using Lucene.Net.Analysis.Standard;
using Lucene.Net.Index;
using Lucene.Net.Search;
using Lucene.Net.Store;
using Lucene.Net.Documents;
using Lucene.Net.Util;

public class LuceneExample
{
    private static readonly string indexPath = "C:\\LuceneIndex";

    public static void CreateIndex()
    {
        using var directory = FSDirectory.Open(indexPath);
        var analyzer = new StandardAnalyzer(LuceneVersion.LUCENE_48);
        var indexConfig = new IndexWriterConfig(LuceneVersion.LUCENE_48, analyzer);
        using var writer = new IndexWriter(directory, indexConfig);

        var doc = new Document
        {
            new TextField("title", "Lucene for .NET", Field.Store.YES),
            new TextField("content", "Lucene is a search library for .NET.", Field.Store.YES)
        };
        writer.AddDocument(doc);
        writer.Flush(triggerMerge: false, applyAllDeletes: false);
    }

    public static void SearchIndex(string queryText)
    {
        using var directory = FSDirectory.Open(indexPath);
        using var reader = DirectoryReader.Open(directory);
        var searcher = new IndexSearcher(reader);

        var analyzer = new StandardAnalyzer(LuceneVersion.LUCENE_48);
        var queryParser = new QueryParser(LuceneVersion.LUCENE_48, "content", analyzer);
        var query = queryParser.Parse(queryText);

        var hits = searcher.Search(query, 10).ScoreDocs;
        foreach (var hit in hits)
        {
            var foundDoc = searcher.Doc(hit.Doc);
            Console.WriteLine($"Found: {foundDoc.Get("title")}");
        }
    }
}

using Nest;

public class ElasticsearchExample
{
    private static readonly Uri node = new Uri("http://localhost:9200");
    private static readonly ConnectionSettings settings = new ConnectionSettings(node).DefaultIndex("documents");
    private static readonly ElasticClient client = new ElasticClient(settings);

    public static void IndexDocument()
    {
        var document = new
        {
            Id = 1,
            Title = "Elasticsearch for .NET",
            Content = "Elasticsearch is a distributed search engine."
        };
        
        var indexResponse = client.IndexDocument(document);
        Console.WriteLine($"Index Success: {indexResponse.IsValid}");
    }

    public static void SearchDocument(string queryText)
    {
        var searchResponse = client.Search<dynamic>(s => s
            .Query(q => q
                .Match(m => m
                    .Field(f => f.Content)
                    .Query(queryText)
                )
            )
        );

        foreach (var hit in searchResponse.Hits)
        {
            Console.WriteLine($"Found: {hit.Source.Title}");
        }
    }
}

using SolrNet;
using SolrNet.Commands.Parameters;

public class SolrExample
{
    private static readonly ISolrOperations<Product> solr = ServiceLocator.Current.GetInstance<ISolrOperations<Product>>();

    public static void IndexDocument()
    {
        var product = new Product
        {
            Id = "1",
            Title = "Solr for .NET",
            Description = "Solr is a powerful search platform."
        };
        solr.Add(product);
        solr.Commit();
    }

    public static void SearchDocument(string queryText)
    {
        var results = solr.Query(new SolrQueryByField("description", queryText), new QueryOptions
        {
            Rows = 10
        });

        foreach (var result in results)
        {
            Console.WriteLine($"Found: {result.Title}");
        }
    }
}

public class Product
{
    public string Id { get; set; }
    public string Title { get; set; }
    public string Description { get; set; }
}