content: // This file is part of AceWiki.
  // Copyright 2008-2013, AceWiki developers.
  // 
  // AceWiki is free software: you can redistribute it and/or modify it under the terms of the GNU
  // Lesser General Public License as published by the Free Software Foundation, either version 3 of
  // the License, or (at your option) any later version.
  // 
  // AceWiki 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
  // Lesser General Public License for more details.
  // 
  // You should have received a copy of the GNU Lesser General Public License along with AceWiki. If
  // not, see http://www.gnu.org/licenses/.
  
  package ch.uzh.ifi.attempto.acewiki.core;
  
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Map;
  import java.util.TreeMap;
  
  /**
   * This class is the default implementation of a word index.
   * 
   * @author Tobias Kuhn
   */
  //TODO Different ontology elements should be allowed to have overlapping word forms.
  public class DefaultWordIndex implements WordIndex {
  	
  	private Map<String, OntologyElement> wordIndex = new TreeMap<String, OntologyElement>();
  	private List<OntologyElement> elements = new ArrayList<OntologyElement>();
  	
  	public void elementAdded(OntologyElement element) {
  		if (elements.contains(element)) {
  			throw new RuntimeException("Registration failed: Already registered.");
  		}
  		elements.add(element);
  		for (String word : element.getWords()) {
  			if (word == null) continue;
  			
  			if (getElement(word) == null) {
  				wordIndex.put(word, element);
  			} else if (getElement(word) != element) {
  				throw new RuntimeException(
  						"Registration failed: The word '" + word + "' is already used."
  					);
  			}
  		}
  	}
  	
  	public void elementRemoved(OntologyElement element) {
  		elements.remove(element);
  		for (String word : element.getWords()) {
  			if (word == null) continue;
  			wordIndex.remove(word);
  		}
  	}
  	
  	public void elementBeforeChange(OntologyElement element) {
  		for (String word : element.getWords()) {
  			if (word != null) {
  				wordIndex.remove(word);
  			}
  		}
  	}
  	
  	public void elementAfterChange(OntologyElement element) {
  		for (String word : element.getWords()) {
  			if (word != null) {
  				if (getElement(word) == null) {
  					wordIndex.put(word, element);
  				} else if (getElement(word) != element) {
  					throw new RuntimeException(
  							"Word update failed: The word '" + word + "' is already used."
  						);
  				}
  			}
  		}
  	}
  	
  	public OntologyElement getElement(String word) {
  		return wordIndex.get(word);
  	}
  
  	public List<OntologyElement> searchForElements(String searchText) {
  		List<OntologyElement> searchResult = new ArrayList<OntologyElement>();
  		String s = searchText.toLowerCase().replace('_', ' ');
  		for (OntologyElement e : elements) {
  			for (String w : e.getWords()) {
  				if (w == null) continue;
  				if (w.toLowerCase().replace('_', ' ').contains(s)) {
  					searchResult.add(e);
  					break;
  				}
  			}
  		}
  		LanguageUtils.sortOntologyElements(searchResult);
  		return searchResult;
  	}
  
  }
  