feat: add event library

CMakeLists.txt

@@ -32,7 +32,7 @@ if (SEALLIB_ASSERT)
 endif()
 
 if (SEALLIB_EVENTS)
-    list(APPEND SEALLIB_SOURCES "src/lib/seallib/events.cpp" "src/lib/seallib/events.h")
+    list(APPEND SEALLIB_SOURCES "src/lib/seallib/events.h")
 endif()
 
 if (SEALLIB_LOG)

src/lib/seallib/events.h

@@ -0,0 +1,76 @@
+#pragma once
+
+#include <vector>
+#include <functional>
+#include <mutex>
+#include <atomic>
+#include <algorithm>
+
+namespace seallib
+{
+    template <typename... T> class Event
+    {
+        public:
+            using CallbackFunc = std::function<void(T...)>;
+            using ConnectionId = size_t;
+
+            ConnectionId addListener(CallbackFunc listener)
+            {
+                std::lock_guard<std::mutex> lock(_mtx);
+                ConnectionId id = ++_nextId;
+                _listeners.push_back({id, std::move(listener)});
+                return id;
+            }
+
+            bool removeListener(ConnectionId id)
+            {
+                std::lock_guard<std::mutex> lock(_mtx);
+
+                auto it =
+                    std::find_if(_listeners.begin(), _listeners.end(), [id](const Listener& l) { return l.id == id; });
+
+                if (it != _listeners.end())
+                {
+                    _listeners.erase(it);
+                    return true;
+                }
+                return false;
+            }
+
+            template <typename... Args> void run(Args&&... args)
+            {
+                std::vector<CallbackFunc> snapshot;
+
+                {
+                    std::lock_guard<std::mutex> lock(_mtx);
+                    snapshot.reserve(_listeners.size());
+                    for (const auto& l : _listeners)
+                    {
+                        snapshot.push_back(l.func);
+                    }
+                }
+
+                for (auto& func : snapshot)
+                {
+                    func(std::forward<Args>(args)...);
+                }
+            }
+
+            void clear()
+            {
+                std::lock_guard<std::mutex> lock(_mtx);
+                _listeners.clear();
+            }
+
+        private:
+            struct Listener
+            {
+                    ConnectionId id;
+                    CallbackFunc func;
+            };
+
+            std::vector<Listener> _listeners;
+            std::mutex _mtx;
+            std::atomic<ConnectionId> _nextId{0};
+    };
+} // namespace seallib