using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleAppLevel2Class
{
    public class ResourceManager
    {
        // Simulate handlers / pointers

        private IntPtr resourceHandle; // unmanaged resource
        private bool isDisposed = false; // placeholder to see the status of the unmanaged resource

        public ResourceManager() // constructor for ResourceManager Class
          // construct data
        {
            resourceHandle = (IntPtr)123456; // "unmanaged" memory space
            Console.WriteLine("Unmanaged allocated resource " + resourceHandle);
        }



        // Implement IDisposable Interface
        public void Dispose()
        {
            Dispose(true);
            GC.SuppressFinalize(this); // Prevent finanlizer from running if successful
        
        } // IDisposable

        // Make the implementation of Dispose protected
        // public private protected
        protected virtual void Dispose(bool disposing)
        {
            // nested if 1. do we need to run Finalizer 2. If we do need to run it, what handlers are marked to be disposed

            if (!isDisposed)
            { // true

                if (disposing)
                {
                    // Free other managed objects
                                    
                } // disposing

                // free unmanaged objects
                if (resourceHandle != IntPtr.Zero)
                {
                    Console.WriteLine("Unmanged memory released. ");
                    resourceHandle = IntPtr.Zero;
                
                }

                isDisposed = true;
            
            } // (!isDisposed)
        
        } // Dispose()


        // Dispose of the unmanaged resource
        // Finalizer
        ~ResourceManager()
        {
            // Disposable Method return bool
            // true dispose of the unmanaged handle
            // false it leaves it in memory
            Dispose(false);

        } // Finalizer

    } // Resource Manager

} // ns