public class AttributeBonus implements PassiveBonus {

    private final Attribute attribute;
    private final GemBonusType type;

    public AttributeBonus(Attribute attribute, GemBonusType type) {
        this.attribute = attribute;
        this.type = type;
    }

    @Override
    public void apply(Player player, float value) {
        System.out.println("Applying " + attribute.name() + " passive attribute value " + value + " to player " + player.getName());

        if(type == GemBonusType.PERCENTAGE)
            value /= 100;

        player.registerAttribute(this.attribute);
        AttributeInstance attribute = player.getAttribute(this.attribute);

        AttributeModifier modifier = getModifier(attribute);

        if (modifier != null)
            attribute.removeModifier(modifier);

        attribute.addModifier(new AttributeModifier("Gem-" + attribute, value, type.asModifierOperation()));
    }

    @Override
    public void stop(Player player, float value) {
        AttributeInstance attribute = player.getAttribute(this.attribute);

        AttributeModifier modifier = getModifier(attribute);

        if (modifier == null)
            return;

        attribute.removeModifier(modifier);
    }

    private AttributeModifier getModifier(AttributeInstance instance) {
        for (AttributeModifier modifier : instance.getModifiers())
            if (modifier.getName().equalsIgnoreCase("Gem-" + attribute))
                return modifier;

        return null;
    }
}