+ SynchronizeCachedDatabase.cs: Synchronizes the local cache with the remote file. Applies merging if necessary.

+ Tests (not yet complete)

src/KeePassLib2Android/Serialization/IOConnection.cs

@@ -105,7 +105,8 @@ namespace KeePassLib.Serialization
 			// Not implemented and ignored in Mono < 2.10
 			try
 			{
-				request.CachePolicy = new RequestCachePolicy(RequestCacheLevel.NoCacheNoStore);
+				//deactivated. No longer supported in Mono 4.8? 
+				//request.CachePolicy = new RequestCachePolicy(RequestCacheLevel.NoCacheNoStore);
 			}
 			catch(NotImplementedException) { }
 			catch(Exception) { Debug.Assert(false); }

src/Kp2aBusinessLogic/IKp2aApp.cs

@@ -1,4 +1,5 @@
 using System;
+using Android.App;
 using Android.Content;
 using Android.OS;
 using KeePassLib.Serialization;
@@ -69,6 +70,7 @@ namespace keepass2android
 
 		IProgressDialog CreateProgressDialog(Context ctx);
 		IFileStorage GetFileStorage(IOConnectionInfo iocInfo);
-		
+
+		void TriggerReload(Context context);
     }
 }

src/Kp2aBusinessLogic/Io/CachingFileStorage.cs

@@ -118,7 +118,7 @@ namespace keepass2android.Io
 			try
 			{
 				if (!IsCached(ioc)
-				    || File.ReadAllText(VersionFilePath(ioc)) == File.ReadAllText(BaseVersionFilePath(ioc)))
+				    || GetLocalVersionHash(ioc) == GetBaseVersionHash(ioc))
 				{
 					return OpenFileForReadWhenNoLocalChanges(ioc, cachedFilePath);
 				}
@@ -141,7 +141,7 @@ namespace keepass2android.Io
 		{
 			//file is cached but has local modifications
 			//try to upload the changes if remote file doesn't have changes as well:
-			var hash = Calculate(ioc);
+			var hash = CalculateHash(ioc);
 
 			if (File.ReadAllText(BaseVersionFilePath(ioc)) == hash)
 			{
@@ -160,18 +160,25 @@ namespace keepass2android.Io
 			return File.OpenRead(cachedFilePath);
 		}
 
-		private string Calculate(IOConnectionInfo ioc)
+		public MemoryStream GetRemoteDataAndHash(IOConnectionInfo ioc, out string hash)
 		{
 			MemoryStream remoteData = new MemoryStream();
-			string hash;
 			using (
 				HashingStreamEx hashingRemoteStream = new HashingStreamEx(_cachedStorage.OpenFileForRead(ioc), false,
-				                                                          new SHA256Managed()))
+																		  new SHA256Managed()))
 			{
 				hashingRemoteStream.CopyTo(remoteData);
 				hashingRemoteStream.Close();
 				hash = MemUtil.ByteArrayToHexString(hashingRemoteStream.Hash);
 			}
+			remoteData.Position = 0;
+			return remoteData;
+		}
+
+		private string CalculateHash(IOConnectionInfo ioc)
+		{
+			string hash;
+			GetRemoteDataAndHash(ioc, out hash);
 			return hash;
 		}
 
@@ -203,17 +210,7 @@ namespace keepass2android.Io
 		{
 			try
 			{
-				//try to write to remote:
+				UpdateRemoteFile(cachedData, ioc, useFileTransaction, hash);
-				using (
-					IWriteTransaction remoteTrans = _cachedStorage.OpenWriteTransaction(ioc, useFileTransaction))
-				{
-					Stream remoteStream = remoteTrans.OpenFile();
-					cachedData.CopyTo(remoteStream);
-					remoteStream.Close();
-					remoteTrans.CommitWrite();
-				}
-				//success. Update base-version of cache:
-				File.WriteAllText(VersionFilePath(ioc), hash);
 			}
 			catch (Exception e)
 			{
@@ -224,6 +221,33 @@ namespace keepass2android.Io
 			}
 		}
 
+		private void UpdateRemoteFile(Stream cachedData, IOConnectionInfo ioc, bool useFileTransaction, string hash)
+		{
+			//try to write to remote:
+			using (
+				IWriteTransaction remoteTrans = _cachedStorage.OpenWriteTransaction(ioc, useFileTransaction))
+			{
+				Stream remoteStream = remoteTrans.OpenFile();
+				cachedData.CopyTo(remoteStream);
+				remoteStream.Close();
+				remoteTrans.CommitWrite();
+			}
+			//success. Update base-version of cache:
+			File.WriteAllText(BaseVersionFilePath(ioc), hash);
+			File.WriteAllText(VersionFilePath(ioc), hash);
+		}
+
+		public void UpdateRemoteFile(IOConnectionInfo ioc, bool useFileTransaction)
+		{
+			using (Stream cachedData = File.OpenRead(CachedFilePath(ioc)))
+			{
+				UpdateRemoteFile(cachedData, ioc, useFileTransaction, GetLocalVersionHash(ioc));	
+			}
+			
+		}
+
+		
+
 		private class CachedWriteTransaction: IWriteTransaction
 		{
 			private class CachedWriteMemoryStream : MemoryStream
@@ -231,6 +255,7 @@ namespace keepass2android.Io
 				private readonly IOConnectionInfo ioc;
 				private readonly CachingFileStorage _cachingFileStorage;
 				private readonly bool _useFileTransaction;
+				private bool _closed;
 
 				public CachedWriteMemoryStream(IOConnectionInfo ioc, CachingFileStorage cachingFileStorage, bool useFileTransaction)
 				{
@@ -242,6 +267,8 @@ namespace keepass2android.Io
 
 				public override void Close()
 				{
+					if (_closed) return;
+
 					//write file to cache:
 					//(note: this might overwrite local changes. It's assumed that a sync operation or check was performed before
 					string hash;
@@ -257,9 +284,20 @@ namespace keepass2android.Io
 					File.WriteAllText(_cachingFileStorage.VersionFilePath(ioc), hash);
 					//update file on remote. This might overwrite changes there as well, see above.
 					Position = 0;
-					_cachingFileStorage.TryUpdateRemoteFile(this, ioc, _useFileTransaction, hash);
+					if (_cachingFileStorage.IsCached(ioc))
-				
+					{
+						//if the file already is in the cache, it's ok if writing to remote fails.
+						_cachingFileStorage.TryUpdateRemoteFile(this, ioc, _useFileTransaction, hash);
+					}
+					else
+					{
+						//if not, we don't accept a failure (e.g. invalid credentials would always remain a problem)
+						_cachingFileStorage.UpdateRemoteFile(this, ioc, _useFileTransaction, hash);
+					}
+
 					base.Close();
+
+					_closed = true;
 				}
 
 			}
@@ -280,7 +318,18 @@ namespace keepass2android.Io
 			public void Dispose()
 			{
 				if (!_committed)
-					_memoryStream.Dispose();
+				{
+					try
+					{
+						_memoryStream.Dispose();
+					}
+					catch (ObjectDisposedException e)
+					{
+						Kp2aLog.Log("Ignoring exception in Dispose: "+e);
+					}
+					
+				}
+					
 			}
 
 			public Stream OpenFile()
@@ -321,5 +370,32 @@ namespace keepass2android.Io
 			return UrlUtil.StripExtension(
 				UrlUtil.GetFileName(ioc.Path));
 		}
+
+
+		public string GetBaseVersionHash(IOConnectionInfo ioc)
+		{
+			return File.ReadAllText(BaseVersionFilePath(ioc));
+		}
+		public string GetLocalVersionHash(IOConnectionInfo ioc)
+		{
+			return File.ReadAllText(VersionFilePath(ioc));
+		}
+		public bool HasLocalChanges(IOConnectionInfo ioc)
+		{
+			return IsCached(ioc)
+			       && GetLocalVersionHash(ioc) != GetBaseVersionHash(ioc);
+		}
+
+		public Stream OpenRemoteForReadIfAvailable(IOConnectionInfo ioc)
+		{
+			try
+			{
+				return _cachedStorage.OpenFileForRead(ioc);
+			}
+			catch (Exception)
+			{
+				return File.OpenRead(CachedFilePath(ioc));
+			}
+		}
 	}
 }

src/Kp2aBusinessLogic/Kp2aBusinessLogic.csproj

@@ -51,6 +51,7 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="database\SynchronizeCachedDatabase.cs" />
     <Compile Include="Io\BuiltInFileStorage.cs" />
     <Compile Include="Io\CachingFileStorage.cs" />
     <Compile Include="Io\IFileStorage.cs" />

src/Kp2aBusinessLogic/UiStringKey.cs

@@ -34,6 +34,11 @@ namespace keepass2android
 		yes,
 		no,
 		YesSynchronize, 
-		NoOverwrite
+		NoOverwrite,
+		SynchronizingCachedDatabase,
+		DownloadingRemoteFile,
+		UploadingFile,
+		FilesInSync,
+		SynchronizedDatabaseSuccessfully
     }
 }

src/Kp2aBusinessLogic/database/SynchronizeCachedDatabase.cs

@@ -0,0 +1,98 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Text;
+using Android.App;
+using Android.Content;
+using KeePassLib.Serialization;
+using keepass2android.Io;
+
+namespace keepass2android
+{
+	public class SynchronizeCachedDatabase: RunnableOnFinish 
+	{
+		private readonly Context _context;
+		private readonly IKp2aApp _app;
+
+		public SynchronizeCachedDatabase(Context context, IKp2aApp app, OnFinish finish)
+			: base(finish)
+		{
+			_context = context;
+			_app = app;
+		}
+
+		public override void Run()
+		{
+			try
+			{
+				IOConnectionInfo ioc = _app.GetDb().Ioc;
+				IFileStorage fileStorage = _app.GetFileStorage(ioc);
+				if (!(fileStorage is CachingFileStorage))
+				{
+					throw new Exception("Cannot sync a non-cached database!");
+				}
+				StatusLogger.UpdateMessage(UiStringKey.SynchronizingCachedDatabase);
+				CachingFileStorage cachingFileStorage = (CachingFileStorage) fileStorage;
+
+				//download file from remote location and calculate hash:
+				StatusLogger.UpdateSubMessage(_app.GetResourceString(UiStringKey.DownloadingRemoteFile));
+				string hash;
+				//todo: catch filenotfound and upload then
+				MemoryStream remoteData = cachingFileStorage.GetRemoteDataAndHash(ioc, out hash);
+
+				//todo: what happens if something fails here?
+
+				//check if remote file was modified:
+				if (cachingFileStorage.GetBaseVersionHash(ioc) != hash)
+				{
+					//remote file is unmodified
+					if (cachingFileStorage.HasLocalChanges(ioc))
+					{
+						//conflict! need to merge
+						SaveDb saveDb = new SaveDb(_context, _app, new ActionOnFinish((success, result) =>
+							{
+								if (!success)
+								{
+									Finish(false, result);
+								}
+								else
+								{
+									Finish(true, _app.GetResourceString(UiStringKey.SynchronizedDatabaseSuccessfully));
+								}
+							}), false, remoteData);
+						saveDb.Run();
+					}
+					else
+					{
+						//only the remote file was modified -> reload database.
+						//note: it's best to lock the database and do a complete reload here (also better for UI consistency in case something goes wrong etc.)
+						_app.TriggerReload(_context);
+						Finish(true);
+					}
+				}
+				else
+				{
+					//remote file is unmodified
+					if (cachingFileStorage.HasLocalChanges(ioc))
+					{
+						//but we have local changes -> upload:
+						StatusLogger.UpdateSubMessage(_app.GetResourceString(UiStringKey.UploadingFile));
+						cachingFileStorage.UpdateRemoteFile(ioc, _app.GetBooleanPreference(PreferenceKey.UseFileTransactions));
+						StatusLogger.UpdateSubMessage("");
+						Finish(true, _app.GetResourceString(UiStringKey.SynchronizedDatabaseSuccessfully));
+					}
+					else
+					{
+						//files are in sync: just set the result
+						Finish(true, _app.GetResourceString(UiStringKey.FilesInSync));
+					}
+				}
+			}
+			catch (Exception e)
+			{
+				Finish(false, e.Message);
+			}
+			
+		}
+	}
+}

src/Kp2aBusinessLogic/database/edit/SaveDB.cs

@@ -34,14 +34,38 @@ namespace keepass2android
 	public class SaveDb : RunnableOnFinish {
 		private readonly IKp2aApp _app;
 		private readonly bool _dontSave;
+
+		/// <summary>
+		/// stream for reading the data from the original file. If this is set to a non-null value, we know we need to sync
+		/// </summary>
+		private readonly Stream _streamForOrigFile;
 		private readonly Context _ctx;
 		private Thread _workerThread;
 
-		public SaveDb(Context ctx, IKp2aApp app, OnFinish finish, bool dontSave): base(finish) {
+		public SaveDb(Context ctx, IKp2aApp app, OnFinish finish, bool dontSave)
+			: base(finish)
+		{
 			_ctx = ctx;
 			_app = app;
 			_dontSave = dontSave;
 		}
+		
+		/// <summary>
+		/// Constructor for sync
+		/// </summary>
+		/// <param name="ctx"></param>
+		/// <param name="app"></param>
+		/// <param name="finish"></param>
+		/// <param name="dontSave"></param>
+		/// <param name="streamForOrigFile">Stream for reading the data from the (changed) original location</param>
+		public SaveDb(Context ctx, IKp2aApp app, OnFinish finish, bool dontSave, Stream streamForOrigFile)
+			: base(finish)
+		{
+			_ctx = ctx;
+			_app = app;
+			_dontSave = dontSave;
+			_streamForOrigFile = streamForOrigFile;
+		}
 
 		public SaveDb(Context ctx, IKp2aApp app, OnFinish finish)
 			: base(finish)
@@ -63,18 +87,25 @@ namespace keepass2android
 					IOConnectionInfo ioc = _app.GetDb().Ioc;
 					IFileStorage fileStorage = _app.GetFileStorage(ioc);
 
-					if ((!_app.GetBooleanPreference(PreferenceKey.CheckForFileChangesOnSave))
+					if (_streamForOrigFile == null)
-						|| (_app.GetDb().KpDatabase.HashOfFileOnDisk == null)) //first time saving
 					{
-						PerformSaveWithoutCheck(fileStorage, ioc);
+						if ((!_app.GetBooleanPreference(PreferenceKey.CheckForFileChangesOnSave))
-						Finish(true);
+							|| (_app.GetDb().KpDatabase.HashOfFileOnDisk == null)) //first time saving
-						return;
+						{
+							PerformSaveWithoutCheck(fileStorage, ioc);
+							Finish(true);
+							return;
+						}	
 					}
+					
 
 
 
-					if (fileStorage.CheckForFileChangeFast(ioc, _app.GetDb().LastFileVersion)  //first try to use the fast change detection
+					if (
-						|| (FileHashChanged(ioc, _app.GetDb().KpDatabase.HashOfFileOnDisk))) //if that fails, hash the file and compare:
+						(_streamForOrigFile != null)
+						|| fileStorage.CheckForFileChangeFast(ioc, _app.GetDb().LastFileVersion)  //first try to use the fast change detection
+						|| (FileHashChanged(ioc, _app.GetDb().KpDatabase.HashOfFileOnDisk)) //if that fails, hash the file and compare:
+						)
 					{
 
 						//ask user...
@@ -183,12 +214,28 @@ namespace keepass2android
 			pwImp.MemoryProtection = pwDatabase.MemoryProtection.CloneDeep();
 			pwImp.MasterKey = pwDatabase.MasterKey;
 			KdbxFile kdbx = new KdbxFile(pwImp);
-			kdbx.Load(fileStorage.OpenFileForRead(ioc), KdbpFile.GetFormatToUse(ioc), null);
+			kdbx.Load(GetStreamForBaseFile(fileStorage, ioc), KdbpFile.GetFormatToUse(ioc), null);
 
 			pwDatabase.MergeIn(pwImp, PwMergeMethod.Synchronize, null); 
 
 		}
 
+		private Stream GetStreamForBaseFile(IFileStorage fileStorage, IOConnectionInfo ioc)
+		{
+			//if we have the original file already available: use it
+			if (_streamForOrigFile != null)
+				return _streamForOrigFile;
+
+			//if the file storage caches, it might return the local data in case of a conflict. This would result in data loss
+			// so we need to ensure we get the data from remote (only if the remote file is available. if not, we won't overwrite anything)
+			CachingFileStorage cachingFileStorage = fileStorage as CachingFileStorage;
+			if (cachingFileStorage != null)
+			{
+				return cachingFileStorage.OpenRemoteForReadIfAvailable(ioc);
+			}
+			return fileStorage.OpenFileForRead(ioc);
+		}
+
 		private void PerformSaveWithoutCheck(IFileStorage fileStorage, IOConnectionInfo ioc)
 		{
 			StatusLogger.UpdateSubMessage("");

src/Kp2aKeyboardBinding/Kp2aKeyboardBinding.csproj

@@ -53,6 +53,7 @@
   <ItemGroup>
     <None Include="Additions\AboutAdditions.txt" />
     <None Include="Jars\AboutJars.txt" />
+    <LibraryProjectZip Include="project.zip" />
   </ItemGroup>
   <ItemGroup>
     <TransformFile Include="Transforms\EnumFields.xml" />
@@ -60,9 +61,4 @@
     <TransformFile Include="Transforms\Metadata.xml" />
   </ItemGroup>
   <Import Project="$(MSBuildExtensionsPath)\Novell\Xamarin.Android.Bindings.targets" />
-  <ItemGroup>
-    <LibraryProjectZip Include="..\java\KP2ASoftKeyboard\project.zip">
-      <Link>project.zip</Link>
-    </LibraryProjectZip>
-  </ItemGroup>
 </Project>

src/Kp2aKeyboardBinding/Transforms/Metadata.xml

@@ -1,4 +1,5 @@
 <metadata>
+	<remove-node path="/api/package[@name='keepass2android.softkeyboard']/class[@name='KP2AKeyboard']" />
 	<!--
   This sample removes the class: android.support.v4.content.AsyncTaskLoader.LoadTask:
   <remove-node path="/api/package[@name='android.support.v4.content']/class[@name='AsyncTaskLoader.LoadTask']" />

src/Kp2aUnitTests/Kp2aUnitTests.csproj

@@ -15,6 +15,7 @@
     <AndroidApplication>true</AndroidApplication>
     <AndroidResgenFile>Resources\Resource.Designer.cs</AndroidResgenFile>
     <GenerateSerializationAssemblies>Off</GenerateSerializationAssemblies>
+    <AndroidManifest>Properties\AndroidManifest.xml</AndroidManifest>
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
     <DebugSymbols>true</DebugSymbols>
@@ -58,16 +59,19 @@
   <ItemGroup>
     <Compile Include="ProgressDialogStub.cs" />
     <Compile Include="TestBase.cs" />
+    <Compile Include="TestCacheSupervisor.cs" />
     <Compile Include="TestDrawableFactory.cs" />
     <Compile Include="TestCreateDb.cs" />
     <Compile Include="MainActivity.cs" />
     <Compile Include="Resources\Resource.Designer.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
+    <Compile Include="TestFileStorage.cs" />
     <Compile Include="TestKp2aApp.cs" />
     <Compile Include="TestLoadDb.cs" />
     <Compile Include="TestLoadDbCredentials.cs" />
     <Compile Include="TestCachingFileStorage.cs" />
     <Compile Include="TestSaveDb.cs" />
+    <Compile Include="TestSynchronizeCachedDatabase.cs" />
   </ItemGroup>
   <ItemGroup>
     <None Include="Resources\AboutResources.txt" />
@@ -96,6 +100,9 @@
       <Name>MonoDroidUnitTesting</Name>
     </ProjectReference>
   </ItemGroup>
+  <ItemGroup>
+    <TransformFile Include="Properties\AndroidManifest.xml" />
+  </ItemGroup>
   <Import Project="$(MSBuildExtensionsPath)\Xamarin\Android\Xamarin.Android.CSharp.targets" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
      Other similar extension points exist, see Microsoft.Common.targets.

src/Kp2aUnitTests/MainActivity.cs

@@ -18,8 +18,8 @@ namespace Kp2aUnitTests
         {
             TestRunner runner = new TestRunner();
             // Run all tests from this assembly
-            //runner.AddTests(Assembly.GetExecutingAssembly());
+            runner.AddTests(Assembly.GetExecutingAssembly());
-			runner.AddTests(new List<Type> { typeof(TestCachingFileStorage) });
+			//runner.AddTests(new List<Type> { typeof(TestSynchronizeCachedDatabase) });
 			//runner.AddTests(typeof(TestCachingFileStorage).GetMethod("TestSaveToRemote"));
 			//runner.AddTests(typeof(TestLoadDb).GetMethod("TestLoadKdbpWithPasswordOnly"));
 			//runner.AddTests(typeof(TestSaveDb).GetMethod("TestLoadKdbxAndSaveKdbp_TestIdenticalFiles"));

src/Kp2aUnitTests/Properties/AndroidManifest.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+	<uses-sdk android:minSdkVersion="8" android:targetSdkVersion="8" />
+	<application></application>
+</manifest>

src/Kp2aUnitTests/TestBase.cs

@@ -61,9 +61,9 @@ namespace Kp2aUnitTests
 			get { return DefaultDirectory + "savedWithDesktop/"; }
 		}
 
-		protected IKp2aApp LoadDatabase(string filename, string password, string keyfile)
+		protected TestKp2aApp LoadDatabase(string filename, string password, string keyfile)
 		{
-			IKp2aApp app = new TestKp2aApp();
+			var app = CreateTestKp2aApp();
 			app.CreateNewDatabase();
 			bool loadSuccesful = false;
 			LoadDb task = new LoadDb(app, new IOConnectionInfo() { Path = filename }, password, keyfile, new ActionOnFinish((success, message) =>
@@ -81,6 +81,12 @@ namespace Kp2aUnitTests
 			return app;
 		}
 
+		protected virtual TestKp2aApp CreateTestKp2aApp()
+		{
+			TestKp2aApp app = new TestKp2aApp();
+			return app;
+		}
+
 		protected void SaveDatabase(IKp2aApp app)
 		{
 			bool saveSuccesful = TrySaveDatabase(app);
@@ -104,16 +110,16 @@ namespace Kp2aUnitTests
 			return saveSuccesful;
 		}
 
-		protected IKp2aApp SetupAppWithDefaultDatabase()
+		protected TestKp2aApp SetupAppWithDefaultDatabase()
 		{
 			string filename = DefaultFilename;
 
 			return SetupAppWithDatabase(filename);
 		}
 
-		protected IKp2aApp SetupAppWithDatabase(string filename)
+		protected TestKp2aApp SetupAppWithDatabase(string filename)
 		{
-			IKp2aApp app = new TestKp2aApp();
+			TestKp2aApp app = CreateTestKp2aApp();
 
 			IOConnectionInfo ioc = new IOConnectionInfo {Path = filename};
 			Database db = app.CreateNewDatabase();

src/Kp2aUnitTests/TestCacheSupervisor.cs

@@ -0,0 +1,29 @@
+using System;
+using KeePassLib.Serialization;
+using keepass2android.Io;
+
+namespace Kp2aUnitTests
+{
+	class TestCacheSupervisor: ICacheSupervisor
+	{
+		public bool CouldntOpenFromRemoteCalled { get; set; }
+		public bool CouldntSaveToRemoteCalled { get; set; }
+		public bool NotifyOpenFromLocalDueToConflictCalled { get; set; }
+
+
+		public void CouldntSaveToRemote(IOConnectionInfo ioc, Exception e)
+		{
+			CouldntSaveToRemoteCalled = true;
+		}
+
+		public void CouldntOpenFromRemote(IOConnectionInfo ioc, Exception ex)
+		{
+			CouldntOpenFromRemoteCalled = true;
+		}
+
+		public void NotifyOpenFromLocalDueToConflict(IOConnectionInfo ioc)
+		{
+			NotifyOpenFromLocalDueToConflictCalled = true;
+		}
+	}
+}

src/Kp2aUnitTests/TestCachingFileStorage.cs

@@ -1,5 +1,4 @@
-using System;
+using System.Collections.Generic;
-using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Text;
@@ -20,118 +19,6 @@ namespace Kp2aUnitTests
 		private string _defaultCacheFileContents = "default contents";
 		private TestCacheSupervisor _testCacheSupervisor;
 
-		class TestCacheSupervisor: ICacheSupervisor
-		{
-			public bool CouldntOpenFromRemoteCalled { get; set; }
-			public bool CouldntSaveToRemoteCalled { get; set; }
-			public bool NotifyOpenFromLocalDueToConflictCalled { get; set; }
-
-
-			public void CouldntSaveToRemote(IOConnectionInfo ioc, Exception e)
-			{
-				CouldntSaveToRemoteCalled = true;
-			}
-
-			public void CouldntOpenFromRemote(IOConnectionInfo ioc, Exception ex)
-			{
-				CouldntOpenFromRemoteCalled = true;
-			}
-
-			public void NotifyOpenFromLocalDueToConflict(IOConnectionInfo ioc)
-			{
-				NotifyOpenFromLocalDueToConflictCalled = true;
-			}
-		}
-
-		public class TestFileStorage: IFileStorage
-		{
-			private BuiltInFileStorage _builtIn = new BuiltInFileStorage();
-
-			public bool Offline { get; set; }
-
-
-			public void DeleteFile(IOConnectionInfo ioc)
-			{
-				if (Offline)
-					throw new IOException("offline");
-				_builtIn.DeleteFile(ioc);
-			}
-
-			public bool CheckForFileChangeFast(IOConnectionInfo ioc, string previousFileVersion)
-			{
-				if (Offline)
-					return false;
-				return _builtIn.CheckForFileChangeFast(ioc, previousFileVersion);
-			}
-
-			public string GetCurrentFileVersionFast(IOConnectionInfo ioc)
-			{
-				if (Offline)
-					throw new IOException("offline");
-				return _builtIn.GetCurrentFileVersionFast(ioc);
-			}
-
-			public Stream OpenFileForRead(IOConnectionInfo ioc)
-			{
-				if (Offline)
-					throw new IOException("offline");
-				return _builtIn.OpenFileForRead(ioc);
-			}
-
-			public IWriteTransaction OpenWriteTransaction(IOConnectionInfo ioc, bool useFileTransaction)
-			{
-				if (Offline)
-					throw new IOException("offline");
-				return new TestFileTransaction(ioc, useFileTransaction, Offline);
-			}
-
-			public class TestFileTransaction : IWriteTransaction
-			{
-				private readonly bool _offline;
-				private readonly FileTransactionEx _transaction;
-
-				public TestFileTransaction(IOConnectionInfo ioc, bool useFileTransaction, bool offline)
-				{
-					_offline = offline;
-					_transaction = new FileTransactionEx(ioc, useFileTransaction);
-				}
-
-				public void Dispose()
-				{
-
-				}
-
-				public Stream OpenFile()
-				{
-					if (_offline)
-						throw new IOException("offline");
-					return _transaction.OpenWrite();
-				}
-
-				public void CommitWrite()
-				{
-					if (_offline)
-						throw new IOException("offline");
-					_transaction.CommitWrite();
-				}
-			}
-
-			public bool CompleteIoId()
-			{
-				throw new NotImplementedException();
-			}
-
-			public bool? FileExists()
-			{
-				throw new NotImplementedException();
-			}
-
-			public string GetFilenameWithoutPathAndExt(IOConnectionInfo ioc)
-			{
-				return _builtIn.GetFilenameWithoutPathAndExt(ioc);
-			}
-		}
-
 		/// <summary>
 		/// Tests correct behavior in case that either remote or cache are not available
 		/// </summary>

src/Kp2aUnitTests/TestFileStorage.cs

@@ -0,0 +1,96 @@
+using System;
+using System.IO;
+using KeePassLib.Serialization;
+using keepass2android.Io;
+
+namespace Kp2aUnitTests
+{
+	internal class TestFileStorage: IFileStorage
+	{
+		private BuiltInFileStorage _builtIn = new BuiltInFileStorage();
+
+		public bool Offline { get; set; }
+
+
+		public void DeleteFile(IOConnectionInfo ioc)
+		{
+			if (Offline)
+				throw new IOException("offline");
+			_builtIn.DeleteFile(ioc);
+		}
+
+		public bool CheckForFileChangeFast(IOConnectionInfo ioc, string previousFileVersion)
+		{
+			if (Offline)
+				return false;
+			return _builtIn.CheckForFileChangeFast(ioc, previousFileVersion);
+		}
+
+		public string GetCurrentFileVersionFast(IOConnectionInfo ioc)
+		{
+			if (Offline)
+				throw new IOException("offline");
+			return _builtIn.GetCurrentFileVersionFast(ioc);
+		}
+
+		public Stream OpenFileForRead(IOConnectionInfo ioc)
+		{
+			if (Offline)
+				throw new IOException("offline");
+			return _builtIn.OpenFileForRead(ioc);
+		}
+
+		public IWriteTransaction OpenWriteTransaction(IOConnectionInfo ioc, bool useFileTransaction)
+		{
+			if (Offline)
+				throw new IOException("offline");
+			return new TestFileTransaction(ioc, useFileTransaction, Offline);
+		}
+
+		public class TestFileTransaction : IWriteTransaction
+		{
+			private readonly bool _offline;
+			private readonly FileTransactionEx _transaction;
+
+			public TestFileTransaction(IOConnectionInfo ioc, bool useFileTransaction, bool offline)
+			{
+				_offline = offline;
+				_transaction = new FileTransactionEx(ioc, useFileTransaction);
+			}
+
+			public void Dispose()
+			{
+
+			}
+
+			public Stream OpenFile()
+			{
+				if (_offline)
+					throw new IOException("offline");
+				return _transaction.OpenWrite();
+			}
+
+			public void CommitWrite()
+			{
+				if (_offline)
+					throw new IOException("offline");
+				_transaction.CommitWrite();
+			}
+		}
+
+		public bool CompleteIoId()
+		{
+			throw new NotImplementedException();
+		}
+
+		public bool? FileExists()
+		{
+			throw new NotImplementedException();
+		}
+
+		public string GetFilenameWithoutPathAndExt(IOConnectionInfo ioc)
+		{
+			return _builtIn.GetFilenameWithoutPathAndExt(ioc);
+		}
+	}
+}

src/Kp2aUnitTests/TestKp2aApp.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using Android.App;
 using Android.Content;
 using Android.OS;
 using KeePassLib.Serialization;
@@ -22,6 +23,7 @@ namespace Kp2aUnitTests
 		private YesNoCancelResult _yesNoCancelResult = YesNoCancelResult.Yes;
 		private Dictionary<PreferenceKey, bool> _preferences = new Dictionary<PreferenceKey, bool>();
 
+
 		public void SetShutdown()
 		{
 			
@@ -40,7 +42,7 @@ namespace Kp2aUnitTests
 		public Database CreateNewDatabase()
 		{
 			TestDrawableFactory testDrawableFactory = new TestDrawableFactory();
-			_db = new Database(testDrawableFactory, new TestKp2aApp());
+			_db = new Database(testDrawableFactory, this);
 			return _db;
 
 		}
@@ -98,6 +100,9 @@ namespace Kp2aUnitTests
 		public Handler UiThreadHandler {
 			get { return null; } //ensure everything runs in the same thread. Otherwise the OnFinish-callback would run after the test has already finished (with failure)
 		}
+
+		public IFileStorage FileStorage { get; set; }
+
 		public IProgressDialog CreateProgressDialog(Context ctx)
 		{
 			return new ProgressDialogStub();
@@ -105,7 +110,20 @@ namespace Kp2aUnitTests
 
 		public IFileStorage GetFileStorage(IOConnectionInfo iocInfo)
 		{
-			return new BuiltInFileStorage();
+			return FileStorage;
+		}
+
+		
+		public bool TriggerReloadCalled;
+
+		public TestKp2aApp()
+		{
+			FileStorage = new BuiltInFileStorage();
+		}
+
+		public void TriggerReload(Context ctx)
+		{
+			TriggerReloadCalled = true;
 		}
 
 		public void SetYesNoCancelResult(YesNoCancelResult yesNoCancelResult)

src/Kp2aUnitTests/TestSynchronizeCachedDatabase.cs

@@ -0,0 +1,117 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Security.Cryptography;
+using System.Text;
+using Android.App;
+using Android.OS;
+using KeePassLib;
+using KeePassLib.Keys;
+using KeePassLib.Serialization;
+using KeePassLib.Utility;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using keepass2android;
+using keepass2android.Io;
+
+namespace Kp2aUnitTests
+{
+	[TestClass]
+	internal class TestSynchronizeCachedDatabase : TestBase
+	{
+		private TestCacheSupervisor _testCacheSupervisor = new TestCacheSupervisor();
+		private TestFileStorage _testFileStorage = new TestFileStorage();
+
+		[TestMethod]
+		public void TestTodos()
+		{
+			Assert.IsFalse(true, "Wird immer ManagedTransform benutzt??");
+			Assert.IsFalse(true, "TODOs in SyncDb");
+			Assert.IsFalse(true, "FileNotFound");
+			Assert.IsFalse(true, "Test merge files");
+		}
+
+		protected override TestKp2aApp CreateTestKp2aApp()
+		{
+			TestKp2aApp app = base.CreateTestKp2aApp();
+			app.FileStorage = new CachingFileStorage(_testFileStorage, "/mnt/sdcard/kp2atest/cache/", _testCacheSupervisor);
+			return app;
+		}
+
+		/// <summary>
+		/// Tests that synchronizing works if 
+		///  - no changes in remote and local db
+		///  - remote is offline -> error
+		///  - only local file was changed
+		/// </summary>
+		[TestMethod]
+		public void TestSimpleSyncCases()
+		{
+			
+			//create the default database:
+			TestKp2aApp app = SetupAppWithDefaultDatabase();
+			
+			
+			IOConnection.DeleteFile(new IOConnectionInfo {Path = DefaultFilename});
+			//save it and reload it so we have a base version ("remote" and in the cache)
+			SaveDatabase(app);
+			app = LoadDatabase(DefaultFilename, DefaultPassword, DefaultKeyfile);
+		
+			string resultMessage;
+			bool wasSuccessful;
+
+			//sync without changes on any side:
+			Synchronize(app, out wasSuccessful, out resultMessage);
+			Assert.IsTrue(wasSuccessful);
+			Assert.AreEqual(resultMessage, app.GetResourceString(UiStringKey.FilesInSync));
+
+			//go offline:
+			_testFileStorage.Offline = true;
+
+			//sync when offline (->error)
+			Synchronize(app, out wasSuccessful, out resultMessage);
+			Assert.IsFalse(wasSuccessful);
+			Assert.AreEqual(resultMessage, "offline");
+
+			//modify the database by adding a group:
+			app.GetDb().KpDatabase.RootGroup.AddGroup(new PwGroup(true, true, "TestGroup", PwIcon.Apple), true);
+			//save the database again (will be saved locally only)
+			SaveDatabase(app);
+			Assert.IsTrue(_testCacheSupervisor.CouldntSaveToRemoteCalled);
+			_testCacheSupervisor.CouldntSaveToRemoteCalled = false;
+
+			//go online again:
+			_testFileStorage.Offline = false;
+
+			//sync with local changes only (-> upload):
+			Synchronize(app, out wasSuccessful, out resultMessage);
+			Assert.IsTrue(wasSuccessful);
+			Assert.AreEqual(resultMessage, app.GetResourceString(UiStringKey.SynchronizedDatabaseSuccessfully));
+
+			//ensure both files are identical and up to date now:
+			_testFileStorage.Offline = true;
+			var appOfflineLoaded = LoadDatabase(DefaultFilename, DefaultPassword, DefaultKeyfile);
+			_testCacheSupervisor.CouldntOpenFromRemoteCalled = false;
+			_testFileStorage.Offline = false;
+			var appRemoteLoaded = LoadDatabase(DefaultFilename, DefaultPassword, DefaultKeyfile);
+			Assert.IsFalse(_testCacheSupervisor.CouldntOpenFromRemoteCalled);
+
+			AssertDatabasesAreEqual(app.GetDb().KpDatabase, appOfflineLoaded.GetDb().KpDatabase);
+			AssertDatabasesAreEqual(app.GetDb().KpDatabase, appRemoteLoaded.GetDb().KpDatabase);
+		}
+
+		private void Synchronize(TestKp2aApp app, out bool wasSuccessful, out string resultMessage)
+		{
+			bool success = false;
+			string result = null;
+			var sync = new SynchronizeCachedDatabase(Application.Context, app, new ActionOnFinish((_success, _result) =>
+				{ 
+					success = _success;
+					result = _result;
+				}));
+			sync.Run();
+			wasSuccessful = success;
+			resultMessage = result;
+		}
+	}
+}

src/keepass2android/Resources/values/strings.xml

@@ -270,7 +270,7 @@
 		* External database changes are detected and merged when saving\n
 		* Improved loading performance\n
 		* Improved search toolbar with suggestions\n
-		* New App logo!
+		* New App logo!\n
 		* Added support for .kdbp format for faster loading/saving\n
 		* Improved editing of extra strings and hidden display when protected\n
 		Thanks to Alex Vallat for his code contributions!\n

src/keepass2android/app/App.cs

@@ -125,33 +125,39 @@ namespace keepass2android
                 {
                     activity.SetResult(KeePass.ExitReloadDb);
                     activity.Finish();
+					//todo: return?
                 }
-                AlertDialog.Builder builder = new AlertDialog.Builder(activity);
+	            AskForReload(activity);
-                builder.SetTitle(activity.GetString(Resource.String.AskReloadFile_title));
-
-                builder.SetMessage(activity.GetString(Resource.String.AskReloadFile));
-
-                builder.SetPositiveButton(activity.GetString(Android.Resource.String.Yes), 
-                    (dlgSender, dlgEvt) =>
-                        {
-                            _db.ReloadRequested = true;
-                            activity.SetResult(KeePass.ExitReloadDb);
-                            activity.Finish();
-
-                        });
-
-                builder.SetNegativeButton(activity.GetString(Android.Resource.String.No), (dlgSender, dlgEvt) =>
-                    {
-
-                    });
-
-
-                Dialog dialog = builder.Create();
-                dialog.Show();
             }
         }
 
-        public void StoreOpenedFileAsRecent(IOConnectionInfo ioc, string keyfile)
+		private void AskForReload(Activity activity)
+		{
+			AlertDialog.Builder builder = new AlertDialog.Builder(activity);
+			builder.SetTitle(activity.GetString(Resource.String.AskReloadFile_title));
+
+			builder.SetMessage(activity.GetString(Resource.String.AskReloadFile));
+
+			builder.SetPositiveButton(activity.GetString(Android.Resource.String.Yes),
+				(dlgSender, dlgEvt) =>
+				{
+					_db.ReloadRequested = true;
+					activity.SetResult(KeePass.ExitReloadDb);
+					activity.Finish();
+
+				});
+
+			builder.SetNegativeButton(activity.GetString(Android.Resource.String.No), (dlgSender, dlgEvt) =>
+			{
+
+			});
+
+
+			Dialog dialog = builder.Create();
+			dialog.Show();
+		}
+
+		public void StoreOpenedFileAsRecent(IOConnectionInfo ioc, string keyfile)
         {
             FileDbHelper.CreateFile(ioc, keyfile);
         }
@@ -250,6 +256,11 @@ namespace keepass2android
 			return new BuiltInFileStorage();
 		}
 
+		public void TriggerReload(Context ctx)
+		{
+			AskForReload((Activity)ctx);
+		}
+
 
 		internal void OnTerminate()
         {

src/keepass2android/keepass2android.csproj

@@ -644,6 +644,7 @@
   <Import Project="$(MSBuildExtensionsPath)\Novell\Novell.MonoDroid.CSharp.targets" />
   <ItemGroup>
     <Folder Include="Assets\" />
+    <Folder Include="SupportLib\" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\KeePassLib2Android\KeePassLib2Android.csproj">
@@ -672,9 +673,6 @@
       </Properties>
     </MonoDevelop>
   </ProjectExtensions>
-  <ItemGroup>
-    <AndroidJavaLibrary Include="SupportLib\android-support-v4.jar" />
-  </ItemGroup>
   <ItemGroup>
     <AndroidNativeLibrary Include="..\java\kp2akeytransform\libs\armeabi\libfinal-key.so">
       <Link>libs\armeabi\libfinal-key.so</Link>