2 * Rhynodge - EpisodeFilter.java - Copyright © 2013 David Roden
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.
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.
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/>.
18 package net.pterodactylus.rhynodge.filters;
20 import static com.google.common.base.Optional.absent;
21 import static com.google.common.base.Preconditions.checkState;
22 import static com.google.common.collect.FluentIterable.from;
23 import static java.util.Arrays.asList;
25 import java.util.Collection;
26 import java.util.regex.Matcher;
27 import java.util.regex.Pattern;
29 import net.pterodactylus.rhynodge.Filter;
30 import net.pterodactylus.rhynodge.State;
31 import net.pterodactylus.rhynodge.states.EpisodeState;
32 import net.pterodactylus.rhynodge.states.EpisodeState.Episode;
33 import net.pterodactylus.rhynodge.states.FailedState;
34 import net.pterodactylus.rhynodge.states.TorrentState;
35 import net.pterodactylus.rhynodge.states.TorrentState.TorrentFile;
37 import com.google.common.base.Function;
38 import com.google.common.base.Optional;
39 import com.google.common.collect.HashMultimap;
40 import com.google.common.collect.Multimap;
43 * {@link Filter} implementation that extracts {@link Episode} information from
44 * the {@link TorrentFile}s contained in a {@link TorrentState}.
46 * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
48 public class EpisodeFilter implements Filter {
50 /** The pattern to parse episode information from the filename. */
51 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]"));
61 public State filter(State state) {
62 if (!state.success()) {
63 return FailedState.from(state);
65 checkState(state instanceof TorrentState, "state is not a TorrentState but a %s!", state.getClass());
67 TorrentState torrentState = (TorrentState) state;
68 final Multimap<Episode, TorrentFile> episodes = HashMultimap.create();
69 for (TorrentFile torrentFile : torrentState) {
70 Optional<Episode> episode = extractEpisode(torrentFile);
71 if (!episode.isPresent()) {
74 episodes.put(episode.get(), torrentFile);
77 return new EpisodeState(from(episodes.keySet()).transform(episodeFiller(episodes)).toSet());
85 * Returns a function that creates an {@link Episode} that contains all {@link
88 * @param episodeTorrents
89 * A multimap mapping episodes to torrent files.
90 * @return The function that performs the extraction of torrent files
92 private static Function<Episode, Episode> episodeFiller(final Multimap<Episode, TorrentFile> episodeTorrents) {
93 return new Function<Episode, Episode>() {
95 public Episode apply(Episode episode) {
96 Episode completeEpisode = new Episode(episode.season(), episode.episode());
97 for (TorrentFile torrentFile : episodeTorrents.get(episode)) {
98 completeEpisode.addTorrentFile(torrentFile);
100 return completeEpisode;
106 * Extracts episode information from the given torrent file.
109 * The torrent file to extract the episode information from
110 * @return The extracted episode information, or {@link Optional#absent()} if
111 * no episode information could be found
113 private static Optional<Episode> extractEpisode(TorrentFile torrentFile) {
114 for (Pattern episodePattern : episodePatterns) {
115 Matcher matcher = episodePattern.matcher(torrentFile.name());
116 if (!matcher.find() || matcher.groupCount() < 2) {
119 String seasonString = matcher.group(1);
120 String episodeString = matcher.group(2);
121 int season = Integer.valueOf(seasonString);
122 int episode = Integer.valueOf(episodeString);
123 return Optional.of(new Episode(season, episode));