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PiPedalCommon/src/include/AlsaSequencer.hpp

@@ -26,6 +26,7 @@
 #include <vector>
 #include <string>
 #include <memory>
+#include <functional>
 #include "json.hpp"
 
 namespace pipedal
@@ -331,6 +332,26 @@ namespace pipedal
         virtual void RemoveAllConnections() = 0;
     };
 
+
+    class AlsaSequencerDeviceMonitor {
+    protected:
+        AlsaSequencerDeviceMonitor() {}
+    public:
+        virtual ~AlsaSequencerDeviceMonitor() {}
+
+        using self = AlsaSequencerDeviceMonitor;
+        using ptr = std::shared_ptr<self>;
+        static ptr Create();
+        enum class MonitorAction {
+            DeviceAdded,
+            DeviceRemoved
+        };
+        using Callback = std::function<void(MonitorAction action, int client, const std::string& clientName)>;
+        virtual void StartMonitoring(Callback &&onChangeCallback) = 0;
+        virtual void StopMonitoring() = 0;
+
+    };
+
     std::string RawMidiIdToSequencerId(const std::vector<AlsaSequencerPort> &seqDevices, const std::string &rawMidiId);
 
 }