#include <iostream>

#include "gpudataviz.h"
#include "boring_parts.h"
#include "gtk_win_main.h"
#include "my_gtk_gl_scene.h"

// Macro to make things readable in main() function
#define EXIT_IF_FAIL(val, expr) do { \
	if ( ! (expr) ) { \
		std::cerr << "Init error " << val << std::endl; \
		exit(val); \
	} \
} while(0)

#define CALL_TRACE do { \
	std::cout << "trace " <<__PRETTY_FUNCTION__ << std::endl; \
} while(0)

int main(int argc, char* argv[]) {
	CALL_TRACE;

	int meshWidth=64, meshHeight=64; // TODO : those vars should not be hardcoded

	// Initialize GTK
	Gtk::Main gtkKit(argc, argv); // gtk itself
	Gtk::GL::init(argc, argv);    // gtkglextmm

	// Query and print OpenGL version
  int glVersionMajor, glVersionMinor;
  EXIT_IF_FAIL(1, Gdk::GL::query_version(glVersionMajor, glVersionMinor) );
  std::cout << "OpenGL extension version - " << glVersionMajor << "." << glVersionMinor << std::endl;

	// Initialize OpenGL
	Gdk::GL::ConfigMode glMode = Gdk::GL::MODE_RGB | Gdk::GL::MODE_DEPTH | Gdk::GL::MODE_DOUBLE;
	Glib::RefPtr<Gdk::GL::Config> glconfig;
	EXIT_IF_FAIL(2, glconfig=Gdk::GL::Config::create(glMode) );

	// Initialize OpenCL (if available)
	EXIT_IF_FAIL(3, initLibs()==0 ); // See boring_parts.cc

	// Initialize host work memory (array for all the vertex coordinates computed by OpenCL and displayed by OpenGL)
	cl_float4 *hostWorkMem = (cl_float4 *) calloc(meshWidth * meshHeight, sizeof(cl_float4));
	EXIT_IF_FAIL(4, hostWorkMem);

	// Initialize the OpenGL scene
	MyGTKGLScene glScene(glconfig);

	// Instantiate and run the GTK app
	GTKWinMain gtkwinmain(glScene);
	gtkKit.run(gtkwinmain);

	return 0;
}

/* MyGTKGLScene implementation
	I want to keep interesting code part in this file
		in natural reading order
*/
MyGTKGLScene::MyGTKGLScene(Glib::RefPtr<Gdk::GL::Config> &glconfig) {
	CALL_TRACE;
	set_gl_capability(glconfig); // Set OpenGL-capability to the widget.
}

MyGTKGLScene::~MyGTKGLScene() {
	CALL_TRACE;
}

void MyGTKGLScene::on_size_request(Gtk::Requisition* requisition) {
	CALL_TRACE;
  
	*requisition = Gtk::Requisition();
  requisition->width = 320; requisition->height = 240;
}

void MyGTKGLScene::on_realize() {
	CALL_TRACE; // This run once at window creation time

	Gtk::DrawingArea::on_realize();
	Glib::RefPtr<Gdk::GL::Window> glwindow = get_gl_window();

	// *** OpenGL BEGIN ***
	if (!glwindow->gl_begin(get_gl_context())) {
		std::cerr << "Oups : glwindow->gl_begin(get_gl_context())" << std::endl;
		return;
	}

	GLUquadricObj* qobj = gluNewQuadric();
	gluQuadricDrawStyle(qobj, GLU_FILL);
	glNewList(1, GL_COMPILE);
	gluSphere(qobj, 1.0, 20, 20);
	glEndList();

	static GLfloat light_diffuse[] = {1.0, 0.0, 0.0, 1.0};
	static GLfloat light_position[] = {1.0, 1.0, 1.0, 0.0};
	glLightfv(GL_LIGHT0, GL_DIFFUSE, light_diffuse);
	glLightfv(GL_LIGHT0, GL_POSITION, light_position);
	glEnable(GL_LIGHTING);
	glEnable(GL_LIGHT0);
	glEnable(GL_DEPTH_TEST);

	glClearColor(1.0, 1.0, 1.0, 1.0);
	glClearDepth(1.0);
/*
	glViewport(0, 0, get_width(), get_height());

	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	gluPerspective(40.0, 1.0, 1.0, 10.0);
	glMatrixMode(GL_MODELVIEW);
*/
	glLoadIdentity();
	gluLookAt(0.0, 0.0, 3.0,
			0.0, 0.0, 0.0,
			0.0, 1.0, 0.0);
	glTranslatef(0.0, 0.0, -3.0);

	glwindow->gl_end();
	// *** OpenGL END ***
}

bool MyGTKGLScene::on_configure_event(GdkEventConfigure* event) {
	CALL_TRACE ; // This run mainly when GTK GL Widget is resized

	Glib::RefPtr<Gdk::GL::Window> glwindow = get_gl_window();
	// *** OpenGL BEGIN ***
	if (!glwindow->gl_begin(get_gl_context())) {
		std::cerr << "Oups : glwindow->gl_begin(get_gl_context())" << std::endl;
		return false;
	}
	int width = get_width();
	int height = get_height();
	GLdouble ratio = (GLdouble) width/height;

	glViewport(0, 0, width, height);
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	gluPerspective(60.0, ratio, 0.1, 10.0);
	glMatrixMode(GL_MODELVIEW);

	glwindow->gl_end();
	// *** OpenGL END ***

	return true;
}

bool MyGTKGLScene::on_expose_event(GdkEventExpose* event) {
	CALL_TRACE ; // This run mainly when GTK GL Widget have to be redrawn

	Glib::RefPtr<Gdk::GL::Window> glwindow = get_gl_window();

	// *** OpenGL BEGIN ***
	if (!glwindow->gl_begin(get_gl_context())) {
		std::cerr << "Oups : glwindow->gl_begin(get_gl_context())" << std::endl;
		return false;
	}

	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	glCallList(1);

	glwindow->gl_end();
	// *** OpenGL END ***

	// Display the rendered image
	glwindow->swap_buffers();

	return true;
}