Mika Kolari

// INTERFACES

public interface ISingleCategorized
{
    Category Category { get; set; }
}

public interface IMultiCategorized
{
    IList<Category> Categories { get; set; }
}

public interface IPage
{
    int Id { get; }
    string Path { get; set; }
    IPage Parent { get; set; }
}

public interface ISearchablePage : IPage
{
    string SearchIndex { get; set; }
}

public interface ISingleCategorizedPage : IPage, ISingleCategorized
{
}

public interface IMultiCategorizedPage : IPage, IMultiCategorized
{
}


// ENTITY CLASSES

public abstract class Page : IPage
{
    public virtual int Id { get; set; }
    public virtual IPage Parent { get; set; }
    public virtual string Path { get; set; }

    [Searchable]
    public virtual string Title { get; set; }
}

public class Post : Page, ISearchablePage, IMultiCategorizedPage, IMultiTaggedPage
{
    [Searchable]
    public virtual string Text { get; set; }

    // IMultiCategorizedPage
    public virtual IList<Category> Categories { get; set; }
    // IMultiTaggedPage
    public virtual IList<Tag> Tags { get; set; }

    string ISearchablePage.SearchIndex { get; set; }

    public Post()
    {
        Categories = new List<Category>();
        Tags = new List<Tag>();
    }
}

public class Article : Page, ISearchablePage, ISingleCategorizedPage, IMultiTaggedPage
{
    [Searchable]
    public virtual string Text { get; set; }

    // ISingleCategorizedPage
    public virtual Category Category { get; set; }
    // IMultiTaggedPage
    public virtual IList<Tag> Tags { get; set; }

    string ISearchablePage.SearchIndex { get; set; }

    public Article()
    {
        Tags = new List<Tag>();
    }
}


// FLUENT NHIBERNATE MAPPING CLASSES

public class PageMapping : ClassMap<Page>
{
    public PageMapping()
    {
        Table("Page");
        Id(x => x.Id,"Id");
        References<Page>(x => x.Parent, "ParentId");
        Map(x => x.Path, "Path");
        Map(x => x.Title, "Title");

        DiscriminateSubClassesOnColumn("Type");
    }
}

public class PostMapping : SubclassMap<Post>
{
    public PostMapping()
    {
        Map(x => x.Text, "Text");
        // IMultiCategorizedPage
        HasManyToMany(x => x.Categories).Table("PageCategories").ParentKeyColumn("PageId").ChildKeyColumn("CategoryId").Cascade.SaveUpdate();
        // IMultiTaggedPage
        HasManyToMany(x => x.Tags).Table("PageTags").ParentKeyColumn("PageId").ChildKeyColumn("TagId").Cascade.SaveUpdate();
        // ISearchablePage
        Map(x => ((ISearchablePage)x).SearchIndex, "SearchIndex").LazyLoad();
    }
}
public class ArticleMapping : SubclassMap<Article>
{
    public ArticleMapping()
    {
        Map(x => x.Text, "Text");
        // ISingleCategorizedPage
        References(x => x.Category, "CategoryId");
        // IMultiTaggedPage
        HasManyToMany(x => x.Tags).Table("PageTags").ParentKeyColumn("PageId").ChildKeyColumn("TagId").Cascade.SaveUpdate();
        // ISearchablePage
        Map(x => ((ISearchablePage)x).SearchIndex, "SearchIndex").LazyLoad();
    }
}