NHibernateSchemaReader.cs

using System.Collections.Generic;
using System.Linq;
using LINQPad.Extensibility.DataContext;
using NHibernate;
using NHibernate.Metadata;
using NHibernate.Type;

namespace NHPad
{
    public static class NHibernateSchemaReader
    {
        public static List<ExplorerItem> GetSchema(ISessionFactory sessionFactory)
        {
            var items = sessionFactory.GetAllClassMetadata().Values
                .Select(x => new ExplorerItem(x.EntityName, ExplorerItemKind.QueryableObject, ExplorerIcon.Table)
                                 {
                                     Children = x.PropertyNames.Select(p => GetPropertyItem(x, p)).ToList(),
                                     Tag = x.GetMappedClass(EntityMode.Poco)
                                 }).ToList();
            foreach (var property in items.SelectMany(x => x.Children))
            {
                var type = (IType)property.Tag;
                var manyToOne = type as ManyToOneType;
                if (manyToOne != null)
                    property.HyperlinkTarget = items.Single(x => Equals(x.Tag, type.ReturnedClass));
            }
            return items;
        }

        private static ExplorerItem GetPropertyItem(IClassMetadata classMetadata, string propertyName)
        {
            return new ExplorerItem(string.Format("{0}", propertyName),
                                    GetKind(classMetadata, propertyName),
                                    GetIcon(classMetadata, propertyName))
                       {
                           Tag = classMetadata.GetPropertyType(propertyName)
                       };
        }

        static ExplorerItemKind GetKind(IClassMetadata classMetadata, string propertyName)
        {
            var propertyType = classMetadata.GetPropertyType(propertyName);
            return propertyType.IsCollectionType
                       ? ExplorerItemKind.CollectionLink
                       : propertyType.IsAssociationType
                             ? ExplorerItemKind.ReferenceLink
                             : ExplorerItemKind.Property;
        }

        static ExplorerIcon GetIcon(IClassMetadata classMetadata, string propertyName)
        {
            var propertyType = classMetadata.GetPropertyType(propertyName);
            return propertyType.IsCollectionType
                       ? ExplorerIcon.OneToMany
                       : propertyType.IsAssociationType
                             ? ExplorerIcon.ManyToOne
                             : ExplorerIcon.Column;
        }
    }
}