diff --git a/src/ai/ai_gui.cpp b/src/ai/ai_gui.cpp
--- a/src/ai/ai_gui.cpp
+++ b/src/ai/ai_gui.cpp
@@ -115,7 +115,7 @@ struct AIConfigWindow : public Window {
 		this->Window::Close();
 	}
 
-	void SetStringParameters(int widget) const override
+	void SetStringParameters(WidgetID widget) const override
 	{
 		switch (widget) {
 			case WID_AIC_NUMBER:
@@ -128,7 +128,7 @@ struct AIConfigWindow : public Window {
 		}
 	}
 
-	void UpdateWidgetSize(int widget, Dimension *size, [[maybe_unused]] const Dimension &padding, [[maybe_unused]] Dimension *fill, [[maybe_unused]] Dimension *resize) override
+	void UpdateWidgetSize(WidgetID widget, Dimension *size, [[maybe_unused]] const Dimension &padding, [[maybe_unused]] Dimension *fill, [[maybe_unused]] Dimension *resize) override
 	{
 		switch (widget) {
 			case WID_AIC_DECREASE_NUMBER:
@@ -165,7 +165,7 @@ struct AIConfigWindow : public Window {
 		return slot < max_slot;
 	}
 
-	void DrawWidget(const Rect &r, int widget) const override
+	void DrawWidget(const Rect &r, WidgetID widget) const override
 	{
 		switch (widget) {
 			case WID_AIC_LIST: {
@@ -190,7 +190,7 @@ struct AIConfigWindow : public Window {
 		}
 	}
 
-	void OnClick([[maybe_unused]] Point pt, int widget, [[maybe_unused]] int click_count) override
+	void OnClick([[maybe_unused]] Point pt, WidgetID widget, [[maybe_unused]] int click_count) override
 	{
 		if (widget >= WID_AIC_TEXTFILE && widget < WID_AIC_TEXTFILE + TFT_CONTENT_END) {
 			if (this->selected_slot == INVALID_COMPANY || AIConfig::GetConfig(this->selected_slot) == nullptr) return;