/* 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.IO;
using System.Runtime.InteropServices;
using OpenSearch.Stack.ArtifactsApi;
using OpenSearch.Stack.ArtifactsApi.Products;

namespace OpenSearch.OpenSearch.Managed.FileSystem
{
	/// <inheritdoc />
	public class NodeFileSystem : INodeFileSystem
	{
		protected const string SubFolder = "OpenSearchManaged";

		public NodeFileSystem(OpenSearchVersion version, string openSearchHome = null)
		{
			Version = version;
			Artifact = version.Artifact(Product.OpenSearch);
			LocalFolder = AppDataFolder(version);
			OpenSearchHome = openSearchHome ??
			                    GetOpenSearchHomeVariable() ?? throw new ArgumentNullException(nameof(openSearchHome));

			ConfigEnvironmentVariableName = "OPENSEARCH_PATH_CONF";
		}

		protected OpenSearchVersion Version { get; }
		protected Artifact Artifact { get; }

		private static bool IsMono { get; } = Type.GetType("Mono.Runtime") != null;

		protected static string BinarySuffix => IsMono || Path.DirectorySeparatorChar == '/' ? "" : ".bat";

		/// <inheritdoc />
		public string Binary
		{
			get
			{
				if (Artifact.ServerType == ServerType.OpenSearch)
					return Path.Combine(OpenSearchHome, "bin", "opensearch") + BinarySuffix;
				return Path.Combine(OpenSearchHome, "bin", "elasticsearch") + BinarySuffix;
			}
		}

		/// <inheritdoc />
		public string PluginBinary
		{
			get
			{
				if (Artifact.ServerType == ServerType.OpenSearch)
					return Path.Combine(OpenSearchHome, "bin", "opensearch-plugin") + BinarySuffix;
				return Path.Combine(OpenSearchHome, "bin", "elasticsearch-plugin") + BinarySuffix;
			}
		}

		/// <inheritdoc />
		public string OpenSearchHome { get; }

		/// <inheritdoc />
		public string LocalFolder { get; }

		/// <inheritdoc />
		public virtual string ConfigPath => null;

		/// <inheritdoc />
		public virtual string DataPath => null;

		/// <inheritdoc />
		public virtual string LogsPath => null;

		/// <inheritdoc />
		public virtual string RepositoryPath => null;

		public string ConfigEnvironmentVariableName { get; }

		protected static string AppDataFolder(OpenSearchVersion version)
		{
			var appData = GetApplicationDataDirectory();
			return Path.Combine(appData, SubFolder, version.Artifact(Product.OpenSearch).LocalFolderName);
		}

		protected static string GetOpenSearchHomeVariable() => Environment.GetEnvironmentVariable("OPENSEARCH_HOME");

		protected static string GetApplicationDataDirectory() =>
			RuntimeInformation.IsOSPlatform(OSPlatform.Windows)
				? Environment.GetEnvironmentVariable("LocalAppData")
				: Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData,
					Environment.SpecialFolderOption.Create);
	}
}