/* 
 * Copyright (c) 2002 Light Weight Java Game Library Project
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are 
 * met:
 * 
 * * Redistributions of source code must retain the above copyright 
 *   notice, this list of conditions and the following disclaimer.
 *
 * * Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 *
 * * Neither the name of 'Light Weight Java Game Library' nor the names of 
 *   its contributors may be used to endorse or promote products derived 
 *   from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR 
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
/**
 * $Id$
 *
 * Base Win32 functionality for GL.
 *
 * @author cix_foo <cix_foo@users.sourceforge.net>
 * @version $Revision$
 */

#include <windows.h>
#include "org_lwjgl_opengl_BaseGL.h"
#include "extgl.h"
#include "Window.h"
#include "jni.h"

HGLRC			hglrc = NULL;						// OpenGL rendering context

static int findPixelFormat(JNIEnv *env, unsigned int flags, int bpp, int alpha, int depth, int stencil) {
	PIXELFORMATDESCRIPTOR pfd = { 
		sizeof(PIXELFORMATDESCRIPTOR),   // size of this pfd 
		1,                     // version number 
		flags,         // RGBA type 
		PFD_TYPE_RGBA,
		(BYTE)bpp,       
		0, 0, 0, 0, 0, 0,      // color bits ignored 
		(BYTE)alpha,       
		0,                     // shift bit ignored 
		0,                     // no accumulation buffer 
		0, 0, 0, 0,            // accum bits ignored 
		(BYTE)depth,       
		(BYTE)stencil,     
		0,                     // No auxiliary buffer 
		PFD_MAIN_PLANE,        // main layer
		0,                     // reserved 
		0, 0, 0                // layer masks ignored
	};

	// get the best available match of pixel format for the device context  
	int iPixelFormat = ChoosePixelFormat(hdc, &pfd);
	if (iPixelFormat == 0) {
		throwException(env, "Failed to choose pixel format");
		return -1;
	}

#ifdef _DEBUG
	printf("Pixel format is %d\n", iPixelFormat);
#endif

	// make that the pixel format of the device context 
	if (SetPixelFormat(hdc, iPixelFormat, &pfd) == FALSE) {
		printf("Failed to set pixel format\n");
		throwException(env, "Failed to choose pixel format");
		return -1;
	}

	// 3. Check the chosen format matches or exceeds our specifications
	PIXELFORMATDESCRIPTOR desc;
	if (DescribePixelFormat(hdc, iPixelFormat, sizeof(PIXELFORMATDESCRIPTOR), &desc) == 0) {
		throwException(env, "Could not describe pixel format");
		return -1;
	}

	if (desc.cColorBits < bpp) {
		throwException(env, "This application requires a greater colour depth");
		return -1;
	}

	if (desc.cAlphaBits < alpha) {
		throwException(env, "This application requires a greater alpha depth");
		return -1;
	}

	if (desc.cStencilBits < stencil) {
		throwException(env, "This application requires a greater stencil depth");
		return -1;
	}

	if (desc.cDepthBits < depth) {
		throwException(env, "This application requires a greater depth buffer depth");
		return -1;
	}

	if ((desc.dwFlags & PFD_GENERIC_FORMAT) != 0 || (desc.dwFlags & PFD_GENERIC_ACCELERATED) != 0) {
		throwException(env, "Mode not supported by hardware");
		return -1;
	}

	if ((desc.dwFlags & flags) != flags) {
		throwException(env, "Capabilities not supported");
		return -1;
	}

	// 4. Initialise other things now
	if (extgl_Open() != 0) {
		throwException(env, "Failed to open extgl");
		return -1;
	}
	return iPixelFormat;
}

/*
 * Class:     org_lwjgl_opengl_BaseGL
 * Method:    nCreate
 * Signature: (Ljava/lang/String;IIIIIIIIZ)V
 */
JNIEXPORT void JNICALL Java_org_lwjgl_opengl_BaseGL_nCreate
  (JNIEnv * env, jobject obj, 
	jstring title, jint x, jint y, jint width, jint height, jint bpp, jint alpha, jint depth, jint stencil, jboolean fullscreen)
{

	// 1. Create a window
	const char * titleString = env->GetStringUTFChars(title, NULL);
	if (!createWindow(titleString, x, y, width, height, fullscreen == JNI_TRUE ? true : false)) {
		env->ReleaseStringUTFChars((jstring) title, titleString);
		closeWindow();
		throwException(env, "Failed to create the window.");
		return;
	}
	env->ReleaseStringUTFChars(title, titleString);


	// 2. Choose a pixel format and set it
	unsigned int flags = PFD_DRAW_TO_WINDOW |   // support window 
		PFD_SUPPORT_OPENGL |   // support OpenGL 
		PFD_DOUBLEBUFFER;      // double buffered 

	int iPixelFormat = findPixelFormat(env, flags, bpp, alpha, depth, stencil);
	if (iPixelFormat == -1) {
		closeWindow();
		return;
	}
	// Create a rendering context
	hglrc = wglCreateContext(hdc);
	if (hglrc == NULL) {
		throwException(env, "Failed to create OpenGL rendering context");
		closeWindow();
		return;
	}

	// Automatically make it the current context
	wglMakeCurrent(hdc, hglrc);

	// Initialise GL extensions
	if (extgl_Initialize() != 0) {
		closeWindow();
		throwException(env, "Failed to initialize GL extensions");
		return;
	}

	// Stash handle back in Java
	env->SetIntField(obj, env->GetFieldID(env->GetObjectClass(obj), "handle", "I"), (jint) hglrc);

}

/*
 * Class:     org_lwjgl_opengl_BaseGL
 * Method:    nDestroy
 * Signature: ()V
 */
JNIEXPORT void JNICALL Java_org_lwjgl_opengl_BaseGL_nDestroyGL
  (JNIEnv * env, jobject obj)
{
	wglMakeCurrent(NULL, NULL);

	// Delete the rendering context
	if (hglrc != NULL) {
#ifdef _DEBUG
		printf("Delete GL context\n");
#endif
		wglDeleteContext(hglrc); 
		hglrc = NULL;
	}
	closeWindow();
	extgl_Close();
}

/*
 * Class:     org_lwjgl_opengl_BaseGL
 * Method:    swapBuffers
 * Signature: ()V
 */
JNIEXPORT void JNICALL Java_org_lwjgl_opengl_BaseGL_swapBuffers
  (JNIEnv *, jobject) 
{
	wglSwapLayerBuffers(hdc, WGL_SWAP_MAIN_PLANE);
}