Address review comments

src/yuzu/play_time_manager.h

@@ -0,0 +1,44 @@
+// SPDX-FileCopyrightText: 2023 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include <QString>
+
+#include <map>
+
+#include "common/common_funcs.h"
+#include "common/common_types.h"
+#include "common/polyfill_thread.h"
+
+namespace PlayTime {
+
+using ProgramId = u64;
+using PlayTime = u64;
+using PlayTimeDatabase = std::map<ProgramId, PlayTime>;
+
+class PlayTimeManager {
+public:
+    explicit PlayTimeManager();
+    ~PlayTimeManager();
+
+    YUZU_NON_COPYABLE(PlayTimeManager);
+    YUZU_NON_MOVEABLE(PlayTimeManager);
+
+    u64 GetPlayTime(u64 program_id) const;
+    void ResetProgramPlayTime(u64 program_id);
+    void SetProgramId(u64 program_id);
+    void Start();
+    void Stop();
+
+private:
+    PlayTimeDatabase database;
+    u64 running_program_id;
+    std::jthread play_time_thread;
+    void AutoTimestamp(std::stop_token stop_token);
+    void Save();
+};
+
+QString ReadablePlayTime(qulonglong time_seconds);
+
+} // namespace PlayTime