// Copyright (c) Hercules Dev Team, licensed under GNU GPL.
// See the LICENSE file
// Portions Copyright (c) Athena Dev Teams

#ifndef _PATH_H_
#define _PATH_H_

#include "map.h" // enum cell_chk

#define MOVE_COST 10
#define MOVE_DIAGONAL_COST 14

#define MAX_WALKPATH 32

struct walkpath_data {
	unsigned char path_len,path_pos;
	unsigned char path[MAX_WALKPATH];
};

struct shootpath_data {
	int rx,ry,len;
	int x[MAX_WALKPATH];
	int y[MAX_WALKPATH];
};

#define check_distance_bl(bl1, bl2, distance) path->check_distance((bl1)->x - (bl2)->x, (bl1)->y - (bl2)->y, distance)
#define check_distance_blxy(bl, x1, y1, distance) path->check_distance((bl)->x-(x1), (bl)->y-(y1), distance)
#define check_distance_xy(x0, y0, x1, y1, distance) path->check_distance((x0)-(x1), (y0)-(y1), distance)

#define distance_bl(bl1, bl2) path->distance((bl1)->x - (bl2)->x, (bl1)->y - (bl2)->y)
#define distance_blxy(bl, x1, y1) path->distance((bl)->x-(x1), (bl)->y-(y1))
#define distance_xy(x0, y0, x1, y1) path->distance((x0)-(x1), (y0)-(y1))

struct path_interface {
	// calculates destination cell for knockback
	int (*blownpos) (int16 m, int16 x0, int16 y0, int16 dx, int16 dy, int count);
	// tries to find a walkable path
	bool (*search) (struct walkpath_data *wpd, int16 m, int16 x0, int16 y0, int16 x1, int16 y1, int flag, cell_chk cell);
	// tries to find a shootable path
	bool (*search_long) (struct shootpath_data *spd, int16 m, int16 x0, int16 y0, int16 x1, int16 y1, cell_chk cell);
	int (*check_distance) (int dx, int dy, int distance);
	unsigned int (*distance) (int dx, int dy);
};

struct path_interface *path;

void path_defaults(void);

#endif /* _PATH_H_ */