[smuxi/experiments/sqlite: 7/27] [Engine] Added GetRange() implementation to MessageBufferBase based on class indexer

[Mirco M. M. Bauer <mmmbauer src gnome org>]

commit 9818683dc5da346af352e4cc9563b81c4a88e2c8
Author: Mirco Bauer <meebey meebey net>
Date:   Sun Feb 26 11:51:59 2012 +0100

    [Engine] Added GetRange() implementation to MessageBufferBase based on class indexer

 src/Engine/MessageBuffers/GitMessageBuffer.cs  |    5 -----
 src/Engine/MessageBuffers/MessageBufferBase.cs |   17 +++++++++++++++++
 2 files changed, 17 insertions(+), 5 deletions(-)
---
diff --git a/src/Engine/MessageBuffers/GitMessageBuffer.cs b/src/Engine/MessageBuffers/GitMessageBuffer.cs
index 75f2aa0..d72364c 100644
--- a/src/Engine/MessageBuffers/GitMessageBuffer.cs
+++ b/src/Engine/MessageBuffers/GitMessageBuffer.cs
@@ -192,11 +192,6 @@ namespace Smuxi.Engine
             throw new NotImplementedException ();
         }
 
-        public override System.Collections.Generic.IList<MessageModel> GetRange (int offset, int limit)
-        {
-            throw new NotImplementedException ();
-        }
-
         public override void Dispose()
         {
             Flush();
diff --git a/src/Engine/MessageBuffers/MessageBufferBase.cs b/src/Engine/MessageBuffers/MessageBufferBase.cs
index 823ab43..1667f88 100644
--- a/src/Engine/MessageBuffers/MessageBufferBase.cs
+++ b/src/Engine/MessageBuffers/MessageBufferBase.cs
@@ -66,6 +66,23 @@ namespace Smuxi.Engine
             ChatID = chatId;
         }
 
+        public virtual IList<MessageModel> GetRange(int offset, int limit)
+        {
+            if (offset < 0) {
+                throw new ArgumentException(
+                    "offset must be greater than or equal to 0.", "offset"
+                );
+            }
+
+            var bufferCount = Count;
+            var rangeCount = Math.Min(bufferCount, limit);
+            var range = new List<MessageModel>(rangeCount);
+            for (int i = offset; i < offset + limit && i < bufferCount; i++) {
+                range.Add(this[i]);
+            }
+            return range;
+        }
+
         IEnumerator IEnumerable.GetEnumerator()
         {
             return GetEnumerator();