Allow selecting any open database in unlock dialog

When showing the database unlock dialog from browser or auto-type and
there's more than one open database, replace the filename label with
a drop-down box of all available files. Switching the filename here will
change the active tab of the main window and unlock it.

This implements the major feature desired by [1] and the noticeable UX
regression between 2.5 and 2.6 when working with multiple databases on
an auto-lock timer.

Notes:
  * Make the DatabaseOpenDialog window ApplicationModal so that it
    blocks input to the main UI when open. This avoids a number of
    corner cases that would otherwise pop up if opening/closing or
    locking/unlocking extra database tabs in the background.
  * This does not handle auto-type/browser scenarios where the active
    database is unlocked but has no matching credentials, and there's
    other locked databases open which the user could be prompted to
    unlock ("Case 2" in the issue).

[1] #2322

src/gui/DatabaseOpenDialog.cpp

@@ -17,6 +17,7 @@
 
 #include "DatabaseOpenDialog.h"
 #include "DatabaseOpenWidget.h"
+#include "DatabaseTabWidget.h"
 #include "DatabaseWidget.h"
 #include "core/Database.h"
 
@@ -26,6 +27,7 @@ DatabaseOpenDialog::DatabaseOpenDialog(QWidget* parent)
 {
     setWindowTitle(tr("Unlock Database - KeePassXC"));
     setWindowFlags(Qt::Dialog | Qt::WindowStaysOnTopHint);
+    setWindowModality(Qt::ApplicationModal);
     connect(m_view, SIGNAL(dialogFinished(bool)), this, SLOT(complete(bool)));
     auto* layout = new QVBoxLayout();
     layout->setMargin(0);
@@ -39,6 +41,42 @@ void DatabaseOpenDialog::setFilePath(const QString& filePath)
     m_view->load(filePath);
 }
 
+/**
+ * This method toggles multi-file mode on the open dialog. In multi-file mode, the database path is
+ * presented as a drop-down list of all open locked databases in the parent DatabaseTabWidget (if
+ * there is more than one).
+ *
+ * Changing the selected database in the drop-down list will change the active tab in the main UI,
+ * so that browser and auto-type searches the current/active database appropriately.
+ *
+ * This method should be called *before* setFilePath. setMultiFile on its own doesn't reload the
+ * child DatabaseOpenWidget view.
+ *
+ * @param multiFile Whether to enable/disable multiFile mode (default is disabled)
+ */
+void DatabaseOpenDialog::setMultiFile(bool multiFile)
+{
+    if (multiFile) {
+        auto* tabWidget = qobject_cast<const DatabaseTabWidget*>(parentWidget());
+        if (!tabWidget) {
+            qWarning("DatabaseOpenDialog::setMultiFile: parent widget is unset or invalid");
+            m_view->clearMultiFileList();
+            return;
+        }
+        QStringList fileList;
+        for (int i = 0, c = tabWidget->count(); i < c; ++i) {
+            auto* dbWidget = tabWidget->databaseWidgetFromIndex(i);
+            Q_ASSERT(dbWidget);
+            if (dbWidget && dbWidget->isLocked()) {
+                fileList << dbWidget->database()->filePath();
+            }
+        }
+        m_view->setMultiFileList(fileList);
+    } else {
+        m_view->clearMultiFileList();
+    }
+}
+
 /**
  * Set target DatabaseWidget to which signals are connected.
  *
@@ -92,3 +130,24 @@ void DatabaseOpenDialog::complete(bool accepted)
     emit dialogFinished(accepted, m_dbWidget);
     clearForms();
 }
+
+void DatabaseOpenDialog::changeFile(const QString& filePath)
+{
+    auto* tabWidget = qobject_cast<DatabaseTabWidget*>(parentWidget());
+    if (!tabWidget) {
+        qWarning("DatabaseOpenDialog::changeFile: parent widget is unset or invalid");
+        return;
+    }
+
+    auto* dbWidget = tabWidget->databaseWidgetFromFilePath(filePath);
+    if (dbWidget) {
+        setTargetDatabaseWidget(dbWidget);
+        // make the newly-selected database active in the UI
+        tabWidget->setCurrentIndex(tabWidget->indexOf(dbWidget));
+        setFilePath(filePath);
+    } else {
+        // no matching dbWidget for the filePath, it probably got closed while this dialog was open.
+        // Cancel and let the user start over.
+        complete(false);
+    }
+}

src/gui/DatabaseOpenDialog.h

@@ -43,6 +43,7 @@ class DatabaseOpenDialog : public QDialog
 
     explicit DatabaseOpenDialog(QWidget* parent = nullptr);
     void setFilePath(const QString& filePath);
+    void setMultiFile(bool multiFile);
     void setTargetDatabaseWidget(DatabaseWidget* dbWidget);
     void setIntent(Intent intent);
     Intent intent() const;
@@ -54,6 +55,7 @@ class DatabaseOpenDialog : public QDialog
 
 public slots:
     void complete(bool accepted);
+    void changeFile(const QString& filePath);
 
 private:
     QPointer<DatabaseOpenWidget> m_view;

src/gui/DatabaseOpenWidget.cpp

@@ -24,6 +24,7 @@
 #include "core/Resources.h"
 #include "crypto/Random.h"
 #include "format/KeePass2Reader.h"
+#include "gui/DatabaseOpenDialog.h"
 #include "gui/FileDialog.h"
 #include "gui/MainWindow.h"
 #include "gui/MessageBox.h"
@@ -143,9 +144,30 @@ void DatabaseOpenWidget::load(const QString& filename)
     clearForms();
 
     m_filename = filename;
-    m_ui->fileNameLabel->setRawText(m_filename);
+
+    if (m_multiFileList.count() > 1) {
+        m_ui->fileNameLabel->setVisible(false);
+        m_ui->fileNameList->addItems(m_multiFileList);
+        m_ui->fileNameList->setCurrentText(filename);
+        m_ui->fileNameList->setVisible(true);
+
+        // changing the file in a dropdown needs to go back up the parent tree to change the current database tab.
+        // The handler of this signal will come back and call load() here again.
+        auto* parentDialog = qobject_cast<DatabaseOpenDialog*>(parentWidget());
+        if (parentDialog) {
+            // clang-format off
+            connect(m_ui->fileNameList, SIGNAL(textActivated(const QString&)),
+                    parentDialog, SLOT(changeFile(const QString&)));
+            // clang-format on
+        }
+    } else {
+        m_ui->fileNameLabel->setRawText(m_filename);
+        m_ui->fileNameLabel->setVisible(true);
+        m_ui->fileNameList->setVisible(false);
+    }
 
     m_ui->keyFileClearIcon->setVisible(false);
+    m_ui->editPassword->setFocus();
 
     if (config()->get(Config::RememberLastKeyFiles).toBool()) {
         auto lastKeyFiles = config()->get(Config::LastKeyFiles).toHash();
@@ -168,8 +190,24 @@ void DatabaseOpenWidget::load(const QString& filename)
 #endif
 }
 
+/**
+ * Set a list of files in a drop-down to choose a different database.
+ * Must be called before load(), and should only be called by DatabaseOpenDialog
+ */
+void DatabaseOpenWidget::setMultiFileList(const QStringList& filenameList)
+{
+    m_multiFileList = filenameList;
+}
+
+void DatabaseOpenWidget::clearMultiFileList()
+{
+    m_multiFileList.clear();
+}
+
 void DatabaseOpenWidget::clearForms()
 {
+    disconnect(m_ui->fileNameList, SIGNAL(textActivated(const QString&)), nullptr, nullptr);
+    m_ui->fileNameList->clear();
     m_ui->editPassword->setText("");
     m_ui->editPassword->setShowPassword(false);
     m_ui->keyFileLineEdit->clear();
@@ -183,7 +221,7 @@ QSharedPointer<Database> DatabaseOpenWidget::database()
     return m_db;
 }
 
-QString DatabaseOpenWidget::filename()
+QString DatabaseOpenWidget::filename() const
 {
     return m_filename;
 }

src/gui/DatabaseOpenWidget.h

@@ -41,7 +41,9 @@ class DatabaseOpenWidget : public DialogyWidget
     explicit DatabaseOpenWidget(QWidget* parent = nullptr);
     ~DatabaseOpenWidget();
     void load(const QString& filename);
-    QString filename();
+    void setMultiFileList(const QStringList& filenameList);
+    void clearMultiFileList();
+    QString filename() const;
     void clearForms();
     void enterKey(const QString& pw, const QString& keyFile);
     QSharedPointer<Database> database();
@@ -57,6 +59,7 @@ class DatabaseOpenWidget : public DialogyWidget
     const QScopedPointer<Ui::DatabaseOpenWidget> m_ui;
     QSharedPointer<Database> m_db;
     QString m_filename;
+    QStringList m_multiFileList;
     bool m_retryUnlockWithEmptyPassword = false;
 
 protected slots:

src/gui/DatabaseOpenWidget.ui

@@ -90,6 +90,13 @@
           </property>
          </widget>
         </item>
+        <item>
+         <widget class="QComboBox" name="fileNameList">
+          <property name="visible">
+           <bool>false</bool>
+          </property>
+         </widget>
+        </item>
         <item>
          <spacer name="verticalSpacer_3">
           <property name="orientation">

src/gui/DatabaseTabWidget.cpp

@@ -619,6 +619,18 @@ DatabaseWidget* DatabaseTabWidget::currentDatabaseWidget()
     return qobject_cast<DatabaseWidget*>(currentWidget());
 }
 
+DatabaseWidget* DatabaseTabWidget::databaseWidgetFromFilePath(const QString& filePath) const
+{
+    for (int i = 0, c = count(); i < c; ++i) {
+        auto* dbWidget = databaseWidgetFromIndex(i);
+        Q_ASSERT(dbWidget);
+        if (dbWidget && (dbWidget->database()->filePath() == filePath)) {
+            return dbWidget;
+        }
+    }
+    return nullptr;
+}
+
 /**
  * Attempt to lock all open databases
  *
@@ -666,6 +678,8 @@ void DatabaseTabWidget::unlockDatabaseInDialog(DatabaseWidget* dbWidget,
 {
     m_databaseOpenDialog->setTargetDatabaseWidget(dbWidget);
     m_databaseOpenDialog->setIntent(intent);
+    m_databaseOpenDialog->setMultiFile(intent == DatabaseOpenDialog::Intent::AutoType
+                                       || intent == DatabaseOpenDialog::Intent::Browser);
     m_databaseOpenDialog->setFilePath(filePath);
 
 #ifdef Q_OS_MACOS

src/gui/DatabaseTabWidget.h

@@ -41,6 +41,7 @@ class DatabaseTabWidget : public QTabWidget
     QString tabName(int index);
     DatabaseWidget* currentDatabaseWidget();
     DatabaseWidget* databaseWidgetFromIndex(int index) const;
+    DatabaseWidget* databaseWidgetFromFilePath(const QString& filePath) const;
 
     bool isReadOnly(int index = -1) const;
     bool canSave(int index = -1) const;