allow importing database to internal folder

src/Kp2aBusinessLogic/Io/IoUtil.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Text;
+using Android.Content;
 using Java.IO;
 using KeePassLib.Serialization;
 
@@ -46,5 +47,50 @@ namespace keepass2android.Io
 			}
 			return iocParent;
 		}
+
+		public static bool IsInInternalDirectory(string path, Context context)
+		{
+			try
+			{
+				File filesDir = context.FilesDir.CanonicalFile;
+				File ourFile = new File(path).CanonicalFile;
+				//http://www.java2s.com/Tutorial/Java/0180__File/Checkswhetherthechilddirectoryisasubdirectoryofthebasedirectory.htm
+
+				File parentFile = ourFile;
+				while (parentFile != null)
+				{
+					if (filesDir.Equals(parentFile))
+					{
+						return true;
+					}
+					parentFile = parentFile.ParentFile;
+				}
+				return false;
+			}
+			catch (Exception e)
+			{
+				Kp2aLog.Log(e.ToString());
+				return false;
+			}
+			
+		}
+
+		public static void Copy(IOConnectionInfo targetIoc, IOConnectionInfo sourceIoc, IKp2aApp app)
+		{
+			IFileStorage sourceStorage = app.GetFileStorage(sourceIoc, false); //don't cache source. file won't be used ever again
+			IFileStorage targetStorage = app.GetFileStorage(targetIoc);
+
+			using (
+				var writeTransaction = targetStorage.OpenWriteTransaction(targetIoc,
+																		  app.GetBooleanPreference(
+																			  PreferenceKey.UseFileTransactions)))
+			{
+				using (var writeStream = writeTransaction.OpenFile())
+				{
+					sourceStorage.OpenFileForRead(sourceIoc).CopyTo(writeStream);
+				}
+				writeTransaction.CommitWrite();
+			}
+		}
 	}
 }

src/Kp2aBusinessLogic/Io/JavaFileStorage.cs

@@ -293,16 +293,6 @@ namespace keepass2android.Io
 			return false; //TODO implement. note, however, that we MAY return false even if it's read-only
 		}
 
-		public bool IsPermanentLocation(IOConnectionInfo ioc)
-		{
-			return true;
-		}
-
-		public bool IsReadOnly(IOConnectionInfo ioc)
-		{
-			return false; //TODO implement. note, however, that we MAY return false even if it's read-only
-		}
-
 		public void OnCreate(IFileStorageSetupActivity activity, Bundle savedInstanceState)
 		{
 			_jfs.OnCreate(((IJavaFileStorageFileStorageSetupActivity)activity), savedInstanceState);