Feature - Implemented Revisit "Four Songs" and "Additional Song" boolean modifiers

// Return total number of active AT buffs
int active_songs(){
	int total = 0;
	foreach buff in my_effects(){
		if( buff.to_skill().class == $class[accordion thief] && buff.to_skill().buff ){ total += 1; }
	}
	return total;
}

// Number of AT songs you currently have active
int active_songs(){
	int total = 0;
	foreach activeEffect in my_effects(){
		if( activeEffect.to_skill().class == $class[accordion thief] && activeEffect.to_skill().buff ){ total += 1; }
	}
	return total;
}

// Return the number of songs you can currently hold in your head
int available_songs(){
	int total = 3;

	// Check for the non-stacking "Four Songs" effect
	if(boolean_modifier("Four Songs")){ total += 1; }

	// Check for skills that grant stacking Additional Songs, like Mariachi Memory
	foreach s in $skills[] {
		if(have_skill(s) && boolean_modifier(s, "additional song")){
				total += 1;
		}
	}

	// Check if any effects give Additional Songs
	foreach e in my_effects(){
		if(boolean_modifier(e, "additional song")){
			total += 1;
		}
	}

	// Check equipment for stacking Additional Songs effect
	// and ensure effect is available to your class
	foreach s in $slots[]{
		if(boolean_modifier(equipped_item(s), "additional song")
				&& class_modifier(equipped_item(s), "class") == my_class()){
					total += 1;
		}
	}
	return total;
}

> ash class_modifier($item[zombie accordion], "Class")

Returned: Accordion Thief
primestat => Moxie

// Return true if a slot is already giving a +songs bonus, false otherwise
boolean has_songs_bonus(slot itemSlot){
	if(boolean_modifier(equipped_item(itemSlot), "four songs")
			|| boolean_modifier(equipped_item(itemSlot), "additional song")){
				return true;
			}
	return false;
}

// Try to equip an item for a +songs bonus
boolean _equip_songs_bonus(item it){
	if(available_amount(it) > 0
			&& (equipped_amount(it) < 1 || !boolean_modifier(it, "single equip"))
			&& (class_modifier(it, "class") == $class[none] || class_modifier(it, "class") == my_class())){
				// make sure we don't un-equip an item giving us +songs currently
				if(has_songs_bonus(to_slot(it))){
					if(to_slot(it) == $slot[acc1]){
						// Special handling for accessory slot
						foreach s in $slots[acc1, acc2, acc3]{
							if(!has_songs_bonus(s)){
								return equip(s, it);
							}
						}
					}
				}
				else {
					return equip(it);
				}
	}
	return false;
}

// Change gear to attempt to increase your Accordion song limit by 1
boolean increase_songs_limit(){
	// Start with the "4 instead of 3" items, as you can only benefit from one
	if(!boolean_modifier("four songs")){
		foreach it in $items[] {
			if(boolean_modifier(it, "four songs") && _equip_songs_bonus(it)){
				return true;
			}
		}
	}

	// Look for Additional Song modifier items
	foreach it in $items[] {
		if(boolean_modifier(it, "additional song") && _equip_songs_bonus(it)){
			return true;
		}
	}
	return false;
}