID, newPart);
             }
-
+            
             SetPartAsNonRoot(newPart);
+            
         }
 
         /// <summary>
@@ -1758,6 +1776,7 @@ namespace OpenSim.Region.Environment.Scenes
                 {
                     LinkNonRootPart(part, oldGroupPosition, oldRootRotation);
                 }
+                part.ClearUndoState();
             }
 
             DetachFromBackup(objectGroup);
@@ -1781,7 +1800,7 @@ namespace OpenSim.Region.Environment.Scenes
         public void DelinkFromGroup(uint partID)
         {
             SceneObjectPart linkPart = GetChildPart(partID);
-
+            linkPart.ClearUndoState();
             if (null != linkPart)
             {
 //                m_log.DebugFormat(
diff --git a/OpenSim/Region/Environment/Scenes/SceneObjectPart.cs b/OpenSim/Region/Environment/Scenes/SceneObjectPart.cs
index 0db9b91..6cfe3e9 100644
--- a/OpenSim/Region/Environment/Scenes/SceneObjectPart.cs
+++ b/OpenSim/Region/Environment/Scenes/SceneObjectPart.cs
@@ -26,6 +26,7 @@
  */
 
 using System;
+using System.Collections;
 using System.Collections.Generic;
 using System.Drawing;
 using System.Runtime.Serialization;
@@ -106,6 +107,8 @@ namespace OpenSim.Region.Environment.Scenes
         [XmlIgnore] public LLVector3 m_attachedPos = LLVector3.Zero;
         [XmlIgnore] public LLUUID fromAssetID = LLUUID.Zero;
 
+        [XmlIgnore] public bool m_undoing = false;
+
         public Int32 CreationDate;
         public uint ParentID = 0;
 
@@ -123,6 +126,8 @@ namespace OpenSim.Region.Environment.Scenes
         public uint EveryoneMask = (uint)PermissionMask.None;
         public uint NextOwnerMask = (uint)PermissionMask.All;
 
+        private UndoStack<UndoState> m_undo = new UndoStack<UndoState>(5);
+
         public LLObject.ObjectFlags Flags = LLObject.ObjectFlags.None;
 
         public uint ObjectFlags
@@ -266,6 +271,40 @@ namespace OpenSim.Region.Environment.Scenes
             //return new LLQuaternion(axiomPartRotation.x, axiomPartRotation.y, axiomPartRotation.z, axiomPartRotation.w);
 
         }
+        
+        public void StoreUndoState()
+        {
+            if (!m_undoing)
+            {
+                if (m_parentGroup != null)
+                {
+                    if (m_undo.Count > 0)
+                    {
+                        UndoState last = m_undo.Peek();
+                        if (last != null)
+                        {
+                            if (last.Compare(this))
+                                return;
+                        }
+                    }
+
+
+                    if (m_parentGroup.GetSceneMaxUndo() > 0)
+                    {
+                        UndoState nUndo = new UndoState(this);
+                        
+                        m_undo.Push(nUndo);
+
+                    }
+                }
+            }
+        }
+
+        public void ClearUndoState()
+        {
+            m_undo.Clear();
+            StoreUndoState();
+        }
 
         public LLVector3 GroupPosition
         {
@@ -290,7 +329,9 @@ namespace OpenSim.Region.Environment.Scenes
                 return m_groupPosition;
             }
             set
-            {   
+            {
+                StoreUndoState();
+
                 m_groupPosition = value;
 
                 if (PhysActor != null)
@@ -334,7 +375,10 @@ namespace OpenSim.Region.Environment.Scenes
         public LLVector3 OffsetPosition
         {
             get { return m_offsetPosition; }
-            set { m_offsetPosition = value;
+            set
+            {
+                StoreUndoState();
+                m_offsetPosition = value;
             try
             {
                 // Hack to get the child prim to update world positions in the physics engine
@@ -380,6 +424,7 @@ namespace OpenSim.Region.Environment.Scenes
             }
             set
             {
+                StoreUndoState();
                 m_rotationOffset = value;
 
                 if (PhysActor != null)
@@ -650,7 +695,8 @@ namespace OpenSim.Region.Environment.Scenes
         {
             get { return m_shape.Scale; }
             set 
-            { 
+            {
+                StoreUndoState();
                 m_shape.Scale = value;
                 TriggerScriptChangedEvent(Changed.SCALE);
             }
@@ -759,7 +805,8 @@ namespace OpenSim.Region.Environment.Scenes
                       LLObject.ObjectFlags.CreateSelected;
 
             TrimPermissions();
-
+            //m_undo = new UndoStack<UndoState>(ParentGroup.GetSceneMaxUndo());
+            
             ScheduleFullUpdate();
         }
 
@@ -802,7 +849,7 @@ namespace OpenSim.Region.Environment.Scenes
             
             TrimPermissions();
             // ApplyPhysics();
-
+           
             ScheduleFullUpdate();
         }
 
@@ -1982,6 +2029,7 @@ namespace OpenSim.Region.Environment.Scenes
 
         public void UpdateRotation(LLQuaternion rot)
         {
+            //StoreUndoState();
             RotationOffset = new LLQuaternion(rot.X, rot.Y, rot.Z, rot.W);
             ScheduleTerseUpdate();
         }
@@ -2097,6 +2145,7 @@ namespace OpenSim.Region.Environment.Scenes
         /// <param name="scale"></param>
         public void Resize(LLVector3 scale)
         {
+            StoreUndoState();
             m_shape.Scale = scale;
             
             ScheduleFullUpdate();
@@ -2522,5 +2571,15 @@ namespace OpenSim.Region.Environment.Scenes
             info.AddValue("PayPrice", PayPrice);
         }
 
+
+        public void Undo()
+        {
+            if (m_undo.Count > 0)
+            {
+                UndoState goback = m_undo.Pop();
+                if (goback != null)
+                    goback.PlaybackState(this);
+            }
+        }
     }
 }
diff --git a/OpenSim/Region/Environment/Scenes/UndoState.cs b/OpenSim/Region/Environment/Scenes/UndoState.cs
new file mode 100644
index 0000000..65c8669
--- /dev/null
+++ b/OpenSim/Region/Environment/Scenes/UndoState.cs
@@ -0,0 +1,118 @@
+/*
+ * Copyright (c) Contributors, http://opensimulator.org/
+ * See CONTRIBUTORS.TXT for a full list of copyright holders.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of the OpenSim Project nor the
+ *       names of its contributors may be used to endorse or promote products
+ *       derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+using System;
+using System.Collections.Generic;
+using libsecondlife;
+
+namespace OpenSim.Region.Environment.Scenes
+{
+    public class UndoState
+    {
+        public LLVector3 Position = LLVector3.Zero;
+        public LLVector3 Scale = LLVector3.Zero;
+        public LLQuaternion Rotation = LLQuaternion.Identity;
+
+        public UndoState(LLVector3 pos, LLQuaternion rot, LLVector3 scale)
+        {
+            Position = pos;
+            Rotation = rot;
+            Scale = scale;
+        }
+        
+        public UndoState(SceneObjectPart part)
+        {
+            if (part != null)
+            {
+                if (part.ParentID == 0)
+                {
+                    Position = part.AbsolutePosition;
+                    Rotation = part.RotationOffset;
+                    
+                }
+                else
+                {
+                    Position = part.GroupPosition;
+                    Rotation = part.RotationOffset;
+                    Scale = part.Shape.Scale;
+
+                }
+            }
+        }
+
+        public bool Compare(SceneObjectPart part)
+        {
+            if (part != null)
+            {
+                if (part.ParentID == 0)
+                {
+                    if (Position == part.AbsolutePosition && Rotation == part.RotationOffset)
+                        return true;
+                    else
+                        return false;
+                }
+                else
+                {
+                    if (Position == part.GroupPosition && Rotation == part.RotationOffset && Scale == part.Shape.Scale)
+                        return true;
+                    else
+                        return false;
+
+                }
+            }
+            return false;
+        }
+
+        public void PlaybackState(SceneObjectPart part)
+        {
+            if (part != null)
+            {
+                part.m_undoing = true;
+                
+                if (part.ParentID == 0)
+                {
+                    part.ParentGroup.AbsolutePosition = Position;
+                    part.UpdateRotation(Rotation);
+                    part.ParentGroup.ScheduleGroupForTerseUpdate();
+                }
+                else
+                {
+                    part.OffsetPosition = Position;
+                    part.UpdateRotation(Rotation);
+                    part.Resize(Scale);
+                    part.ScheduleTerseUpdate();
+                }
+                part.m_undoing = false;
+                
+            }
+        }
+
+        public UndoState()
+        {
+        }
+    }
+}
diff --git a/OpenSim/Region/Examples/SimpleModule/MyNpcCharacter.cs b/OpenSim/Region/Examples/SimpleModule/MyNpcCharacter.cs
index 9e57da5..59a2fd8 100644
--- a/OpenSim/Region/Examples/SimpleModule/MyNpcCharacter.cs
+++ b/OpenSim/Region/Examples/SimpleModule/MyNpcCharacter.cs
@@ -171,6 +171,7 @@ namespace OpenSim.Region.Examples.SimpleModule
 
         public event ScriptAnswer OnScriptAnswer;
         public event RequestPayPrice OnRequestPayPrice;
+        public event AgentSit OnUndo;
 
 
 #pragma warning restore 67