#include "Common/VR/OpenXRLoader.h"
#ifdef _WIN32
#include "Common/CommonWindows.h"
#endif

#ifdef XR_NO_PROTOTYPES

PFN_xrGetInstanceProcAddr                  xrGetInstanceProcAddr;
PFN_xrEnumerateApiLayerProperties		   xrEnumerateApiLayerProperties;
PFN_xrEnumerateInstanceExtensionProperties xrEnumerateInstanceExtensionProperties;
PFN_xrCreateInstance					   xrCreateInstance;
PFN_xrDestroyInstance					   xrDestroyInstance;
PFN_xrGetInstanceProperties				   xrGetInstanceProperties;
PFN_xrPollEvent							   xrPollEvent;
PFN_xrResultToString					   xrResultToString;
PFN_xrStructureTypeToString				   xrStructureTypeToString;
PFN_xrGetSystem							   xrGetSystem;
PFN_xrGetSystemProperties				   xrGetSystemProperties;
PFN_xrEnumerateEnvironmentBlendModes	   xrEnumerateEnvironmentBlendModes;
PFN_xrCreateSession						   xrCreateSession;
PFN_xrDestroySession					   xrDestroySession;
PFN_xrEnumerateReferenceSpaces			   xrEnumerateReferenceSpaces;
PFN_xrCreateReferenceSpace				   xrCreateReferenceSpace;
PFN_xrGetReferenceSpaceBoundsRect		   xrGetReferenceSpaceBoundsRect;
PFN_xrCreateActionSpace					   xrCreateActionSpace;
PFN_xrLocateSpace						   xrLocateSpace;
PFN_xrDestroySpace						   xrDestroySpace;
PFN_xrEnumerateViewConfigurations		   xrEnumerateViewConfigurations;
PFN_xrGetViewConfigurationProperties	   xrGetViewConfigurationProperties;
PFN_xrEnumerateViewConfigurationViews	   xrEnumerateViewConfigurationViews;
PFN_xrEnumerateSwapchainFormats			   xrEnumerateSwapchainFormats;
PFN_xrCreateSwapchain					   xrCreateSwapchain;
PFN_xrDestroySwapchain					   xrDestroySwapchain;
PFN_xrEnumerateSwapchainImages			   xrEnumerateSwapchainImages;
PFN_xrAcquireSwapchainImage				   xrAcquireSwapchainImage;
PFN_xrWaitSwapchainImage				   xrWaitSwapchainImage;
PFN_xrReleaseSwapchainImage				   xrReleaseSwapchainImage;
PFN_xrBeginSession						   xrBeginSession;
PFN_xrEndSession						   xrEndSession;
PFN_xrRequestExitSession				   xrRequestExitSession;
PFN_xrWaitFrame							   xrWaitFrame;
PFN_xrBeginFrame						   xrBeginFrame;
PFN_xrEndFrame							   xrEndFrame;
PFN_xrLocateViews						   xrLocateViews;
PFN_xrStringToPath						   xrStringToPath;
PFN_xrPathToString						   xrPathToString;
PFN_xrCreateActionSet					   xrCreateActionSet;
PFN_xrDestroyActionSet					   xrDestroyActionSet;
PFN_xrCreateAction						   xrCreateAction;
PFN_xrDestroyAction						   xrDestroyAction;
PFN_xrSuggestInteractionProfileBindings	   xrSuggestInteractionProfileBindings;
PFN_xrAttachSessionActionSets			   xrAttachSessionActionSets;
PFN_xrGetCurrentInteractionProfile		   xrGetCurrentInteractionProfile;
PFN_xrGetActionStateBoolean				   xrGetActionStateBoolean;
PFN_xrGetActionStateFloat				   xrGetActionStateFloat;
PFN_xrGetActionStateVector2f			   xrGetActionStateVector2f;
PFN_xrGetActionStatePose				   xrGetActionStatePose;
PFN_xrSyncActions						   xrSyncActions;
PFN_xrEnumerateBoundSourcesForAction	   xrEnumerateBoundSourcesForAction;
PFN_xrGetInputSourceLocalizedName		   xrGetInputSourceLocalizedName;
PFN_xrApplyHapticFeedback				   xrApplyHapticFeedback;
PFN_xrStopHapticFeedback				   xrStopHapticFeedback;

#ifdef XR_USE_PLATFORM_WIN32
#define dlsym(x, y) GetProcAddress(x, y)
static HMODULE g_xrLibrary;
#else
#define dlsym(x, y) nullptr
void *g_xrLibrary;
#endif

#define LOAD_INSTANCE_FUNC(name) (PFN_ ## name)xrGetInstanceProcAddr(instance, #name, (PFN_xrVoidFunction *)(&name))


bool XRLoad() {
	if (g_xrLibrary) {
		// Already loaded. That's OK.
		return true;
	}

#ifdef XR_USE_PLATFORM_WIN32
	g_xrLibrary = LoadLibrary(L"openxr_loader.dll");
	if (!g_xrLibrary) {
		return false;
	}
#else
	return false;
#endif

	// Load the three basic functions.
	xrGetInstanceProcAddr = (PFN_xrGetInstanceProcAddr)dlsym(g_xrLibrary, "xrGetInstanceProcAddr");
	xrEnumerateApiLayerProperties = (PFN_xrEnumerateApiLayerProperties)dlsym(g_xrLibrary, "xrEnumerateApiLayerProperties");
	xrEnumerateInstanceExtensionProperties = (PFN_xrEnumerateInstanceExtensionProperties)dlsym(g_xrLibrary, "xrEnumerateInstanceExtensionProperties");

	// Load the rest.
	return true;
}

void XRLoadInstanceFunctions(XrInstance instance) {
	LOAD_INSTANCE_FUNC(xrCreateInstance);
	LOAD_INSTANCE_FUNC(xrGetInstanceProcAddr);
	LOAD_INSTANCE_FUNC(xrEnumerateApiLayerProperties);
	LOAD_INSTANCE_FUNC(xrEnumerateInstanceExtensionProperties);
	LOAD_INSTANCE_FUNC(xrCreateInstance);
	LOAD_INSTANCE_FUNC(xrDestroyInstance);
	LOAD_INSTANCE_FUNC(xrGetInstanceProperties);
	LOAD_INSTANCE_FUNC(xrPollEvent);
	LOAD_INSTANCE_FUNC(xrResultToString);
	LOAD_INSTANCE_FUNC(xrStructureTypeToString);
	LOAD_INSTANCE_FUNC(xrGetSystem);
	LOAD_INSTANCE_FUNC(xrGetSystemProperties);
	LOAD_INSTANCE_FUNC(xrEnumerateEnvironmentBlendModes);
	LOAD_INSTANCE_FUNC(xrCreateSession);
	LOAD_INSTANCE_FUNC(xrDestroySession);
	LOAD_INSTANCE_FUNC(xrEnumerateReferenceSpaces);
	LOAD_INSTANCE_FUNC(xrCreateReferenceSpace);
	LOAD_INSTANCE_FUNC(xrGetReferenceSpaceBoundsRect);
	LOAD_INSTANCE_FUNC(xrCreateActionSpace);
	LOAD_INSTANCE_FUNC(xrLocateSpace);
	LOAD_INSTANCE_FUNC(xrDestroySpace);
	LOAD_INSTANCE_FUNC(xrEnumerateViewConfigurations);
	LOAD_INSTANCE_FUNC(xrGetViewConfigurationProperties);
	LOAD_INSTANCE_FUNC(xrEnumerateViewConfigurationViews);
	LOAD_INSTANCE_FUNC(xrEnumerateSwapchainFormats);
	LOAD_INSTANCE_FUNC(xrCreateSwapchain);
	LOAD_INSTANCE_FUNC(xrDestroySwapchain);
	LOAD_INSTANCE_FUNC(xrEnumerateSwapchainImages);
	LOAD_INSTANCE_FUNC(xrAcquireSwapchainImage);
	LOAD_INSTANCE_FUNC(xrWaitSwapchainImage);
	LOAD_INSTANCE_FUNC(xrReleaseSwapchainImage);
	LOAD_INSTANCE_FUNC(xrBeginSession);
	LOAD_INSTANCE_FUNC(xrEndSession);
	LOAD_INSTANCE_FUNC(xrRequestExitSession);
	LOAD_INSTANCE_FUNC(xrWaitFrame);
	LOAD_INSTANCE_FUNC(xrBeginFrame);
	LOAD_INSTANCE_FUNC(xrEndFrame);
	LOAD_INSTANCE_FUNC(xrLocateViews);
	LOAD_INSTANCE_FUNC(xrStringToPath);
	LOAD_INSTANCE_FUNC(xrPathToString);
	LOAD_INSTANCE_FUNC(xrCreateActionSet);
	LOAD_INSTANCE_FUNC(xrDestroyActionSet);
	LOAD_INSTANCE_FUNC(xrCreateAction);
	LOAD_INSTANCE_FUNC(xrDestroyAction);
	LOAD_INSTANCE_FUNC(xrSuggestInteractionProfileBindings);
	LOAD_INSTANCE_FUNC(xrAttachSessionActionSets);
	LOAD_INSTANCE_FUNC(xrGetCurrentInteractionProfile);
	LOAD_INSTANCE_FUNC(xrGetActionStateBoolean);
	LOAD_INSTANCE_FUNC(xrGetActionStateFloat);
	LOAD_INSTANCE_FUNC(xrGetActionStateVector2f);
	LOAD_INSTANCE_FUNC(xrGetActionStatePose);
	LOAD_INSTANCE_FUNC(xrSyncActions);
	LOAD_INSTANCE_FUNC(xrEnumerateBoundSourcesForAction);
	LOAD_INSTANCE_FUNC(xrGetInputSourceLocalizedName);
	LOAD_INSTANCE_FUNC(xrApplyHapticFeedback);
	LOAD_INSTANCE_FUNC(xrStopHapticFeedback);

	// TODO: Load any extensions we need, too.
}

#endif