/* ScummVM - Scumm Interpreter
 * Copyright (C) 2003-2005 The ScummVM project
 *
 * 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 * $Header$
 *
 */

#ifndef SKYSCREEN_H
#define SKYSCREEN_H

#include "stdafx.h"
#include "common/scummsys.h"
#include "sky/skydefs.h"

class OSystem;

namespace Sky {

class Disk;
class SkyEngine;
class SkyCompact;
struct Compact;
struct dataFileHeader;

#define SCROLL_JUMP		16
#define VGA_COLOURS		256
#define GAME_COLOURS		240
#define SEQ_DELAY 3

#define FORE 1
#define BACK 0

typedef struct {
	uint16 yCood;
	Compact *compact;
	dataFileHeader *sprite;
} StSortList;

class Screen {
public:
	Screen(OSystem *pSystem, Disk *pDisk, SkyCompact *skyCompact);
	~Screen(void);
	void setPalette(uint8 *pal);
	void setPaletteEndian(uint8 *pal);
	void setPalette(uint16 fileNum);
	void paletteFadeUp(uint8 *pal);
	void paletteFadeUp(uint16 fileNr);

	void showScreen(uint16 fileNum);
	void showScreen(uint8 *pScreen);
	
	void handleTimer(void);
	void startSequence(uint16 fileNum);
	void startSequenceItem(uint16 itemNum);
	void stopSequence(void);
	bool sequenceRunning(void) { return _seqInfo.running; };
	void waitForSequence(void);
	uint32 seqFramesLeft(void) { return _seqInfo.framesLeft; };
	uint8 *giveCurrent(void) { return _currentScreen; };
	void halvePalette(void);

	//- regular screen.asm routines
	void forceRefresh(void) { memset(_gameGrid, 0x80, GRID_X * GRID_Y); };
	void fnFadeUp(uint32 palNum, uint32 scroll);
	void fnFadeDown(uint32 scroll);
	void fnDrawScreen(uint32 palette, uint32 scroll);
	void clearScreen(void);

	void recreate(void);
	void flip(bool doUpdate = true);

	void spriteEngine(void);

	void paintBox(uint16 x, uint16 y);
	void showGrid(uint8 *gridBuf);

private:
	OSystem *_system;
	Disk *_skyDisk;
	SkyCompact *_skyCompact;
	static uint8 _top16Colours[16*3];
	uint8 _palette[1024];
	uint32 _currentPalette;
	uint8 _seqGrid[20 * 12];

	bool volatile _gotTick;
	void waitForTimer(void);
	void processSequence(void);

	uint8 *_gameGrid;
	uint8 *_currentScreen;
	uint8 *_scrollScreen;
	struct {
		uint32 framesLeft;
		uint32 delay;
		uint8 *seqData;
		uint8 *seqDataPos;
		volatile bool running;
		bool runningItem; // when playing an item, don't free it afterwards.
	} _seqInfo;

	//- more regular screen.asm + layer.asm routines
	void convertPalette(uint8 *inPal, uint8* outPal);
	void palette_fadedown_helper(uint32 *pal, uint num);
	
	//- sprite.asm routines
	// fixme: get rid of these globals
	uint32 _sprWidth, _sprHeight, _sprX, _sprY, _maskX1, _maskX2;
	void doSprites(uint8 layer);
	void sortSprites(void);
	void drawSprite(uint8 *spriteData, Compact *sprCompact);
	void verticalMask(void);
	void vertMaskSub(uint16 *grid, uint32 gridOfs, uint8 *screenPtr, uint32 layerId);
	void vectorToGame(uint8 gridVal);
};

} // End of namespace Sky

#endif //SKYSCREEN_H