using Antlr4.Runtime;
using Rubberduck.Parsing.Abstract;
using System;
using System.Collections.Generic;

namespace Rubberduck.Parsing.Expressions
{
    public sealed class EmptyValue : IValue
    {
        public static readonly EmptyValue Value = new EmptyValue();

        public ValueType ValueType
        {
            get
            {
                return ValueType.Empty;
            }
        }

        public bool AsBool
        {
            get
            {
                return false;
            }
        }

        public byte AsByte
        {
            get
            {
                return 0;
            }
        }

        public DateTime AsDate
        {
            get
            {
                return new DateTime(1899, 12, 30);
            }
        }

        public decimal AsDecimal
        {
            get
            {
                return 0;
            }
        }

        public string AsString
        {
            get
            {
                return string.Empty;
            }
        }

        public IEnumerable<IToken> AsTokens
        {
            get
            {
                return new List<IToken>();
            }
        }

        public override string ToString()
        {
            return "<Empty>";
        }
    }
}
