/* SPDX-License-Identifier: Apache-2.0
*
* The OpenSearch Contributors require contributions made to
* this file be licensed under the Apache-2.0 license or a
* compatible open source license.
*/
/*
* Modifications Copyright OpenSearch Contributors. See
* GitHub history for details.
*
*  Licensed to Elasticsearch B.V. under one or more contributor
*  license agreements. See the NOTICE file distributed with
*  this work for additional information regarding copyright
*  ownership. Elasticsearch B.V. licenses this file to you under
*  the Apache License, Version 2.0 (the "License"); you may
*  not use this file except in compliance with the License.
*  You may obtain a copy of the License at
*
* 	http://www.apache.org/licenses/LICENSE-2.0
*
*  Unless required by applicable law or agreed to in writing,
*  software distributed under the License is distributed on an
*  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
*  KIND, either express or implied.  See the License for the
*  specific language governing permissions and limitations
*  under the License.
*/

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using OpenSearch.Net.Extensions;

namespace OpenSearch.Net
{
	public class SniffingConnectionPool : StaticConnectionPool
	{
		private readonly ReaderWriterLockSlim _readerWriter = new ReaderWriterLockSlim();

		public SniffingConnectionPool(IEnumerable<Uri> uris, bool randomize = true, IDateTimeProvider dateTimeProvider = null)
			: base(uris, randomize, dateTimeProvider) { }

		public SniffingConnectionPool(IEnumerable<Node> nodes, bool randomize = true, IDateTimeProvider dateTimeProvider = null)
			: base(nodes, randomize, dateTimeProvider) { }

		public SniffingConnectionPool(IEnumerable<Node> nodes, Func<Node, float> nodeScorer, IDateTimeProvider dateTimeProvider = null)
			: base(nodes, nodeScorer, dateTimeProvider) { }

		/// <inheritdoc />
		public override IReadOnlyCollection<Node> Nodes
		{
			get
			{
				try
				{
					//since internalnodes can be changed after returning we return
					//a completely new list of cloned nodes
					_readerWriter.EnterReadLock();
					return InternalNodes.Select(n => n.Clone()).ToList();
				}
				finally
				{
					_readerWriter.ExitReadLock();
				}
			}
		}

		/// <inheritdoc />
		public override bool SupportsPinging => true;

		/// <inheritdoc />
		public override bool SupportsReseeding => true;

		/// <inheritdoc />
		public override void Reseed(IEnumerable<Node> nodes)
		{
			if (!nodes.HasAny(out var nodesArray)) return;

			try
			{
				_readerWriter.EnterWriteLock();
				var sortedNodes = SortNodes(nodesArray)
					.DistinctBy(n => n.Uri)
					.ToList();

				InternalNodes = sortedNodes;
				GlobalCursor = -1;
				LastUpdate = DateTimeProvider.Now();
			}
			finally
			{
				_readerWriter.ExitWriteLock();
			}
		}

		/// <inheritdoc />
		public override IEnumerable<Node> CreateView(Action<AuditEvent, Node> audit = null)
		{
			_readerWriter.EnterReadLock();
			try
			{
				return base.CreateView(audit);
			}
			finally
			{
				_readerWriter.ExitReadLock();
			}
		}

		protected override void DisposeManagedResources()
		{
			_readerWriter?.Dispose();
			base.DisposeManagedResources();
		}
	}
}