From 2669fb00f16eb96f73c87bcc10c318a54ede782d Mon Sep 17 00:00:00 2001
From: Radek Davidek <rdavidek@trask.cz>
Date: Wed, 29 Apr 2026 19:11:57 +0200
Subject: [PATCH] added feature for changing master password

Co-authored-by: Copilot <copilot@github.com>
---
 .../java/cz/kamma/jkeepass/KeepassApp.java    | 71 ++++++++++++++++++-
 1 file changed, 70 insertions(+), 1 deletion(-)

diff --git a/src/main/java/cz/kamma/jkeepass/KeepassApp.java b/src/main/java/cz/kamma/jkeepass/KeepassApp.java
index e18d335..76592a8 100644
--- a/src/main/java/cz/kamma/jkeepass/KeepassApp.java
+++ b/src/main/java/cz/kamma/jkeepass/KeepassApp.java
@@ -87,6 +87,7 @@ public class KeepassApp extends JFrame {
     
     // Menu items that need state management
     private JMenuItem menuSave;
+    private JMenuItem menuChangeMasterPassword;
     private JMenuItem menuLock;
     private JMenuItem menuEntryAdd;
     private JMenuItem menuEntryEdit;
@@ -171,12 +172,14 @@ public class KeepassApp extends JFrame {
         JMenuItem openItem = new JMenuItem("Open Database...");
         recentMenu = new JMenu("Open Recent");
         menuSave = new JMenuItem("Save");
+        menuChangeMasterPassword = new JMenuItem("Change Master Password...");
         JMenuItem minimizeItem = new JMenuItem("Minimize & Lock");
         menuLock = new JMenuItem("Lock Database");
         JMenuItem exitItem = new JMenuItem("Exit");
 
         openItem.addActionListener(e -> openDatabase(null));
         menuSave.addActionListener(e -> saveDatabase());
+        menuChangeMasterPassword.addActionListener(e -> changeMasterPassword());
         minimizeItem.addActionListener(e -> minimizeToCustomTray());
         menuLock.addActionListener(e -> lockDatabase());
         exitItem.addActionListener(e -> System.exit(0));
@@ -184,6 +187,7 @@ public class KeepassApp extends JFrame {
         fileMenu.add(openItem);
         fileMenu.add(recentMenu);
         fileMenu.add(menuSave);
+        fileMenu.add(menuChangeMasterPassword);
         fileMenu.addSeparator();
         fileMenu.add(menuLock);
         fileMenu.add(minimizeItem);
@@ -449,7 +453,7 @@ public class KeepassApp extends JFrame {
      */
     private void updateMenuState() {
         // Safely check if menu items are initialized (they might not be during early init)
-        if (menuSave == null || menuLock == null || menuEntryAdd == null || 
+        if (menuSave == null || menuChangeMasterPassword == null || menuLock == null || menuEntryAdd == null || 
             menuEntryEdit == null || menuEntryDelete == null || 
             menuEditCopyUser == null || menuEditCopyPass == null) {
             return;
@@ -461,6 +465,7 @@ public class KeepassApp extends JFrame {
         
         // File menu items
         menuSave.setEnabled(dbIsLoaded);
+        menuChangeMasterPassword.setEnabled(dbIsLoaded);
         menuLock.setEnabled(dbIsLoaded);
         
         // Entry menu items
@@ -594,6 +599,70 @@ public class KeepassApp extends JFrame {
         }
     }
 
+    private void changeMasterPassword() {
+        if (database == null || currentFile == null || currentPassword == null) {
+            JOptionPane.showMessageDialog(this, "Database must be unlocked to change master password.", "Warning", JOptionPane.WARNING_MESSAGE);
+            return;
+        }
+
+        JPasswordField newPasswordField = new JPasswordField(24);
+        JPasswordField confirmPasswordField = new JPasswordField(24);
+        Dimension passwordFieldSize = new Dimension(260, newPasswordField.getPreferredSize().height);
+        newPasswordField.setPreferredSize(passwordFieldSize);
+        confirmPasswordField.setPreferredSize(passwordFieldSize);
+
+        JPanel panel = new JPanel(new GridBagLayout());
+        GridBagConstraints gbc = new GridBagConstraints();
+        gbc.insets = new Insets(5, 5, 5, 5);
+        gbc.anchor = GridBagConstraints.WEST;
+        gbc.fill = GridBagConstraints.HORIZONTAL;
+        gbc.gridx = 0;
+        gbc.gridy = 0;
+        panel.add(new JLabel("New master password:"), gbc);
+        gbc.gridx = 1;
+        panel.add(newPasswordField, gbc);
+
+        gbc.gridx = 0;
+        gbc.gridy = 1;
+        panel.add(new JLabel("Confirm password:"), gbc);
+        gbc.gridx = 1;
+        panel.add(confirmPasswordField, gbc);
+
+        int result = JOptionPane.showConfirmDialog(
+                this,
+                panel,
+                "Change Master Password",
+                JOptionPane.OK_CANCEL_OPTION,
+                JOptionPane.PLAIN_MESSAGE
+        );
+
+        if (result != JOptionPane.OK_OPTION) {
+            return;
+        }
+
+        String newPassword = new String(newPasswordField.getPassword());
+        String confirmPassword = new String(confirmPasswordField.getPassword());
+
+        if (newPassword.isEmpty()) {
+            JOptionPane.showMessageDialog(this, "Master password cannot be empty.", "Warning", JOptionPane.WARNING_MESSAGE);
+            return;
+        }
+
+        if (!newPassword.equals(confirmPassword)) {
+            JOptionPane.showMessageDialog(this, "Passwords do not match.", "Warning", JOptionPane.WARNING_MESSAGE);
+            return;
+        }
+
+        try {
+            CustomDatabaseFormat.saveDatabase(currentFile, database, newPassword);
+            currentPassword = newPassword;
+            statusLabel.setText(" Master password changed successfully.");
+        } catch (Exception ex) {
+            JOptionPane.showMessageDialog(this, "Error changing master password: " + ex.getMessage(), "Error", JOptionPane.ERROR_MESSAGE);
+            ex.printStackTrace();
+        }
+    }
+
     private void lockDatabase() {
         if (database == null) return;