/* 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.Extensions;
using OpenSearch.Net.Utf8Json;
using OpenSearch.Net.Utf8Json.Internal;


namespace OpenSearch.Client
{
	internal class FuzzinessInterfaceFormatter : IJsonFormatter<IFuzziness>
	{
		public void Serialize(ref JsonWriter writer, IFuzziness value, IJsonFormatterResolver formatterResolver)
		{
			if (value == null)
			{
				writer.WriteNull();
				return;
			}

			if (value.Auto)
			{
				if (!value.Low.HasValue || !value.High.HasValue)
					writer.WriteString("AUTO");
				else
					writer.WriteString($"AUTO:{value.Low},{value.High}");
			}
			else if (value.EditDistance.HasValue)
				writer.WriteInt32(value.EditDistance.Value);
			else if (value.Ratio.HasValue)
				writer.WriteDouble(value.Ratio.Value);
			else
				writer.WriteNull();
		}

		public IFuzziness Deserialize(ref JsonReader reader, IJsonFormatterResolver formatterResolver)
		{
			var formatter = formatterResolver.GetFormatter<Fuzziness>();
			return formatter.Deserialize(ref reader, formatterResolver);
		}
	}

	internal class FuzzinessFormatter : IJsonFormatter<Fuzziness>
	{
		private static readonly byte[] AutoBytes = JsonWriter.GetEncodedPropertyNameWithoutQuotation("AUTO");

		public Fuzziness Deserialize(ref JsonReader reader, IJsonFormatterResolver formatterResolver)
		{
			var token = reader.GetCurrentJsonToken();

			switch (token) {
				case JsonToken.String:
				{
					var rawAuto = reader.ReadStringSegmentUnsafe();
					if (rawAuto.EqualsBytes(AutoBytes))
						return Fuzziness.Auto;

					var colonIndex = -1;
					var commaIndex = -1;
					for (var i = AutoBytes.Length; i < rawAuto.Count; i++)
					{
						// ReSharper disable once PossibleNullReferenceException
						if (rawAuto.Array[rawAuto.Offset + i] == (byte)':')
							colonIndex = rawAuto.Offset + i;
						else if (rawAuto.Array[rawAuto.Offset + i] == (byte)',')
						{
							commaIndex = rawAuto.Offset + i;
							break;
						}
					}

					var low = NumberConverter.ReadInt32(rawAuto.Array, colonIndex + 1, out _);
					var high = NumberConverter.ReadInt32(rawAuto.Array, commaIndex + 1, out _);
					return Fuzziness.AutoLength(low, high);
				}
				case JsonToken.Number:
				{
					var value = reader.ReadNumberSegment();

					if (value.IsDouble())
					{
						var ratio = NumberConverter.ReadDouble(value.Array, value.Offset, out _);
						return Fuzziness.Ratio(ratio);
					}
					else
					{
						var editDistance = NumberConverter.ReadInt32(value.Array, value.Offset, out _);
						return Fuzziness.EditDistance(editDistance);
					}
				}
				default:
					reader.ReadNextBlock();
					return null;
			}
		}

		public void Serialize(ref JsonWriter writer, Fuzziness value, IJsonFormatterResolver formatterResolver)
		{
			var formatter = formatterResolver.GetFormatter<IFuzziness>();
			formatter.Serialize(ref writer, value, formatterResolver);
		}
	}
}