/* 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
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*  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
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*/

using System;
using System.Collections.Generic;
using OpenSearch.Net.Utf8Json;

namespace OpenSearch.Client
{
	[JsonFormatter(typeof(VerbatimDictionaryKeysFormatter<Tokenizers, ITokenizers, string, ITokenizer>))]
	public interface ITokenizers : IIsADictionary<string, ITokenizer> { }

	public class Tokenizers : IsADictionaryBase<string, ITokenizer>, ITokenizers
	{
		public Tokenizers() { }

		public Tokenizers(IDictionary<string, ITokenizer> container) : base(container) { }

		public Tokenizers(Dictionary<string, ITokenizer> container) : base(container) { }

		public void Add(string name, ITokenizer analyzer) => BackingDictionary.Add(name, analyzer);
	}

	public class TokenizersDescriptor : IsADictionaryDescriptorBase<TokenizersDescriptor, ITokenizers, string, ITokenizer>
	{
		public TokenizersDescriptor() : base(new Tokenizers()) { }

		public TokenizersDescriptor UserDefined(string name, ITokenizer analyzer) => Assign(name, analyzer);

		/// <summary>
		/// A tokenizer of type edgeNGram.
		/// </summary>
		public TokenizersDescriptor EdgeNGram(string name, Func<EdgeNGramTokenizerDescriptor, IEdgeNGramTokenizer> selector) =>
			Assign(name, selector?.Invoke(new EdgeNGramTokenizerDescriptor()));

		/// <summary>
		/// A tokenizer of type nGram.
		/// </summary>
		public TokenizersDescriptor NGram(string name, Func<NGramTokenizerDescriptor, INGramTokenizer> selector) =>
			Assign(name, selector?.Invoke(new NGramTokenizerDescriptor()));

		/// <summary>
		/// A tokenizer of type keyword that emits the entire input as a single input.
		/// </summary>
		public TokenizersDescriptor Keyword(string name, Func<KeywordTokenizerDescriptor, IKeywordTokenizer> selector) =>
			Assign(name, selector?.Invoke(new KeywordTokenizerDescriptor()));

		/// <summary>
		/// A tokenizer of type letter that divides text at non-letters. That’s to say, it defines tokens as maximal strings of
		/// adjacent letters.
		/// <para>
		/// Note, this does a decent job for most European languages, but does a terrible job for some Asian languages, where words
		/// are not
		/// separated by spaces.
		/// </para>
		/// </summary>
		public TokenizersDescriptor Letter(string name, Func<LetterTokenizerDescriptor, ILetterTokenizer> selector) =>
			Assign(name, selector?.Invoke(new LetterTokenizerDescriptor()));

		/// <summary>
		/// A tokenizer of type lowercase that performs the function of Letter Tokenizer and Lower Case Token Filter together.
		/// <para>It divides text at non-letters and converts them to lower case. </para>
		/// <para>While it is functionally equivalent to the combination of Letter Tokenizer and Lower Case Token Filter, </para>
		/// <para>there is a performance advantage to doing the two tasks at once, hence this (redundant) implementation.</para>
		/// </summary>
		public TokenizersDescriptor Lowercase(string name, Func<LowercaseTokenizerDescriptor, ILowercaseTokenizer> selector) =>
			Assign(name, selector?.Invoke(new LowercaseTokenizerDescriptor()));

		/// <summary>
		///  The path_hierarchy tokenizer takes something like this:
		/// <para>/something/something/else</para>
		/// <para>And produces tokens:</para>
		/// <para></para>
		/// <para>/something</para>
		/// <para>/something/something</para>
		/// <para>/something/something/else</para>
		/// </summary>
		public TokenizersDescriptor PathHierarchy(string name, Func<PathHierarchyTokenizerDescriptor, IPathHierarchyTokenizer> selector) =>
			Assign(name, selector?.Invoke(new PathHierarchyTokenizerDescriptor()));

		/// <summary>
		/// A tokenizer of type pattern that can flexibly separate text into terms via a regular expression.
		/// </summary>
		public TokenizersDescriptor Pattern(string name, Func<PatternTokenizerDescriptor, IPatternTokenizer> selector) =>
			Assign(name, selector?.Invoke(new PatternTokenizerDescriptor()));

		/// <summary>
		/// A tokenizer of type standard providing grammar based tokenizer that is a good tokenizer for most European language
		/// documents.
		/// <para>The tokenizer implements the Unicode Text Segmentation algorithm, as specified in Unicode Standard Annex #29.</para>
		/// </summary>
		public TokenizersDescriptor Standard(string name, Func<StandardTokenizerDescriptor, IStandardTokenizer> selector = null) =>
			Assign(name, selector.InvokeOrDefault(new StandardTokenizerDescriptor()));

		/// <summary>
		/// A tokenizer of type uax_url_email which works exactly like the standard tokenizer, but tokenizes emails and urls as
		/// single tokens
		/// </summary>
		public TokenizersDescriptor UaxEmailUrl(string name, Func<UaxEmailUrlTokenizerDescriptor, IUaxEmailUrlTokenizer> selector) =>
			Assign(name, selector?.Invoke(new UaxEmailUrlTokenizerDescriptor()));

		/// <summary>
		/// A tokenizer of type whitespace that divides text at whitespace.
		/// </summary>
		public TokenizersDescriptor Whitespace(string name, Func<WhitespaceTokenizerDescriptor, IWhitespaceTokenizer> selector = null) =>
			Assign(name, selector.InvokeOrDefault(new WhitespaceTokenizerDescriptor()));

		/// <summary>
		/// A tokenizer of type pattern that can flexibly separate text into terms via a regular expression.
		/// Part of the `analysis-kuromoji` plugin:
		///
		/// </summary>
		public TokenizersDescriptor Kuromoji(string name, Func<KuromojiTokenizerDescriptor, IKuromojiTokenizer> selector) =>
			Assign(name, selector?.Invoke(new KuromojiTokenizerDescriptor()));

		/// <summary>
		/// Tokenizes text into words on word boundaries, as defined in UAX #29: Unicode Text Segmentation. It behaves much
		/// like the standard tokenizer, but adds better support for some Asian languages by using a dictionary-based approach
		/// to identify words in Thai, Lao, Chinese, Japanese, and Korean, and using custom rules to break Myanmar and Khmer
		/// text into syllables.
		/// Part of the `analysis-icu` plugin:
		/// </summary>
		public TokenizersDescriptor Icu(string name, Func<IcuTokenizerDescriptor, IIcuTokenizer> selector) =>
			Assign(name, selector?.Invoke(new IcuTokenizerDescriptor()));

		/// <inheritdoc cref="INoriTokenizer" />
		public TokenizersDescriptor Nori(string name, Func<NoriTokenizerDescriptor, INoriTokenizer> selector) =>
			Assign(name, selector?.Invoke(new NoriTokenizerDescriptor()));

		/// <inheritdoc cref="ICharGroupTokenizer.TokenizeOnCharacters" />
		/// >
		public TokenizersDescriptor CharGroup(string name, Func<CharGroupTokenizerDescriptor, ICharGroupTokenizer> selector) =>
			Assign(name, selector?.Invoke(new CharGroupTokenizerDescriptor()));
	}
}