#768 Create command for updating messages file

src/main/java/fr/xephi/authme/command/CommandInitializer.java

@@ -11,6 +11,7 @@ import fr.xephi.authme.command.executable.authme.ForceLoginCommand;
 import fr.xephi.authme.command.executable.authme.GetEmailCommand;
 import fr.xephi.authme.command.executable.authme.GetIpCommand;
 import fr.xephi.authme.command.executable.authme.LastLoginCommand;
+import fr.xephi.authme.command.executable.authme.MessagesCommand;
 import fr.xephi.authme.command.executable.authme.PurgeBannedPlayersCommand;
 import fr.xephi.authme.command.executable.authme.PurgeCommand;
 import fr.xephi.authme.command.executable.authme.PurgeLastPositionCommand;
@@ -288,6 +289,15 @@ public class CommandInitializer {
             .executableCommand(ConverterCommand.class)
             .build();
 
+        CommandDescription.builder()
+            .parent(AUTHME_BASE)
+            .labels("messages")
+            .description("Add missing messages")
+            .detailedDescription("Adds missing messages to the current messages file.")
+            // TODO #768: add permission for command
+            .executableCommand(MessagesCommand.class)
+            .build();
+
         // Register the base login command
         final CommandDescription LOGIN_BASE = CommandDescription.builder()
             .parent(null)

src/main/java/fr/xephi/authme/command/executable/authme/MessagesCommand.java

@@ -0,0 +1,48 @@
+package fr.xephi.authme.command.executable.authme;
+
+import fr.xephi.authme.ConsoleLogger;
+import fr.xephi.authme.command.ExecutableCommand;
+import fr.xephi.authme.initialization.DataFolder;
+import fr.xephi.authme.service.MessageUpdater;
+import fr.xephi.authme.settings.Settings;
+import fr.xephi.authme.settings.properties.PluginSettings;
+import org.bukkit.command.CommandSender;
+
+import javax.inject.Inject;
+import java.io.File;
+import java.util.List;
+
+/**
+ * Messages command, updates the user's messages file with any missing files
+ * from the provided file in the JAR.
+ */
+public class MessagesCommand implements ExecutableCommand {
+
+    private static final String DEFAULT_LANGUAGE = "en";
+
+    @Inject
+    private Settings settings;
+    @Inject
+    @DataFolder
+    private File dataFolder;
+
+    @Override
+    public void executeCommand(CommandSender sender, List<String> arguments) {
+        final String language = settings.getProperty(PluginSettings.MESSAGES_LANGUAGE);
+
+        try {
+            new MessageUpdater(
+                new File(dataFolder, getMessagePath(language)),
+                getMessagePath(language),
+                getMessagePath(DEFAULT_LANGUAGE))
+            .executeCopy(sender);
+        } catch (Exception e) {
+            sender.sendMessage("Could not update messages: " + e.getMessage());
+            ConsoleLogger.logException("Could not update messages:", e);
+        }
+    }
+
+    private static String getMessagePath(String code) {
+        return "messages/messages_" + code + ".yml";
+    }
+}