GenericWebLyricsProvider.java

/*
 *  Jajuk
 *  Copyright (C) The Jajuk Team
 *  http://jajuk.info
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License
 *  as published by the Free Software Foundation; either version 2
 *  of the License, or any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *  
 */
package org.jajuk.services.lyrics.providers;

import ext.services.network.NetworkUtils;

import java.net.MalformedURLException;
import java.net.URL;

import org.jajuk.base.File;
import org.jajuk.base.Track;
import org.jajuk.util.Const;
import org.jajuk.util.DownloadManager;
import org.jajuk.util.log.Log;

/**
 * GenericProvider is a basic processor for web-based lyrics providers. It
 * doesn't provide fine-grained processing and simply retrieves raw text data
 * from HTML pages.
 * 
 * The GenericProvider is used as a base class by other, more fine-grained
 * specific providers.
 */
public abstract class GenericWebLyricsProvider implements ILyricsProvider {
  private String source = null;
  private String queryUrlTemplate = null;
  /** audio file we search lyrics for. */
  File audioFile = null;

  /**
   * Instantiates a new generic web lyrics provider.
   * 
   * @param queryUrlTemplate 
   */
  public GenericWebLyricsProvider(final String queryUrlTemplate) {
    this.queryUrlTemplate = queryUrlTemplate;
  }

  /**
   * Call the provider @artist non encoded artist @title non encoded title.
   * 
   * 
   * @param artist 
   * @param title 
   * 
   * @return query return or null if query fails
   */
  public String callProvider(final String artist, final String title) {
    String text = null;
    try {
      URL url = getActualURL(artist, title);
      text = DownloadManager.getTextFromCachedFile(url, getResponseEncoding());
    } catch (final Exception e) {
      Log.warn("Could not retrieve URL {{" + getProviderHostname() + "}}", "{{" + e.getMessage()
          + "}}");
    }
    return text;
  }

  /**
   * Return query URL template like http://..?artist=%artist&songname=%title
   * 
   * @return query URL template like http://..?artist=%artist&songname=%title
   */
  public String getQueryURLTemplate() {
    return queryUrlTemplate;
  }

  /**
   * Return the hostname of the lyrics provider, used as unique identifier for
   * the provider.
   * 
   * @return the provider hostname
   */
  public String getProviderHostname() {
    if (source == null) {
      try {
        source = new URL(queryUrlTemplate).getHost();
      } catch (final MalformedURLException e) {
        Log.warn("Invalid lyrics provider [" + queryUrlTemplate + "]", e.getMessage());
      }
    }
    return source;
  }

  /**
   * Build the actual formated and valorized URL to the provider.
   * 
   * @param artist the artist
   * @param title the title
   * 
   * @return URL the final url
   */
  public URL getActualURL(final String artist, final String title) {
    try {
      String queryString = getQueryURLTemplate();
      queryString = queryString.replace(Const.PATTERN_ARTIST,
          (artist != null) ? NetworkUtils.encodeString(artist) : "");
      queryString = queryString.replace(Const.PATTERN_TRACKNAME,
          (title != null) ? NetworkUtils.encodeString(title) : "");
      return new URL(queryString);
    } catch (MalformedURLException e) {
      Log.error(e);
      return null;
    }
  }

  /**
   * Return the URL from where the lyrics can be displayed from out of Jajuk
   * <br>
   * Note that this URL can be different from the jajuk used url for example if
   * a provider provides a web service interface (jajuk then uses the
   * corresponding URL) and a Web page (this is this URL that is returned from
   * this method).
   * 
   * @param artist 
   * @param title 
   * 
   * @return the Web URL or null if a problem occurred
   */
  public abstract java.net.URL getWebURL(String artist, String title);

  /**
   * Gets the lyrics.
   * 
   * @param artist 
   * @param title 
   * 
   * @return the lyrics
   */
  public abstract String getLyrics(String artist, String title);

  /**
   * {@inheritDoc}
   * @see org.jajuk.services.lyrics.providers.ILyricsProvider#getLyrics()
   */
  @Override
  public String getLyrics() {
    return null;
  }

  /**
   * {@inheritDoc}
   * @see org.jajuk.services.lyrics.providers.ILyricsProvider#setAudioFile(org.jajuk.base.File)
   */
  @Override
  public void setAudioFile(File file) {
    this.audioFile = file;
  }

  /**
   * {@inheritDoc}
   * @see org.jajuk.services.lyrics.providers.ILyricsProvider#getSourceAddress()
   */
  @Override
  public String getSourceAddress() {
    Track track = audioFile.getTrack();
    return getWebURL(track.getArtist().getName2(), track.getName()).toString();
  }
  
  /**
   * Remove HTML entities from the text.
   * @param lyrics the lyrics in HTML text
   * @return text
   */
  String cleanHtml(String lyrics) {
    String ret = lyrics.replaceAll("<br />", "\n");
    ret = ret.replaceAll("<br/>", "\n");
    ret = ret.replaceAll("<br>", "\n");
    ret = ret.replaceAll("’", "'");
    ret = ret.replaceAll("–", "-");
    ret = ret.replaceAll("\u0092", "'");
    ret = ret.replaceAll("\u009c", "oe");
    ret = ret.replaceAll("<p>", "\n");
    ret = ret.replaceAll("<i>", "");
    ret = ret.replaceAll("</i>", "");
    ret = ret.replaceAll("<b>", "");
    ret = ret.replaceAll("</b>", "");
    ret = ret.replaceAll("\t", "");
    ret = ret.replaceAll(""", "'");
    ret = ret.replaceAll("'", "'");
    ret = ret.replaceAll("’", "'");
    ret = ret.replaceAll("…", "…");
    return ret;
  }
}