ProjectZ/Assets/Scripts/TaskManager.cs

using UnityEngine;
using System.Collections;

// https://github.com/krockot/Unity-TaskManager/blob/master/TaskManager.cs
namespace Koptilnya
{
    public class Task
    {
        /// Returns true if and only if the coroutine is running.  Paused tasks
        /// are considered to be running.
        public bool Running
        {
            get { return task.Running; }
        }

        /// Returns true if and only if the coroutine is currently paused.
        public bool Paused
        {
            get { return task.Paused; }
        }

        /// Delegate for termination subscribers.  manual is true if and only if
        /// the coroutine was stopped with an explicit call to Stop().
        public delegate void FinishedHandler(bool manual);

        /// Termination event.  Triggered when the coroutine completes execution.
        public event FinishedHandler Finished;

        /// Creates a new Task object for the given coroutine.
        ///
        /// If autoStart is true (default) the task is automatically started
        /// upon construction.
        public Task(IEnumerator c, bool autoStart = true)
        {
            task = TaskManager.CreateTask(c);
            task.Finished += TaskFinished;
            if (autoStart)
                Start();
        }

        /// Begins execution of the coroutine
        public void Start()
        {
            task.Start();
        }

        /// Discontinues execution of the coroutine at its next yield.
        public void Stop()
        {
            task.Stop();
        }

        public void Pause()
        {
            task.Pause();
        }

        public void Unpause()
        {
            task.Unpause();
        }

        void TaskFinished(bool manual)
        {
            FinishedHandler handler = Finished;
            if (handler != null)
                handler(manual);
        }

        TaskManager.TaskState task;
    }

    class TaskManager : MonoBehaviour
    {
        public class TaskState
        {
            public bool Running
            {
                get { return running; }
            }

            public bool Paused
            {
                get { return paused; }
            }

            public delegate void FinishedHandler(bool manual);

            public event FinishedHandler Finished;

            IEnumerator coroutine;
            bool running;
            bool paused;
            bool stopped;

            public TaskState(IEnumerator c)
            {
                coroutine = c;
            }

            public void Pause()
            {
                paused = true;
            }

            public void Unpause()
            {
                paused = false;
            }

            public void Start()
            {
                running = true;
                singleton.StartCoroutine(CallWrapper());
            }

            public void Stop()
            {
                stopped = true;
                running = false;
            }

            IEnumerator CallWrapper()
            {
                yield return null;
                IEnumerator e = coroutine;
                while (running)
                {
                    if (paused)
                        yield return null;
                    else
                    {
                        if (e != null && e.MoveNext())
                        {
                            yield return e.Current;
                        }
                        else
                        {
                            running = false;
                        }
                    }
                }

                FinishedHandler handler = Finished;
                if (handler != null)
                    handler(stopped);
            }
        }

        static TaskManager singleton;

        public static TaskState CreateTask(IEnumerator coroutine)
        {
            if (singleton == null)
            {
                GameObject go = new GameObject("TaskManager");
                singleton = go.AddComponent<TaskManager>();
            }

            return new TaskState(coroutine);
        }
    }
}