/**
 *#########################################################################
 *
 * A component of the Gatherer application, part of the Greenstone digital
 * library suite from the New Zealand Digital Library Project at the
 * University of Waikato, New Zealand.
 *
 * <BR><BR>
 *
 * Author: John Thompson, Greenstone Digital Library, University of Waikato
 *
 * <BR><BR>
 *
 * Copyright (C) 1999 New Zealand Digital Library Project
 *
 * <BR><BR>
 *
 * 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
 * (at your option) any later version.
 *
 * <BR><BR>
 *
 * 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.
 *
 * <BR><BR>
 *
 * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 *########################################################################
 */

 




/* GPL_HEADER */
package org.greenstone.gatherer.cdm;
/**************************************************************************************
 * Title:        Gatherer
 * Description:  The Gatherer: a tool for gathering and enriching a digital collection.
 * Copyright:    Copyright (c) 2001
 * Company:      The University of Waikato
 * Written:        /05/02
 * Revised:      22/08/02 Revamped, Optimized and Commented.
 **************************************************************************************/
import org.greenstone.gatherer.cdm.Index;
import org.greenstone.gatherer.cdm.Language;
import org.greenstone.gatherer.util.Utility;
/** This class encapsulates a single collection level metadata assignment, which constitutes a name, language and value.
 * @author John Thompson, Greenstone Digital Library, University of Waikato
 * @version 2.3
 */
public class CollectionMeta
	 implements Comparable {
	 /** A reference to the collection design manager for access to the language manager. */
	 private CollectionDesignManager manager = null;
	 /** The language of this metadata. Should be a two letter code. */
	 private Language language = null;
	 /** The name of the thing this metadata is assigned to, which may index an Index. */
	 private Object name = null;
	 /** The value of this metadata. */
	 private String value = null;
	 /** Constructor.
	  * @param name The object the metadata is assigned to as an <strong>Object</strong>.
	  * @param language The language of the metadata as a <strong>Language</strong>. Should be a two letter code.
	  * @param value The value of this metadata, as a <strong>String</strong>.
	  */
	 public CollectionMeta(CollectionDesignManager manager, Object name, Language language, String value) {
		  this.language = language;
		  this.manager = manager;
		  this.name = name;
		  this.value = value;
	 }
	 /** Method to compare two collection metadata objects to calculate their respective ordering.
	  * @param object The other metadata to compare to, as an <strong>Object</strong>.
	  * @return An <i>int</i> which is less than 0 if this object proceeds the given object, 0 if they are equal and greater than 0 otherwise.
	  * @see org.greenstone.gatherer.cdm.Language
	  */
	 public int compareTo(Object object) {
		  if(object instanceof CollectionMeta) {
				CollectionMeta metadata = (CollectionMeta) object;
				int result = name.toString().compareTo(metadata.getName().toString());
				if(result == 0) {
					 Language other_language = metadata.getLanguage();
					 if(language != null && other_language != null) {
						  result = language.compareTo(metadata.getLanguage());
						  if(result == 0) {
								return value.compareTo(metadata.getValue());
						  }
					 }
					 else if(language != null) {
						  return -1;
					 }
					 else if(other_language != null) {
						  return 1;
					 }
				}
				return result;
		  }
		  return toString().compareTo(object.toString());
	 }
	 /** Method to compare two collection metadata objects for equality.
	  * @param object The other metadata to compare to, as an <strong>Object</strong>.
	  * @return A <i>boolean</i> value of <i>true</i> if the object are equal, <i>false</i> otherwise.
	  */
	 public boolean equals(Object object) {
		  if(compareTo(object) == 0) {
				return true;
		  }
		  return false;
	 }
	 /** Method to retrieve the value of language.
	  * @return The value of language as a <strong>Language</strong>.
	  */
	 public Language getLanguage() {
		  return language;
	 }
	 /** Method to retrieve the value of name.
	  * @return The value of name as an <strong>Object</strong>.
	  */
	 public Object getName() {
		  return name;
	 }
	 /** Method to retrieve the value of value (well great choice of name there).
	  * @return The value of value as a <strong>String</strong>.
	  */
	 public String getValue() {
		  return value;
	 }
	 /** Method to print out this class as it would appear within the collection configuration file.
	  * @return A <strong>String</strong> containing the text value of this class.
	  */
	 public String toString() {
		  String text = "collectionmeta ";
		  if(name instanceof Index) {
				text = text + ".";
				Index index = (Index)name;
				text = text + index.toString(false) + " ";
		  }
		  else {
				text = text + name.toString() + " ";
		  }
		  if(language != null && manager.languages.size() > 0 && !manager.languages.isDefaultLanguage(language)) {
				text = text + "[l=" + language.getCode() + "] ";
		  }
		  text = text + "\"" + Utility.encodeGreenstone(value) + "\"\n";
		  return text;
	 }
	 /** Used to update the contents of this collection level metadata to the given 'new' values.
	  * @param name The new name of the metadata, as a <strong>Object</strong>.
	  * @param language The new <strong>Language</strong> of the metadata.
	  * @param value And the value the metadata is assigned, as a <strong>String</strong>.
	  */
	 public void update(Object name, Language language, String value) {
		  this.name = name;
		  this.language = language;
		  this.value = value;
	 }
	 /** Ensure this is a valid metadata entry by checking that the value is non-null and non-zero length (after having removed whitespace).
	  * @return <i>true</i> if this metadata has a valid value and should be added to the config, <i>false</i> otherwise.
	  */
	 public boolean valid() {
		  return(value != null && value.trim().length() > 0);
	 }
}