public async Task <List <Track> > GrabAndSaveTracks(TracksCriteria criteria)
{
TracksSource tracksSource = await _tracksSourceRepository.GetRandomTracksSource(criteria);
List <Track> tracks = await _grabber.GrabRandomTracks(tracksSource);
await _tracksRepository.SaveTracks(tracks);
return(tracks);
}
public async Task <List <Track> > GetTracks(TracksCriteria criteria, int lastId = 0)
{
List <Track> tracks = await _tracksRepository.GetTracks(criteria, 5, lastId);
if (tracks.Count == 0)
{
return(await GrabAndSaveTracks(criteria));
}
return(tracks);
}
public async Task <TracksSource> GetRandomTracksSource(TracksCriteria criteria)
{
var query = from ts in _db.TracksSources select ts;
foreach (string[] tagsGroup in criteria.TagsGroups)
{
query = query.Where(ts => ts.Tags.Any(t => tagsGroup.Contains(t)));
}
int count = await query.CountAsync();
int offset = RandomUtils.GetRandomFromInterval(0, count);
query = query.OrderBy(ts => ts.Id).Skip(offset);
return(await query.FirstOrDefaultAsync());
}
public async Task <List <Track> > GetTracks(string tempos, string genres, int lastId = 0)
{
TracksCriteria criteria = new TracksCriteria(tempos, genres);
// todo: use something like middleware for it
string clientId = Request.Cookies["clientId"];
if (clientId == null)
{
clientId = Guid.NewGuid().ToString();
CookieOptions options = new CookieOptions();
options.Expires = DateTime.Now.AddYears(100);
Response.Cookies.Append("clientId", clientId, options);
}
_backgroundTracksLoadingList.AddCriteria(clientId, criteria);
return(await _tracksProvider.GetTracks(criteria, lastId));
}
public async Task <List <Track> > GetTracks(TracksCriteria tracksCriteria, int maxCount = 5, int lastId = 0)
{
var now = DateTime.Now;
var query = _db.Tracks.Where(t => t.ExpirationDatetime > now);
if (lastId > 0)
{
query = query.Where(t => t.Id > lastId).OrderBy(t => t.Id);
}
else
{
query = query.OrderByDescending(t => t.Id);
}
foreach (string[] tagsGroup in tracksCriteria.TagsGroups)
{
query = query.Where(t => t.TracksSource.Tags.Any(t => tagsGroup.Contains(t)));
}
query = query.Take(maxCount);
return(await query.ToListAsync());
}
public void AddCriteria(string clientId, TracksCriteria criteria)
{
_criteriasByClients[clientId] = criteria.GetRandomMinimalCriteria().ToString();
}