/* smartTrigger.cc
   triggers a scheme expression when player is within radius

   Copyright (C) 2000  Mathias Broxvall

   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
*/

#include "general.h"
#include "smartTrigger.h"
#include "game.h"
#include "player.h"
#include "libguile.h"

using namespace std;

SmartTrigger::SmartTrigger(Real x,Real y,Real radius,SCM entering,SCM leaving)
  :GameHook(), x(x), y(y), radius(radius), entering(entering), leaving(leaving), wasIn(0) {
  if(entering)
	scm_gc_protect_object(entering);
  if(leaving)
	scm_gc_protect_object(leaving);
}
SmartTrigger::~SmartTrigger() {
  if(entering)
	scm_gc_unprotect_object(entering);
  if(leaving)
	scm_gc_unprotect_object(leaving);
  this->GameHook::~GameHook();
}
void SmartTrigger::tick(Real t) {
  Player *ply = Game::current->player1;
  double dx = ply->position[0] - x;
  double dy = ply->position[1] - y;
  if(dx*dx+dy*dy < radius*radius) {
	if(!wasIn && entering) scm_apply_0(entering,SCM_EOL);
	wasIn=1;
  } else {
	if(wasIn && leaving) scm_apply_0(leaving,SCM_EOL);
	wasIn=0;
  }
}