Verify database version before importing

app/src/main/java/org/isoron/uhabits/HabitsApplication.java

@@ -21,10 +21,10 @@ package org.isoron.uhabits;
 
 import android.app.*;
 import android.content.*;
-import android.support.annotation.*;
 
 import com.activeandroid.*;
 
+import org.isoron.uhabits.models.sqlite.*;
 import org.isoron.uhabits.notifications.*;
 import org.isoron.uhabits.preferences.*;
 import org.isoron.uhabits.tasks.*;
@@ -88,7 +88,16 @@ public class HabitsApplication extends Application
             if (db.exists()) db.delete();
         }
 
+        try
+        {
             DatabaseUtils.initializeActiveAndroid(context);
+        }
+        catch (InvalidDatabaseVersionException e)
+        {
+            File db = DatabaseUtils.getDatabaseFile(context);
+            db.renameTo(new File(db.getAbsolutePath() + ".invalid"));
+            DatabaseUtils.initializeActiveAndroid(context);
+        }
 
         widgetUpdater = component.getWidgetUpdater();
         widgetUpdater.startListening();

app/src/main/java/org/isoron/uhabits/io/LoopDBImporter.java

@@ -19,20 +19,20 @@
 
 package org.isoron.uhabits.io;
 
-import android.content.Context;
+import android.content.*;
-import android.database.Cursor;
+import android.database.*;
-import android.database.sqlite.SQLiteDatabase;
+import android.database.sqlite.*;
-import android.support.annotation.NonNull;
+import android.support.annotation.*;
+import android.util.*;
 
-import com.activeandroid.ActiveAndroid;
+import com.activeandroid.*;
 
-import org.isoron.uhabits.AppContext;
+import org.isoron.uhabits.*;
 import org.isoron.uhabits.models.*;
 import org.isoron.uhabits.utils.DatabaseUtils;
-import org.isoron.uhabits.utils.FileUtils;
+import org.isoron.uhabits.utils.*;
 
-import java.io.File;
+import java.io.*;
-import java.io.IOException;
 
 import javax.inject.*;
 
@@ -45,7 +45,8 @@ public class LoopDBImporter extends AbstractImporter
     private Context context;
 
     @Inject
-    public LoopDBImporter(@NonNull @AppContext Context context, @NonNull HabitList habits)
+    public LoopDBImporter(@NonNull @AppContext Context context,
+                          @NonNull HabitList habits)
     {
         super(habits);
         this.context = context;
@@ -59,15 +60,29 @@ public class LoopDBImporter extends AbstractImporter
         SQLiteDatabase db = SQLiteDatabase.openDatabase(file.getPath(), null,
             SQLiteDatabase.OPEN_READONLY);
 
+        boolean canHandle = true;
+
         Cursor c = db.rawQuery(
             "select count(*) from SQLITE_MASTER where name=? or name=?",
             new String[]{ "Checkmarks", "Repetitions" });
 
-        boolean result = (c.moveToFirst() && c.getInt(0) == 2);
+        if (!c.moveToFirst() || c.getInt(0) != 2)
+        {
+            Log.w("LoopDBImporter", "Cannot handle file: tables not found");
+            canHandle = false;
+        }
+
+        if (db.getVersion() > BuildConfig.databaseVersion)
+        {
+            Log.w("LoopDBImporter", String.format(
+                "Cannot handle file: incompatible version: %d > %d",
+                db.getVersion(), BuildConfig.databaseVersion));
+            canHandle = false;
+        }
 
         c.close();
         db.close();
-        return result;
+        return canHandle;
     }
 
     @Override

app/src/main/java/org/isoron/uhabits/models/sqlite/InvalidDatabaseVersionException.java

@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2016 Álinson Santos Xavier <isoron@gmail.com>
+ *
+ * This file is part of Loop Habit Tracker.
+ *
+ * Loop Habit Tracker is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ *
+ * Loop Habit Tracker is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.isoron.uhabits.models.sqlite;
+
+public class InvalidDatabaseVersionException extends RuntimeException
+{
+}

app/src/main/java/org/isoron/uhabits/utils/DatabaseUtils.java

@@ -25,6 +25,7 @@ import android.support.annotation.*;
 import com.activeandroid.*;
 
 import org.isoron.uhabits.*;
+import org.isoron.uhabits.models.sqlite.*;
 import org.isoron.uhabits.models.sqlite.records.*;
 
 import java.io.*;
@@ -76,8 +77,17 @@ public abstract class DatabaseUtils
                 RepetitionRecord.class, ScoreRecord.class, StreakRecord.class)
             .create();
 
+        try
+        {
             ActiveAndroid.initialize(dbConfig);
         }
+        catch (RuntimeException e)
+        {
+            if(e.getMessage().contains("downgrade"))
+                throw new InvalidDatabaseVersionException();
+            else throw e;
+        }
+    }
 
     @SuppressWarnings("ResultOfMethodCallIgnored")
     public static String saveDatabaseCopy(Context context, File dir) throws IOException