[Client] Warn when data paths point inside the program directory (#7473)

Co-authored-by: Lukas Brübach <Bruebach.Lukas@bdosecurity.de>

cockatrice/src/interface/widgets/dialogs/path_safety_warning.cpp

@@ -0,0 +1,34 @@
+#include "path_safety_warning.h"
+
+#include "../../client/settings/cache_settings.h"
+
+#include <QCoreApplication>
+#include <QMessageBox>
+#include <QObject>
+#include <QString>
+#include <libcockatrice/settings/paths_settings.h>
+
+class QWidget;
+
+bool PathSafetyWarning::confirmOutsideProgramDir(QWidget *parent, const QString &path)
+{
+    if (SettingsCache::instance().getIsPortableBuild()) {
+        return true;
+    }
+
+    if (!PathsSettings::isInsideDir(path, QCoreApplication::applicationDirPath())) {
+        return true;
+    }
+
+    QMessageBox box(QMessageBox::Warning, QObject::tr("Path inside the program directory"),
+                    QObject::tr("'%1' is inside the Cockatrice program directory.\n\n"
+                                "Files stored there can be deleted by an update or by uninstalling "
+                                "Cockatrice, so this change was not applied. Choose a location outside "
+                                "the program directory.")
+                        .arg(path),
+                    QMessageBox::Ok, parent);
+    box.setTextFormat(Qt::PlainText);
+    box.exec();
+
+    return false;
+}

cockatrice/src/interface/widgets/dialogs/path_safety_warning.h

@@ -0,0 +1,25 @@
+#ifndef COCKATRICE_PATH_SAFETY_WARNING_H
+#define COCKATRICE_PATH_SAFETY_WARNING_H
+
+class QString;
+class QWidget;
+
+namespace PathSafetyWarning
+{
+
+/**
+ * @brief Warns when the user tries to configure a data path inside the program directory.
+ *
+ * Shows a message box explaining that files kept there can be deleted by an
+ * update or by uninstalling Cockatrice. Portable builds are always exempt:
+ * their data lives beside the executables by design.
+ *
+ * @param parent The parent widget
+ * @param path The path the user is trying to configure
+ * @return true when the path is outside the program directory and safe to apply
+ */
+bool confirmOutsideProgramDir(QWidget *parent, const QString &path);
+
+} // namespace PathSafetyWarning
+
+#endif // COCKATRICE_PATH_SAFETY_WARNING_H