/*
vid_sdl.c - SDL vid component
Copyright (C) 2018 a1batross

This program 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 3 of the License, or
(at your option) any later version.

This program 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.
*/
#if !XASH_DEDICATED
#include <SDL.h>
#include "common.h"
#include "client.h"
#include "vid_common.h"
#include "platform/sdl/events.h"

static vidmode_t *vidmodes = NULL;
static int num_vidmodes = 0;
static void GL_SetupAttributes( void );
struct
{
	int prev_width, prev_height;
} sdlState = { 640, 480 };

struct
{
#if SDL_VERSION_ATLEAST(2, 0, 0)
	SDL_Renderer *renderer;
	SDL_Texture *tex;
#endif
	int width, height;
	SDL_Surface *surf;
	SDL_Surface *win;
} sw;

qboolean SW_CreateBuffer( int width, int height, uint *stride, uint *bpp, uint *r, uint *g, uint *b )
{
	sw.width = width;
	sw.height = height;

#if SDL_VERSION_ATLEAST(2, 0, 0)
	if( sw.renderer )
	{
		unsigned int format = SDL_GetWindowPixelFormat( host.hWnd );
		SDL_RenderSetLogicalSize(sw.renderer, refState.width, refState.height);

		if( sw.tex )
			SDL_DestroyTexture( sw.tex );

		// guess
		if( format == SDL_PIXELFORMAT_UNKNOWN )
		{
			if( refState.desktopBitsPixel == 16 )
				format = SDL_PIXELFORMAT_RGB565;
			else
				format = SDL_PIXELFORMAT_RGBA8888;
		}

		// we can only copy fast 16 or 32 bits
		// SDL_Renderer does not allow zero-copy, so 24 bits will be ineffective
		if( !( SDL_BYTESPERPIXEL(format) == 2 || SDL_BYTESPERPIXEL(format) == 4 ) )
			format = SDL_PIXELFORMAT_RGBA8888;

		sw.tex = SDL_CreateTexture(sw.renderer, format,
										SDL_TEXTUREACCESS_STREAMING,
										width, height);

		// fallback
		if( !sw.tex && format != SDL_PIXELFORMAT_RGBA8888 )
		{
			format = SDL_PIXELFORMAT_RGBA8888;
			sw.tex = SDL_CreateTexture(sw.renderer, format,
											SDL_TEXTUREACCESS_STREAMING,
											width, height);
		}

		if( !sw.tex )
		{
			SDL_DestroyRenderer( sw.renderer );
			sw.renderer = NULL;
		}
		else
		{
			void *pixels;
			int pitch;

			if( !SDL_LockTexture(sw.tex, NULL, &pixels, &pitch ) )
			{
				int bits;
				uint amask;
				// lock successfull, release
				SDL_UnlockTexture(sw.tex);

				// enough for building blitter tables
				SDL_PixelFormatEnumToMasks( format, &bits, r, g, b, &amask );
				*bpp = SDL_BYTESPERPIXEL(format);
				*stride = pitch / *bpp;

				return true;
			}

			// fallback to surf
			SDL_DestroyTexture(sw.tex);
			sw.tex = NULL;
			SDL_DestroyRenderer(sw.renderer);
			sw.renderer = NULL;
		}
	}
#endif

#if SDL_VERSION_ATLEAST( 2, 0, 0 )
	if( !sw.renderer )
	{
		sw.win = SDL_GetWindowSurface( host.hWnd );
#else // SDL_VERSION_ATLEAST( 2, 0, 0 )
	{
		sw.win = SDL_GetVideoSurface();
#endif

		// sdl will create renderer if hw framebuffer unavailiable, so cannot fallback here
		// if it is failed, it is not possible to draw with SDL in REF_SOFTWARE mode
		if( !sw.win )
		{
			Sys_Warn("failed to initialize software output, try enable sw_glblit");
			return false;
		}

		*bpp = sw.win->format->BytesPerPixel;
		*r = sw.win->format->Rmask;
		*g = sw.win->format->Gmask;
		*b = sw.win->format->Bmask;
		*stride = sw.win->pitch / sw.win->format->BytesPerPixel;

		/// TODO: check somehow if ref_soft can handle native format
#if 0
		{
			sw.surf = SDL_CreateRGBSurfaceWithFormat( 0, width, height, 16, SDL_PIXELFORMAT_RGB565 );
			if( !sw.surf )
				Sys_Error(SDL_GetError());
		}
#endif
	}

	// we can't create ref_soft buffer
	return false;
}

void *SW_LockBuffer( void )
{
#if SDL_VERSION_ATLEAST( 2, 0, 0 )
	if( sw.renderer )
	{
		void *pixels;
		int stride;

		if( SDL_LockTexture(sw.tex, NULL, &pixels, &stride ) )
			Sys_Error("%s", SDL_GetError());
		return pixels;
	}

	// ensure it not changed (do we really need this?)
	sw.win = SDL_GetWindowSurface( host.hWnd );
	//if( !sw.win )
		//SDL_GetWindowSurface( host.hWnd );
#else // SDL_VERSION_ATLEAST( 2, 0, 0 )
	sw.win = SDL_GetVideoSurface();
#endif // SDL_VERSION_ATLEAST( 2, 0, 0 )

	// prevent buffer overrun
	if( !sw.win || sw.win->w < sw.width || sw.win->h < sw.height  )
		return NULL;

#if SDL_VERSION_ATLEAST( 2, 0, 0 )
	if( sw.surf )
	{
		SDL_LockSurface( sw.surf );
		return sw.surf->pixels;
	}
	else
#endif // SDL_VERSION_ATLEAST( 2, 0, 0 )
	{
		// real window pixels (x11 shm region, dma buffer, etc)
		// or SDL_Renderer texture if not supported
		SDL_LockSurface( sw.win );
		return sw.win->pixels;
	}
}

void SW_UnlockBuffer( void )
{
#if SDL_VERSION_ATLEAST( 2, 0, 0 )
	if( sw.renderer )
	{
		SDL_Rect src, dst;
		src.x = src.y = 0;
		src.w = sw.width;
		src.h = sw.height;
		dst = src;
		SDL_UnlockTexture(sw.tex);

		SDL_SetTextureBlendMode(sw.tex, SDL_BLENDMODE_NONE);


		SDL_RenderCopy(sw.renderer, sw.tex, &src, &dst);
		SDL_RenderPresent(sw.renderer);

		return;
		//Con_Printf("%s\n", SDL_GetError());
	}

	// blit if blitting surface availiable
	if( sw.surf )
	{
		SDL_Rect src, dst;
		src.x = src.y = 0;
		src.w = sw.width;
		src.h = sw.height;
		dst = src;
		SDL_UnlockSurface( sw.surf );
		SDL_BlitSurface( sw.surf, &src, sw.win, &dst );
		return;
	}
#endif // SDL_VERSION_ATLEAST( 2, 0, 0 )

	// already blitted
	SDL_UnlockSurface( sw.win );

#if SDL_VERSION_ATLEAST( 2, 0, 0 )
	SDL_UpdateWindowSurface( host.hWnd );
#else // SDL_VERSION_ATLEAST( 2, 0, 0 )
	SDL_Flip( host.hWnd );
#endif
}

int R_MaxVideoModes( void )
{
	return num_vidmodes;
}

vidmode_t *R_GetVideoMode( int num )
{
	if( !vidmodes || num < 0 || num >= R_MaxVideoModes() )
	{
		return NULL;
	}

	return vidmodes + num;
}

static void R_InitVideoModes( void )
{
	char buf[MAX_VA_STRING];
#if SDL_VERSION_ATLEAST( 2, 0, 0 )
	int displayIndex = 0; // TODO: handle multiple displays somehow
	int i, modes;

	num_vidmodes = 0;
	modes = SDL_GetNumDisplayModes( displayIndex );

	if( !modes )
		return;

	vidmodes = Mem_Malloc( host.mempool, modes * sizeof( vidmode_t ) );

	for( i = 0; i < modes; i++ )
	{
		int j;
		SDL_DisplayMode mode;

		if( SDL_GetDisplayMode( displayIndex, i, &mode ) )
		{
			Msg( "SDL_GetDisplayMode: %s\n", SDL_GetError() );
			continue;
		}

		if( mode.w < VID_MIN_WIDTH || mode.h < VID_MIN_HEIGHT )
			continue;

		for( j = 0; j < num_vidmodes; j++ )
		{
			if( mode.w == vidmodes[j].width &&
				mode.h == vidmodes[j].height )
			{
				break;
			}
		}
		if( j != num_vidmodes )
			continue;

		vidmodes[num_vidmodes].width = mode.w;
		vidmodes[num_vidmodes].height = mode.h;
		Q_snprintf( buf, sizeof( buf ), "%ix%i", mode.w, mode.h );
		vidmodes[num_vidmodes].desc = copystring( buf );

		num_vidmodes++;
	}
#else // SDL_VERSION_ATLEAST( 2, 0, 0 )
	SDL_Rect **modes;
	int len = 0, i = 0, j;

	modes = SDL_ListModes( NULL, SDL_FULLSCREEN );

	if( !modes || modes == (void*)-1 )
		return;

	for( len = 0; modes[len]; len++ );

	vidmodes = Mem_Malloc( host.mempool, len * sizeof( vidmode_t ) );

	// from smallest to largest
	for( ; i < len; i++ )
	{
		SDL_Rect *mode = modes[len - i - 1];

		for( j = 0; j < num_vidmodes; j++ )
		{
			if( mode->w == vidmodes[j].width &&
				mode->h == vidmodes[j].height )
			{
				break;
			}
		}
		if( j != num_vidmodes )
			continue;

		vidmodes[num_vidmodes].width = mode->w;
		vidmodes[num_vidmodes].height = mode->h;
		Q_snprintf( buf, sizeof( buf ), "%ix%i", mode->w, mode->h );
		vidmodes[num_vidmodes].desc = copystring( buf );

		num_vidmodes++;
	}
#endif // SDL_VERSION_ATLEAST( 2, 0, 0 )

}

static void R_FreeVideoModes( void )
{
	int i;

	if( !vidmodes )
		return;

	for( i = 0; i < num_vidmodes; i++ )
		Mem_Free( (char*)vidmodes[i].desc );
	Mem_Free( vidmodes );

	vidmodes = NULL;
}

#if XASH_WIN32
typedef enum _XASH_DPI_AWARENESS
{
	XASH_DPI_UNAWARE = 0,
	XASH_SYSTEM_DPI_AWARE = 1,
	XASH_PER_MONITOR_DPI_AWARE = 2
} XASH_DPI_AWARENESS;

static void WIN_SetDPIAwareness( void )
{
	HMODULE hModule;
	HRESULT ( __stdcall *pSetProcessDpiAwareness )( XASH_DPI_AWARENESS );
	BOOL ( __stdcall *pSetProcessDPIAware )( void );
	BOOL bSuccess = FALSE;

	if( ( hModule = LoadLibrary( "shcore.dll" ) ) )
	{
		if( ( pSetProcessDpiAwareness = (void*)GetProcAddress( hModule, "SetProcessDpiAwareness" ) ) )
		{
			// I hope SDL don't handle WM_DPICHANGED message
			HRESULT hResult = pSetProcessDpiAwareness( XASH_SYSTEM_DPI_AWARE );

			if( hResult == S_OK )
			{
				Con_Reportf( "SetDPIAwareness: Success\n" );
				bSuccess = TRUE;
			}
			else if( hResult == E_INVALIDARG ) Con_Reportf( "SetDPIAwareness: Invalid argument\n" );
			else if( hResult == E_ACCESSDENIED ) Con_Reportf( "SetDPIAwareness: Access Denied\n" );
		}
		else Con_Reportf( "SetDPIAwareness: Can't get SetProcessDpiAwareness\n" );
		FreeLibrary( hModule );
	}
	else Con_Reportf( "SetDPIAwareness: Can't load shcore.dll\n" );


	if( !bSuccess )
	{
		Con_Reportf( "SetDPIAwareness: Trying SetProcessDPIAware...\n" );

		if( ( hModule = LoadLibrary( "user32.dll" ) ) )
		{
			if( ( pSetProcessDPIAware = ( void* )GetProcAddress( hModule, "SetProcessDPIAware" ) ) )
			{
				// I hope SDL don't handle WM_DPICHANGED message
				BOOL hResult = pSetProcessDPIAware();

				if( hResult )
				{
					Con_Reportf( "SetDPIAwareness: Success\n" );
					bSuccess = TRUE;
				}
				else Con_Reportf( "SetDPIAwareness: fail\n" );
			}
			else Con_Reportf( "SetDPIAwareness: Can't get SetProcessDPIAware\n" );
			FreeLibrary( hModule );
		}
		else Con_Reportf( "SetDPIAwareness: Can't load user32.dll\n" );
	}
}

#include <SDL_syswm.h>
static qboolean WIN_SetWindowIcon( HICON ico )
{
	SDL_SysWMinfo wminfo;

	if( SDL_GetWindowWMInfo( host.hWnd, &wminfo ))
	{
		SendMessage( wminfo.info.win.window, WM_SETICON, ICON_SMALL, (LONG_PTR)ico );
		SendMessage( wminfo.info.win.window, WM_SETICON, ICON_BIG, (LONG_PTR)ico );
		return true;
	}
	return false;
}
#endif


/*
=================
GL_GetProcAddress
=================
*/
void *GL_GetProcAddress( const char *name )
{
	void *func = SDL_GL_GetProcAddress( name );
#if !SDL_VERSION_ATLEAST( 2, 0, 6 ) && XASH_POSIX
	if( !func && Sys_CheckParm( "-egl" ))
	{
		/*
		 * SDL2 has broken SDL_GL_GetProcAddress until this commit if using egl:
		 * https://github.com/libsdl-org/SDL/commit/466ba57d42d244e80357e9ad3011c50af30ed225
		 * so call eglGetProcAddress directly
		 * */
		static void *(*peglGetProcAddress)( const char * );
		if( !peglGetProcAddress )
		{
			void *lib = dlopen( "libEGL.so", RTLD_NOW );
			if( lib )
				*(void**)&peglGetProcAddress = dlsym( lib, "eglGetProcAddress" );
		}
		if( peglGetProcAddress )
			func = peglGetProcAddress( name );
	}
#endif

#if XASH_PSVITA
	// try to find in main module
	if( !func )
	{
		func = dlsym( NULL, name );
	}
#endif

	if( !func )
	{
		Con_Reportf( S_ERROR "GL_GetProcAddress failed for %s\n", name );
	}

	return func;
}

/*
===============
GL_UpdateSwapInterval
===============
*/
void GL_UpdateSwapInterval( void )
{
#if SDL_VERSION_ATLEAST( 2, 0, 0 )
	// disable VSync while level is loading
	if( cls.state < ca_active )
	{
		SDL_GL_SetSwapInterval( 0 );
		SetBits( gl_vsync.flags, FCVAR_CHANGED );
	}
	else if( FBitSet( gl_vsync.flags, FCVAR_CHANGED ))
	{
		ClearBits( gl_vsync.flags, FCVAR_CHANGED );

		if( SDL_GL_SetSwapInterval( gl_vsync.value ) )
			Con_Reportf( S_ERROR  "SDL_GL_SetSwapInterval: %s\n", SDL_GetError( ) );
	}
#endif // SDL_VERSION_ATLEAST( 2, 0, 0 )
}

/*
=================
GL_DeleteContext

always return false
=================
*/
qboolean GL_DeleteContext( void )
{
#if SDL_VERSION_ATLEAST( 2, 0, 0 )
	if( glw_state.context )
	{
		SDL_GL_DeleteContext(glw_state.context);
		glw_state.context = NULL;
	}
#endif // SDL_VERSION_ATLEAST( 2, 0, 0 )
	return false;
}

/*
=================
GL_CreateContext
=================
*/
static qboolean GL_CreateContext( void )
{
#if SDL_VERSION_ATLEAST(2, 0, 0)
	if( ( glw_state.context = SDL_GL_CreateContext( host.hWnd ) ) == NULL)
	{
		Con_Reportf( S_ERROR "GL_CreateContext: %s\n", SDL_GetError());
		return GL_DeleteContext();
	}
#endif // SDL_VERSION_ATLEAST( 2, 0, 0 )
	return true;
}

/*
=================
GL_UpdateContext
=================
*/
static qboolean GL_UpdateContext( void )
{
#if SDL_VERSION_ATLEAST( 2, 0, 0 )
	if( SDL_GL_MakeCurrent( host.hWnd, glw_state.context ))
	{
		Con_Reportf( S_ERROR "GL_UpdateContext: %s\n", SDL_GetError());
		return GL_DeleteContext();
	}
#endif // SDL_VERSION_ATLEAST( 2, 0, 0 )
	return true;
}

void VID_SaveWindowSize( int width, int height, qboolean maximized )
{
	int render_w = width, render_h = height;

#if SDL_VERSION_ATLEAST( 2, 0, 0 )
	if( !glw_state.software )
		SDL_GL_GetDrawableSize( host.hWnd, &render_w, &render_h );
	else
		SDL_RenderSetLogicalSize( sw.renderer, width, height );
#endif

	VID_SetDisplayTransform( &render_w, &render_h );
	R_SaveVideoMode( width, height, render_w, render_h, maximized );
}

static qboolean VID_SetScreenResolution( int width, int height, window_mode_t window_mode )
{
#if SDL_VERSION_ATLEAST( 2, 0, 0 )
	SDL_DisplayMode got;
	Uint32 wndFlags = 0;

#if !XASH_APPLE
	if( vid_highdpi.value )
		SetBits( wndFlags, SDL_WINDOW_ALLOW_HIGHDPI );
#endif

	SDL_SetWindowBordered( host.hWnd, SDL_FALSE );

	if( window_mode == WINDOW_MODE_BORDERLESS )
	{
		if( SDL_GetDesktopDisplayMode( 0, &got ) < 0 )
		{
			Con_Printf( S_ERROR "%s: SDL_GetDesktopDisplayMode: %s", __func__, SDL_GetError( ));
			return false;
		}

		if( SDL_SetWindowFullscreen( host.hWnd, SDL_WINDOW_FULLSCREEN_DESKTOP ) < 0 )
		{
			Con_Printf( S_ERROR "%s: SDL_SetWindowFullscreen (borderless): %s", __func__, SDL_GetError( ));
			return false;
		}
	}
	else if( window_mode == WINDOW_MODE_FULLSCREEN )
	{
		SDL_DisplayMode want = { 0 };
		want.w = width;
		want.h = height;

		if( SDL_GetClosestDisplayMode( 0, &want, &got ) < 0 )
		{
			Con_Printf( S_ERROR "%s: SDL_GetClosestDisplayMode: %s", __func__, SDL_GetError( ));
			return false;
		}

		if( got.w != want.w || got.h != want.h )
			Con_Reportf( S_NOTE "Got closest display mode: %ix%i@%i\n", got.w, got.h, got.refresh_rate );

		if( SDL_SetWindowDisplayMode( host.hWnd, &got ) < 0 )
		{
			Con_Printf( S_ERROR "%s: SDL_SetWindowDisplayMode: %s", __func__, SDL_GetError( ));
			return false;
		}

		if( SDL_SetWindowFullscreen( host.hWnd, SDL_WINDOW_FULLSCREEN ) < 0 )
		{
			Con_Printf( S_ERROR "%s: SDL_SetWindowFullscreen (fullscreen): %s", __func__, SDL_GetError( ));
			return false;
		}
	}

	SDL_SetWindowSize( host.hWnd, got.w, got.h );
	VID_SaveWindowSize( got.w, got.h, true );
#else
	VID_SaveWindowSize( width, height, true );
#endif
	return true;
}

void VID_RestoreScreenResolution( void )
{
#if SDL_VERSION_ATLEAST( 2, 0, 0 )
	switch((window_mode_t)vid_fullscreen.value )
	{
	case WINDOW_MODE_WINDOWED:
		SDL_SetWindowBordered( host.hWnd, SDL_TRUE );
		break;
	default:
		SDL_MinimizeWindow( host.hWnd );
		SDL_SetWindowFullscreen( host.hWnd, 0 );
		break;
	}
#endif // SDL_VERSION_ATLEAST( 2, 0, 0 )
}

static void VID_SetWindowIcon( SDL_Window *hWnd )
{
#if SDL_VERSION_ATLEAST( 2, 0, 0 )
	rgbdata_t *icon = NULL;
	char iconpath[MAX_STRING];
	const char *localIcoPath;

#if XASH_WIN32 // ICO support only for Win32
	if(( localIcoPath = FS_GetDiskPath( GI->iconpath, true )))
	{
		HICON ico = (HICON)LoadImage( NULL, localIcoPath, IMAGE_ICON, 0, 0, LR_LOADFROMFILE|LR_DEFAULTSIZE );
		if( ico && WIN_SetWindowIcon( ico ))
			return;
	}
#endif // _WIN32 && !XASH_64BIT

	Q_strncpy( iconpath, GI->iconpath, sizeof( iconpath ));
	COM_ReplaceExtension( iconpath, ".tga", sizeof( iconpath ));
	icon = FS_LoadImage( iconpath, NULL, 0 );

	if( icon )
	{
		SDL_Surface *surface = SDL_CreateRGBSurfaceFrom( icon->buffer,
			icon->width, icon->height, 32, 4 * icon->width,
			0x000000ff, 0x0000ff00, 0x00ff0000,	0xff000000 );

		if( surface )
		{
			SDL_SetWindowIcon( host.hWnd, surface );
			SDL_FreeSurface( surface );
			FS_FreeImage( icon );
			return;
		}

		FS_FreeImage( icon );
	}

#if XASH_WIN32 // ICO support only for Win32
	WIN_SetWindowIcon( LoadIcon( host.hInst, MAKEINTRESOURCE( 101 )));
#endif
#endif // SDL_VERSION_ATLEAST( 2, 0, 0 )
}

static qboolean VID_CreateWindowWithSafeGL( const char *wndname, int xpos, int ypos, int w, int h, uint32_t flags )
{
	while( glw_state.safe >= SAFE_NO && glw_state.safe < SAFE_LAST )
	{
#if SDL_VERSION_ATLEAST( 2, 0, 0 )
		host.hWnd = SDL_CreateWindow( wndname, xpos, ypos, w, h, flags );
#else
		host.hWnd = sw.surf = SDL_SetVideoMode( width, height, 16, flags );
#endif
		// we have window, exit loop
		if( host.hWnd )
			break;

		Con_Reportf( S_ERROR "VID_CreateWindow: couldn't create '%s' with safegl level %d: %s\n", wndname, glw_state.safe, SDL_GetError());

		glw_state.safe++;

		if( !gl_msaa_samples.value && glw_state.safe == SAFE_NOMSAA )
			glw_state.safe++; // no need to skip msaa, if we already disabled it

		GL_SetupAttributes(); // re-choose attributes

		// try again create window
	}

	// window creation has failed...
	if( glw_state.safe >= SAFE_LAST )
		return false;

	return true;
}

/*
=================
VID_CreateWindow
=================
*/
qboolean VID_CreateWindow( int width, int height, window_mode_t window_mode )
{
	string wndname;
#if SDL_VERSION_ATLEAST( 2, 0, 0 )
	qboolean maximized = vid_maximized.value != 0.0f;
	Uint32 wndFlags = SDL_WINDOW_SHOWN | SDL_WINDOW_MOUSE_FOCUS;
	int xpos, ypos;

	Q_strncpy( wndname, GI->title, sizeof( wndname ));

	if( vid_highdpi.value )
		SetBits( wndFlags, SDL_WINDOW_ALLOW_HIGHDPI );
	if( !glw_state.software )
		SetBits( wndFlags, SDL_WINDOW_OPENGL );

#if !XASH_MOBILE_PLATFORM
	if( window_mode == WINDOW_MODE_WINDOWED )
	{
		SDL_Rect r;

		SetBits( wndFlags, SDL_WINDOW_RESIZABLE );
		if( maximized )
			SetBits( wndFlags, SDL_WINDOW_MAXIMIZED );

#if SDL_VERSION_ATLEAST( 2, 0, 5 )
		if( SDL_GetDisplayUsableBounds( 0, &r ) < 0 &&
			SDL_GetDisplayBounds( 0, &r ) < 0 )
#else
		if( SDL_GetDisplayBounds( 0, &r ) < 0 )
#endif
		{
			Con_Reportf( S_ERROR "VID_CreateWindow: SDL_GetDisplayBounds failed: %s\n", SDL_GetError( ));
			xpos = SDL_WINDOWPOS_CENTERED;
			ypos = SDL_WINDOWPOS_CENTERED;
		}
		else
		{
			xpos = window_xpos.value;
			ypos = window_ypos.value;

			// don't create window outside of usable display space
			if( xpos < r.x || xpos + width > r.x + r.w )
				xpos = SDL_WINDOWPOS_CENTERED;

			if( ypos < r.y || ypos + height > r.y + r.h )
				ypos = SDL_WINDOWPOS_CENTERED;
		}
	}
	else
	{
		if( window_mode == WINDOW_MODE_FULLSCREEN )
			// need input grab only in true fullscreen mode
			SetBits( wndFlags, SDL_WINDOW_FULLSCREEN | SDL_WINDOW_INPUT_GRABBED );
		else
			SetBits( wndFlags, SDL_WINDOW_FULLSCREEN_DESKTOP );
		SetBits( wndFlags, SDL_WINDOW_BORDERLESS );
		xpos = ypos = 0;
	}
#else
	SetBits( wndFlags, SDL_WINDOW_FULLSCREEN | SDL_WINDOW_FULLSCREEN_DESKTOP | SDL_WINDOW_INPUT_GRABBED );
	xpos = ypos = SDL_WINDOWPOS_UNDEFINED;
#endif

	if( !VID_CreateWindowWithSafeGL( wndname, xpos, ypos, width, height, wndFlags ))
		return false;

	// update window size if it was maximized, just in case
	if( FBitSet( SDL_GetWindowFlags( host.hWnd ), SDL_WINDOW_MAXIMIZED|SDL_WINDOW_FULLSCREEN_DESKTOP ) != 0 )
		SDL_GetWindowSize( host.hWnd, &width, &height );

#if !XASH_MOBILE_PLATFORM
	if( window_mode != WINDOW_MODE_WINDOWED )
	{
		if( !VID_SetScreenResolution( width, height, window_mode ))
			return false;
	}
	else VID_RestoreScreenResolution();
#endif

	SDL_ShowWindow( host.hWnd );

	if( glw_state.software )
	{
		int sdl_renderer = -2;
		char cmd[64];

		if( Sys_GetParmFromCmdLine("-sdl_renderer", cmd ) )
			sdl_renderer = Q_atoi( cmd );

		if( sdl_renderer >= -1 )
		{
			sw.renderer = SDL_CreateRenderer( host.hWnd, sdl_renderer, 0 );
			if( !sw.renderer )
				Con_Printf( S_ERROR "failed to create SDL renderer: %s\n", SDL_GetError() );
			else
			{
				SDL_RendererInfo info;
				SDL_GetRendererInfo( sw.renderer, &info );
				Con_Printf( "SDL_Renderer %s initialized\n", info.name );
			}
		}
	}
	else
	{
		if( !glw_state.initialized )
		{
			while( !GL_CreateContext( ))
			{
				glw_state.safe++;
				if(glw_state.safe > SAFE_DONTCARE)
					return false;
				GL_SetupAttributes(); // re-choose attributes
			}

			VID_StartupGamma();
		}

		if( !GL_UpdateContext( ))
		return false;

	}

#else // SDL_VERSION_ATLEAST( 2, 0, 0 )
	Uint32 flags = 0;

	if( window_mode != WINDOW_MODE_WINDOWED )
		SetBits( flags, SDL_FULLSCREEN|SDL_HWSURFACE );

	if( !glw_state.software )
		SetBits( flags, SDL_OPENGL );

	if( !VID_CreateWindowWithSafeGL( wndname, xpos, ypos, width, height, wndFlags ))
		return false;
#endif // SDL_VERSION_ATLEAST( 2, 0, 0 )

	VID_SaveWindowSize( width, height, maximized );

	return true;
}

/*
=================
VID_DestroyWindow
=================
*/
void VID_DestroyWindow( void )
{
	GL_DeleteContext();

	VID_RestoreScreenResolution();
	if( host.hWnd )
	{
#if SDL_VERSION_ATLEAST( 2, 0, 0 )
		SDL_DestroyWindow ( host.hWnd );
#endif // SDL_VERSION_ATLEAST( 2, 0, 0 )
		host.hWnd = NULL;
	}

	if( refState.fullScreen )
	{
		refState.fullScreen = false;
	}
}

/*
==================
GL_SetupAttributes
==================
*/
static void GL_SetupAttributes( void )
{
#if SDL_VERSION_ATLEAST( 2, 0, 0 )
	SDL_GL_ResetAttributes();
#endif // SDL_VERSION_ATLEAST( 2, 0, 0 )

	ref.dllFuncs.GL_SetupAttributes( glw_state.safe );
}

void GL_SwapBuffers( void )
{
#if SDL_VERSION_ATLEAST( 2, 0, 0 )
	SDL_GL_SwapWindow( host.hWnd );
#else // SDL_VERSION_ATLEAST( 2, 0, 0 )
	SDL_Flip( host.hWnd );
#endif // SDL_VERSION_ATLEAST( 2, 0, 0 )
}

int GL_SetAttribute( int attr, int val )
{
	switch( attr )
	{
#define MAP_REF_API_ATTRIBUTE_TO_SDL( name ) case REF_##name: return SDL_GL_SetAttribute( SDL_##name, val );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_RED_SIZE );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_GREEN_SIZE );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_BLUE_SIZE );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_ALPHA_SIZE );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_DOUBLEBUFFER );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_DEPTH_SIZE );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_STENCIL_SIZE );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_MULTISAMPLEBUFFERS );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_MULTISAMPLESAMPLES );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_ACCELERATED_VISUAL );
#if SDL_VERSION_ATLEAST( 2, 0, 0 )
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_CONTEXT_MAJOR_VERSION );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_CONTEXT_MINOR_VERSION );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_CONTEXT_EGL );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_CONTEXT_FLAGS );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_SHARE_WITH_CURRENT_CONTEXT );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_FRAMEBUFFER_SRGB_CAPABLE );
	case REF_GL_CONTEXT_PROFILE_MASK:
#ifdef SDL_HINT_OPENGL_ES_DRIVER
		if( val == REF_GL_CONTEXT_PROFILE_ES )
		{
			SDL_SetHint(SDL_HINT_OPENGL_ES_DRIVER, "1");
			SDL_SetHint( "SDL_VIDEO_X11_FORCE_EGL", "1" );
		}
#endif // SDL_HINT_OPENGL_ES_DRIVER
		return SDL_GL_SetAttribute( SDL_GL_CONTEXT_PROFILE_MASK, val );
#endif
#if SDL_VERSION_ATLEAST( 2, 0, 4 )
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_CONTEXT_RELEASE_BEHAVIOR );
#endif
#if SDL_VERSION_ATLEAST( 2, 0, 6 )
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_CONTEXT_RESET_NOTIFICATION );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_CONTEXT_NO_ERROR );
#endif
#undef MAP_REF_API_ATTRIBUTE_TO_SDL
	}

	return -1;
}

int GL_GetAttribute( int attr, int *val )
{
	switch( attr )
	{
#define MAP_REF_API_ATTRIBUTE_TO_SDL( name ) case REF_##name: return SDL_GL_GetAttribute( SDL_##name, val );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_RED_SIZE );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_GREEN_SIZE );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_BLUE_SIZE );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_ALPHA_SIZE );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_DOUBLEBUFFER );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_DEPTH_SIZE );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_STENCIL_SIZE );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_MULTISAMPLEBUFFERS );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_MULTISAMPLESAMPLES );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_ACCELERATED_VISUAL );
#if SDL_VERSION_ATLEAST( 2, 0, 0 )
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_CONTEXT_MAJOR_VERSION );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_CONTEXT_MINOR_VERSION );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_CONTEXT_EGL );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_CONTEXT_FLAGS );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_SHARE_WITH_CURRENT_CONTEXT );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_FRAMEBUFFER_SRGB_CAPABLE );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_CONTEXT_PROFILE_MASK );
#endif
#if SDL_VERSION_ATLEAST( 2, 0, 4 )
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_CONTEXT_RELEASE_BEHAVIOR );
#endif
#if SDL_VERSION_ATLEAST( 2, 0, 6 )
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_CONTEXT_RESET_NOTIFICATION );
		MAP_REF_API_ATTRIBUTE_TO_SDL( GL_CONTEXT_NO_ERROR );
#endif
#undef MAP_REF_API_ATTRIBUTE_TO_SDL
	}

	return 0;
}

#ifndef EGL_LIB
#define EGL_LIB NULL
#endif

/*
==================
R_Init_Video
==================
*/
qboolean R_Init_Video( const int type )
{
	string safe;
	qboolean retval;
#if SDL_VERSION_ATLEAST( 2, 0, 0 )
	SDL_DisplayMode displayMode;
	SDL_GetCurrentDisplayMode(0, &displayMode);
	refState.desktopBitsPixel = SDL_BITSPERPIXEL( displayMode.format );
#else
	refState.desktopBitsPixel = 16;
#endif

#ifdef SDL_HINT_QTWAYLAND_WINDOW_FLAGS
	SDL_SetHint( SDL_HINT_QTWAYLAND_WINDOW_FLAGS, "OverridesSystemGestures" );
#endif
#ifdef SDL_HINT_QTWAYLAND_CONTENT_ORIENTATION
	SDL_SetHint( SDL_HINT_QTWAYLAND_CONTENT_ORIENTATION, "landscape" );
#endif

#if SDL_VERSION_ATLEAST( 2, 0, 0 ) && !XASH_WIN32
	SDL_SetHint( "SDL_VIDEO_X11_XRANDR", "1" );
	SDL_SetHint( "SDL_VIDEO_X11_XVIDMODE", "1" );
	if( Sys_CheckParm( "-egl" ) )
		SDL_SetHint( "SDL_VIDEO_X11_FORCE_EGL", "1" );
#endif

	// must be initialized before creating window
#if XASH_WIN32
	WIN_SetDPIAwareness();
#endif

	switch( type )
	{
	case REF_SOFTWARE:
		glw_state.software = true;
		break;
	case REF_GL:
		if( !glw_state.safe && Sys_GetParmFromCmdLine( "-safegl", safe ) )
			glw_state.safe = bound( SAFE_NO, Q_atoi( safe ), SAFE_DONTCARE );

		// refdll can request some attributes
		GL_SetupAttributes( );

		if( SDL_GL_LoadLibrary( EGL_LIB ) )
		{
			Con_Reportf( S_ERROR  "Couldn't initialize OpenGL: %s\n", SDL_GetError());
			return false;
		}
		break;
	default:
		Host_Error( "Can't initialize unknown context type %d!\n", type );
		break;
	}

	if( !(retval = VID_SetMode()) )
	{
		return retval;
	}

	switch( type )
	{
	case REF_GL:
		// refdll also can check extensions
		ref.dllFuncs.GL_InitExtensions();
		break;
	case REF_SOFTWARE:
	default:
		break;
	}

	R_InitVideoModes();

	host.renderinfo_changed = false;

	return true;
}

rserr_t R_ChangeDisplaySettings( int width, int height, window_mode_t window_mode )
{
#if SDL_VERSION_ATLEAST( 2, 0, 0 )
	SDL_DisplayMode displayMode;

	SDL_GetCurrentDisplayMode( 0, &displayMode );

	// check our desktop attributes
	refState.desktopBitsPixel = SDL_BITSPERPIXEL( displayMode.format );
	if( window_mode == WINDOW_MODE_BORDERLESS )
	{
		width = displayMode.w;
		height = displayMode.h;
	}
#endif

	refState.fullScreen = window_mode != WINDOW_MODE_WINDOWED;
	Con_Reportf( "R_ChangeDisplaySettings: Setting video mode to %dx%d %s\n", width, height, refState.fullScreen ? "fullscreen" : "windowed" );

	if( !host.hWnd )
	{
		if( !VID_CreateWindow( width, height, window_mode ))
			return rserr_invalid_mode;
	}
	else if( refState.fullScreen )
	{
		if( !VID_SetScreenResolution( width, height, window_mode ))
			return rserr_invalid_fullscreen;
	}
	else
	{
		VID_RestoreScreenResolution();

#if SDL_VERSION_ATLEAST( 2, 0, 0 )
		if( SDL_SetWindowFullscreen( host.hWnd, 0 ))
			return rserr_invalid_fullscreen;
#if SDL_VERSION_ATLEAST( 2, 0, 5 )
		SDL_SetWindowResizable( host.hWnd, SDL_TRUE );
#endif
		SDL_SetWindowBordered( host.hWnd, SDL_TRUE );
		SDL_SetWindowSize( host.hWnd, width, height );
#endif // SDL_VERSION_ATLEAST( 2, 0, 0 )

		VID_SaveWindowSize( width, height, true );
	}

	return rserr_ok;
}

/*
==================
VID_SetMode

Set the described video mode
==================
*/
qboolean VID_SetMode( void )
{
	int iScreenWidth, iScreenHeight;
	rserr_t	err;
	window_mode_t window_mode;

	iScreenWidth = Cvar_VariableInteger( "width" );
	iScreenHeight = Cvar_VariableInteger( "height" );

	if( iScreenWidth < VID_MIN_WIDTH ||
		iScreenHeight < VID_MIN_HEIGHT )	// trying to get resolution automatically by default
	{
#if SDL_VERSION_ATLEAST( 2, 0, 0 )
#if !defined( DEFAULT_MODE_WIDTH ) || !defined( DEFAULT_MODE_HEIGHT )
		SDL_DisplayMode mode;

		SDL_GetDesktopDisplayMode( 0, &mode );

		iScreenWidth = mode.w;
		iScreenHeight = mode.h;
#else
		iScreenWidth = DEFAULT_MODE_WIDTH;
		iScreenHeight = DEFAULT_MODE_HEIGHT;
#endif
#else // SDL_VERSION_ATLEAST( 2, 0, 0 )
		iScreenWidth = 320;
		iScreenHeight = 240;
#endif // SDL_VERSION_ATLEAST( 2, 0, 0 )
	}

	if( !FBitSet( vid_fullscreen.flags, FCVAR_CHANGED ))
		Cvar_DirectSet( &vid_fullscreen, DEFAULT_FULLSCREEN );
	else
		ClearBits( vid_fullscreen.flags, FCVAR_CHANGED );

	SetBits( gl_vsync.flags, FCVAR_CHANGED );

	window_mode = bound( 0, vid_fullscreen.value, WINDOW_MODE_COUNT - 1 );

	if(( err = R_ChangeDisplaySettings( iScreenWidth, iScreenHeight, window_mode )) == rserr_ok )
	{
		sdlState.prev_width = iScreenWidth;
		sdlState.prev_height = iScreenHeight;
	}
	else
	{
		if( err == rserr_invalid_fullscreen )
		{
			Cvar_DirectSet( &vid_fullscreen, "0" );
			Con_Reportf( S_ERROR  "VID_SetMode: fullscreen unavailable in this mode\n" );
			Sys_Warn("fullscreen unavailable in this mode!");
			if(( err = R_ChangeDisplaySettings( iScreenWidth, iScreenHeight, WINDOW_MODE_WINDOWED )) == rserr_ok )
				return true;
		}
		else if( err == rserr_invalid_mode )
		{
			Con_Reportf( S_ERROR  "VID_SetMode: invalid mode\n" );
			Sys_Warn( "invalid mode, engine will run in %dx%d", sdlState.prev_width, sdlState.prev_height );
		}

		// try setting it back to something safe
		if(( err = R_ChangeDisplaySettings( sdlState.prev_width, sdlState.prev_height, WINDOW_MODE_WINDOWED )) != rserr_ok )
		{
			Con_Reportf( S_ERROR "VID_SetMode: could not revert to safe mode\n" );
			Sys_Warn("could not revert to safe mode!");
			return false;
		}
	}

	return true;
}

/*
==================
R_Free_Video
==================
*/
void R_Free_Video( void )
{
	GL_DeleteContext ();

	VID_DestroyWindow ();

	R_FreeVideoModes();

	ref.dllFuncs.GL_ClearExtensions();

#if SDL_VERSION_ATLEAST( 2, 0, 0 )
	SDL_VideoQuit();
#endif
}

#endif // XASH_DEDICATED