////////////////////////////////////////////////////////////
//
// LuprexViewportClient.cpp
//
////////////////////////////////////////////////////////////

#include "LuprexViewportClient.h"
#include "Common.h"
#include "PlayerControllerBase.h"
#include "Engine/GameInstance.h"
#include "Framework/Application/SlateApplication.h"
#include "Layout/WidgetPath.h"
#include "Widgets/SViewport.h"

UlxViewportClient::UlxViewportClient(const FObjectInitializer &ObjectInitializer)
	: Super(ObjectInitializer)
{
	UE_LOG(LogLuprexIntegration, Display, TEXT("UlxViewportClient constructed"));
}

bool UlxViewportClient::InputKey(const FInputKeyEventArgs &EventArgs)
{
	UE_LOG(LogLuprexIntegration, Display, TEXT("UlxViewportClient::InputKey key=%s event=%d"),
		*EventArgs.Key.ToString(), (int32)EventArgs.Event);

	// Only act on left mouse button presses that bubbled up to the
	// viewport unhandled.  Walk the widget path under the cursor and
	// find the nearest focusable ancestor of whatever was hit.  If it
	// isn't the game viewport itself, hand it to the player controller
	// to apply on its next UpdateInputMode pass; that's the point in
	// the frame where we can override SViewport's own click-focus
	// behaviour without fighting it.
	if ((EventArgs.Event == IE_Pressed) && (EventArgs.Key == EKeys::LeftMouseButton))
	{
		FSlateApplication &Slate = FSlateApplication::Get();
		FVector2D MousePos = Slate.GetCursorPos();
		FWidgetPath Path = Slate.LocateWindowUnderMouse(
			MousePos, Slate.GetInteractiveTopLevelWindows());

		if (Path.IsValid())
		{
			TSharedPtr<SViewport> ViewportWidget = GetGameViewportWidget();
			for (int32 Idx = Path.Widgets.Num() - 1; Idx >= 0; --Idx)
			{
				TSharedRef<SWidget> Widget = Path.Widgets[Idx].Widget;
				if (!Widget->SupportsKeyboardFocus()) continue;
				if (ViewportWidget.IsValid() && Widget == ViewportWidget) break;
				if (UGameInstance *GI = GetGameInstance())
				{
					if (AlxPlayerControllerBase *PC = Cast<AlxPlayerControllerBase>(
						GI->GetFirstLocalPlayerController(GetWorld())))
					{
						PC->ClickToFocus(Widget);
					}
				}
				break;
			}
		}
	}

	return Super::InputKey(EventArgs);
}