namespace DevDisciples.Parsing;

public class VisitorContainer
{
    private Dictionary<Type, Visitor.Visit> Visitors { get; } = new();
    private Visitor.Visit Default { get; set; } = default!;

    public void Register<TVisitee>(Visitor.Visit visitor)
    {
        Visitors[typeof(TVisitee)] = visitor;
    }

    public Visitor.Visit this[Type type] => Visitors.GetValueOrDefault(type, Default);
}

public class VisitorContainer<T>
{
    protected Dictionary<Type, Visitor.Visit<T>> Visitors { get; } = new();
    public Visitor.Visit<T> Default { get; set; } = default!;


    public VisitorContainer<T> Register<TVisitee>(Visitor.Visit<T> visitor)
    {
        Visitors[typeof(TVisitee)] = visitor;
        return this;
    }

    public Visitor.Visit<T> this[Type type] => Visitors.ContainsKey(type) ? Visitors[type] : Default;
}

public class VisitorContainer<TIn, TOut>
{
    protected Dictionary<Type, Visitor.Visit<TIn, TOut>> Visitors { get; } = new();
    public Visitor.Visit<TIn, TOut> Default { get; set; } = default!;

    public void Register<TVisitee>(Visitor.Visit<TIn, TOut> visitor)
    {
        Visitors[typeof(TVisitee)] = visitor;
    }

    public Visitor.Visit<TIn, TOut> this[Type type] => Visitors.ContainsKey(type) ? Visitors[type] : Default;
}