src/main/java/net/pterodactylus/rhynodge/filters/EpisodeFilter.java

   1 /*
   2  * Rhynodge - EpisodeFilter.java - Copyright © 2013 David Roden
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 package net.pterodactylus.rhynodge.filters;
  19
  20 import static com.google.common.base.Optional.absent;
  21 import static com.google.common.base.Preconditions.checkState;
  22 import static java.util.Arrays.asList;
  23
  24 import java.util.HashMap;
  25 import java.util.Map;
  26 import java.util.Collection;
  27 import java.util.regex.Matcher;
  28 import java.util.regex.Pattern;
  29
  30 import net.pterodactylus.rhynodge.Filter;
  31 import net.pterodactylus.rhynodge.State;
  32 import net.pterodactylus.rhynodge.states.EpisodeState;
  33 import net.pterodactylus.rhynodge.states.EpisodeState.Episode;
  34 import net.pterodactylus.rhynodge.states.FailedState;
  35 import net.pterodactylus.rhynodge.states.TorrentState;
  36 import net.pterodactylus.rhynodge.states.TorrentState.TorrentFile;
  37
  38 import com.google.common.base.Optional;
  39
  40 /**
  41  * {@link Filter} implementation that extracts {@link Episode} information from
  42  * the {@link TorrentFile}s contained in a {@link TorrentState}.
  43  *
  44  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  45  */
  46 public class EpisodeFilter implements Filter {
  47
  48         /** The pattern to parse episode information from the filename. */
  49         private static final Collection<Pattern> episodePatterns = asList(Pattern.compile("[Ss](\\d{2})[Ee](\\d{2})"), Pattern.compile("[^\\d](\\d{1,2})x(\\d{2})[^\\d]"));
  50
  51         //
  52         // FILTER METHODS
  53         //
  54
  55         /**
  56          * {@inheritDoc}
  57          */
  58         @Override
  59         public State filter(State state) {
  60                 if (!state.success()) {
  61                         return FailedState.from(state);
  62                 }
  63                 checkState(state instanceof TorrentState, "state is not a TorrentState but a %s!", state.getClass());
  64
  65                 TorrentState torrentState = (TorrentState) state;
  66                 Map<Episode, Episode> episodes = new HashMap<Episode, Episode>();
  67                 for (TorrentFile torrentFile : torrentState) {
  68                         Optional<Episode> episode = extractEpisode(torrentFile);
  69                         if (!episode.isPresent()) {
  70                                 continue;
  71                         }
  72                         if (!episodes.containsKey(episode.get())) {
  73                                 episodes.put(episode.get(), episode.get());
  74                         }
  75                         episodes.get(episode.get()).addTorrentFile(torrentFile);
  76                 }
  77
  78                 return new EpisodeState(episodes.values());
  79         }
  80
  81         //
  82         // STATIC METHODS
  83         //
  84
  85         /**
  86          * Extracts episode information from the given torrent file.
  87          *
  88          * @param torrentFile
  89          *              The torrent file to extract the episode information from
  90          * @return The extracted episode information, or {@link Optional#absent()} if
  91          *         no episode information could be found
  92          */
  93         private static Optional<Episode> extractEpisode(TorrentFile torrentFile) {
  94                 for (Pattern episodePattern : episodePatterns) {
  95                         Matcher matcher = episodePattern.matcher(torrentFile.name());
  96                         if (!matcher.find() || matcher.groupCount() < 2) {
  97                                 continue;
  98                         }
  99                         String seasonString = matcher.group(1);
 100                         String episodeString = matcher.group(2);
 101                         int season = Integer.valueOf(seasonString);
 102                         int episode = Integer.valueOf(episodeString);
 103                         return Optional.of(new Episode(season, episode));
 104                 }
 105                 return absent();
 106         }
 107
 108 }