/* 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.
 *
 */

/*
 * This code is based on original Soltys source code
 * Copyright (c) 1994-1995 Janus B. Wisniewski and L.K. Avalon
 */

#ifndef __CGE_WALK__
#define __CGE_WALK__

#include "cge/wav.h"
#include "cge/vga13h.h"
#include "cge/events.h"

namespace CGE {

#define kMapXCnt       40
#define kMapZCnt       20
#define kMapTop        80
#define kMapHig        80
#define kMapGridX      (kScrWidth / kMapXCnt)
#define kMapGridZ      (kMapHig / kMapZCnt)
#define kMaxFindLevel  3

enum Dir { kDirNone = -1, kDirNorth, kDirEast, kDirSouth, kDirWest };

class Couple {
protected:
	signed char _a;
	signed char _b;
public:
	Couple(const signed char a, const signed char b) : _a(a), _b(b) { }
	Couple operator + (Couple c) {
		return Couple(_a + c._a, _b + c._b);
	}

	void operator += (Couple c) {
		_a += c._a;
		_b += c._b;
	}

	Couple operator - (Couple c) {
		return Couple(_a - c._a, _b - c._b);
	}

	void operator -= (Couple c) {
		_a -= c._a;
		_b -= c._b;
	}

	bool operator == (const Couple &c) {
		return ((_a - c._a) | (_b - c._b)) == 0;
	}

	bool operator != (Couple c) {
		return !(operator == (c));
	}

	void split(signed char &a, signed char &b) {
		a = _a;
		b = _b;
	}
};

class Cluster : public Couple {
public:
	static uint8 _map[kMapZCnt][kMapXCnt];
	static CGEEngine *_vm;

	static void init(CGEEngine *vm);
public:
	uint8 &cell();
	Cluster(int a, int b) : Couple(a, b) { }
	Cluster() : Couple (-1, -1) { }
	bool chkBar() const;
	bool isValid() const;

};


class Walk : public Sprite {
private:
	CGEEngine *_vm;
public:
	Cluster _here;
	int _tracePtr;
	int _level;
	int _findLevel;
	Couple _target;
	Cluster _trace[kMaxFindLevel];

	Dir _dir;
	Walk(CGEEngine *vm, BitmapPtr *shpl);
	void tick();
	void findWay(Cluster c);
	void findWay(Sprite *spr);
	int distance(Sprite *spr);
	void turn(Dir d);
	void park();
	bool lower(Sprite *spr);
	void reach(Sprite *spr, int mode = -1);

	void noWay();
	bool find1Way(Cluster c);
};

Cluster XZ(int x, int y);
Cluster XZ(Couple xy);

extern Walk *_hero;

} // End of namespace CGE

#endif