/***
    *     Ambient - A music player for the Android platform
    Copyright (C) 2007 Martin Vysny
    
    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 3 of the License, or
    (at your option) 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, see <http://www.gnu.org/licenses/>.
   */
  package sk.baka.ambient.collection;
  
  import java.io.File;
  import java.io.Serializable;
  
  import sk.baka.ambient.commons.MiscUtils;
  
  /***
   * Contains metadata about a track. Immutable, thread-safe.
   * 
   * @author Martin Vysny
   */
  public final class TrackMetadataBean implements Serializable {
  	/***
  	 * 
  	 */
  	private static final long serialVersionUID = 7772018128569847012L;
  
  	/***
  	 * Database track id.
  	 */
  	private transient final long trackId;
  
  	/***
  	 * The year released.
  	 */
  	private final String yearReleased;
  
  	/***
  	 * Frequency in hz.
  	 */
  	private final int frequency;
  
  	/***
  	 * You can buy the album here
  	 */
  	private final String buyURL;
  
  	/***
  	 * The license URL
  	 */
  	private final String license;
  
  	/***
  	 * A link to artist's page
  	 */
  	private final String artistURL;
  
  	/***
  	 * The artist's description.
  	 */
  	private final String artistDesc;
  
  	/***
  	 * Creates new metadata bean.
  	 * 
  	 * @param trackId
  	 *            the database track id
  	 * @param track
  	 *            the track.
  	 */
  	private TrackMetadataBean(final long trackId, final Builder track) {
  		super();
  		if (track.bitrate < 0)
  			throw new IllegalArgumentException("bitrate must be >=0");
  		if (track.location == null)
  			throw new IllegalArgumentException("location must not be null");
  		if (track.origin == null)
  			throw new IllegalArgumentException("origin must not be null");
  		this.trackId = trackId;
  		this.origin = track.origin;
  		this.title = track.title;
  		this.artist = track.artist;
  		this.composer = track.composer;
  		this.album = track.album;
  		this.genre = track.genre;
  		this.trackNumber = fixTrackNumber(track.trackNumber);
  		this.location = track.location;
  		this.length = track.length;
  		this.bitrate = track.bitrate;
  		this.fileSize = track.fileSize;
  		this.yearReleased = track.yearReleased;
 		this.frequency = track.frequency;
 		this.license = track.license;
 		this.artistURL = track.artistURL;
 		this.buyURL = track.buyURL;
 		this.artistDesc = track.artistDesc;
 	}
 
 	private static String fixTrackNumber(final String tn) {
 		if (tn == null) {
 			return tn;
 		}
 		if (tn.length() == 1 && Character.isDigit(tn.charAt(0))) {
 			return "0" + tn;
 		}
 		return tn;
 	}
 
 	/***
 	 * Returns the name of the track. Returns {@link #getTitle()} unless it's
 	 * <code>null</code> - in this case returns the file name.
 	 * 
 	 * @return the track name, never <code>null</code>.
 	 */
 	public final String getDisplayableName() {
 		if (displayableName == null) {
 			if (MiscUtils.isEmptyOrWhitespace(title)) {
 				if (origin.online) {
 					displayableName = location;
 				} else {
 					displayableName = location.substring(location
 							.lastIndexOf('/') + 1);
 				}
 			} else {
 				displayableName = title;
 			}
 		}
 		return displayableName;
 	}
 
 	private String displayableName;
 
 	/***
 	 * Track title.
 	 */
 	private final String title;
 
 	/***
 	 * Artist.
 	 */
 	private final String artist;
 
 	/***
 	 * Original composer.
 	 */
 	private final String composer;
 
 	/***
 	 * Album name.
 	 */
 	private final String album;
 
 	/***
 	 * Genre.
 	 */
 	private final String genre;
 
 	/***
 	 * Track number.
 	 */
 	private final String trackNumber;
 
 	/***
 	 * Location on the filesystem. May be URL if it is an Internet stream.
 	 */
 	private final String location;
 
 	/***
 	 * Length in seconds. May be 0 if not known.
 	 */
 	private final int length;
 
 	/***
 	 * Bitrate in kbps. If zero then it is not known.
 	 */
 	private final int bitrate;
 
 	/***
 	 * File size in bytes. -1 if the track is an Internet stream.
 	 */
 	private final long fileSize;
 
 	/***
 	 * The track location.
 	 */
 	private final TrackOriginEnum origin;
 
 	/***
 	 * Returns length in the <code>[hh:]mm:ss</code> format.
 	 * 
 	 * @param length
 	 *            the length in seconds
 	 * @return displayable length. If zero then empty string is returned.
 	 */
 	public static String getDisplayableLength(int length) {
 		if (length == 0)
 			return "";
 		final StringBuilder result = new StringBuilder(7);
 		appendDisplayableLength(length, result, true);
 		return result.toString();
 	}
 
 	/***
 	 * Appends length in the <code>[hh:]mm:ss</code> format.
 	 * 
 	 * @param length
 	 *            the length in seconds
 	 * @param builder
 	 *            append the time here.
 	 * @param emptyStringOnZero
 	 *            if <code>true</code> then empty string is returned on zero.
 	 */
 	public static void appendDisplayableLength(final int length,
 			StringBuilder builder, boolean emptyStringOnZero) {
 		int len = length;
 		if ((len == 0) && emptyStringOnZero)
 			return;
 		boolean hours = false;
 		if (len >= 60 * 60) {
 			builder.append(len / (60 * 60));
 			builder.append(':');
 			hours = true;
 		}
 		len %= (60 * 60);
 		final int minutes = len / 60;
 		if ((hours) && (minutes < 10))
 			builder.append('0');
 		builder.append(minutes);
 		builder.append(':');
 		final int seconds = len % 60;
 		if (seconds < 10)
 			builder.append('0');
 		builder.append(seconds);
 	}
 
 	/***
 	 * Returns length in the <code>[hh:]mm:ss</code> format.
 	 * 
 	 * @return displayable length. If zero then empty string is returned.
 	 */
 	public String getDisplayableLength() {
 		return getDisplayableLength(length);
 	}
 
 	/***
 	 * Album name.
 	 * 
 	 * @return the album
 	 */
 	public String getAlbum() {
 		return album;
 	}
 
 	/***
 	 * Artist name.
 	 * 
 	 * @return the artist
 	 */
 	public String getArtist() {
 		return artist;
 	}
 
 	/***
 	 * Bitrate in kbps. If zero then it is not known.
 	 * 
 	 * @return the bitrate
 	 */
 	public int getBitrate() {
 		return bitrate;
 	}
 
 	/***
 	 * Original composer.
 	 * 
 	 * @return the composer
 	 */
 	public String getComposer() {
 		return composer;
 	}
 
 	/***
 	 * File size in bytes. -1 if the track is an Internet stream.
 	 * 
 	 * @return the fileSize
 	 */
 	public long getFileSize() {
 		return fileSize;
 	}
 
 	/***
 	 * The year released.
 	 * 
 	 * @return the yearReleased
 	 */
 	public String getYearReleased() {
 		return yearReleased;
 	}
 
 	/***
 	 * Genre.
 	 * 
 	 * @return the genre
 	 */
 	public String getGenre() {
 		return genre;
 	}
 
 	/***
 	 * Length in seconds. May be 0 if not known.
 	 * 
 	 * @return the length
 	 */
 	public int getLength() {
 		return length;
 	}
 
 	/***
 	 * Location on the filesystem. May be URL if it is an Internet stream.
 	 * 
 	 * @return the location
 	 */
 	public String getLocation() {
 		return location;
 	}
 
 	/***
 	 * Checks if the track denoted by this object is a local one (you can pass
 	 * {@link #getLocation()} to a {@link File} object) , or an Internet stream
 	 * ({@link #getLocation()} is valid URL).
 	 * 
 	 * @return <code>true</code> if the file is local.
 	 */
 	public boolean isLocal() {
 		return !getOrigin().online;
 	}
 
 	/***
 	 * @return the title
 	 */
 	public String getTitle() {
 		return title;
 	}
 
 	/***
 	 * @return the trackNumber
 	 */
 	public String getTrackNumber() {
 		return trackNumber;
 	}
 
 	@Override
 	public boolean equals(Object o) {
 		if (!(o instanceof TrackMetadataBean))
 			return false;
 		return location.equals(((TrackMetadataBean) o).location);
 	}
 
 	@Override
 	public int hashCode() {
 		return location.hashCode();
 	}
 
 	@Override
 	public String toString() {
 		return "Track: " + location;
 	}
 
 	/***
 	 * Frequency in hz.
 	 * 
 	 * @return the frequency in hz, or 0 if not known.
 	 */
 	public int getFrequency() {
 		return frequency;
 	}
 
 	/***
 	 * Database track id.
 	 * 
 	 * @return the trackId
 	 */
 	public long getTrackId() {
 		return trackId;
 	}
 
 	/***
 	 * Creates new bean having equal fields <code>null</code>ed.
 	 * 
 	 * @param other
 	 *            the other bean
 	 * @return bean with equal fields <code>null</code>ed.
 	 */
 	public TrackMetadataBean nullsEqualFields(final TrackMetadataBean other) {
 		return nullsEqualFields(other, false);
 	}
 
 	/***
 	 * Creates new bean having equal fields <code>null</code>ed.
 	 * 
 	 * @param other
 	 *            the other bean
 	 * @param sensibleFieldsOnly
 	 *            if <code>true</code> then only sensible fields are compared -
 	 *            i.e. the {@link #bitrate}, {@link #fileSize},
 	 *            {@link #frequency}, {@link #length}, {@link #title} and
 	 *            {@link #trackNumber} are not nulled even when equal.
 	 * @return bean with equal fields <code>null</code>ed.
 	 */
 	public TrackMetadataBean nullsEqualFields(final TrackMetadataBean other,
 			final boolean sensibleFieldsOnly) {
 		final Builder result = newBuilder();
 		result.album = MiscUtils.nullCompare(this.album, other.album, true) == 0 ? null
 				: this.album;
 		result.artist = MiscUtils.nullCompare(this.artist, other.artist, true) == 0 ? null
 				: this.artist;
 		result.composer = MiscUtils.nullCompare(this.composer, other.composer,
 				true) == 0 ? null : this.composer;
 		result.genre = MiscUtils.nullCompare(this.genre, other.genre, true) == 0 ? null
 				: this.genre;
 		result.yearReleased = MiscUtils.nullCompare(this.yearReleased,
 				other.yearReleased, true) == 0 ? null : this.yearReleased;
 		result.buyURL = MiscUtils.nullCompare(this.buyURL, other.buyURL, true) == 0 ? null
 				: this.buyURL;
 		result.artistURL = MiscUtils.nullCompare(this.artistURL,
 				other.artistURL, true) == 0 ? null : this.artistURL;
 		result.artistDesc = MiscUtils.nullCompare(this.artistDesc,
 				other.artistDesc, true) == 0 ? null : this.artistDesc;
 		result.license = MiscUtils.nullCompare(this.license, other.license,
 				true) == 0 ? null : this.license;
 		result.location = this.location;
 		result.origin = this.origin;
 		if (sensibleFieldsOnly) {
 			result.bitrate = this.bitrate;
 			result.fileSize = this.fileSize;
 			result.frequency = this.frequency;
 			result.length = this.length;
 			result.title = this.title;
 			result.trackNumber = this.trackNumber;
 		} else {
 			result.bitrate = this.bitrate == other.bitrate ? 0 : this.bitrate;
 			result.fileSize = this.fileSize == other.fileSize ? 0
 					: this.fileSize;
 			result.frequency = this.frequency == other.frequency ? 0
 					: this.frequency;
 			result.length = this.length == other.length ? 0 : this.length;
 			result.title = MiscUtils.nullCompare(this.title, other.title, true) == 0 ? null
 					: this.title;
 			result.trackNumber = MiscUtils.nullCompare(this.trackNumber,
 					other.trackNumber, true) == 0 ? null : this.trackNumber;
 		}
 		return result.build(trackId);
 	}
 
 	/***
 	 * An empty bean.
 	 */
 	public final static TrackMetadataBean EMPTY;
 	static {
 		EMPTY = newBuilder().setOrigin(TrackOriginEnum.LocalFs)
 				.setLocation("/").build(-1);
 	}
 
 	/***
 	 * The track origin.
 	 * 
 	 * @return origin, never <code>null</code>.
 	 */
 	public TrackOriginEnum getOrigin() {
 		// deserialization of older format could leave this field null. Handle
 		// this case
 		return origin == null ? TrackOriginEnum.LocalFs : origin;
 	}
 
 	/***
 	 * You can buy the album here
 	 * 
 	 * @return the buyURL
 	 */
 	public String getBuyURL() {
 		return buyURL;
 	}
 
 	/***
 	 * The license URL
 	 * 
 	 * @return the license
 	 */
 	public String getLicense() {
 		return license;
 	}
 
 	/***
 	 * A link to artist's page
 	 * 
 	 * @return the artistURL
 	 */
 	public String getArtistURL() {
 		return artistURL;
 	}
 
 	/***
 	 * The artist's description.
 	 * 
 	 * @return the artistDesc
 	 */
 	public String getArtistDesc() {
 		return artistDesc;
 	}
 
 	/***
 	 * Returns new track metadata builder instance.
 	 * 
 	 * @return the builder instance.
 	 */
 	public static Builder newBuilder() {
 		return new Builder();
 	}
 
 	/***
 	 * The mutable version of {@link TrackMetadataBean}. Use it to gradually
 	 * build the bean. Thread-unsafe.
 	 * 
 	 * @author Martin Vysny
 	 */
 	public final static class Builder {
 		/***
 		 * The year released.
 		 */
 		public String yearReleased;
 
 		/***
 		 * The year released.
 		 * 
 		 * @param yearReleased
 		 *            the yearReleased to set
 		 * @return this
 		 */
 		public Builder setYearReleased(String yearReleased) {
 			this.yearReleased = yearReleased;
 			return this;
 		}
 
 		/***
 		 * Frequency in hz.
 		 * 
 		 * @param frequency
 		 *            the frequency to set
 		 * @return this
 		 */
 		public Builder setFrequency(int frequency) {
 			this.frequency = frequency;
 			return this;
 		}
 
 		/***
 		 * You can buy the album here.
 		 * 
 		 * @param buyURL
 		 *            the buyURL to set
 		 * @return this
 		 */
 		public Builder setBuyURL(String buyURL) {
 			this.buyURL = buyURL;
 			return this;
 		}
 
 		/***
 		 * The license URL
 		 * 
 		 * @param license
 		 *            the license to set
 		 * @return this
 		 */
 		public Builder setLicense(String license) {
 			this.license = license;
 			return this;
 		}
 
 		/***
 		 * A link to artist's page
 		 * 
 		 * @param artistURL
 		 *            the artistURL to set
 		 * @return this
 		 */
 		public Builder setArtistURL(String artistURL) {
 			this.artistURL = artistURL;
 			return this;
 		}
 
 		/***
 		 * The artist's description.
 		 * 
 		 * @param artistDesc
 		 *            the artistDesc to set
 		 * @return this
 		 */
 		public Builder setArtistDesc(String artistDesc) {
 			this.artistDesc = artistDesc;
 			return this;
 		}
 
 		/***
 		 * Track title.
 		 * 
 		 * @param title
 		 *            the title to set
 		 * @return this
 		 */
 		public Builder setTitle(String title) {
 			this.title = title;
 			return this;
 		}
 
 		/***
 		 * @param artist
 		 *            the artist to set
 		 * @return this
 		 */
 		public Builder setArtist(String artist) {
 			this.artist = artist;
 			return this;
 		}
 
 		/***
 		 * Original composer.
 		 * 
 		 * @param composer
 		 *            the composer to set
 		 * @return this
 		 */
 		public Builder setComposer(String composer) {
 			this.composer = composer;
 			return this;
 		}
 
 		/***
 		 * Album name.
 		 * 
 		 * @param album
 		 *            the album to set
 		 * @return this
 		 */
 		public Builder setAlbum(String album) {
 			this.album = album;
 			return this;
 		}
 
 		/***
 		 * Genre.
 		 * 
 		 * @param genre
 		 *            the genre to set
 		 * @return this
 		 */
 		public Builder setGenre(String genre) {
 			this.genre = genre;
 			return this;
 		}
 
 		/***
 		 * Track number in the album ordering.
 		 * 
 		 * @param trackNumber
 		 *            the trackNumber to set
 		 * @return this
 		 */
 		public Builder setTrackNumber(String trackNumber) {
 			this.trackNumber = trackNumber;
 			return this;
 		}
 
 		/***
 		 * Location on the filesystem. May be URL if it is an Internet stream.
 		 * 
 		 * @param location
 		 *            the location to set
 		 * @return this
 		 */
 		public Builder setLocation(String location) {
 			this.location = location;
 			return this;
 		}
 
 		/***
 		 * Length in seconds. May be 0 if not known.
 		 * 
 		 * @param length
 		 *            the length to set
 		 * @return this
 		 */
 		public Builder setLength(int length) {
 			this.length = length;
 			return this;
 		}
 
 		/***
 		 * Bitrate in kbps. If zero then it is not known.
 		 * 
 		 * @param bitrate
 		 *            the bitrate to set
 		 * @return this
 		 */
 		public Builder setBitrate(int bitrate) {
 			this.bitrate = bitrate;
 			return this;
 		}
 
 		/***
 		 * File size in bytes. -1 if the track is an Internet stream.
 		 * 
 		 * @param fileSize
 		 *            the fileSize to set
 		 * @return this
 		 */
 		public Builder setFileSize(long fileSize) {
 			this.fileSize = fileSize;
 			return this;
 		}
 
 		/***
 		 * The track location.
 		 * 
 		 * @param origin
 		 *            the origin to set
 		 * @return this
 		 */
 		public Builder setOrigin(TrackOriginEnum origin) {
 			this.origin = origin;
 			return this;
 		}
 
 		/***
 		 * Frequency in hz.
 		 */
 		public int frequency;
 
 		/***
 		 * You can buy the album here
 		 */
 		public String buyURL;
 
 		/***
 		 * The license URL
 		 */
 		public String license;
 
 		/***
 		 * A link to artist's page
 		 */
 		public String artistURL;
 
 		/***
 		 * The artist's description.
 		 */
 		public String artistDesc;
 
 		/***
 		 * Track title.
 		 */
 		public String title;
 
 		/***
 		 * Artist.
 		 */
 		public String artist;
 
 		/***
 		 * Original composer.
 		 */
 		public String composer;
 
 		/***
 		 * Album name.
 		 */
 		public String album;
 
 		/***
 		 * Genre.
 		 */
 		public String genre;
 
 		/***
 		 * Track number.
 		 */
 		public String trackNumber;
 
 		/***
 		 * Location on the filesystem. May be URL if it is an Internet stream.
 		 */
 		public String location;
 
 		/***
 		 * Length in seconds. May be 0 if not known.
 		 */
 		public int length;
 
 		/***
 		 * Bitrate in kbps. If zero then it is not known.
 		 */
 		public int bitrate;
 
 		/***
 		 * File size in bytes. -1 if the track is an Internet stream.
 		 */
 		public long fileSize;
 
 		/***
 		 * The track location.
 		 */
 		public TrackOriginEnum origin;
 
 		/***
 		 * Creates new metadata bean.
 		 * 
 		 * @param trackId
 		 *            the database track id
 		 * @return new bean instance
 		 */
 		public TrackMetadataBean build(final long trackId) {
 			return new TrackMetadataBean(trackId, this);
 		}
 
 		/***
 		 * Polls data from given track.
 		 * 
 		 * @param track
 		 *            copy data from given track.
 		 * @return this
 		 */
 		public Builder getData(final TrackMetadataBean track) {
 			album = track.album;
 			artist = track.artist;
 			artistDesc = track.artistDesc;
 			artistURL = track.artistURL;
 			bitrate = track.bitrate;
 			buyURL = track.buyURL;
 			composer = track.composer;
 			fileSize = track.fileSize;
 			frequency = track.frequency;
 			genre = track.genre;
 			length = track.length;
 			license = track.license;
 			location = track.location;
 			origin = track.origin;
 			title = track.title;
 			trackNumber = track.trackNumber;
 			yearReleased = track.yearReleased;
 			return this;
 		}
 	}
 }