Wait.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Threading.Tasks;
using Waher.Script;
 
namespace TAG.Simulator.ObjectModel.Activities
{
    public class Wait : ActivityNode
    {
        private readonly List<ITriggerNode> triggers = new List<ITriggerNode>();
        private Timeout timeout = null;
 
        public Wait(ISimulationNode Parent, Model Model)
            : base(Parent, Model)
        {
        }
 
        public override string LocalName => nameof(Wait);
 
        public override ISimulationNode Create(ISimulationNode Parent, Model Model)
        {
            return new Wait(Parent, Model);
        }
 
        public void Register(ITriggerNode Node)
        {
            if (Node is Timeout Timeout)
            {
                if (this.timeout is null)
                    this.timeout = Timeout;
                else
                    throw new Exception("A timeout has already been defined.");
            }
            else
                this.triggers.Add(Node);
        }
 
        public override async Task<LinkedListNode<IActivityNode>> Execute(Variables Variables)
        {
            int i, c = this.triggers.Count;
            if (c == 0)
                throw new Exception("No triggers defined.");
 
            int d = c;
 
            if (!(this.timeout is null))
                d++;
 
            Task[] Tasks = new Task[d];
 
            for (i = 0; i < c; i++)
                Tasks[i] = this.triggers[i].GetTask();
 
            if (!(this.timeout is null))
                Tasks[c] = this.timeout.GetTask();
 
            Task Result = await Task.WhenAny(Tasks);
            i = Array.IndexOf<Task>(Tasks, Result);
 
            if (i < 0)
                throw new Exception("Unexpected error.");
 
            if (i < c)
                await this.triggers[i].Execute(Variables);
            else
                await this.timeout.Execute(Variables);
 
            return null;
        }
 
        public override void ExportPlantUml(StreamWriter Output, int Indentation, char QuoteChar)
        {
            Indent(Output, Indentation);
            Output.WriteLine(":Wait for first:;");
            Indent(Output, Indentation);
 
            bool First = true;
 
            foreach (ITriggerNode Node in this.triggers)
            {
                Node.ExportPlantUml(Output, Indentation, First, QuoteChar);
                First = false;
            }
 
            if (!First)
            {
                Indent(Output, Indentation);
                Output.WriteLine("end split");
            }
        }
 
    }
}