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NHibernate 3D association with multiple meanings - how to focus on the map

I asked a similar question, but I gave up the idea that I had there to solve this problem, so I would like some help to help solve this in a neat way.

I have tables

Image - (Id, Name, RelativeFilePath)
ImageFilter - (Id, Type)
ImageContext - (Id, Name, ...)
ImageContextImage - (Id, ImageContextId, ImageId, ImageFilterId)

Sample data:

ImageContextImage      Id        ImageContextId         ImageId        ImageFilterId
                       1         1                      1              1
                       2         1                      1              2
                       3         2                      1              1
                       4         3                      2              1

As you can see, an image in context can have several filters.

All my entities are very simple except for this mapping above. I currently have

ImageContext
    public virtual int Id
    public virtual string Name
    public virtual IList<ImageContextImage> Images

ImageContextImage
    public virtual int Id
    public virtual ImageContext Context
    public virtual Image Image
    public virtual ImageFilter ImageFilter

, ImageContextImage. , ImageContextImage ImageFilter, . AsTernaryAssociation(), , , ! ?

? !

+3
1

, ( ). ImageContextImage , - . .

ImageContextImage:

public virtual int Id { get; set; }
public virtual Image Image { get; set; }
public virtual ImageContext Context { get; set; }
public virtual IList<ImageFilter> Filters { get; set; }

:

Id(x => x.Id);
References(x => x.Image);
References(x => x.Context);
HasManyToMany(x => x.Filters); // filters are referenced via many-to-many relation

ImageContext:

public virtual int Id { get; set; }
public virtual string Name { get; set; }
public virtual IList<ImageContextImage> ImageContextImageList { get; set; }

:

Id(x => x.Id);
Map(x => x.Name);
HasMany(x => x.ImageContextImageList)
    .Inverse(); // to aggregate all ImageContextImage that are fererencing this instnstance of ImageContext
    .KeyColumn("Context_id");

:

ImageContextImage(Id, Image_id, Context_id)

"--" :

ImageFilterToImageContextImage(ImageContextImage_id, ImageFilter_id)

, . , :) - , .

AsTernaryAssociation, . , :).

EDIT: ( ), - ImageContextImage, :

public class ImageContext
{
    public virtual int Id { get; set; }
    public virtual string Name { get; set; }
    public virtual IList<ImageContextImage> ImageContextImageList { get; set; }

    public ImageContext()
    {
        ImageContextImageList = new List<ImageContextImage>();
    }
}

public class ImageContextMap : ClassMap<ImageContext>
{
    public ImageContextMap()
    {
        Id(x => x.Id);
        Map(x => x.Name);
        HasMany(x => x.ImageContextImageList).Component(c =>
        {
            c.References(x => x.Image);
            c.References(x => x.Filter);
        }).Cascade.AllDeleteOrphan();
    }
}

public class ImageContextImage
{
    public virtual Image Image { get; set; }
    public virtual ImageFilter Filter { get; set; }
}

ImageContext , :

public virtual IEnumerable<Image> AssociatedImages
{
    get
    {
        return ImageContextImageList.Select(x => x.Image).Distinct().ToList();
    }
}

public virtual IEnumerable<ImageFilter> GetFilters(Image image)
{
    return ImageContextImageList.Where(x => x.Image == image).Select(x => x.Filter).ToList();
}

AsTernaryAssociation.

+2

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