#457 Improve ForceFlatToSqlite conversion

- Change ForceFlatToSqlite converter to use a generic datasource destination (i.e. can be used for Flat2MySQL later)
- Add tests, including for FlatFile
- Check that user is not present in destination datasource before adding
- Persist last location from flatfile as well

src/main/java/fr/xephi/authme/converter/ForceFlatToSqlite.java

@@ -3,39 +3,51 @@ package fr.xephi.authme.converter;
 import fr.xephi.authme.ConsoleLogger;
 import fr.xephi.authme.cache.auth.PlayerAuth;
 import fr.xephi.authme.datasource.DataSource;
-import fr.xephi.authme.datasource.DataSourceType;
-import fr.xephi.authme.datasource.SQLite;
-import fr.xephi.authme.settings.NewSetting;
-import fr.xephi.authme.settings.properties.DatabaseSettings;
-import java.sql.SQLException;
+import fr.xephi.authme.datasource.FlatFile;
+import fr.xephi.authme.util.StringUtils;
+
+import java.util.ArrayList;
+import java.util.List;
 
 /**
  * Mandatory migration from the deprecated flat file datasource to SQLite.
  */
-public class ForceFlatToSqlite {
+public class ForceFlatToSqlite implements Converter {
 
-    private final DataSource database;
-    private final NewSetting settings;
+    private final DataSource source;
+    private final DataSource destination;
 
-    public ForceFlatToSqlite(DataSource database, NewSetting settings) {
-        this.database = database;
-        this.settings = settings;
+    /**
+     * Constructor.
+     *
+     * @param source The datasource to convert (flatfile)
+     * @param destination The datasource to copy the data to (sqlite)
+     */
+    public ForceFlatToSqlite(FlatFile source, DataSource destination) {
+        this.source = source;
+        this.destination = destination;
     }
 
-    public DataSource run() {
-        try {
-            DataSource sqlite = new SQLite(settings);
-            for (PlayerAuth auth : database.getAllAuths()) {
-                auth.setRealName("Player");
-                sqlite.saveAuth(auth);
+    /**
+     * Perform the conversion.
+     */
+    @Override
+    public void run() {
+        List<String> skippedPlayers = new ArrayList<>();
+        for (PlayerAuth auth : source.getAllAuths()) {
+            if (destination.isAuthAvailable(auth.getNickname())) {
+                skippedPlayers.add(auth.getNickname());
+            } else {
+                destination.saveAuth(auth);
+                destination.updateQuitLoc(auth);
             }
-            settings.setProperty(DatabaseSettings.BACKEND, DataSourceType.SQLITE);
-            settings.save();
-            ConsoleLogger.info("Database successfully converted to sqlite!");
-            return sqlite;
-        } catch (SQLException | ClassNotFoundException e) {
-            ConsoleLogger.logException("Could not convert from Flatfile to SQLite:", e);
         }
-        return null;
+
+        if (!skippedPlayers.isEmpty()) {
+            ConsoleLogger.showError("Warning: skipped conversion for players which were already in SQLite: "
+                + StringUtils.join(", ", skippedPlayers));
+        }
+        ConsoleLogger.info("Database successfully converted from " + source.getClass().getSimpleName()
+            + " to " + destination.getClass().getSimpleName());
     }
 }