using System;

namespace JiShe.CollectBus.Common.Extensions
{
    /// <summary>
    /// Extension methods to make locking easier.
    /// </summary>
    public static class LockExtensions
    {
        /// <summary>
        /// Executes given <paramref name="action"/> by locking given <paramref name="source"/> object.
        /// </summary>
        /// <param name="source">Source object (to be locked)</param>
        /// <param name="action">Action (to be executed)</param>
        public static void Locking(this object source, Action action)
        {
            lock (source)
            {
                action();
            }
        }

        /// <summary>
        /// Executes given <paramref name="action"/> by locking given <paramref name="source"/> object.
        /// </summary>
        /// <typeparam name="T">Type of the object (to be locked)</typeparam>
        /// <param name="source">Source object (to be locked)</param>
        /// <param name="action">Action (to be executed)</param>
        public static void Locking<T>(this T source, Action<T> action) where T : class
        {
            lock (source)
            {
                action(source);
            }
        }

        /// <summary>
        /// Executes given <paramref name="func"/> and returns it's value by locking given <paramref name="source"/> object.
        /// </summary>
        /// <typeparam name="TResult">Return type</typeparam>
        /// <param name="source">Source object (to be locked)</param>
        /// <param name="func">Function (to be executed)</param>
        /// <returns>Return value of the <paramref name="func"/></returns>
        public static TResult Locking<TResult>(this object source, Func<TResult> func)
        {
            lock (source)
            {
                return func();
            }
        }

        /// <summary>
        /// Executes given <paramref name="func"/> and returns it's value by locking given <paramref name="source"/> object.
        /// </summary>
        /// <typeparam name="T">Type of the object (to be locked)</typeparam>
        /// <typeparam name="TResult">Return type</typeparam>
        /// <param name="source">Source object (to be locked)</param>
        /// <param name="func">Function (to be executed)</param>
        /// <returns>Return value of the <paramnref name="func"/></returns>
        public static TResult Locking<T, TResult>(this T source, Func<T, TResult> func) where T : class
        {
            lock (source)
            {
                return func(source);
            }
        }
    }
}