/* 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 OpenSearch.Net;
using OpenSearch.Net.Utf8Json;
using OpenSearch.Net.Utf8Json.Resolvers;

namespace OpenSearch.Client
{
	internal class MultiSearchFormatter : IJsonFormatter<IMultiSearchRequest>
	{
		private const byte Newline = (byte)'\n';

		public IMultiSearchRequest Deserialize(ref JsonReader reader, IJsonFormatterResolver formatterResolver) =>
			DynamicObjectResolver.ExcludeNullCamelCase.GetFormatter<IMultiSearchRequest>().Deserialize(ref reader, formatterResolver);

		public void Serialize(ref JsonWriter writer, IMultiSearchRequest value, IJsonFormatterResolver formatterResolver)
		{
			if (value?.Operations == null)
				return;

			var settings = formatterResolver.GetConnectionSettings();
			var memoryStreamFactory = settings.MemoryStreamFactory;
			var serializer = settings.RequestResponseSerializer;

			foreach (var operation in value.Operations.Values)
			{
				var p = operation.RequestParameters;

				string GetString(string key) => p.GetResolvedQueryStringValue(key, settings);

				IUrlParameter indices = value.Index == null || !value.Index.Equals(operation.Index)
					? operation.Index
					: null;
				var operationIndex = indices?.GetString(settings);

				var searchType = GetString("search_type");
				if (searchType == "query_then_fetch")
					searchType = null;

				var header = new
				{
					index = operationIndex != value.Index ? operationIndex : null,
					search_type = searchType,
					preference = GetString("preference"),
					routing = GetString("routing"),
					ignore_unavailable = GetString("ignore_unavailable")
				};

				writer.WriteSerialized(header, serializer, settings, SerializationFormatting.None);
				writer.WriteRaw(Newline);
				writer.WriteSerialized(operation, serializer, settings, SerializationFormatting.None);
				writer.WriteRaw(Newline);
			}
		}
	}
}