added AssetTypes.cs

git-svn-id: http://libopenmetaverse.googlecode.com/svn/trunk@1306 52acb1d6-8a22-11de-b505-999d5b087335

libsecondlife/AssetTypes.cs

@@ -0,0 +1,184 @@
+using System;
+using System.Text;
+
+namespace libsecondlife
+{
+    public abstract class Asset
+    {
+        private byte[] _AssetData = new byte[0];
+
+        private LLUUID _AssetID;
+        public LLUUID AssetID
+        {
+            get { return _AssetID; }
+            internal set
+            {
+                _AssetID = value;
+            }
+        }
+
+        private bool _DecodeNeeded;
+        /// <summary>
+        /// <code>true</code> if the asset's properties need to be decoded
+        /// from the asset's data byte array.
+        /// </summary>
+        public bool DecodeNeeded
+        {
+            private set { _DecodeNeeded = value; }
+            get { return _DecodeNeeded; }
+        }
+
+        private bool _EncodeNeeded;
+        /// <summary>
+        /// <code>true</code> if the asset's data byte array needs to be 
+        /// regenerated from the asset's properties, <code>false</code> otherwise.
+        /// </summary>
+        public bool EncodeNeeded
+        {
+            private set { _EncodeNeeded = value; }
+            get { return _EncodeNeeded; }
+        }
+
+        public Asset() { }
+
+        public void SetEncodedData(byte[] assetData)
+        {
+            byte[] copy = new byte[assetData.Length];
+            Buffer.BlockCopy(assetData, 0, copy, 0, assetData.Length);
+            _AssetData = copy;
+            DecodeNeeded = true;
+            EncodeNeeded = false;
+        }
+
+        public void GetEncodedData(byte[] dest, int off)
+        {
+            EncodeIfNeeded();
+            Buffer.BlockCopy(_AssetData, 0, dest, off, _AssetData.Length);
+        }
+
+        public byte[] GetEncodedData()
+        {
+            byte[] copy = new byte[_AssetData.Length];
+            GetEncodedData(copy, 0);
+            return copy;
+        }
+
+
+        /// <summary>
+        /// This method signals that the <code>AssetData</code> byte 
+        /// array no longer corresponds to the state of the Asset.
+        /// <remarks>
+        /// Derived classes should call this method if their properties
+        /// change. 
+        /// </remarks>
+        /// </summary>
+        protected void InvalidateEncodedData()
+        {
+            EncodeNeeded = true;
+        }
+
+        /// <summary>
+        /// Regenerates the <code>AssetData</code> array if and only if the properties
+        /// of the class have been modified.
+        /// <remarks>
+        /// Call this method instead of calling <code>Encode</code> directly.
+        /// </remarks>
+        /// </summary>
+        public void EncodeIfNeeded()
+        {
+            if (EncodeNeeded)
+            {
+                Encode(out _AssetData);
+                EncodeNeeded = false;
+            }
+        }
+
+        /// <summary>
+        /// Decodes the AssetData byte array, if and only if it hasn't been
+        /// decoded before.
+        /// <remarks>
+        /// Derived classes should call this method before returning a value in their
+        /// properties' getters and before setting the value in their properties' setters.
+        /// Call this method instead of calling <code>Decode</code> directly.
+        /// </remarks>
+        /// </summary>
+        public void DecodeIfNeeded()
+        {
+            if (DecodeNeeded)
+            {
+                Decode(_AssetData);
+                DecodeNeeded = false;
+            }
+        }
+
+        /// <summary>
+        /// Regenerates the <code>AssetData</code> byte array from the properties 
+        /// of the derived class.
+        /// </summary>
+        protected abstract void Encode(out byte[] newAssetData);
+
+        /// <summary>
+        /// Decodes the AssetData, placing it in appropriate properties of the derived
+        /// class.
+        /// </summary>
+        protected abstract void Decode(byte[] assetData);
+    }
+
+    public class AssetNotecard : Asset
+    {
+        private string _Text = null;
+        public string Text
+        {
+            get
+            {
+                DecodeIfNeeded();
+                return _Text;
+            }
+            set
+            {
+                DecodeIfNeeded();
+                _Text = value;
+                InvalidateEncodedData();
+            }
+        }
+
+        protected override void Encode(out byte[] newAssetData)
+        {
+            newAssetData = Helpers.StringToField(_Text);
+        }
+        
+        protected override void Decode(byte[] assetData)
+        {
+            _Text = Helpers.FieldToUTF8String(assetData);
+        }
+    }
+
+    public class AssetScript : Asset
+    {
+        private string _Source = null;
+        public string Source
+        {
+            get
+            {
+                DecodeIfNeeded();
+                return _Source;
+            }
+            set
+            {
+                DecodeIfNeeded();
+                _Source = value;
+                InvalidateEncodedData();
+            }
+        }
+
+        protected override void Encode(out byte[] newAssetData)
+        {
+            newAssetData = Helpers.StringToField(_Source);
+        }
+
+        protected override void Decode(byte[] assetData)
+        {
+            _Source = Helpers.FieldToUTF8String(assetData);
+        }
+    }
+}