Backup setting on exit to plugin config dir

Only one version of the settings file will be kept per scene collection
and plugin version combination

lib/utils/backup.cpp

@@ -0,0 +1,86 @@
+#include "backup.hpp"
+#include "log-helper.hpp"
+#include "obs-module-helper.hpp"
+#include "path-helpers.hpp"
+#include "plugin-state-helpers.hpp"
+#include "ui-helpers.hpp"
+#include "version.h"
+
+#include <obs-frontend-api.h>
+#include <obs-module.h>
+#include <QFileDialog>
+#include <QTextStream>
+#include <util/config-file.h>
+
+namespace advss {
+
+void AskForBackup(const QString &json)
+{
+	const bool backupWasConfirmed = DisplayMessage(
+		obs_module_text("AdvSceneSwitcher.askBackup"), true, false);
+
+	if (!backupWasConfirmed) {
+		return;
+	}
+
+	QString path = QFileDialog::getSaveFileName(
+		nullptr,
+		obs_module_text(
+			"AdvSceneSwitcher.generalTab.saveOrLoadsettings.exportWindowTitle"),
+		GetDefaultSettingsSaveLocation(),
+		obs_module_text(
+			"AdvSceneSwitcher.generalTab.saveOrLoadsettings.textType"));
+	if (path.isEmpty()) {
+		return;
+	}
+
+	QFile file(path);
+	if (!file.open(QIODevice::WriteOnly | QIODevice::Text)) {
+		return;
+	}
+	auto out = QTextStream(&file);
+	out << json;
+}
+
+void BackupSettingsOfCurrentVersion()
+{
+	auto sceneCollectionName = obs_frontend_get_current_scene_collection();
+	const std::string fileName =
+		std::string("settings-backup-") +
+		(sceneCollectionName ? sceneCollectionName : "-") + "-" +
+		g_GIT_TAG + ".json";
+	bfree(sceneCollectionName);
+	auto settingsFile = obs_module_config_path(fileName.c_str());
+	if (!settingsFile) {
+		return;
+	}
+
+	QString dirPath = QFileInfo(settingsFile).absolutePath();
+	QDir dir(dirPath);
+	if (!dir.exists()) {
+		if (!dir.mkpath(dirPath)) {
+			blog(LOG_WARNING,
+			     "failed to create directory to save automated backup");
+			bfree(settingsFile);
+			return;
+		}
+	}
+
+	QFile file(settingsFile);
+	if (!file.open(QIODevice::WriteOnly | QIODevice::Text)) {
+		bfree(settingsFile);
+		return;
+	}
+
+	OBSDataAutoRelease data = obs_data_create();
+	SavePluginSettings(data);
+
+	auto settings = obs_data_get_json(data);
+	QString settingsString = QString(settings ? settings : "");
+
+	auto out = QTextStream(&file);
+	out << settingsString;
+	bfree(settingsFile);
+}
+
+} // namespace advss

lib/utils/backup.hpp

@@ -0,0 +1,9 @@
+#pragma once
+#include <QString>
+
+namespace advss {
+
+void AskForBackup(const QString &json);
+void BackupSettingsOfCurrentVersion();
+
+} // namespace advss

lib/utils/plugin-state-helpers.cpp

@@ -3,6 +3,11 @@
 
 namespace advss {
 
+void SavePluginSettings(obs_data_t *obj)
+{
+	GetSwitcher()->SaveSettings(obj);
+}
+
 void LoadPluginSettings(obs_data_t *obj)
 {
 	GetSwitcher()->LoadSettings(obj);

lib/utils/plugin-state-helpers.hpp

@@ -5,6 +5,7 @@
 
 namespace advss {
 
+void SavePluginSettings(obs_data_t *);
 EXPORT void LoadPluginSettings(obs_data_t *);
 
 EXPORT void AddSaveStep(std::function<void(obs_data_t *)>);