/*
===========================================================================
Copyright (C) 1999-2005 Id Software, Inc.

This file is part of Quake III Arena source code.

Quake III Arena source code is free software; you can redistribute it
and/or modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the License,
or (at your option) any later version.

Quake III Arena source code is distributed in the hope that it will be
useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with Quake III Arena source code; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
===========================================================================
*/
/*
** QVK_WIN.C
**
** This file implements the operating system binding of Vulkan to QVulkan function
** pointers.  When doing a port of Quake3 you must implement the following
** two functions:
**
** QVK_Init() - loads libraries, assigns function pointers, etc.
** QVK_Shutdown() - unloads libraries, NULLs function pointers
*/

#ifdef USE_VULKAN_API

#include "../qcommon/q_shared.h"
#include "../qcommon/qcommon.h"
#include "../renderercommon/tr_types.h"
#include "glw_win.h"
#include "win_local.h"

#define VK_USE_PLATFORM_WIN32_KHR
#include "../renderercommon/vulkan/vulkan.h"

static PFN_vkGetInstanceProcAddr qvkGetInstanceProcAddr;
static PFN_vkCreateWin32SurfaceKHR qvkCreateWin32SurfaceKHR;

/*
** QVK_Shutdown
**
** Unloads the specified DLL then nulls out all the proc pointers.  This
** is only called during a hard shutdown of the Vulkan subsystem (e.g. vid_restart).
*/
void QVK_Shutdown( qboolean unloadDLL )
{
	Com_Printf( "...shutting down QVK\n" );

	if ( glw_state.VulkanLib && unloadDLL )
	{
		Com_Printf( "...unloading Vulkan DLL\n" );
		Sys_UnloadLibrary( glw_state.VulkanLib );
		glw_state.VulkanLib = NULL;

		qvkGetInstanceProcAddr = NULL;
	}

	qvkCreateWin32SurfaceKHR = NULL;
}


void *VK_GetInstanceProcAddr( VkInstance instance, const char *name )
{
	return qvkGetInstanceProcAddr( instance, name );
}


qboolean VK_CreateSurface( VkInstance instance, VkSurfaceKHR *pSurface )
{
	VkWin32SurfaceCreateInfoKHR desc;

	qvkCreateWin32SurfaceKHR = /*(PFN_vkCreateWin32SurfaceKHR)*/ VK_GetInstanceProcAddr( instance, "vkCreateWin32SurfaceKHR" );
	if ( !qvkCreateWin32SurfaceKHR )
		return qfalse;

	desc.sType = VK_STRUCTURE_TYPE_WIN32_SURFACE_CREATE_INFO_KHR;
	desc.pNext = NULL;
	desc.flags = 0;
	desc.hinstance = GetModuleHandle( NULL );
	desc.hwnd = g_wv.hWnd;

	if ( qvkCreateWin32SurfaceKHR( instance, &desc, NULL, pSurface ) == VK_SUCCESS )
		return qtrue;
	else
		return qfalse;
}


static HINSTANCE load_vulkan_library( const char *dllname )
{
	HINSTANCE lib;

	lib = Sys_LoadLibrary( dllname );

	if ( lib )
	{
		qvkGetInstanceProcAddr = /*(PFN_vkGetInstanceProcAddr)*/ Sys_LoadFunction( lib, "vkGetInstanceProcAddr" );
		if ( qvkGetInstanceProcAddr )
		{
			return lib;
		}
		Sys_UnloadLibrary( lib );
	}

	return NULL;
}


/*
** QVK_Init
**
** This is responsible for binding our qvk function pointers to 
** the appropriate Vulkan stuff.  In Windows this means doing a 
** LoadLibrary and a bunch of calls to GetProcAddress.  On other
** operating systems we need to do the right thing, whatever that
** might be.
*/
qboolean QVK_Init( void )
{
	Com_Printf( "...initializing QVK\n" );

	if ( glw_state.VulkanLib == NULL )
	{
		const char *dllnames[] = {
			"vulkan-1.dll",
#if idx64
			"amdvlk64.dll",
			"igvk64.dll"
#else
			"amdvlk32.dll",
			"igvk32.dll"
#endif
		};
		int i;

		for ( i = 0; i < ARRAY_LEN( dllnames ); i++ )
		{
			glw_state.VulkanLib = load_vulkan_library( dllnames[i] );

			//Com_Printf( "...loading '%s' : %s\n", dllnames[i], glw_state.VulkanLib ? "success" : "failed" );
			if ( glw_state.VulkanLib )
			{
				char libName[1024];
#ifdef UNICODE
				TCHAR buffer[1024];

				GetModuleFileName( glw_state.VulkanLib, buffer, ARRAY_LEN( buffer ) );
				buffer[ ARRAY_LEN( buffer ) - 1 ] = '\0';
				Q_strncpyz( libName, WtoA( buffer ), sizeof( libName ) );
#else
				GetModuleFileName( glw_state.VulkanLib, libName, sizeof( libName ) );
				libName[ sizeof( libName ) - 1 ] = '\0';
#endif
				Com_Printf( "...loading '%s' : %s\n", libName, "success" );
				break;
			} else {
				Com_Printf( "...loading '%s' : %s\n", dllnames[i], "failed" );
			}
		}

		if ( !glw_state.VulkanLib )
		{
			return qfalse;
		}
	}

	Sys_LoadFunctionErrors(); // reset error counter

	return qtrue;
}
#endif // USE_VULKAN_API