namespace locking
{
	public class LockTest
	{
		private ReaderWriterLockSlim m_lock = new();

		public void DoWork(int i)
		{
			Console.WriteLine($"{i}: DoWork()");
			m_lock.EnterUpgradeableReadLock();
			Console.WriteLine($"{i}: acquired read lock");
			try
			{
				Thread.Yield();
				Thread.Sleep(500);
				Thread.Yield();
				Console.WriteLine($"{i}: sleep complete");
				if (m_lock.TryEnterWriteLock(timeout: TimeSpan.FromMilliseconds(500)))
				{
					try
					{
						Console.WriteLine($"{i}: acquired write lock");
						Thread.Yield();
						Thread.Sleep(500);
						Thread.Yield();
					}
					finally
					{
						m_lock.ExitWriteLock();
						Console.WriteLine($"{i}: released write lock");
						Thread.Yield();
					}
				}
				else
				{
					Console.WriteLine($"{i}: failed to acquire write lock");
					Thread.Yield();
				}
			}
			finally
			{
				m_lock.ExitUpgradeableReadLock();
				Console.WriteLine($"{i}: released read lock");
			}
		}
	}

	internal class Program
	{

		static void Main(string[] args)
		{
			var lockTest = new LockTest();
			var tasks = Enumerable.Range(1, 10).Select(i => Task.Run(() => lockTest.DoWork(i))).ToArray();
			Task.WaitAll(tasks);
		}
	}
}