Tz.cs

using System;
using System.Text;
using Waher.Content.Semantic.Model.Literals;
using Waher.Script;
using Waher.Script.Abstraction.Elements;
using Waher.Script.Exceptions;
using Waher.Script.Model;
 
namespace Waher.Content.Semantic.Functions
{
    public class Tz : FunctionOneSemanticVariable
    {
        public Tz(ScriptNode Argument, int Start, int Length, Expression Expression)
            : base(Argument, Start, Length, Expression)
        {
        }
 
        public override string FunctionName => nameof(Tz);
 
        public override IElement EvaluateScalar(ISemanticElement Argument, Variables Variables)
        {
            if (Argument.AssociatedObjectValue is DateTimeOffset TPO)
            {
                if (TPO.Offset == TimeSpan.Zero)
                    return new StringLiteral("Z");
                else
                {
                    StringBuilder sb = new StringBuilder();
 
                    if (TPO.Offset < TimeSpan.Zero)
                        sb.Append('-');
 
                    sb.Append(TPO.Offset.Hours.ToString("d2"));
                    sb.Append(':');
                    sb.Append(TPO.Offset.Minutes.ToString("d2"));
 
                    return new StringLiteral(sb.ToString());
                }
            }
            else if (Argument.AssociatedObjectValue is DateTime)
                return new StringLiteral(string.Empty);
            else
                throw new ScriptRuntimeException("Expected a Date and Time value.", this);
        }
    }
}