Detect background changes to database file.

This gives the option to reload the database.

TODO:
 - Settings for reloadBehavior (ask, reloadUnchanged, ignore)
 - Improve notification, by using a header instead of dialog: nicer, less
intrusive, gives more options to user, and works better when multiple databases
are open.
 - Keep tab order on reload.

src/core/Database.cpp

@@ -227,6 +227,11 @@ bool Database::verifyKey(const CompositeKey& key) const
     return (m_key.rawKey() == key.rawKey());
 }
 
+CompositeKey Database::key() const
+{
+    return m_key;
+}
+
 void Database::createRecycleBin()
 {
     Group* recycleBin = Group::createRecycleBin();

src/core/Database.h

@@ -88,6 +88,7 @@ public:
     void setKey(const CompositeKey& key);
     bool hasKey() const;
     bool verifyKey(const CompositeKey& key) const;
+    CompositeKey key() const;
     void recycleEntry(Entry* entry);
     void recycleGroup(Group* group);
     void setEmitModified(bool value);

src/gui/DatabaseOpenWidget.cpp

@@ -91,14 +91,26 @@ void DatabaseOpenWidget::enterKey(const QString& pw, const QString& keyFile)
     openDatabase();
 }
 
+void DatabaseOpenWidget::enterKey(const CompositeKey& masterKey)
+{
+    if (masterKey.isEmpty()) {
+        return;
+    }
+    openDatabase(masterKey);
+}
+
 void DatabaseOpenWidget::openDatabase()
 {
-    KeePass2Reader reader;
     CompositeKey masterKey = databaseKey();
     if (masterKey.isEmpty()) {
         return;
     }
+    openDatabase(masterKey);
+}
 
+void DatabaseOpenWidget::openDatabase(const CompositeKey& masterKey)
+{
+    KeePass2Reader reader;
     QFile file(m_filename);
     if (!file.open(QIODevice::ReadOnly)) {
         // TODO: error message

src/gui/DatabaseOpenWidget.h

@@ -39,6 +39,7 @@ public:
     ~DatabaseOpenWidget();
     void load(const QString& filename);
     void enterKey(const QString& pw, const QString& keyFile);
+    void enterKey(const CompositeKey& masterKey);
     Database* database();
 
 Q_SIGNALS:
@@ -49,6 +50,7 @@ protected:
 
 protected Q_SLOTS:
     virtual void openDatabase();
+    void openDatabase(const CompositeKey& masterKey);
     void reject();
 
 private Q_SLOTS:

src/gui/DatabaseTabWidget.cpp

@@ -20,6 +20,9 @@
 #include <QtCore/QFileInfo>
 #include <QtGui/QTabWidget>
 #include <QtGui/QMessageBox>
+#include <QtCore/QFileSystemWatcher>
+#include <QtCore/QTimer>
+#include <QtCore/QDebug>
 
 #include "autotype/AutoType.h"
 #include "core/Config.h"
@@ -45,7 +48,9 @@ DatabaseManagerStruct::DatabaseManagerStruct()
 const int DatabaseTabWidget::LastDatabasesCount = 5;
 
 DatabaseTabWidget::DatabaseTabWidget(QWidget* parent)
-    : QTabWidget(parent)
+    : QTabWidget(parent),
+      m_fileWatcher(new QFileSystemWatcher(this)),
+      m_reloadBehavior(ReloadUnmodified)    //TODO: setting
 {
     DragTabBar* tabBar = new DragTabBar(this);
     tabBar->setDrawBase(false);
@@ -53,6 +58,7 @@ DatabaseTabWidget::DatabaseTabWidget(QWidget* parent)
 
     connect(this, SIGNAL(tabCloseRequested(int)), SLOT(closeDatabase(int)));
     connect(autoType(), SIGNAL(globalShortcutTriggered()), SLOT(performGlobalAutoType()));
+    connect(m_fileWatcher, SIGNAL(fileChanged(QString)), SLOT(fileChanged(QString)));
 }
 
 DatabaseTabWidget::~DatabaseTabWidget()
@@ -92,7 +98,7 @@ void DatabaseTabWidget::openDatabase()
 }
 
 void DatabaseTabWidget::openDatabase(const QString& fileName, const QString& pw,
-                                     const QString& keyFile)
+                                     const QString& keyFile, const CompositeKey& key)
 {
     QFileInfo fileInfo(fileName);
     QString canonicalFilePath = fileInfo.canonicalFilePath();
@@ -136,12 +142,17 @@ void DatabaseTabWidget::openDatabase(const QString& fileName, const QString& pw,
     dbStruct.filePath = fileInfo.absoluteFilePath();
     dbStruct.canonicalFilePath = canonicalFilePath;
     dbStruct.fileName = fileInfo.fileName();
+    dbStruct.lastModified = fileInfo.lastModified();
 
     insertDatabase(db, dbStruct);
+    m_fileWatcher->addPath(dbStruct.filePath);
 
     updateRecentDatabases(dbStruct.filePath);
 
-    if (!pw.isNull() || !keyFile.isEmpty()) {
+    if (!key.isEmpty()) {
+        dbStruct.dbWidget->switchToOpenDatabase(dbStruct.filePath, key);
+    }
+    else if (!pw.isNull() || !keyFile.isEmpty()) {
         dbStruct.dbWidget->switchToOpenDatabase(dbStruct.filePath, pw, keyFile);
     }
     else {
@@ -168,6 +179,111 @@ void DatabaseTabWidget::importKeePass1Database()
     dbStruct.dbWidget->switchToImportKeepass1(fileName);
 }
 
+void DatabaseTabWidget::fileChanged(const QString &fileName)
+{
+    const bool wasEmpty = m_changedFiles.isEmpty();
+    m_changedFiles.insert(fileName);
+    if (wasEmpty && !m_changedFiles.isEmpty())
+        QTimer::singleShot(200, this, SLOT(checkReloadDatabases()));
+}
+
+void DatabaseTabWidget::expectFileChange(const DatabaseManagerStruct& dbStruct)
+{
+    if (dbStruct.filePath.isEmpty())
+        return;
+    m_expectedFileChanges.insert(dbStruct.filePath);
+}
+
+void DatabaseTabWidget::unexpectFileChange(DatabaseManagerStruct& dbStruct)
+{
+    if (dbStruct.filePath.isEmpty())
+        return;
+    m_expectedFileChanges.remove(dbStruct.filePath);
+    dbStruct.lastModified = QFileInfo(dbStruct.filePath).lastModified();
+}
+
+void DatabaseTabWidget::checkReloadDatabases()
+{
+    QSet<QString> changedFiles;
+
+    changedFiles = m_changedFiles.subtract(m_expectedFileChanges);
+    m_changedFiles.clear();
+
+    if (changedFiles.isEmpty())
+        return;
+
+    Q_FOREACH (DatabaseManagerStruct dbStruct, m_dbList) {
+        QString filePath = dbStruct.filePath;
+        Database * db = dbStruct.dbWidget->database();
+
+        if (!changedFiles.contains(filePath))
+            continue;
+
+        QFileInfo fi(filePath);
+        QDateTime lastModified = fi.lastModified();
+        if (dbStruct.lastModified == lastModified)
+            continue;
+
+        DatabaseWidget::Mode mode = dbStruct.dbWidget->currentMode();
+        if (mode == DatabaseWidget::None || mode == DatabaseWidget::LockedMode || !db->hasKey())
+            continue;
+
+        if (   (m_reloadBehavior == AlwaysAsk)
+            || (m_reloadBehavior == ReloadUnmodified && mode == DatabaseWidget::EditMode)
+            || (m_reloadBehavior == ReloadUnmodified && dbStruct.modified)) {
+            //TODO: display banner instead, to let user now file has changed and choose to Reload, Overwrite, and SaveAs
+            //      --> less obstrubsive (esp. if multiple DB are open), cleaner UI
+            if (QMessageBox::warning(this, fi.exists() ? tr("Database file changed") : tr("Database file removed"),
+                                     tr("Do you want to discard your changes and reload?"),
+                                     QMessageBox::Yes|QMessageBox::No) == QMessageBox::No)
+                continue;
+        }
+
+        if (fi.exists()) {
+            //Ignore/cancel all edits
+            dbStruct.dbWidget->switchToView(false);
+            dbStruct.modified = false;
+
+            //Save current group/entry
+            Uuid currentGroup;
+            if (Group* group = dbStruct.dbWidget->groupView()->currentGroup())
+                currentGroup = group->uuid();
+            Uuid currentEntry;
+            if (Entry* entry = dbStruct.dbWidget->entryView()->currentEntry())
+                currentEntry = entry->uuid();
+            QString searchText = dbStruct.dbWidget->searchText();
+
+            //Reload updated db
+            CompositeKey key = db->key();
+            closeDatabase(db);
+            openDatabase(filePath, QString(), QString(), key);
+
+            //Restore current group/entry
+            dbStruct = indexDatabaseManagerStruct(count() - 1);
+            if (dbStruct.dbWidget) {
+                Database * db = dbStruct.dbWidget->database();
+                if (!searchText.isEmpty())
+                    dbStruct.dbWidget->showSearch(searchText);
+                if (!currentGroup.isNull())
+                    if (Group* group = db->resolveGroup(currentGroup))
+                        dbStruct.dbWidget->groupView()->setCurrentGroup(group);
+                if (!currentEntry.isNull())
+                    if (Entry* entry = db->resolveEntry(currentEntry))
+                        dbStruct.dbWidget->entryView()->setCurrentEntry(entry);
+            }
+
+            //TODO: keep tab order...
+        } else {
+            //Ignore/cancel all edits
+            dbStruct.dbWidget->switchToView(false);
+            dbStruct.modified = false;
+
+            //Close database
+            closeDatabase(dbStruct.dbWidget->database());
+        }
+    }
+}
+
 bool DatabaseTabWidget::closeDatabase(Database* db)
 {
     Q_ASSERT(db);
@@ -219,6 +335,7 @@ void DatabaseTabWidget::deleteDatabase(Database* db)
     const DatabaseManagerStruct dbStruct = m_dbList.value(db);
     int index = databaseIndex(db);
 
+    m_fileWatcher->removePath(dbStruct.filePath);
     removeTab(index);
     toggleTabbar();
     m_dbList.remove(db);
@@ -260,12 +377,16 @@ void DatabaseTabWidget::saveDatabase(Database* db)
     if (dbStruct.saveToFilename) {
         bool result = false;
 
+        expectFileChange(dbStruct);
+
         QSaveFile saveFile(dbStruct.filePath);
         if (saveFile.open(QIODevice::WriteOnly)) {
             m_writer.writeDatabase(&saveFile, db);
             result = saveFile.commit();
         }
 
+        unexpectFileChange(dbStruct);
+
         if (result) {
             dbStruct.modified = false;
             updateTabName(db);
@@ -283,12 +404,12 @@ void DatabaseTabWidget::saveDatabase(Database* db)
 void DatabaseTabWidget::saveDatabaseAs(Database* db)
 {
     DatabaseManagerStruct& dbStruct = m_dbList[db];
-    QString oldFileName;
+    QString oldFilePath;
     if (dbStruct.saveToFilename) {
-        oldFileName = dbStruct.filePath;
+        oldFilePath = dbStruct.filePath;
     }
     QString fileName = fileDialog()->getSaveFileName(this, tr("Save database as"),
-                                                     oldFileName, tr("KeePass 2 Database").append(" (*.kdbx)"));
+                                                     oldFilePath, tr("KeePass 2 Database").append(" (*.kdbx)"));
     if (!fileName.isEmpty()) {
         bool result = false;
 
@@ -299,15 +420,18 @@ void DatabaseTabWidget::saveDatabaseAs(Database* db)
         }
 
         if (result) {
+            m_fileWatcher->removePath(oldFilePath);
             dbStruct.modified = false;
             dbStruct.saveToFilename = true;
             QFileInfo fileInfo(fileName);
             dbStruct.filePath = fileInfo.absoluteFilePath();
             dbStruct.canonicalFilePath = fileInfo.canonicalFilePath();
             dbStruct.fileName = fileInfo.fileName();
+            dbStruct.lastModified = fileInfo.lastModified();
             dbStruct.dbWidget->updateFilename(dbStruct.filePath);
             updateTabName(db);
             updateRecentDatabases(dbStruct.filePath);
+            m_fileWatcher->addPath(dbStruct.filePath);
         }
         else {
             QMessageBox::critical(this, tr("Error"), tr("Writing the database failed.") + "\n\n"

src/gui/DatabaseTabWidget.h

@@ -18,7 +18,9 @@
 #ifndef KEEPASSX_DATABASETABWIDGET_H
 #define KEEPASSX_DATABASETABWIDGET_H
 
+#include <QtCore/QDateTime>
 #include <QtCore/QHash>
+#include <QtCore/QSet>
 #include <QtGui/QTabWidget>
 
 #include "format/KeePass2Writer.h"
@@ -27,6 +29,7 @@
 class DatabaseWidget;
 class DatabaseOpenWidget;
 class QFile;
+class QFileSystemWatcher;
 
 struct DatabaseManagerStruct
 {
@@ -39,6 +42,7 @@ struct DatabaseManagerStruct
     bool saveToFilename;
     bool modified;
     bool readOnly;
+    QDateTime lastModified;
 };
 
 Q_DECLARE_TYPEINFO(DatabaseManagerStruct, Q_MOVABLE_TYPE);
@@ -51,16 +55,24 @@ public:
     explicit DatabaseTabWidget(QWidget* parent = Q_NULLPTR);
     ~DatabaseTabWidget();
     void openDatabase(const QString& fileName, const QString& pw = QString(),
-                      const QString& keyFile = QString());
+                      const QString& keyFile = QString(), const CompositeKey& key = CompositeKey());
     DatabaseWidget* currentDatabaseWidget();
     bool hasLockableDatabases();
 
     static const int LastDatabasesCount;
 
+    enum ReloadBehavior {
+        AlwaysAsk,
+        ReloadUnmodified,
+        IgnoreAll
+    };
+
 public Q_SLOTS:
     void newDatabase();
     void openDatabase();
     void importKeePass1Database();
+    void fileChanged(const QString& fileName);
+    void checkReloadDatabases();
     void saveDatabase(int index = -1);
     void saveDatabaseAs(int index = -1);
     bool closeDatabase(int index = -1);
@@ -96,9 +108,15 @@ private:
     void insertDatabase(Database* db, const DatabaseManagerStruct& dbStruct);
     void updateRecentDatabases(const QString& filename);
     void connectDatabase(Database* newDb, Database* oldDb = Q_NULLPTR);
+    void expectFileChange(const DatabaseManagerStruct& dbStruct);
+    void unexpectFileChange(DatabaseManagerStruct& dbStruct);
 
     KeePass2Writer m_writer;
     QHash<Database*, DatabaseManagerStruct> m_dbList;
+    QSet<QString> m_changedFiles;
+    QSet<QString> m_expectedFileChanges;
+    QFileSystemWatcher* m_fileWatcher;
+    ReloadBehavior m_reloadBehavior;
 };
 
 #endif // KEEPASSX_DATABASETABWIDGET_H

src/gui/DatabaseWidget.cpp

@@ -533,6 +533,13 @@ void DatabaseWidget::switchToOpenDatabase(const QString& fileName, const QString
     m_databaseOpenWidget->enterKey(password, keyFile);
 }
 
+void DatabaseWidget::switchToOpenDatabase(const QString &fileName, const CompositeKey& masterKey)
+{
+    updateFilename(fileName);
+    switchToOpenDatabase(fileName);
+    m_databaseOpenWidget->enterKey(masterKey);
+}
+
 void DatabaseWidget::switchToImportKeepass1(const QString& fileName)
 {
     updateFilename(fileName);
@@ -556,10 +563,10 @@ void DatabaseWidget::closeSearch()
     m_groupView->setCurrentGroup(m_lastGroup);
 }
 
-void DatabaseWidget::showSearch()
+void DatabaseWidget::showSearch(const QString & searchString)
 {
     m_searchUi->searchEdit->blockSignals(true);
-    m_searchUi->searchEdit->clear();
+    m_searchUi->searchEdit->setText(searchString);
     m_searchUi->searchEdit->blockSignals(false);
 
     m_searchUi->searchCurrentRadioButton->blockSignals(true);
@@ -665,6 +672,11 @@ bool DatabaseWidget::isInSearchMode()
     return m_entryView->inEntryListMode();
 }
 
+QString DatabaseWidget::searchText()
+{
+    return m_entryView->inEntryListMode() ? m_searchUi->searchEdit->text() : QString();
+}
+
 void DatabaseWidget::clearLastGroup(Group* group)
 {
     if (group) {

src/gui/DatabaseWidget.h

@@ -37,6 +37,7 @@ class KeePass1OpenWidget;
 class QFile;
 class QMenu;
 class UnlockDatabaseWidget;
+class CompositeKey;
 
 namespace Ui {
     class SearchWidget;
@@ -63,6 +64,7 @@ public:
     bool dbHasKey();
     bool canDeleteCurrentGoup();
     bool isInSearchMode();
+    QString searchText();
     int addWidget(QWidget* w);
     void setCurrentIndex(int index);
     void setCurrentWidget(QWidget* widget);
@@ -97,14 +99,16 @@ public Q_SLOTS:
     void switchToDatabaseSettings();
     void switchToOpenDatabase(const QString& fileName);
     void switchToOpenDatabase(const QString& fileName, const QString& password, const QString& keyFile);
+    void switchToOpenDatabase(const QString &fileName, const CompositeKey &masterKey);
     void switchToImportKeepass1(const QString& fileName);
+    void switchToView(bool accepted);
     void toggleSearch();
+    void showSearch(const QString & searchString = QString());
     void emitGroupContextMenuRequested(const QPoint& pos);
     void emitEntryContextMenuRequested(const QPoint& pos);
 
 private Q_SLOTS:
     void switchBackToEntryEdit();
-    void switchToView(bool accepted);
     void switchToHistoryView(Entry* entry);
     void switchToEntryEdit(Entry* entry);
     void switchToEntryEdit(Entry* entry, bool create);
@@ -117,7 +121,6 @@ private Q_SLOTS:
     void search();
     void startSearch();
     void startSearchTimer();
-    void showSearch();
     void closeSearch();
 
 private:

src/gui/MainWindow.cpp

@@ -284,6 +284,15 @@ void MainWindow::clearLastDatabases()
     config()->set("LastDatabases", QVariant());
 }
 
+void MainWindow::changeEvent(QEvent *e)
+{
+    QMainWindow::changeEvent(e);
+    if (e->type() == QEvent::ActivationChange) {
+        if (isActiveWindow())
+            m_ui->tabWidget->checkReloadDatabases();
+    }
+}
+
 void MainWindow::openDatabase(const QString& fileName, const QString& pw, const QString& keyFile)
 {
     m_ui->tabWidget->openDatabase(fileName, pw, keyFile);

src/gui/MainWindow.h

@@ -41,6 +41,7 @@ public Q_SLOTS:
                       const QString& keyFile = QString());
 
 protected:
+    void changeEvent(QEvent *e);
     void closeEvent(QCloseEvent* event) Q_DECL_OVERRIDE;
 
 private Q_SLOTS: