using System.Collections.Generic;

namespace Ariadne.UnitTests
{
    /// <summary>
    /// Keeps a local of its type parameter across a pause.
    /// </summary>
    public partial class Collector<T> : Arc<ArcTests.Gates>
    {
        public T Source;

        public T Result;

        protected override void Run(ArcTests.Gates gates)
        {
            T held = Source;
            var seen = new List<T>();

        wait:
            while (!gates.Open.Contains("go"))
            {
                seen.Add(held);
                Yield();
            }

            seen.Add(held);
            Result = seen[seen.Count - 1];
            Count = seen.Count;
        }

        public int Count;
    }

    /// <summary>
    /// Holds a passage whose parameter and local are of its type parameter.
    /// </summary>
    public abstract partial class Stepper<T> : Arc<ArcTests.Gates>
    {
        public T Last;

        protected void Hold(ArcTests.Gates gates, T value)
        {
            T held = value;

        hold:
            while (!gates.Open.Contains("go"))
            {
                Yield();
            }

            Last = held;
        }
    }

    public partial class WordStepper : Stepper<string>
    {
        public string Source = "word";

        protected override void Run(ArcTests.Gates gates)
        {
            string local = Source + "!";

        first:
            Hold(gates, local);
        }
    }

    /// <summary>
    /// Offers a passage for other arcs to run, in a class with a type parameter.
    /// </summary>
    public partial class Planter<T> : Arc<ArcTests.Gates>
    {
        public T Planted;

        public void Plant(ArcTests.Gates gates, T seed)
        {
            T kept = seed;

        grow:
            while (!gates.Open.Contains("go"))
            {
                Yield();
            }

            Planted = kept;
        }

        protected override void Run(ArcTests.Gates gates)
        {
        }
    }

    public partial class Gardener : Arc<ArcTests.Gates>
    {
        public Planter<string> Plot;

        public string Report;

        protected override void Run(ArcTests.Gates gates)
        {
            string seed = "tulip";

        plant:
            Plot.Plant(gates, seed);
            Report = "planted " + Plot.Planted;
        }
    }
}