using System;
using System.Collections.Generic;
using System.Linq;
using Microsoft.Dynamics.AX.Metadata.MetaModel;
using Microsoft.Dynamics.AX.Metadata.Storage;
using Microsoft.Dynamics.AX.Metadata.Storage.Runtime;
 
namespace DataEntityFields
{
    public class Demo
    {
        public static void Main(string[] args)
        {
            var environment = Microsoft.Dynamics.ApplicationPlatform.Environment.EnvironmentFactory.GetApplicationEnvironment();
            var runtimeConfiguration = new RuntimeProviderConfiguration(environment.Aos.PackageDirectory);
            var metadataProvider = new MetadataProviderFactory().CreateRuntimeProviderWithExtensions(runtimeConfiguration);
 
            AxDataEntityView entity = metadataProvider.DataEntityViews.Read("VendVendorV2Entity");
 
            foreach (AxDataEntityViewMappedField entityField in entity.Fields.Where(f => f is AxDataEntityViewMappedField))
            {
                var datasource = FindDataSource(entity.ViewMetadata.DataSources, entityField.DataSource);
                if (datasource == null)
                {
                    continue;
                }
 
                AxTable table = metadataProvider.Tables.Read(datasource.Table);
                AxTableField field = table.Fields[entityField.DataField];
                AxTableFieldString stringField = field as AxTableFieldString;
                if (stringField != null)
                {
                    AxEdtString edt = null;
                    if (stringField.ExtendedDataType != "")
                    {
                        edt = metadataProvider.Edts.Read(stringField.ExtendedDataType) as AxEdtString;
                    }
 
                    int stringSize = edt?.StringSize ?? stringField.StringSize;
                    Console.WriteLine($"{entityField.Name} (String {stringSize})");
                }
            }
 
            Console.ReadLine();
        }
 
        private static AxQuerySimpleDataSource FindDataSource(IEnumerable<AxQuerySimpleDatasource> dataSources, string dataSourceName)
        {
            foreach (AxQuerySimpleDataSource ds in dataSources)
            {
                if (ds.Name == dataSourceName)
                {
                    return ds;
                }
 
                return FindDataSource(ds.DataSources, dataSourceName);
            }
 
            return null;
        }
    }
}