private IEnumerable <SongRecommendationDto> GetSimilar(SongDetailsDto currentSong, string userId, int maxCount)
{
var songRecommendations = _graphClient.Cypher
.Match("(song:Song)-[CATEGORIZED_BY]->(songCategory:SongCategory)")
.Where((SongCategory songCategory) => songCategory.Id == currentSong.SongCategory.Id)
.AndWhere((Song song) => song.Id != currentSong.Song.Id)
.Match("(song)-[COMPOSED_BY]->(artist:Artist)")
.Match("(targetSong:Song)")
.Where((Song targetSong) => targetSong.Id == currentSong.Song.Id)
.OptionalMatch("(song)-[ri:CONTAINS]->(instrument:Instrument)<-[:CONTAINS]-(targetSong)")
.OptionalMatch("(song)-[rt:DESCRIBED_BY]->(tag:Tag)<-[:DESCRIBED_BY]-(targetSong)")
.OptionalMatch("(user:User)-[LIKES]->(song)")
.Where((User user) => user.Id != userId)
.ReturnDistinct((song, artist, instrument, tag, user) => new SongRecommendationDto
{
Song = song.As <Song>(),
Artist = artist.As <Artist>(),
CommonInstruments = instrument.CountDistinct(),
CommonTags = tag.CountDistinct(),
NumberOfLikes = user.Count()
})
.Results
.OrderByDescending(ComputeRecommendationScore)
.Take(maxCount);
return(songRecommendations);
}
public static SongItemModel ToSongItemModel(SongDetailsDto songDetails)
{
if (songDetails == null)
{
return(null);
}
return(new SongItemModel
{
Id = songDetails.Song.Id,
Name = songDetails.Song.Title,
Artist = ArtistMapper.ToArtistModel(songDetails.Artist)
});
}
public static SongModel ToSongModel(SongDetailsDto songDetails)
{
if (songDetails == null)
{
return(null);
}
return(new SongModel
{
Id = songDetails.Song.Id,
Name = songDetails.Song.Title,
Url = songDetails.Song.Url,
Artist = ArtistMapper.ToArtistModel(songDetails.Artist),
SongCategory = SongCategoryMapper.ToSongCategoryModel(songDetails.SongCategory),
//TODO: Have a look over here
Tags = songDetails.Tags.GroupBy(t => t.Id).Select(grp => TagMapper.ToTagModel(grp.FirstOrDefault())),
Instruments = songDetails.Instruments.GroupBy(i => i.Id).Select(grp => InstrumentMapper.ToInstrumentModel(grp.FirstOrDefault()))
});
}
