Events

using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public enum EventsID
{
    Reset,
    ChooseItem,
    PerformAction
}

public class EventManager
{
    // Generic callback
    #region PublicDelegate
    public delegate void Callback();
    public delegate void Callback<T>(T arg1);
    #endregion
    //public delegate void Callback<T, U>(T arg1, U arg2);

    private static Dictionary<EventsID, Delegate> eventsDictionary = new Dictionary<EventsID, Delegate>();

    //take event id in input
    public static void TriggerEvent(EventsID InEventID)
    {
        //if there is event with id key
        if (eventsDictionary.ContainsKey(InEventID))
        {
            //invoke as CallBack without input
            (eventsDictionary[InEventID] as Callback).Invoke();
        }
    }

    //take event id and method input as input
    public static void TriggerEvent<T>(EventsID InEventID, T InVariable)
    {
        //if there is event with id key
        if (eventsDictionary.ContainsKey(InEventID))
        {
            //invoke as CallBack with input
            (eventsDictionary[InEventID] as Callback<T>).Invoke(InVariable);
        }
    }

    //call this method to add event without input
    public static void StartListening(EventsID InEventID, Callback listener)
    {
        //check if ther is dictionary with correct key
        if (!eventsDictionary.ContainsKey(InEventID))
        {
            //if there isn't add event
            eventsDictionary.Add(InEventID, listener);
        }

        else
        {
            //take delegate, cast it ass callbakc and add callback (use this to check if signature as equal)
            eventsDictionary[InEventID] = (Callback)eventsDictionary[InEventID] + listener;
        }

    }
    //call this method to add event without input
    public static void StartListening<T>(EventsID InEventID, Callback<T> listener)
    {
        //check if ther is dictionary with correct key
        if (!eventsDictionary.ContainsKey(InEventID))
        {
            //if there isn't add event
            eventsDictionary.Add(InEventID, listener);
        }

        else
        {
            //take delegate, cast it ass callbakc and add callback (use this to check if signature as equal)
            eventsDictionary[InEventID] = (Callback<T>)eventsDictionary[InEventID] + listener;
        }
    }

    //call this method to remove event without input
    public static void StopListening(EventsID InEventID, Callback listener)
    {
        //if dictionary containt key
        if (eventsDictionary.ContainsKey(InEventID))
        {
            //take delegate, cast it ass callbakc and remove callback (use this to check if signature as equal)
            eventsDictionary[InEventID] = (Callback)eventsDictionary[InEventID] - listener;

            //ask alessia
            eventsDictionary.Remove(InEventID);
        }
    }

    //call this method to remove event with one input input
    public static void StopListening<T>(EventsID InEventID, Callback<T> listener)
    {
        //if dictionary containt key
        if (eventsDictionary.ContainsKey(InEventID))
        {
            //take delegate, cast it ass callbakc and remove callback (use this to check if signature as equal)
            eventsDictionary[InEventID] = (Callback<T>)eventsDictionary[InEventID] - listener;
            //ask alessia
            eventsDictionary.Remove(InEventID);
        }
    }
}