using System;

namespace Umbraco.Cms.Core
{
    /// <summary>
    /// Abstract implementation of managed IDisposable.
    /// </summary>
    /// <remarks>
    /// This is for objects that do NOT have unmanaged resources.
    ///
    /// Can also be used as a pattern for when inheriting is not possible.
    ///
    /// See also: https://msdn.microsoft.com/en-us/library/b1yfkh5e%28v=vs.110%29.aspx
    /// See also: https://lostechies.com/chrispatterson/2012/11/29/idisposable-done-right/
    ///
    /// Note: if an object's ctor throws, it will never be disposed, and so if that ctor
    /// has allocated disposable objects, it should take care of disposing them.
    /// </remarks>
    public abstract class DisposableObjectSlim : IDisposable
    {
        /// <summary>
        /// Gets a value indicating whether this instance is disposed.
        /// </summary>
        /// <remarks>
        /// for internal tests only (not thread safe)
        /// </remarks>
        public bool Disposed { get; private set; }

        /// <summary>
        /// Disposes managed resources
        /// </summary>
        protected abstract void DisposeResources();

        /// <summary>
        /// Disposes managed resources
        /// </summary>
        /// <param name="disposing">True if disposing via Dispose method and not a finalizer. Always true for this class.</param>
        protected virtual void Dispose(bool disposing)
        {
            if (!Disposed)
            {
                if (disposing)
                {
                    DisposeResources();
                }

                Disposed = true;
            }
        }

        /// <inheritdoc/>
#pragma warning disable CA1063 // Implement IDisposable Correctly
        public void Dispose() => Dispose(disposing: true); // We do not use GC.SuppressFinalize because this has no finalizer
#pragma warning restore CA1063 // Implement IDisposable Correctly
    }
}