package se.despotify.util;
import se.despotify.Connection;
import se.despotify.client.protocol.command.media.LoadAlbum;
import se.despotify.client.protocol.command.media.LoadArtist;
import se.despotify.client.protocol.command.media.LoadTracks;
import se.despotify.client.protocol.command.media.playlist.LoadPlaylist;
import se.despotify.domain.Store;
import se.despotify.domain.media.*;
import se.despotify.exceptions.DespotifyException;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
*/
public class SpotifyURL {
public static final Pattern pattern = Pattern.compile("((http://open\\.spotify\\.com/)|(spotify:))(track|album|artist|(user[:/]+([^:/]+)[:/]playlist))[:/]+([A-Za-z0-9]+)");
public static enum URLtype {
spotifyURL, httpURL
}
public static interface Visitor<T> {
public T track(URLtype type, String URI);
public T album(URLtype type, String URI);
public T artist(URLtype type, String URI);
public T playlist(URLtype type, String user, String URI);
}
/**
* Lexical macthing for Spotify URL parts.
*
* @param URL URL to be matched.
* @param matcher Visitor to be triggered by this matching.
* @param <T> Visitor return type.
* @return Value as retuned by the executed matcher.
*/
public static <T> T match(String URL, Visitor<T> matcher) {
Matcher patternMatcher = pattern.matcher(URL);
if (!patternMatcher.matches()) {
throw new IllegalArgumentException("Not a valid URL: " + URL);
}
URLtype urlType = patternMatcher.group(2) != null ? URLtype.httpURL : URLtype.spotifyURL;
if (patternMatcher.group(5) != null) {
return matcher.playlist(urlType, patternMatcher.group(6), patternMatcher.group(7));
} else if ("track".equals(patternMatcher.group(4))) {
return matcher.track(urlType, patternMatcher.group(7));
} else if ("album".equals(patternMatcher.group(4))) {
return matcher.album(urlType, patternMatcher.group(7));
} else if ("artist".equals(patternMatcher.group(4))) {
return matcher.artist(urlType, patternMatcher.group(7));
} else {
throw new RuntimeException();
}
}
/**
* Browse a single instance of a domain object as represented by a Spotify URL.
*
* Use a {@link se.despotify.domain.media.Visitor visitor} on the {@link Visitable visitable} response rather than instanceof.
*
* @param URL A spotify URL, "http://open.spotify.com/..." or "spotify:...".
* @param connection service instance used to query for data.
* @return A visitable domain object representing parameter URL.
*/
public static Visitable browse(String URL, final Store store, final Connection connection) {
return match(URL, new Visitor<Visitable>(){
public Visitable track(URLtype type, String URI) {
Track track = store.getTrack(SpotifyURI.toHex(URI));
try {
new LoadTracks(store, track).send(connection.getProtocol());
} catch (DespotifyException e) {
throw new RuntimeException(e);
}
return track;
}
public Visitable album(URLtype type, String URI) {
Album album = store.getAlbum(SpotifyURI.toHex(URI));
try {
new LoadAlbum(store, album).send(connection.getProtocol());
} catch (DespotifyException e) {
throw new RuntimeException(e);
}
return album;
}
public Visitable artist(URLtype type, String URI) {
Artist artist = store.getArtist(SpotifyURI.toHex(URI));
try {
new LoadArtist(store, artist).send(connection.getProtocol());
} catch (DespotifyException e) {
throw new RuntimeException(e);
}
return artist;
}
public Visitable playlist(URLtype type, String user, String URI) {
Playlist playlist = store.getPlaylist(SpotifyURI.toHex(URI));
try {
new LoadPlaylist(store, playlist).send(connection.getProtocol());
} catch (DespotifyException e) {
throw new RuntimeException(e);
}
return playlist;
}
});
}
/**
* Transforms a spotify URL to a http URL and vice verse.
*
* SpotifyURL.match(URL, new URLtransformer());
*/
public static class URLtransformer implements Visitor<String> {
public String track(URLtype type, String URI) {
return type == URLtype.spotifyURL ? "http://open.spotify.com/track/" + URI : "spotify:track:" + URI;
}
public String album(URLtype type, String URI) {
return type == URLtype.spotifyURL ? "http://open.spotify.com/album/" + URI : "spotify:album:" + URI;
}
public String artist(URLtype type, String URI) {
return type == URLtype.spotifyURL ? "http://open.spotify.com/artist/" + URI : "spotify:artist:" + URI;
}
public String playlist(URLtype type, String user, String URI) {
return type == URLtype.spotifyURL ? "http://open.spotify.com/user/" + user + "/playlist/" + URI : "spotify:user:" + user + ":playlist:" + URI;
}
}
}