InvokeExtension

using UnityEngine;
using System.Collections;
using System;


namespace OddTales.Framework.Core.ClassExtension
{
    /// <summary>
    /// Invoke methods of MonoBehaviour call other methods by name. 
    /// Methods called by name is hard to track in code (you cannot find "Usages")
    /// It is easy to roll out your own Invoke using Coroutines
    /// Code based on : http://www.gamasutra.com/blogs/HermanTulleken/20160812/279100/50_Tips_and_Best_Practices_for_Unity_2016_Edition.php
    /// Warnings : slower than string Invoke + memory allocation (use GetEnumerator to cache Coroutine if you can)
    /// </summary>
    public static class InvokeExtension
    {
        /// <summary>
        /// Example of use : this.Invoke(ShootEnemy); //where ShootEnemy is a parameterless void method.
        /// You can also invoke methods with parameters : this.Invoke(() => AdditionMethod(5, 8), 4)
        /// </summary>
        public static Coroutine Invoke(this MonoBehaviour monoBehaviour, Action action, float time)
        {
            if (time.Equals(0)) return monoBehaviour.StartCoroutine(InvokeCoroutine(action, null));
            else return monoBehaviour.StartCoroutine(InvokeCoroutine(action, new WaitForSeconds(time)));
        }

        /// <summary> You can cache WaitForSeconds in your code to reduce memory allocation </summary>
        public static Coroutine Invoke(this MonoBehaviour monoBehaviour, Action action, WaitForSeconds time)
        {
            return monoBehaviour.StartCoroutine(InvokeCoroutine(action, time));
        }

        /// <summary> You can cache enumerator using GetEnumerator method to remove all memory allocation at Invoke time</summary>
        public static Coroutine Invoke(this MonoBehaviour monoBehaviour, IEnumerator enumerator)
        {
            return monoBehaviour.StartCoroutine(enumerator);
        }

        /// <summary> Cache enumerator to avoid any memory allocation during Invoke </summary>
        public static IEnumerator GetEnumerator(Action action, float time)
        {
            return time.Equals(0) ? GetEnumerator(action, null) : GetEnumerator(action, new WaitForSeconds(time));
        }

        /// <summary> Cache enumerator to avoid any memory allocation during Invoke </summary>
        public static IEnumerator GetEnumerator(Action action, WaitForSeconds time)
        {
            return InvokeCoroutine(action, time);
        }

        private static IEnumerator InvokeCoroutine(Action action, WaitForSeconds time)
        {
            if (time != null) yield return time;
            if (action != null) action.Invoke();
        }
    }
}