// locates a WingedShooter with less than 'full' (0.9)
// energy and resupplies it with a cell that's at least at
// 'minevel' (0.8).
// precond: hands empty or carrying power cell
extern void object::ReloadWingedShooter()
{
	// level at which we decide to reload power cells
	float minLevel = 0.8;
	
	// full is defined in pickNonFullWS, below
	
	point home = position;
	
	object ws = pickNonFullWS();
	if (ws == null) {
		message("Nobody to resupply");
		return;
	}
	if (load==null) grabPowerCell();
	if (load.category!=PowerCell) {
		message("I cannot resupply the WS because I am carrrying something already");
		// (and it's not a power cell)
		return;
	}
	
	if (load.energyLevel<minLevel) {
		message("reloading power cell first, it is below "+minLevel);
		sub_reload();
	}
	
	/// go to winged shooter and replace power cell
	
	goto(ws.position);
	if (ws.load!=null) {
		// switch old cell for new
		message("Removing old cell");
		drop(Behind); // drop our loaded cell
		grab(); // take old one
		turn(90);
		drop(); // drop old one
		turn(-90);
		grab(Behind); // take loaded cell
	}
	// insert new cell in winged shooter
	drop();
	
	
	message("Done refueling WS, returning to starting point");
	goto(home);
}

// makes sure we grab a power cell. Gets a power cell around
// us or from the power plant if that's closer.
// precond: hands empty
void object::grabPowerCell() {
	
	object energy = radar(PowerCell);
	object factory = radar(PowerPlant);
	
	if (factory!=null) {
		object bat = factory.energyCell;
		if (null!=bat) {
			// power plant has a battery ready
			if (distance(position,bat.position)<distance(position,energy.position)) {
				// power plant is closer, take its battery
				// instead
				energy = bat;
			}
		}
	}
	
	if (energy == null) {
		message("No power cell around");
		return;
	}
	
	goto(energy.position);
	grab();
}

// reload power and shield
void object::sub_reload()
{
	object item;           // info. about power station
	
	point start = position;      // store initial position
	
	item = radar(PowerStation); // look for station
	goto(item.position);   // go to the power station
	
	object l = load;
	if (null!=l) {
		if (l.category != EnergyCell) l = null;
	}
	int cl = 0;
	if (l == null) cl = 1;
	else cl = l.energyLevel;
	
	while ( energyCell.energyLevel < 1 or cl < 1)
	{
		wait(1);            // wait until recharged
		if (l == null) cl = 1;
		else cl = l.energyLevel;
	}
	
	object rep = radar(RepairCenter);
	if (shieldLevel<1.0 and null!=rep) {
		goto(rep.position);
		while (shieldLevel<1.0) {
			wait(1);
		}
	}
	message("Recharge completed");
}

// returns a winged shooter with energy below 'full',
// or null if none exist
object object::pickNonFullWS() {
	
	// we will not pick a WS with power above this level
	float full=1;
	
	float m =0;
	int count=0;
	object ws = null;
	float l; // energy level of WS in consideration
	do {
		count++;
		ws = radar(WingedShooter,0,360,m);
		l=0;
		if (null!=ws){
			if (null!=ws.energyCell) {
				l = ws.energyCell.energyLevel;
			}
		}
		
		if (l>=full and null!=ws) {
			m=distance(position,ws.position)+0.1;
			ws = null;
		} else if (null!=ws) {
			message("picked a WS with energy ("+l+")");
		}
	} while (l>=full and count<100);
	if (null==ws) {
		message("There is no WS under "+full+" around");
	}
	return ws;
}