CaseInsensitiveStringCollectionTokenizer.cs

using System;
using System.Collections.Generic;
using System.Reflection;
using System.Threading.Tasks;
using Waher.Runtime.Inventory;
 
namespace Waher.Persistence.FullTextSearch.Tokenizers
{
    public class CaseInsensitiveStringCollectionTokenizer : ITokenizer
    {
        public CaseInsensitiveStringCollectionTokenizer()
        {
        }
 
        public Grade Supports(Type Type)
        {
            if (typeInfo.IsAssignableFrom(Type))
                return Grade.Ok;
            else
                return Grade.NotAtAll;
        }
 
        private static readonly TypeInfo typeInfo = typeof(IEnumerable<CaseInsensitiveString>).GetTypeInfo();
 
        public Task Tokenize(object Value, TokenizationProcess Process)
        {
            if (Value is IEnumerable<CaseInsensitiveString> Strings)
            {
                foreach (CaseInsensitiveString cis in Strings)
                {
                    StringTokenizer.Tokenize(cis.LowerCase, Process);
                    Process.DocumentIndexOffset++;  // Make sure sequences of keywords don't cross element boundaries.
                }
            }
 
            return Task.CompletedTask;
        }
 
    }
}