// Copyright Epic Games, Inc. All Rights Reserved.

#pragma once

#include "CoreMinimal.h"
#include "Modules/ModuleManager.h"
#include "IHeadMountedDisplayModule.h"

#include <openxr/openxr.h>

/**
 * The public interface to this module.  In most cases, this interface is only public to sibling modules 
 * within this plugin.
 */
class OPENXRHMD_API IOpenXRHMDModule : public IHeadMountedDisplayModule
{

public:

	/**
	 * Singleton-like access to this module's interface.  This is just for convenience!
	 * Beware of calling this during the shutdown phase, though.  Your module might have been unloaded already.
	 *
	 * @return Returns singleton instance, loading the module on demand if needed
	 */
	static inline IOpenXRHMDModule& Get()
	{
		return FModuleManager::LoadModuleChecked< IOpenXRHMDModule >( "OpenXRHMD" );
	}

	/**
	 * Checks to see if this module is loaded and ready.  It is only valid to call Get() if IsAvailable() returns true.
	 *
	 * @return True if the module is loaded and ready to use
	 */
	static inline bool IsAvailable()
	{
		return FModuleManager::Get().IsModuleLoaded( "OpenXRHMD" );
	}

	virtual bool IsExtensionAvailable(const FString& Name) const = 0;
	virtual bool IsExtensionEnabled(const FString& Name) const = 0;

	virtual bool IsLayerAvailable(const FString& Name) const = 0;
	virtual bool IsLayerEnabled(const FString& Name) const = 0;

	virtual XrInstance GetInstance() const = 0;
	virtual XrSystemId GetSystemId() const = 0;

	virtual FName ResolvePathToName(XrPath Path) = 0;
	virtual XrPath ResolveNameToPath(FName Name) = 0;
};