EventReference.cs

using System.Threading.Tasks;
using System.Xml;
using Waher.Content.Xml;
using Waher.Persistence.Attributes;
using Waher.Service.IoTBroker.NeuroFeatures;
using Waher.Service.IoTBroker.StateMachines.EventHandlers;
using Waher.Service.IoTBroker.StateMachines.Exceptions;
using Waher.Service.IoTBroker.StateMachines.Model.Attributes;
using Waher.Service.IoTBroker.StateMachines.Model.States;
 
namespace Waher.Service.IoTBroker.StateMachines.Model.Events
{
    public class EventReference : EventNode
    {
        private ScriptableStringAttribute eventRef;
 
        public EventReference()
            : base()
        {
        }
 
        [DefaultValueNull]
        public string EventReferenceDefinition
        {
            get => this.eventRef?.Definition;
            set => this.eventRef = new ScriptableStringAttribute(value, this);
        }
 
        public override Task Parse(XmlElement Xml)
        {
            this.eventRef = new ScriptableStringAttribute(XML.Attribute(Xml, "eventRef"), this);
 
            return base.Parse(Xml);
        }
 
        public override string LocalName => nameof(EventReference);
 
        public override IStateMachineNode Create()
        {
            return new EventReference();
        }
 
        public override void CheckReferences(StateMachine Machine, Token Token)
        {
            if (this.eventRef.IsConstant && !Machine.TryGetEvent(this.eventRef.Definition, out _))
                throw new StateMachineException(Machine, "Event not found: " + this.eventRef.Definition);
 
            base.CheckReferences(Machine, Token);
        }
 
        public async Task<Event> GetReference(EvaluationArguments Arguments)
        {
            if (this.eventRef is null)
                throw new StateMachineException(Arguments.Machine, "No event id defined.");
 
            string EventId = await this.eventRef.Evaluate(Arguments.Variables);
            if (!Arguments.Machine.TryGetEvent(EventId, out Event Event))
                throw new StateMachineException(Arguments.Machine, "Event not found: " + Event.Id);
 
            return Event;
        }
 
        public override async Task<EventHandlerReference> Register(int EventIndex, EvaluationArguments Arguments, OnEvent Event)
        {
            Event Event2 = await this.GetReference(Arguments);
            return await Event2.Register(EventIndex, Arguments, Event);
        }
 
        public override async Task Unregister(int EventIndex, EvaluationArguments Arguments)
        {
            Event Event = await this.GetReference(Arguments);
            await Event.Unregister(EventIndex, Arguments);
        }
 
        public override string Label => this.eventRef.Definition;
 
    }
}