using System;
using System.Reactive;
using System.Reactive.Linq;
using DynamicData;
using Intromat.Model.Compiler;
using Intromat.ViewModels;
using NodeNetwork.Toolkit.ValueNode;
using NodeNetwork.ViewModels;

namespace Intromat.Nodes
{
    public abstract class ExecutionNodeBase : CodeGenNodeViewModel
    {
        protected readonly EndpointGroup _executionFlowGroup;

        protected ExecutionNodeBase(NodeType type)
            : base(type)
        {
            _executionFlowGroup = new EndpointGroup("Execution Flow");

            FlowOut = new CodeGenInputViewModel<IStatement>(EPortType.Execution)
            {
                Name = "Flow",
                Group = _executionFlowGroup
            };
            Inputs.Add(FlowOut);

            FlowOutChanged = FlowOut.ValueChanged.Select(_ => Unit.Default).StartWith(Unit.Default);
            
            FlowIn = new CodeGenOutputViewModel<IStatement>(EPortType.Execution)
            {
                Name = "Flow",
                Group = _executionFlowGroup
            };
            Outputs.Add(FlowIn);
        }

        public ValueNodeOutputViewModel<IStatement> FlowIn { get; }

        public ValueNodeInputViewModel<IStatement> FlowOut { get; }

        public IObservable<Unit> FlowOutChanged { get; }
    }
}