[Installer][Client] Back up user data before old uninstallers can delete it

libcockatrice_utility/libcockatrice/utility/user_data_backup.cpp

@@ -0,0 +1,93 @@
+#include "user_data_backup.h"
+
+#include <QDateTime>
+#include <QDir>
+#include <QDirIterator>
+#include <QFile>
+#include <QFileInfo>
+#include <QStandardPaths>
+
+namespace UserDataBackup
+{
+
+bool copyDirectoryRecursively(const QString &sourceDir, const QString &destDir)
+{
+    QDir source(sourceDir);
+    if (!source.exists()) {
+        return false;
+    }
+    if (!QDir().mkpath(destDir)) {
+        return false;
+    }
+
+    bool ok = true;
+    QDirIterator it(sourceDir, QDir::Files | QDir::Dirs | QDir::NoDotAndDotDot | QDir::Hidden,
+                    QDirIterator::Subdirectories);
+    while (it.hasNext()) {
+        it.next();
+        QString entryRel = source.relativeFilePath(it.filePath());
+        QString target = QDir(destDir).absoluteFilePath(entryRel);
+        if (it.fileInfo().isDir()) {
+            if (!QDir().mkpath(target)) {
+                ok = false;
+            }
+        } else {
+            if (QFile::exists(target) && !QFile::remove(target)) {
+                ok = false;
+                continue;
+            }
+            if (!QFile::copy(it.filePath(), target)) {
+                ok = false;
+            }
+        }
+    }
+    return ok;
+}
+
+bool backupAtRiskPath(const QString &sourcePath, const QString &backupRoot, QString *backupLocationOut)
+{
+    QFileInfo source(sourcePath);
+    if (!source.exists()) {
+        return false;
+    }
+    QString timestamp = QDateTime::currentDateTime().toString("yyyyMMdd-hhmmss");
+    QString backupDir = QDir(backupRoot).absoluteFilePath("CockatriceDataBackup-" + timestamp);
+    if (!QDir().mkpath(backupDir)) {
+        return false;
+    }
+
+    bool ok;
+    QString backupLocation;
+    if (source.isDir()) {
+        backupLocation = QDir(backupDir).absoluteFilePath(source.fileName());
+        ok = copyDirectoryRecursively(sourcePath, backupLocation);
+    } else {
+        backupLocation = QDir(backupDir).absoluteFilePath(source.fileName());
+        if (QFile::exists(backupLocation)) {
+            QFile::remove(backupLocation);
+        }
+        ok = QFile::copy(sourcePath, backupLocation);
+    }
+    if (!ok) {
+        return false;
+    }
+    if (backupLocationOut) {
+        *backupLocationOut = backupLocation;
+    }
+    return true;
+}
+
+QString defaultBackupRoot()
+{
+    QString documents = QStandardPaths::writableLocation(QStandardPaths::DocumentsLocation);
+    if (!documents.isEmpty()) {
+        return QDir(documents).absoluteFilePath("CockatriceBackups");
+    }
+    QString appData = QStandardPaths::writableLocation(QStandardPaths::AppLocalDataLocation);
+    if (!appData.isEmpty()) {
+        return QDir(appData).absoluteFilePath("../CockatriceBackups");
+    }
+    return QDir::temp().absoluteFilePath("CockatriceBackups");
+}
+
+} // namespace UserDataBackup