/*
 *	Copyright (C) 2007-2012 Gabest
 *	http://www.gabest.org
 *
 *  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 2, 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.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with GNU Make; see the file COPYING.  If not, write to
 *  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA USA.
 *  http://www.gnu.org/copyleft/gpl.html
 *
 */

#include "GSWndOGL.h"

#ifdef _LINUX
GSWndOGL::GSWndOGL()
	: m_NativeWindow(0), m_NativeDisplay(NULL), m_swapinterval(NULL)
{
}

bool GSWndOGL::CreateContext(int major, int minor)
{
	if ( !m_NativeDisplay || !m_NativeWindow )
	{
		fprintf( stderr, "Wrong X11 display/window\n" );
		exit(1);
	}

	// Get visual information
	static int attrListDbl[] =
	{
		// GLX_X_RENDERABLE: If True is specified, then only frame buffer configurations that have associated X
		// visuals (and can be used to render to Windows and/or GLX pixmaps) will be considered. The default value is GLX_DONT_CARE.
		GLX_X_RENDERABLE    , True,
		GLX_RED_SIZE        , 8,
		GLX_GREEN_SIZE      , 8,
		GLX_BLUE_SIZE       , 8,
		GLX_DEPTH_SIZE      , 24,
		GLX_DOUBLEBUFFER    , True,
		None
	};

	PFNGLXCHOOSEFBCONFIGPROC glXChooseFBConfig = (PFNGLXCHOOSEFBCONFIGPROC) glXGetProcAddress((GLubyte *) "glXChooseFBConfig");
	int fbcount = 0;
	GLXFBConfig *fbc = glXChooseFBConfig(m_NativeDisplay, DefaultScreen(m_NativeDisplay), attrListDbl, &fbcount);
	if (!fbc || fbcount < 1) return false;

	PFNGLXCREATECONTEXTATTRIBSARBPROC glXCreateContextAttribsARB = (PFNGLXCREATECONTEXTATTRIBSARBPROC)glXGetProcAddress((const GLubyte*) "glXCreateContextAttribsARB");
	if (!glXCreateContextAttribsARB) return false;

	// Create a context
	int context_attribs[] =
	{
		GLX_CONTEXT_MAJOR_VERSION_ARB, major,
		GLX_CONTEXT_MINOR_VERSION_ARB, minor,
		// FIXME : Request a debug context to ease opengl development
		// Note: don't support deprecated feature (pre openg 3.1)
		//GLX_CONTEXT_FLAGS_ARB, GLX_CONTEXT_DEBUG_BIT_ARB | GLX_CONTEXT_FORWARD_COMPATIBLE_BIT_ARB,
		GLX_CONTEXT_FLAGS_ARB, GLX_CONTEXT_DEBUG_BIT_ARB,
		None
	};

	m_context = glXCreateContextAttribsARB(m_NativeDisplay, fbc[0], 0, true, context_attribs);
	if (!m_context) return false;

	XSync( m_NativeDisplay, false);
	return true;
}

void GSWndOGL::AttachContext()
{
	if (!IsContextAttached()) {
		//fprintf(stderr, "Attach the context\n");
		glXMakeCurrent(m_NativeDisplay, m_NativeWindow, m_context);
		m_ctx_attached = true;
	}
}

void GSWndOGL::DetachContext()
{
	if (IsContextAttached()) {
		//fprintf(stderr, "Detach the context\n");
		glXMakeCurrent(m_NativeDisplay, None, NULL);
		m_ctx_attached = false;
	}
}

void GSWndOGL::CheckContext()
{
	int glxMajorVersion, glxMinorVersion;
	glXQueryVersion(m_NativeDisplay, &glxMajorVersion, &glxMinorVersion);
	if (glXIsDirect(m_NativeDisplay, m_context))
		fprintf(stderr, "glX-Version %d.%d with Direct Rendering\n", glxMajorVersion, glxMinorVersion);
	else
		fprintf(stderr, "glX-Version %d.%d with Indirect Rendering !!! It won't support properly opengl\n", glxMajorVersion, glxMinorVersion);
}

bool GSWndOGL::Attach(void* handle, bool managed)
{
	m_NativeWindow = *(Window*)handle;
	m_managed = managed;

	m_NativeDisplay = XOpenDisplay(NULL);

	// Note: 4.2 crash on latest nvidia drivers!
	if (!CreateContext(3, 3)) return false;

	AttachContext();

	CheckContext();

	m_swapinterval = (PFNGLXSWAPINTERVALMESAPROC)glXGetProcAddress((const GLubyte*) "glXSwapIntervalMESA");
	//PFNGLXSWAPINTERVALMESAPROC m_swapinterval = (PFNGLXSWAPINTERVALMESAPROC)glXGetProcAddress((const GLubyte*) "glXSwapInterval");


	return true;
}

void GSWndOGL::Detach()
{
	// Actually the destructor is not called when there is only a GSclose/GSshutdown
	// The window still need to be closed
	DetachContext();
	if (m_context) glXDestroyContext(m_NativeDisplay, m_context);

	if (m_NativeDisplay) {
		XCloseDisplay(m_NativeDisplay);
		m_NativeDisplay = NULL;
	}
}

bool GSWndOGL::Create(const string& title, int w, int h)
{
	if(m_NativeWindow) return false;

	if(w <= 0 || h <= 0) {
		w = theApp.GetConfig("ModeWidth", 640);
		h = theApp.GetConfig("ModeHeight", 480);
	}

	m_managed = true;

	// note this part must be only executed when replaying .gs debug file
	m_NativeDisplay = XOpenDisplay(NULL);

	int attrListDbl[] = { GLX_RGBA, GLX_DOUBLEBUFFER,
		GLX_RED_SIZE, 8,
		GLX_GREEN_SIZE, 8,
		GLX_BLUE_SIZE, 8,
		GLX_DEPTH_SIZE, 24,
		None
	};
	XVisualInfo* vi = glXChooseVisual(m_NativeDisplay, DefaultScreen(m_NativeDisplay), attrListDbl);

	/* create a color map */
	XSetWindowAttributes attr;
	attr.colormap = XCreateColormap(m_NativeDisplay, RootWindow(m_NativeDisplay, vi->screen),
			vi->visual, AllocNone);
	attr.border_pixel = 0;
	attr.event_mask = ExposureMask | KeyPressMask | KeyReleaseMask | ButtonPressMask |
		StructureNotifyMask | SubstructureRedirectMask | SubstructureNotifyMask |
		EnterWindowMask | LeaveWindowMask | FocusChangeMask ;

	// Create a window at the last position/size
	m_NativeWindow = XCreateWindow(m_NativeDisplay, RootWindow(m_NativeDisplay, vi->screen),
			0 , 0 , w, h, 0, vi->depth, InputOutput, vi->visual,
			CWBorderPixel | CWColormap | CWEventMask, &attr);

	XMapWindow (m_NativeDisplay, m_NativeWindow);
	XFree(vi);

	if (!CreateContext(3, 3)) return false;

	AttachContext();

	return (m_NativeWindow != 0);
}

void* GSWndOGL::GetDisplay()
{
	// note this part must be only executed when replaying .gs debug file
	return (void*)m_NativeDisplay;
}

GSVector4i GSWndOGL::GetClientRect()
{
	unsigned int h = 480;
	unsigned int w = 640;

	unsigned int borderDummy;
	unsigned int depthDummy;
	Window winDummy;
    int xDummy;
    int yDummy;

	if (!m_NativeDisplay) m_NativeDisplay = XOpenDisplay(NULL);
	XGetGeometry(m_NativeDisplay, m_NativeWindow, &winDummy, &xDummy, &yDummy, &w, &h, &borderDummy, &depthDummy);

	return GSVector4i(0, 0, (int)w, (int)h);
}

// Returns FALSE if the window has no title, or if th window title is under the strict
// management of the emulator.

bool GSWndOGL::SetWindowText(const char* title)
{
	if (!m_managed) return true;

	XTextProperty prop;

	memset(&prop, 0, sizeof(prop));

	char* ptitle = (char*)title;
	if (XStringListToTextProperty(&ptitle, 1, &prop)) {
		XSetWMName(m_NativeDisplay, m_NativeWindow, &prop);
	}

	XFree(prop.value);
	XFlush(m_NativeDisplay);

	return true;
}

void GSWndOGL::SetVSync(bool enable)
{
	// m_swapinterval uses an integer as parameter
	// 0 -> disable vsync
	// n -> wait n frame
	if (m_swapinterval) m_swapinterval((int)enable);
}

void GSWndOGL::Flip()
{
	glXSwapBuffers(m_NativeDisplay, m_NativeWindow);
}

void GSWndOGL::Show()
{
	XMapRaised(m_NativeDisplay, m_NativeWindow);
	XFlush(m_NativeDisplay);
}

void GSWndOGL::Hide()
{
	XUnmapWindow(m_NativeDisplay, m_NativeWindow);
	XFlush(m_NativeDisplay);
}

void GSWndOGL::HideFrame()
{
	// TODO
}

#endif