/*

 SDL - Simple DirectMedia Layer

 Copyright (C) 1997-2009 Sam Lantinga

 This library is free software; you can redistribute it and/or

 modify it under the terms of the GNU Lesser General Public

 License as published by the Free Software Foundation; either

 version 2.1 of the License, or (at your option) any later version.

 This library 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

 Lesser General Public License for more details.

 You should have received a copy of the GNU Lesser General Public

 License along with this library; if not, write to the Free Software

 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

 Sam Lantinga

 slouken@libsdl.org

 */

#include "SDL_uikitopengles.h"

#include "SDL_uikitopenglview.h"

#include "SDL_uikitappdelegate.h"

#include "SDL_uikitwindow.h"

#include "jumphack.h"

#include "SDL_sysvideo.h"

#include "SDL_loadso.h"

#include <dlfcn.h>

static int UIKit_GL_Initialize(_THIS);

void *

UIKit_GL_GetProcAddress(_THIS, const char *proc) {	

	/* Look through all SO's for the proc symbol.  Here's why:

	 -Looking for the path to the OpenGL Library seems not to work in the iPhone Simulator.

	 -We don't know that the path won't change in the future.

	 */

	return SDL_LoadFunction(RTLD_DEFAULT, proc);

}

/*

 note that SDL_GL_Delete context makes it current without passing the window

 */

int UIKit_GL_MakeCurrent(_THIS, SDL_Window * window, SDL_GLContext context) {

	if (context) {

		SDL_WindowData *data = (SDL_WindowData *)window->driverdata;

		[data->view setCurrentContext];

	}

	else {

		[EAGLContext setCurrentContext: nil];

	}

	return 0;

}

int UIKit_GL_LoadLibrary(_THIS, const char *path) {

	/* 

	 shouldn't be passing a path into this function 

	 why?  Because we've already loaded the library

	 and because the SDK forbids loading an external SO

	 */

	if (path != NULL) {

		SDL_SetError("iPhone GL Load Library just here for compatibility");

		return -1;

	}

	return 0;

}

void UIKit_GL_SwapWindow(_THIS, SDL_Window * window) {

	SDL_WindowData *data = (SDL_WindowData *)window->driverdata;

	if (nil == data->view) {

		return;

	}

	[data->view swapBuffers];

	/* since now we've got something to draw

	 make the window visible */

	[data->uiwindow makeKeyAndVisible];

	/* we need to let the event cycle run, or the OS won't update the OpenGL view! */

	SDL_PumpEvents();

}

SDL_GLContext UIKit_GL_CreateContext(_THIS, SDL_Window * window) {

	SDL_uikitopenglview *view;

	SDL_WindowData *data = (SDL_WindowData *)window->driverdata;

	/* construct our view, passing in SDL's OpenGL configuration data */

	view = [[SDL_uikitopenglview alloc] initWithFrame: [[UIScreen mainScreen] applicationFrame] \

					    retainBacking: _this->gl_config.retained_backing \

						    rBits: _this->gl_config.red_size \

						    gBits: _this->gl_config.green_size \

						    bBits: _this->gl_config.blue_size \

						    aBits: _this->gl_config.alpha_size \

						depthBits: _this->gl_config.depth_size ];

	data->view = view;

	view.tag = 54321;

	// rotate view

	[view setTransform:CGAffineTransformMakeRotation(M_PI/2.0f)];

	/* add the view to our window */

	[data->uiwindow addSubview: view];

	/* Don't worry, the window retained the view */

	[view release];

	if ( UIKit_GL_MakeCurrent(_this, window, view) < 0 ) {

		UIKit_GL_DeleteContext(_this, view);

		return NULL;

	}

	return view;

}

void UIKit_GL_DeleteContext(_THIS, SDL_GLContext context) {

	/* the delegate has retained the view, this will release him */

	SDL_uikitopenglview *view = (SDL_uikitopenglview *)context;

	/* this will also delete it */

	[view removeFromSuperview];

	return;

}