/*
 * 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.
 */

/**
 * $Id$
 *
 * Linux specific library for display handling.
 *
 * @author elias_naur <elias_naur@users.sourceforge.net>
 * @version $Revision$
 */


#include "extgl.h"
#include <X11/X.h>
#include <X11/Xlib.h>
#include <X11/extensions/xf86vmode.h>
#include <X11/Xutil.h>
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <jni.h>
#include "org_lwjgl_Display.h"

static int saved_width;
static int saved_height;

static int getDisplayModes(Display *disp, int screen, int *num_modes, XF86VidModeModeInfo ***avail_modes) {
	int event_base, error_base, xvid_ver, xvid_rev;
	
	if (!XF86VidModeQueryExtension(disp, &event_base, &error_base)) {
#ifdef _DEBUG
		printf("XF86VidMode extension not available\n");
#endif
		return 0;
	}
	XF86VidModeQueryVersion(disp, &xvid_ver, &xvid_rev);
#ifdef _DEBUG
	printf("XF86VidMode extension version %i.%i\n", xvid_ver, xvid_rev);
#endif
	XF86VidModeGetAllModeLines(disp, screen, num_modes, avail_modes);
	return 1;
}

static bool setMode(int width, int height, bool lock_mode) {
        int num_modes, i;
        XF86VidModeModeInfo **avail_modes;
	int screen;
	Display *disp = XOpenDisplay(NULL);

	if (disp == NULL) {
#ifdef _DEBUG
		printf("Could not open X connection\n");
#endif
		return false;
	}
	screen = DefaultScreen(disp);
	if (!getDisplayModes(disp, screen, &num_modes, &avail_modes)) {
		XCloseDisplay(disp);
#ifdef _DEBUG
		printf("Could not get display modes\n");
#endif
		return false;
	}
	XF86VidModeLockModeSwitch(disp, screen, 0);
	for ( i = 0; i < num_modes; ++i ) {
#ifdef _DEBUG
		printf("Mode %d: %dx%d\n", i, avail_modes[i]->hdisplay, avail_modes[i]->vdisplay);
#endif
		if (avail_modes[i]->hdisplay == width && avail_modes[i]->vdisplay == height) {
			if (!XF86VidModeSwitchToMode(disp, screen, avail_modes[i])) {
#ifdef _DEBUG
				printf("Could not switch mode\n");
#endif
				break;
			}
//			XF86VidModeSetViewPort(disp, screen, 0, 0);
			if (lock_mode)
				XF86VidModeLockModeSwitch(disp, screen, 1);
			XFree(avail_modes);
			XCloseDisplay(disp);
			return true;
		}
	}
	XFree(avail_modes);
	XCloseDisplay(disp);
	return false;
}

JNIEXPORT void JNICALL Java_org_lwjgl_Display_init
  (JNIEnv * env, jclass clazz)
{
        int num_modes;
        XF86VidModeModeInfo **avail_modes;
	int screen;
	Display *disp = XOpenDisplay(NULL);
        if (disp == NULL) {
#ifdef _DEBUG
                printf("Could not open X connection\n");
#endif
		return;
        }
	screen = DefaultScreen(disp);
	
	if (!getDisplayModes(disp, screen, &num_modes, &avail_modes)) {
#ifdef _DEBUG
		printf("Could not get display modes\n");
#endif
	}
	saved_width = avail_modes[0]->hdisplay;
	saved_height = avail_modes[0]->vdisplay;
	int bpp = XDefaultDepth(disp, screen);
#ifdef _DEBUG
	printf("Saved width, height %d, %d\n", saved_width, saved_height);
#endif
	jclass jclass_DisplayMode = env->FindClass("org/lwjgl/DisplayMode");
	jmethodID ctor = env->GetMethodID(jclass_DisplayMode, "<init>", "(IIII)V");
	jobject newMode = env->NewObject(jclass_DisplayMode, ctor, saved_width, saved_height, bpp, 0);
	jfieldID fid_initialMode = env->GetStaticFieldID(clazz, "mode", "Lorg/lwjgl/DisplayMode;");
	env->SetStaticObjectField(clazz, fid_initialMode, newMode);

	XFree(avail_modes);
	XCloseDisplay(disp);
}

JNIEXPORT void JNICALL Java_org_lwjgl_Display_setDisplayMode(JNIEnv * env, jclass clazz, jobject mode) {
	jclass cls_displayMode = env->FindClass("org/lwjgl/DisplayMode");
	jfieldID fid_width = env->GetFieldID(cls_displayMode, "width", "I");
	jfieldID fid_height = env->GetFieldID(cls_displayMode, "height", "I");
	int width = env->GetIntField(mode, fid_width);
	int height = env->GetIntField(mode, fid_height);
	if (setMode(width, height, true)) {
		jfieldID fid_initialMode = env->GetStaticFieldID(clazz, "mode", "Lorg/lwjgl/DisplayMode;");
		env->SetStaticObjectField(clazz, fid_initialMode, mode);
	}
}

JNIEXPORT void JNICALL Java_org_lwjgl_Display_resetDisplayMode(JNIEnv * env, jclass clazz) {
	setMode(saved_width, saved_height, false);
}

/*
 * Class:     org_lwjgl_Display
 * Method:    nGetAvailableDisplayModes
 * Signature: ()[Lorg/lwjgl/DisplayMode;
 */
JNIEXPORT jobjectArray JNICALL Java_org_lwjgl_Display_nGetAvailableDisplayModes
  (JNIEnv * env, jclass clazz)
{
	int num_modes, i;
	Display *disp = XOpenDisplay(NULL);
	int screen;
	XF86VidModeModeInfo **avail_modes;

	if (disp == NULL) {
#ifdef _DEBUG
		printf("Could not open X connection\n");
#endif
		return NULL;
	}
	
	screen = DefaultScreen(disp);
	int bpp = XDefaultDepth(disp, screen);
	
	if (!getDisplayModes(disp, screen, &num_modes, &avail_modes)) {
#ifdef _DEBUG
		printf("Could not get display modes\n");
#endif
		XCloseDisplay(disp);
		return NULL;
	}
	// Allocate an array of DisplayModes big enough
	jclass displayModeClass = env->FindClass("org/lwjgl/DisplayMode");
	jobjectArray ret = env->NewObjectArray(num_modes, displayModeClass, NULL);
	jmethodID displayModeConstructor = env->GetMethodID(displayModeClass, "<init>", "(IIII)V");
	
	for (i = 0; i < num_modes; i++) {
		jobject displayMode = env->NewObject(displayModeClass, displayModeConstructor, avail_modes[i]->hdisplay, avail_modes[i]->vdisplay, bpp, 0);
		env->SetObjectArrayElement(ret, i, displayMode);
	}
	XFree(avail_modes);
	XCloseDisplay(disp);
	return ret;
}

/*
 * Class:     org_lwjgl_Display
 * Method:    getPlatform
 * Signature: ()I
 */
JNIEXPORT jint JNICALL Java_org_lwjgl_Display_getPlatform
  (JNIEnv * env, jclass clazz)
{
	return org_lwjgl_Display_PLATFORM_GLX;
}