Tree View

var sitesAndPostsByUser = Given<User>.Match((user, facts) =>
    from site in facts.OfType<Site>()
    where site.creator == user
    where !facts.Any<SiteDeleted>(
        sd => sd.site == site &&
        !facts.Any<SiteRestored>(sr => sr.deleted == sd))
    select new
    {
        Site = site,
        Names =
            from name in facts.OfType<SiteName>()
            where name.site == site
            where !facts.Any<SiteName>(next => next.prior.Contains(name))
            select name.value,
        Domains =
            from domain in facts.OfType<SiteDomain>()
            where domain.site == site
            where !facts.Any<SiteDomain>(next => next.prior.Contains(domain))
            select domain.value,
        Posts =
            from post in facts.OfType<Post>()
            where post.site == site
            where !facts.Any<PostDeleted>(pd => pd.post == post &&
                !facts.Any<PostRestored>(pr => pr.deleted == pd))
            select new
            {
                Post = post,
                Title =
                    from title in facts.OfType<PostTitle>()
                    where title.post == post
                    where !facts.Any<PostTitle>(next => next.prior.Contains(title))
                    select title.value
            }
    });

var sitesAndPosts = await jinagaClient.Query(sitesAndPostsByUser, user);

sitesAndPosts

var sitesAndPostsViewModel = sitesAndPosts.Select(s => new
{
    Name = s.Names.FirstOrDefault() ?? "New site",
    Domain = s.Domains.FirstOrDefault() ?? "",
    Posts = s.Posts.Select(p => new
    {
        Title = p.Title.FirstOrDefault() ?? "New post"
    })
});

sitesAndPostsViewModel