/*
 * bullets.c
 *
 * Handle bullets (shots and clusterbombs) in flight
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <math.h>
#include "graphics.h"
#include "grv.h"

struct bullet {
  int x, y;			/* Current location */
  int dx, dy;			/* Direction of movement */
  int color;			/* Color */
};

#define MAX_BULLETS 57		/* 8 clusterbombs*7 shards + 1 player shot */
/* Two lists; flip between loops */
static struct bullet bullet_lists[2][MAX_BULLETS];
static struct bullet *bullets = bullet_lists[0];
static int bullet_list = 0;
static int nbullets = 0;

/*
 * Add a bullet to the list
 */
void add_bullet(int x, int y, int dx, int dy, int color)
{
  int n;

  if ( nbullets >= MAX_BULLETS )
    return;

  n = nbullets++;

  bullets[n].x     = x;
  bullets[n].y     = y;
  bullets[n].dx    = dx;
  bullets[n].dy    = dy;
  bullets[n].color = color;
}

/*
 * Run bullet action
 */
void run_bullets(void)
{
  struct bullet *b, *bb, *eb;
  int x, y, s, f;
  int live;
  int hpp;

  while ( nbullets ) {
    bb = bullets;
    eb = &bullets[nbullets];

    /* Flip lists and initialize to zero */
    bullet_list ^= 1;
    bullets = bullet_lists[bullet_list];
    nbullets = 0;

    for ( b = bb ; b < eb ; b++ ) {
      live = 1;

      x = (b->x += b->dx);
      y = (b->y += b->dy);

      if ( x < 2 || x > 23 || y < 1 || y > 40 ) {
	live = 0;
	b->color = 0;		/* Don't draw */
      } else {
	s = screen(x, y);
	f = bg(x, y);

	if ( strchr("\xfe\xb0\xb1\xe5\xec\x04?" DOORS, s) ) {
	  live = 0;
	  b->color = 0;
	} else {
	  color(b->color, f);
	  lprint(x,y,"\xf9");

	  switch ( s ) {
	  case SYM_CHERRY:
	    take_cherry();
	    live = 0;
	    break;
	  case SYM_DIAMOND:
	    take_diamond();
	    live = 0;
	    break;
	  case SYM_GHOST:
	    kill_ghost(x,y);
	    live = 0;
	    break;
	  case 'H':
	    hpp = 0; goto hyper;
	  case 'Y':
	    hpp = 1; goto hyper;
	  case 'P':
	    hpp = 2; goto hyper;
	  case 'E':
	    hpp = 3; goto hyper;
	  case 'R':
	    hpp = 4; goto hyper;
	  hyper:
	    gp.Hyp++;
	    color(15,gp.c);
	    lprintf(25, 31+hpp*2, "%c", s);
	    live = 0;
	    break;
	  case SYM_CLUSTER:
	    {
	      int di, dj;
	      for ( di = -1 ; di <= 1 ; di++ )
		for ( dj = -1 ; dj <= 1 ; dj++ )
		  if ( (di||dj) && (di!=-b->dx || dj!=-b->dy) )
		    add_bullet(x,y,di,dj,12);
	      live = 0;
	    }
	    break;
	  default:
	    break;
	  }
	}
      }

      if ( live )
	add_bullet(x,y,b->dx,b->dy,b->color);
    }
    update_score();

    mymssleep(10);		/* Allow the user to notice :) */

    /* Erase bullets */
    for ( b = bb ; b < eb ; b++ ) {
      if ( b->color ) {
	color(0,bg(b->x,b->y));
	lprint(b->x,b->y," ");
      }
    }
  }
}