#include <stdio.h>
#include <assert.h>

#include "position.h"
#include "pie/dib24.h"

void print_dirs(direction_t dirs)
{
  printf("[ ");

  if ( dirs == DIR_NONE )
    printf("NONE ");

  if ( dirs & DIR_UP )
    printf("UP ");
  if ( dirs & DIR_DOWN )
    printf("DOWN ");
  if ( dirs & DIR_LEFT )
    printf("LEFT ");
  if ( dirs & DIR_RIGHT )
    printf("RIGHT ");
  printf("]\n");
}

direction_t dir_invert(direction_t dir)
{
  switch( dir )
    {
    case DIR_UP:
      return DIR_DOWN;

    case DIR_DOWN:
      return DIR_UP;

    case DIR_LEFT:
      return DIR_RIGHT;

    case DIR_RIGHT:
      return DIR_LEFT;

    default:
      assert(!"should never happen");
    }
}

/**
 * We assume there are only horizontal tunnels
 */
unsigned int move_safe(Dib24 *xi,
		       unsigned int xy,
		       direction_t dir,
		       unsigned int distance)
{
  int next_xy;

  switch ( dir )
    {
    case DIR_LEFT:
      next_xy = xy - distance;
      /* Handle tunnel */
      if ( next_xy < 0 )
	next_xy = xi->getWidth() - (1 + next_xy + 1);
      break;

    case DIR_RIGHT:
      next_xy = xy + distance;
      /* Handle tunnel */
      if ( next_xy >= xi->getWidth() )
	next_xy = 0 + (next_xy - xi->getWidth());
      break;

    case DIR_UP:
      next_xy = xy - distance;
      break;

    case DIR_DOWN:
      next_xy = xy + distance;
      break;

    default:
      assert(!"Should never land here!");
    }

  return next_xy;
}