public AlbumIndexViewModel(Chinook.Repository.IMusicRepository musicRepository, int page, int pageSize = 5)
        {
            PageSize = pageSize;

            var albums = musicRepository.GetAlbums();
            int totalRows = albums.Count();
            int totalPages = (int)Math.Ceiling((double)totalRows / pageSize);

            int currentPage = page;
            if (currentPage < 1) currentPage = 1;
            if (currentPage > totalPages) currentPage = totalPages;

            int startRow = (currentPage - 1) * pageSize;

            CurrentPage = currentPage;
            TotalPages = totalPages;
            NextPage = currentPage < totalPages ? currentPage + 1 : (int?)null;
            PreviousPage = currentPage > 1 ? currentPage - 1 : (int?)null;
            StartingRow = startRow + 1;
            
            Albums =
                from a in albums.OrderBy(x => x.AlbumID).Skip(startRow).Take(pageSize)
                select new AlbumViewModel
                {
                    AlbumID = a.AlbumID,
                    Title = a.Title,
                    Artist = musicRepository.GetArtists().Where(x => x.ID == a.ArtistID).Select(x => x.Name).FirstOrDefault(),
                };
        }
        public AlbumSearchViewModel(string phrase, Chinook.Repository.IMusicRepository musicRepository)
        {
            phrase = phrase.ToLower();

            var artists = musicRepository.GetArtists().ToArray();

            var artistQuery =
                from x in artists
                select x;
            if (!String.IsNullOrWhiteSpace(phrase))
            {
                artistQuery =
                    from x in artistQuery
                    where x.Name.ToLower().Contains(phrase)
                    select x;
            }

            var artistIDs =
                (from x in artistQuery
                 select x.ID).ToArray();

            var query =
                from x in musicRepository.GetAlbums()
                where artistIDs.Contains(x.ArtistID)
                select x;

            if (!String.IsNullOrWhiteSpace(phrase))
            {
                var query2 =
                    from x in musicRepository.GetAlbums()
                    where x.Title.ToLower().Contains(phrase)
                    select x;
                query = query.Union(query2);
            }

            var albums = query.Distinct();
            Albums =
                from a in albums
                select new AlbumViewModel
                {
                    AlbumID = a.AlbumID,
                    Title = a.Title,
                    Artist = artists.Where(x => x.ID == a.ArtistID).Select(x => x.Name).FirstOrDefault(),
                };
        }