chore: remove Singleton & replace getIApp with getApp (#5514)

src/controllers/highlights/HighlightController.hpp

@@ -1,9 +1,10 @@
 #pragma once
 
 #include "common/FlagsEnum.hpp"
-#include "common/Singleton.hpp"
 #include "common/UniqueAccess.hpp"
+#include "singletons/Settings.hpp"
 
+#include <boost/signals2/connection.hpp>
 #include <pajlada/settings.hpp>
 #include <pajlada/settings/settinglistener.hpp>
 #include <QColor>
@@ -20,6 +21,7 @@ class Badge;
 struct MessageParseArgs;
 enum class MessageFlag : int64_t;
 using MessageFlags = FlagsEnum<MessageFlag>;
+class AccountController;
 
 struct HighlightResult {
     HighlightResult(bool _alert, bool _playSound,
@@ -83,10 +85,10 @@ struct HighlightCheck {
     Checker cb;
 };
 
-class HighlightController final : public Singleton
+class HighlightController final
 {
 public:
-    void initialize(Settings &settings, const Paths &paths) override;
+    HighlightController(Settings &settings, AccountController *accounts);
 
     /**
      * @brief Checks the given message parameters if it matches our internal checks, and returns a result
@@ -108,6 +110,7 @@ private:
 
     pajlada::SettingListener rebuildListener_;
     pajlada::Signals::SignalHolder signalHolder_;
+    std::vector<boost::signals2::scoped_connection> bConnections;
 };
 
 }  // namespace chatterino