package com.github.hakko.musiccabinet.parser.lastfm;
import static com.github.hakko.musiccabinet.parser.lastfm.ScrobbledTracksHandler.State.ALBUM;
import static com.github.hakko.musiccabinet.parser.lastfm.ScrobbledTracksHandler.State.ARTIST;
import static com.github.hakko.musiccabinet.parser.lastfm.ScrobbledTracksHandler.State.NAME;
import static com.github.hakko.musiccabinet.parser.lastfm.ScrobbledTracksHandler.State.PLAY_COUNT;
import static com.github.hakko.musiccabinet.parser.lastfm.ScrobbledTracksHandler.State.TRACK;
import static org.apache.commons.lang.math.NumberUtils.toInt;
import static org.apache.commons.lang.math.NumberUtils.toShort;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;
import com.github.hakko.musiccabinet.domain.model.library.TrackPlayCount;
import com.github.hakko.musiccabinet.domain.model.music.Artist;
import com.github.hakko.musiccabinet.domain.model.music.Track;
public class ScrobbledTracksHandler extends DefaultHandler {
private short page;
private short totalPages;
private List<TrackPlayCount> trackPlayCounts = new ArrayList<>();
private TrackPlayCount currentTrackPlayCount; // used internally while parsing
private State scope; // stores if we're currently reading a track or an artist
private State state; // stores state based on latest encountered start tag
private StringBuilder characterData; // used to assemble xml text passed by parser
// maps start tag to respective state, for tags where we read xml text() data
private static Map<String, State> xmlToStateMap = new HashMap<>();
private static final String TAG_TRACKS = "tracks";
private static final String ATTR_PAGE = "page";
private static final String ATTR_TOTAL_PAGES = "totalPages";
private static final String TAG_ARTIST = "artist";
private static final String TAG_ALBUM = "album";
private static final String TAG_TRACK = "track";
private static final String TAG_NAME = "name";
private static final String TAG_PLAY_COUNT = "playcount";
static {
xmlToStateMap.put(TAG_NAME, NAME);
xmlToStateMap.put(TAG_PLAY_COUNT, PLAY_COUNT);
}
enum State {
ARTIST, ALBUM, TRACK, NAME, PLAY_COUNT;
}
@Override
public void startElement(String uri, String localName, String qName, Attributes attributes)
throws SAXException {
if (TAG_TRACKS.equals(qName)) {
page = toShort(attributes.getValue(ATTR_PAGE));
totalPages = toShort(attributes.getValue(ATTR_TOTAL_PAGES));
} else if (TAG_TRACK.equals(qName)) {
scope = TRACK;
currentTrackPlayCount = new TrackPlayCount();
currentTrackPlayCount.setTrack(new Track());
currentTrackPlayCount.getTrack().setArtist(new Artist());
} else if (TAG_ALBUM.equals(qName)) {
scope = ALBUM;
} else if (TAG_ARTIST.equals(qName)) {
scope = ARTIST;
} else {
state = xmlToStateMap.get(qName);
if (state != null) {
characterData = new StringBuilder();
}
}
}
@Override
public void endElement(String uri, String localName, String qName)
throws SAXException {
if (state != null) {
String chars = characterData.toString();
if (state == NAME) {
if (scope == TRACK) {
currentTrackPlayCount.getTrack().setName(chars);
} else if (scope == ARTIST) {
currentTrackPlayCount.getTrack().getArtist().setName(chars);
}
} else if (state == PLAY_COUNT) {
currentTrackPlayCount.setPlayCount(toInt(chars));
}
state = null;
}
if (TAG_TRACK.equals(qName)) {
trackPlayCounts.add(currentTrackPlayCount);
}
}
@Override
public void characters(char[] ch, int start, int length) throws SAXException {
if (state != null) {
characterData.append(ch, start, length);
}
}
/* Variables to be exposured after parsing */
public short getPage() {
return page;
}
public short getTotalPages() {
return totalPages;
}
public List<TrackPlayCount> getTrackPlayCounts() {
return trackPlayCounts;
}
}