/* 
 * Copyright (c) 2002-2008 LWJGL 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 'LWJGL' 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: display.c 2985 2008-04-07 18:42:36Z matzon $
 *
 * Windows specific library for display handling.
 *
 * @author cix_foo <cix_foo@users.sourceforge.net>
 * @version $Revision: 2985 $
 */

#include <windows.h>
#include <jni.h>
#include "org_lwjgl_opengl_WindowsDisplay.h"
#include "display.h"
#include "common_tools.h"

static jobject createDisplayMode(JNIEnv *env, DEVMODE *devmode) {
	jclass displayModeClass;

	jmethodID displayModeConstructor;

	displayModeClass = (*env)->FindClass(env, "org/lwjgl/opengl/DisplayMode");
	if (displayModeClass == NULL)
		return NULL;
	displayModeConstructor = (*env)->GetMethodID(env, displayModeClass, "<init>", "(IIII)V");
	if (displayModeConstructor == NULL)
		return NULL;

	return (*env)->NewObject(env, displayModeClass, displayModeConstructor, 
			devmode->dmPelsWidth, devmode->dmPelsHeight,
			devmode->dmBitsPerPel, devmode->dmDisplayFrequency);
}

/**
 * Choose displaymodes using extended codepath (multiple displaydevices)
 */
jobjectArray getAvailableDisplayModes(JNIEnv * env) {

	int i = 0, j = 0, n = 0;

//	DISPLAY_DEVICE DisplayDevice;
	DEVMODE DevMode;
	jobject *display_mode_objects = NULL;
	int list_size = 0;

	jclass displayModeClass;
	jobjectArray ret;
	displayModeClass = (*env)->FindClass(env, "org/lwjgl/opengl/DisplayMode");

	ZeroMemory(&DevMode, sizeof(DEVMODE));
//	ZeroMemory(&DisplayDevice, sizeof(DISPLAY_DEVICE));

	DevMode.dmSize = sizeof(DEVMODE);
//	DisplayDevice.cb = sizeof(DISPLAY_DEVICE);

	/* Multi-monitor stuff commented out since we're only really interested in the primary monitor */
/*	while(EnumDisplayDevices(NULL, i++, &DisplayDevice, 0) != 0) {
		// continue if mirroring device
		if((DisplayDevice.StateFlags & DISPLAY_DEVICE_MIRRORING_DRIVER) != 0) {
			continue;
		}

		j = 0;
		while(EnumDisplaySettings((const char *) DisplayDevice.DeviceName, j++, &DevMode) != 0) {*/
		while(EnumDisplaySettings(NULL, j++, &DevMode) != 0) {
			// Filter out indexed modes
			if (DevMode.dmBitsPerPel > 8 && ChangeDisplaySettings(&DevMode, CDS_FULLSCREEN | CDS_TEST) == DISP_CHANGE_SUCCESSFUL) {
				jobject displayMode;
				if (list_size <= n) {
					list_size += 1;
					display_mode_objects = (jobject *)realloc(display_mode_objects, sizeof(jobject)*list_size);
					if (display_mode_objects == NULL)
						return NULL;
				}
				displayMode = createDisplayMode(env, &DevMode);
				display_mode_objects[n++] = displayMode;
			}
		}
//	}
	printfDebugJava(env, "Found %d displaymodes", n);

	ret = (*env)->NewObjectArray(env, n, displayModeClass, NULL);
	for (i = 0; i < n; i++) {
		(*env)->SetObjectArrayElement(env, ret, i, display_mode_objects[i]);
	}
	free(display_mode_objects);   
	return ret;
}

void switchDisplayMode(JNIEnv * env, jobject mode) {
	DEVMODE devmode;

	jclass cls_displayMode = (*env)->GetObjectClass(env, mode);
	jfieldID fid_width = (*env)->GetFieldID(env, cls_displayMode, "width", "I");
	jfieldID fid_height = (*env)->GetFieldID(env, cls_displayMode, "height", "I");
	jfieldID fid_bpp = (*env)->GetFieldID(env, cls_displayMode, "bpp", "I");
	jfieldID fid_freq = (*env)->GetFieldID(env, cls_displayMode, "freq", "I");

	int width = (*env)->GetIntField(env, mode, fid_width);
	int height = (*env)->GetIntField(env, mode, fid_height);
	int bpp = (*env)->GetIntField(env, mode, fid_bpp);
	int freq = (*env)->GetIntField(env, mode, fid_freq);
	LONG cdsret;

	ZeroMemory(&devmode, sizeof(DEVMODE));
	devmode.dmSize = sizeof(DEVMODE);
	devmode.dmBitsPerPel = bpp;
	devmode.dmPelsWidth = width;
	devmode.dmPelsHeight = height;
	devmode.dmDisplayFrequency = freq;
	devmode.dmFields = DM_BITSPERPEL | DM_PELSWIDTH | DM_PELSHEIGHT;
	if (freq != 0)
		devmode.dmFields |= DM_DISPLAYFREQUENCY;
	cdsret = ChangeDisplaySettings(&devmode, CDS_FULLSCREEN);

	if (cdsret != DISP_CHANGE_SUCCESSFUL) {
		/* What's the proper way to do this multiply with 2 thing, if at all necessary? */
/*		// Failed: so let's check to see if it's a wierd dual screen display
		printfDebugJava(env, "Failed to set display mode (%ld) ... assuming dual monitors", cdsret);
		devmode.dmPelsWidth = width * 2;
		cdsret = ChangeDisplaySettings(&devmode, CDS_FULLSCREEN);

		if (cdsret != DISP_CHANGE_SUCCESSFUL) {
			printfDebugJava(env, "Failed to set display mode using dual monitors (%ld)", cdsret);*/
			throwFormattedException(env, "Failed to set display mode (%ld).", cdsret);
			return;
//		}
	}
}

static jobject createNativeGammaBuffer(JNIEnv *env) {
	return newJavaManagedByteBuffer(env, sizeof(WORD)*3*org_lwjgl_opengl_WindowsDisplay_GAMMA_LENGTH);
}

jobject getCurrentGammaRamp(JNIEnv *env) {
	jobject gamma_buffer;
	WORD *gamma;
	HDC screenDC;

	gamma_buffer = createNativeGammaBuffer(env);
	if (gamma_buffer == NULL)
		return NULL;
	gamma = (WORD *)(*env)->GetDirectBufferAddress(env, gamma_buffer);

	// Get the screen
	screenDC = GetDC(NULL);
	if (screenDC == NULL) {
		throwException(env, "Couldn't get screen DC!");
		return NULL;
	}
	// Get the default gamma ramp
	if (GetDeviceGammaRamp(screenDC, gamma) == FALSE) {
		printfDebugJava(env, "Failed to get initial device gamma");
	}
	ReleaseDC(NULL, screenDC);
	return gamma_buffer;
}

void setGammaRamp(JNIEnv * env, jobject gammaRampBuffer) {
	HDC screenDC;
	WORD *gammaRamp = (WORD *)(*env)->GetDirectBufferAddress(env, gammaRampBuffer);

	screenDC = GetDC(NULL);
	if (SetDeviceGammaRamp(screenDC, gammaRamp) == FALSE) {
		throwException(env, "Failed to set device gamma.");
	}
	ReleaseDC(NULL, screenDC);
}

jobject convertToNativeRamp(JNIEnv *env, jobject float_gamma_obj) {
	int i;
	float scaledRampEntry;
	WORD rampEntry;
	const float *gammaRamp = (const float *)(*env)->GetDirectBufferAddress(env, float_gamma_obj);
	jint gamma_ramp_length = (*env)->GetDirectBufferCapacity(env, float_gamma_obj);
	jobject native_ramp;
	WORD *native_ramp_buffer;

	native_ramp = createNativeGammaBuffer(env);
	if (native_ramp == NULL)
		return NULL;
	native_ramp_buffer = (WORD *)(*env)->GetDirectBufferAddress(env, native_ramp);
	// Turn array of floats into array of RGB WORDs

	for (i = 0; i < gamma_ramp_length; i++) {
		scaledRampEntry = gammaRamp[i]*0xffff;
		rampEntry = (WORD)scaledRampEntry;
		native_ramp_buffer[i] = rampEntry;
		native_ramp_buffer[i + org_lwjgl_opengl_WindowsDisplay_GAMMA_LENGTH] = rampEntry;
		native_ramp_buffer[i + 2*org_lwjgl_opengl_WindowsDisplay_GAMMA_LENGTH] = rampEntry;
	}
	return native_ramp;
}

jobject getCurrentDisplayMode(JNIEnv * env) {
	DEVMODE devmode;
	if (!EnumDisplaySettings(NULL, ENUM_CURRENT_SETTINGS, &devmode)) {
		throwFormattedException(env, "Couldn't get current display settings (%ld)", GetLastError());
		return NULL;
	}
	return createDisplayMode(env, &devmode);
}

void resetDisplayMode(JNIEnv * env) {
	// Under Windows, all we have to do is:
	ChangeDisplaySettings(NULL, 0);
}

jobject getVersion(JNIEnv * env, char *driver)
{
	DWORD var = 0;
	DWORD dwInfoSize;
	LPVOID lpInfoBuff;
	BOOL bRetval;
	jclass version_class;
	jmethodID version_cons;
	jobject ret = NULL;

	version_class = (*env)->FindClass(env, "org/lwjgl/opengl/WindowsFileVersion");
	if (version_class == NULL)
		return NULL;
	version_cons = (*env)->GetMethodID(env, version_class, "<init>", "(II)V");
	if (version_cons == NULL)
		return NULL;

	dwInfoSize = GetFileVersionInfoSize(driver, &var);
	lpInfoBuff = malloc(dwInfoSize);
	if (lpInfoBuff == NULL) {
		throwException(env, "Failed to allocate lpInfoBuff");
		return NULL;
	}
	bRetval = GetFileVersionInfo(driver, 0, dwInfoSize, lpInfoBuff);
	if (bRetval != 0) {
		VS_FIXEDFILEINFO * fxdFileInfo;

		UINT uiLen = 0;
		bRetval = VerQueryValue(lpInfoBuff, TEXT("\\"), (void *)&fxdFileInfo, &uiLen);
		if (bRetval != 0)
			ret = (*env)->NewObject(env, version_class, version_cons, fxdFileInfo->dwProductVersionMS, fxdFileInfo->dwProductVersionLS);
	}

	free(lpInfoBuff);

	return ret;
}