UICommon: Add NetPlayIndex helper

Source/Core/UICommon/NetPlayIndex.h

@@ -0,0 +1,65 @@
+// Copyright 2019 Dolphin Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <map>
+#include <optional>
+#include <string>
+#include <thread>
+#include <vector>
+
+#include "Common/Flag.h"
+
+struct NetPlaySession
+{
+  std::string name;
+  std::string region;
+  std::string method;
+  std::string server_id;
+  std::string game_id;
+
+  int player_count;
+  int port;
+
+  bool has_password;
+  bool in_game;
+
+  bool EncryptID(const std::string& password);
+  std::optional<std::string> DecryptID(const std::string& password) const;
+};
+
+class NetPlayIndex
+{
+public:
+  explicit NetPlayIndex();
+  ~NetPlayIndex();
+
+  std::optional<std::vector<NetPlaySession>>
+  List(const std::map<std::string, std::string>& filters = {});
+
+  static std::vector<std::string> GetRegions();
+
+  bool Add(NetPlaySession session);
+  void Remove();
+
+  void SetPlayerCount(int player_count);
+  void SetInGame(bool in_game);
+  void SetGame(const std::string& game);
+
+  const std::string& GetLastError() const;
+
+private:
+  void NotificationLoop();
+
+  Common::Flag m_running;
+
+  std::string m_secret;
+  std::string m_game;
+  int m_player_count = 0;
+  bool m_in_game = false;
+
+  std::string m_last_error;
+  std::thread m_session_thread;
+};