public void SetGemsInSlot(IReadOnlyList <Gem> value, ItemSlot slot)
{
if (value.Any(s => s.ItemSlot != slot))
{
throw new ArgumentException("Gems for a slot must all have that slot as ItemSlot", nameof(value));
}
var oldValue = GetGemsInSlot(slot);
if (oldValue.Any() && value.Any())
{
Gems.RemoveAndAdd(oldValue, value);
}
else if (value.Any())
{
Gems.Add(value);
}
else if (oldValue.Any())
{
Gems.Remove(oldValue);
}
}