using Dapper;
using NzbDrone.Core.Datastore;

namespace NzbDrone.Core.Housekeeping.Housekeepers
{
    public class CleanupOrphanedMetadataFiles : IHousekeepingTask
    {
        private readonly IMainDatabase _database;

        public CleanupOrphanedMetadataFiles(IMainDatabase database)
        {
            _database = database;
        }

        public void Clean()
        {
            DeleteOrphanedByArtist();
            DeleteOrphanedByAlbum();
            DeleteOrphanedByTrackFile();
            DeleteWhereAlbumIdIsZero();
            DeleteWhereTrackFileIsZero();
        }

        private void DeleteOrphanedByArtist()
        {
            using (var mapper = _database.OpenConnection())
            {
                mapper.Execute(@"DELETE FROM ""MetadataFiles""
                                     WHERE ""Id"" IN (
                                     SELECT ""MetadataFiles"".""Id"" FROM ""MetadataFiles""
                                     LEFT OUTER JOIN ""Artists""
                                     ON ""MetadataFiles"".""ArtistId"" = ""Artists"".""Id""
                                     WHERE ""Artists"".""Id"" IS NULL)");
            }
        }

        private void DeleteOrphanedByAlbum()
        {
            using (var mapper = _database.OpenConnection())
            {
                mapper.Execute(@"DELETE FROM ""MetadataFiles""
                                     WHERE ""Id"" IN (
                                     SELECT ""MetadataFiles"".""Id"" FROM ""MetadataFiles""
                                     LEFT OUTER JOIN ""Albums""
                                     ON ""MetadataFiles"".""AlbumId"" = ""Albums"".""Id""
                                     WHERE ""MetadataFiles"".""AlbumId"" > 0
                                     AND ""Albums"".""Id"" IS NULL)");
            }
        }

        private void DeleteOrphanedByTrackFile()
        {
            using (var mapper = _database.OpenConnection())
            {
                mapper.Execute(@"DELETE FROM ""MetadataFiles""
                                     WHERE ""Id"" IN (
                                     SELECT ""MetadataFiles"".""Id"" FROM ""MetadataFiles""
                                     LEFT OUTER JOIN ""TrackFiles""
                                     ON ""MetadataFiles"".""TrackFileId"" = ""TrackFiles"".""Id""
                                     WHERE ""MetadataFiles"".""TrackFileId"" > 0
                                     AND ""TrackFiles"".""Id"" IS NULL)");
            }
        }

        private void DeleteWhereAlbumIdIsZero()
        {
            using (var mapper = _database.OpenConnection())
            {
                mapper.Execute(@"DELETE FROM ""MetadataFiles""
                                     WHERE ""Id"" IN (
                                     SELECT ""Id"" FROM ""MetadataFiles""
                                     WHERE ""Type"" IN (4, 6)
                                     AND ""AlbumId"" = 0)");
            }
        }

        private void DeleteWhereTrackFileIsZero()
        {
            using (var mapper = _database.OpenConnection())
            {
                mapper.Execute(@"DELETE FROM ""MetadataFiles""
                                     WHERE ""Id"" IN (
                                     SELECT ""Id"" FROM ""MetadataFiles""
                                     WHERE ""Type"" IN (2, 5)
                                     AND ""TrackFileId"" = 0)");
            }
        }
    }
}