ParametersTokenizer.cs

using System;
using System.Collections.Generic;
using System.Reflection;
using System.Threading.Tasks;
using Waher.Persistence;
using Waher.Persistence.FullTextSearch;
using Waher.Persistence.FullTextSearch.Tokenizers;
using Waher.Persistence.Serialization;
using Waher.Runtime.Collections;
using Waher.Runtime.Inventory;
 
namespace Waher.Service.IoTBroker.Legal.Contracts.Tokenizers
{
    public class ParametersTokenizer : ITokenizer, IPropertyEvaluator
    {
        public ParametersTokenizer()
        {
        }
 
        public Grade Supports(Type Type)
        {
            if (typeInfo.IsAssignableFrom(Type))
                return Grade.Ok;
            else
                return Grade.NotAtAll;
        }
 
        private static readonly TypeInfo typeInfo = typeof(IEnumerable<Parameter>).GetTypeInfo();
 
        public async Task Tokenize(object Value, TokenizationProcess Process)
        {
            if (Value is IEnumerable<Parameter> Parameters)
                await Tokenize(Parameters, null, Process);
        }
 
        public static async Task Tokenize(IEnumerable<Parameter> Parameters,
            Contract Contract, TokenizationProcess Process)
        {
            if (!(Parameters is null))
            {
                foreach (Parameter Parameter in Parameters)
                {
                    await ParameterTokenizer.Tokenize(Parameter, Contract, Process);
                    Process.DocumentIndexOffset++;  // Make sure sequences of keywords don't cross element boundaries.
                }
            }
        }
 
        public Task Prepare(string Definition)
        {
            return Task.CompletedTask;
        }
 
        public async Task<object> Evaluate(object Instance)
        {
            if (Instance is Contract Contract)
                return Contract.Parameters;
            else if (Instance is GenericObject Obj)
            {
                if (Obj.TryGetFieldValue("Parameters", out object Obj2) &&
                    Obj2 is Array A)
                {
                    if (A.Length == 0)
                        return Array.Empty<Parameter>();
 
                    ChunkedList<Parameter> Parameters = new ChunkedList<Parameter>(A.Length);
 
                    foreach (object Item in A)
                    {
                        if (Item is GenericObject GenParameter &&
                            await Database.Specialize(GenParameter) is Parameter Parameter)
                        {
                            Parameters.Add(Parameter);
                        }
                        else if (Item is Parameter Parameter2)
                            Parameters.Add(Parameter2);
                    }
 
                    return Parameters;
                }
 
                return null;
            }
            else if (Instance is IEnumerable<Parameter> Parameters)
                return Parameters;
            else
                return null;
        }
    }
}