/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.

 * This program 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 General Public License for more details.

 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * $URL$
 * $Id$
 *
 */

#include "common/util.h"
#include "common/stack.h"
#include "graphics/primitives.h"

#include "sci/sci.h"
#include "sci/engine/state.h"
#include "sci/tools.h"
#include "sci/gui/gui.h"
#include "sci/gui/gui_screen.h"
#include "sci/gui/gui_palette.h"
#include "sci/gui/gui_transitions.h"

namespace Sci {

SciGuiTransitions::SciGuiTransitions(SciGui *gui, SciGuiScreen *screen, SciGuiPalette *palette, bool isVGA)
	: _gui(gui), _screen(screen), _palette(palette), _isVGA(isVGA) {
	init();
}

SciGuiTransitions::~SciGuiTransitions() {
	delete[] _oldScreen;
}

// This table contains a mapping between oldIDs (prior SCI1LATE) and newIDs
static const GuiTransitionTranslateEntry oldTransitionIDs[] = {
	{   0, SCI_TRANSITIONS_VERTICALROLLFROMCENTER,		false },
	{   1, SCI_TRANSITIONS_HORIZONTALROLLFROMCENTER,	false },
	{   8, SCI_TRANSITIONS_BLOCKS,						false },
	{   9, SCI_TRANSITIONS_VERTICALROLLTOCENTER,		false },
	{  10, SCI_TRANSITIONS_HORIZONTALROLLTOCENTER,		false },
	{  17, SCI_TRANSITIONS_BLOCKS,						true },
	{  18, SCI_TRANSITIONS_PIXELATION,					false },
	{  27, SCI_TRANSITIONS_PIXELATION	,				true },
	{  30, SCI_TRANSITIONS_FADEPALETTE,					false },
	{  40, SCI_TRANSITIONS_SCROLLRIGHT,					false },
	{  41, SCI_TRANSITIONS_SCROLLLEFT,					false },
	{  42, SCI_TRANSITIONS_SCROLLUP,					false },
	{  43, SCI_TRANSITIONS_SCROLLDOWN,					false },
	{ 100, SCI_TRANSITIONS_NONE,						false },
	{ 255, 255,											false }
};

void SciGuiTransitions::init() {
	_oldScreen = new byte[_screen->_displayHeight * _screen->_displayWidth];

	if (getSciVersion() >= SCI_VERSION_1_LATE)
		_translationTable = NULL;
	else
		_translationTable = oldTransitionIDs;
}

void SciGuiTransitions::setup(int16 number, bool blackoutFlag) {
	_number = number;
	_blackoutFlag = blackoutFlag;
}

void SciGuiTransitions::doit(Common::Rect picRect) {
	const GuiTransitionTranslateEntry *translationEntry = _translationTable;

	_picRect = picRect;

	if (translationEntry) {
		// We need to translate the ID
		while (1) {
			if (translationEntry->oldId == 255) {
				warning("SciGuiTransitions: old ID %d not supported", _number);
				setNewPalette(); setNewScreen();
				_screen->_picNotValid = 0;
				return;
			}
			if (translationEntry->oldId == _number) {
				_number = translationEntry->realId;
				_blackoutFlag = translationEntry->blackoutFlag;
				break;
			}
			translationEntry++;
		}
	}

	if (_blackoutFlag)
		warning("SciGuiTransitions: blackout flag currently not supported");

	switch (_number) {
	case SCI_TRANSITIONS_VERTICALROLLFROMCENTER:
		setNewPalette(); verticalRollFromCenter();
		break;
	case SCI_TRANSITIONS_VERTICALROLLTOCENTER:
		setNewPalette(); verticalRollFromCenter();
		break;
	case SCI_TRANSITIONS_HORIZONTALROLLFROMCENTER:
		setNewPalette(); horizontalRollFromCenter();
		break;
	case SCI_TRANSITIONS_HORIZONTALROLLTOCENTER:
		setNewPalette(); horizontalRollToCenter();
		break;

	case SCI_TRANSITIONS_PIXELATION:
		setNewPalette(); pixelation();
		break;

	case SCI_TRANSITIONS_BLOCKS:
		setNewPalette(); blocks();
		break;

	case SCI_TRANSITIONS_FADEPALETTE:
		fadeOut(); setNewScreen(); fadeIn();
		break;

	case SCI_TRANSITIONS_SCROLLRIGHT:
	case SCI_TRANSITIONS_SCROLLLEFT:
	case SCI_TRANSITIONS_SCROLLUP:
	case SCI_TRANSITIONS_SCROLLDOWN:
		setNewPalette(); scroll();
		break;

	case SCI_TRANSITIONS_NONE_LONGBOW:
	case SCI_TRANSITIONS_NONE:
		setNewPalette(); setNewScreen();
		break;
	default:
		warning("SciGuiTransitions: ID %d not implemented", _number);
		setNewPalette(); setNewScreen();
	}

	_screen->_picNotValid = 0;
}

void SciGuiTransitions::setNewPalette() {
	if (_isVGA)
		_palette->setOnScreen();
}

void SciGuiTransitions::setNewScreen() {
	_screen->copyRectToScreen(_picRect);
	g_system->updateScreen();
}

// Note: dont do too many steps in here, otherwise cpu will crap out because of the load
void SciGuiTransitions::fadeOut() {
	byte oldPalette[4 * 256], workPalette[4 * 256];
	int16 stepNr, colorNr;

	g_system->grabPalette(oldPalette, 0, 256);

	for (stepNr = 100; stepNr >= 0; stepNr -= 10) {
		for (colorNr = 1; colorNr < 255; colorNr++){
			workPalette[colorNr * 4 + 0] = oldPalette[colorNr * 4] * stepNr / 100;
			workPalette[colorNr * 4 + 1] = oldPalette[colorNr * 4 + 1] * stepNr / 100;
			workPalette[colorNr * 4 + 2] = oldPalette[colorNr * 4 + 2] * stepNr / 100;
		}
		g_system->setPalette(workPalette + 4, 1, 254);
		_gui->wait(2);
	}
}

// Note: dont do too many steps in here, otherwise cpu will crap out because of the load
void SciGuiTransitions::fadeIn() {
	int16 stepNr;

	for (stepNr = 0; stepNr <= 100; stepNr += 10) {
		_palette->setIntensity(1, 254, 100, true);
		_gui->wait(2);
	}
}

// pixelates the new picture over the old one - works against the whole screen
void SciGuiTransitions::pixelation () {
	uint16 mask = 0x40, stepNr = 0;
	Common::Rect pixelRect;

	do {
		mask = (mask & 1) ? (mask >> 1) ^ 0xB400 : mask >> 1;
		if (mask >= 320 * 200)
			continue;
		pixelRect.left = mask % 320; pixelRect.right = pixelRect.left + 1;
		pixelRect.top = mask / 320;	pixelRect.bottom = pixelRect.top + 1;
		_screen->copyRectToScreen(pixelRect);
		if ((stepNr & 0x3FF) == 0) {
			g_system->updateScreen();
			g_system->delayMillis(5);
		}
		stepNr++;
	} while (mask != 0x40);
}

// like pixelation but uses 8x8 blocks - works against the whole screen
void SciGuiTransitions::blocks() {
	uint16 mask = 0x40, stepNr = 0;
	Common::Rect blockRect;

	do {
		mask = (mask & 1) ? (mask >> 1) ^ 0x240 : mask >> 1;
		if (mask >= 40 * 25)
			continue;
		blockRect.left = (mask % 40) << 3; blockRect.right = blockRect.left + 8;
		blockRect.top = (mask / 40) << 3; blockRect.bottom = blockRect.top + 8;
		_screen->copyRectToScreen(blockRect);
		if ((stepNr & 7) == 0) {
			g_system->updateScreen();
			g_system->delayMillis(4);
		}
		stepNr++;
	} while (mask != 0x40);
}

// scroll old screen (up/down/left/right) and insert new screen that way - works on _picRect area only
void SciGuiTransitions::scroll() {
	int16 screenWidth, screenHeight;
	byte *oldScreenPtr;
	int16 stepNr = 0;
	Common::Rect oldMoveRect = _picRect;
	Common::Rect newMoveRect = _picRect;
	Common::Rect newScreenRect = _picRect;

	_screen->copyFromScreen(_oldScreen);
	screenWidth = _screen->_displayWidth; screenHeight = _screen->_displayHeight;

	oldScreenPtr = _oldScreen + _picRect.left + _picRect.top * screenWidth;

	switch (_number) {
	case SCI_TRANSITIONS_SCROLLLEFT:
		newScreenRect.right = newScreenRect.left;
		newMoveRect.left = newMoveRect.right;
		while (oldMoveRect.left < oldMoveRect.right) {
			oldScreenPtr++; oldMoveRect.right--;
			if (oldMoveRect.right > oldMoveRect.left)
				g_system->copyRectToScreen(oldScreenPtr, screenWidth, oldMoveRect.left, oldMoveRect.top, oldMoveRect.width(), oldMoveRect.height());
			newScreenRect.right++; newMoveRect.left--;
			_screen->copyRectToScreen(newScreenRect, newMoveRect.left, newMoveRect.top);
			if ((stepNr & 1) == 0) {
				g_system->updateScreen();
				g_system->delayMillis(1);
			}
			stepNr++;
		}
		if ((stepNr & 1) == 0)
			g_system->updateScreen();
		break;

	case SCI_TRANSITIONS_SCROLLRIGHT:
		newScreenRect.left = newScreenRect.right;
		while (oldMoveRect.left < oldMoveRect.right) {
			oldMoveRect.left++;
			if (oldMoveRect.right > oldMoveRect.left)
				g_system->copyRectToScreen(oldScreenPtr, screenWidth, oldMoveRect.left, oldMoveRect.top, oldMoveRect.width(), oldMoveRect.height());
			newScreenRect.left--;
			_screen->copyRectToScreen(newScreenRect, newMoveRect.left, newMoveRect.top);
			if ((stepNr & 1) == 0) {
				g_system->updateScreen();
				g_system->delayMillis(1);
			}
			stepNr++;
		}
		if ((stepNr & 1) == 0)
			g_system->updateScreen();
		break;

	case SCI_TRANSITIONS_SCROLLUP:
		newScreenRect.bottom = newScreenRect.top;
		newMoveRect.top = newMoveRect.bottom;
		while (oldMoveRect.top < oldMoveRect.bottom) {
			oldScreenPtr += screenWidth; oldMoveRect.top++;
			if (oldMoveRect.top < oldMoveRect.bottom)
				g_system->copyRectToScreen(oldScreenPtr, screenWidth, _picRect.left, _picRect.top, oldMoveRect.width(), oldMoveRect.height());
			newScreenRect.bottom++;	newMoveRect.top--;
			_screen->copyRectToScreen(newScreenRect, newMoveRect.left, newMoveRect.top);
			g_system->updateScreen();
			g_system->delayMillis(3);
		}
		break;

	case SCI_TRANSITIONS_SCROLLDOWN:
		newScreenRect.top = newScreenRect.bottom;
		while (oldMoveRect.top < oldMoveRect.bottom) {
			oldMoveRect.top++;
			if (oldMoveRect.top < oldMoveRect.bottom)
				g_system->copyRectToScreen(oldScreenPtr, screenWidth, oldMoveRect.left, oldMoveRect.top, oldMoveRect.width(), oldMoveRect.height());
			newScreenRect.top--;
			_screen->copyRectToScreen(newScreenRect, _picRect.left, _picRect.top);
			g_system->updateScreen();
			g_system->delayMillis(3);
		}
		break;
	}
}

// vertically displays new screen starting from center - works on _picRect area only
void SciGuiTransitions::verticalRollFromCenter() {
	Common::Rect leftRect = Common::Rect(_picRect.left + (_picRect.width() / 2) -1, _picRect.top, _picRect.left + (_picRect.width() / 2), _picRect.bottom);
	Common::Rect rightRect = Common::Rect(leftRect.right, _picRect.top, leftRect.right + 1, _picRect.bottom);

	while ((leftRect.left > _picRect.left) && (rightRect.right < _picRect.right)) {
		if (leftRect.left < _picRect.left)
			leftRect.translate(1, 0);
		if (rightRect.right > _picRect.right)
			rightRect.translate(-1, 0);
		_screen->copyRectToScreen(leftRect); leftRect.translate(-1, 0);
		_screen->copyRectToScreen(rightRect); rightRect.translate(1, 0);
		g_system->updateScreen();
		g_system->delayMillis(2);
	}
}

// vertically displays new screen starting from edges - works on _picRect area only
void SciGuiTransitions::verticalRollToCenter() {
	Common::Rect leftRect = Common::Rect(_picRect.left, _picRect.top, _picRect.left + 1, _picRect.bottom);
	Common::Rect rightRect = Common::Rect(leftRect.right - 1, _picRect.top, leftRect.right, _picRect.bottom);

	while (leftRect.left < rightRect.right) {
		_screen->copyRectToScreen(leftRect); leftRect.translate(1, 0);
		_screen->copyRectToScreen(rightRect); rightRect.translate(-1, 0);
		g_system->updateScreen();
		g_system->delayMillis(2);
	}
}

// horizontally displays new screen starting from center - works on _picRect area only
void SciGuiTransitions::horizontalRollFromCenter() {
	Common::Rect upperRect = Common::Rect(_picRect.left, _picRect.top + (_picRect.height() / 2) - 1, _picRect.right, _picRect.top + (_picRect.height() / 2));
	Common::Rect lowerRect = Common::Rect(upperRect.left, upperRect.bottom, upperRect.right, upperRect.bottom + 1);

	while ((upperRect.top > _picRect.top) && (lowerRect.bottom < _picRect.bottom)) {
		if (upperRect.top < _picRect.top)
			upperRect.translate(0, 1);
		if (lowerRect.bottom > _picRect.bottom)
			lowerRect.translate(0, -1);
		_screen->copyRectToScreen(upperRect); upperRect.translate(0, -1);
		_screen->copyRectToScreen(lowerRect); lowerRect.translate(0, 1);
		g_system->updateScreen();
		g_system->delayMillis(3);
	}
}

// horizontally displays new screen starting from upper and lower edge - works on _picRect area only
void SciGuiTransitions::horizontalRollToCenter() {
	Common::Rect upperRect = Common::Rect(_picRect.left, _picRect.top, _picRect.right, _picRect.top + 1);
	Common::Rect lowerRect = Common::Rect(upperRect.left, _picRect.bottom - 1, upperRect.right, _picRect.bottom);

	while (upperRect.top < lowerRect.bottom) {
		_screen->copyRectToScreen(upperRect); upperRect.translate(0, 1);
		_screen->copyRectToScreen(lowerRect); lowerRect.translate(0, -1);
		g_system->updateScreen();
		g_system->delayMillis(3);
	}
}

} // End of namespace Sci