/*
    * Licensed to The Apereo Foundation under one or more contributor license
    * agreements. See the NOTICE file distributed with this work for additional
    * information regarding copyright ownership.
    *
    *
    * The Apereo Foundation licenses this file to you under the Educational
    * Community License, Version 2.0 (the "License"); you may not use this file
    * except in compliance with the License. You may obtain a copy of the License
   * at:
   *
   *   http://opensource.org/licenses/ecl2.txt
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
   * License for the specific language governing permissions and limitations under
   * the License.
   *
   */
  
  
  package org.opencastproject.metadata.mpeg7;
  
  import org.w3c.dom.Document;
  import org.w3c.dom.Element;
  import org.w3c.dom.Node;
  
  import java.text.DecimalFormat;
  import java.text.DecimalFormatSymbols;
  import java.util.ArrayList;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Locale;
  
  /**
   * Implementation of text annotations.
   */
  public class TextAnnotationImpl implements TextAnnotation {
  
    /** Number formatter, used to deal with relevance values in a locale independent way */
    private static DecimalFormatSymbols standardSymbols = new DecimalFormatSymbols(Locale.US);
  
    /** Confidence value */
    protected float confidence = -1.0f;
  
    /** Relevance value */
    protected float relevance = -1.0f;
  
    /** Language identifier */
    protected String language = null;
  
    /** Keyword annotations */
    protected List<KeywordAnnotation> keywordAnnotations = null;
  
    /** Free text annotations */
    protected List<FreeTextAnnotation> freeTextAnnotations = null;
  
    static {
      standardSymbols.setDecimalSeparator('.');
    }
  
    /**
     * Creates a new text annotation.
     *
     * @param confidence
     *          the confidence value <code>[0.0..1.0]</code>
     * @param relevance
     *          the relevance value <code>[0.0..1.0]</code>
     * @param language
     *          the language identifier
     */
    public TextAnnotationImpl(float confidence, float relevance, String language) {
      this.confidence = confidence;
      this.relevance = relevance;
      this.language = language;
      keywordAnnotations = new ArrayList<KeywordAnnotation>();
      freeTextAnnotations = new ArrayList<FreeTextAnnotation>();
    }
  
    /**
     * Adds the keyword to this annotation.
     *
     * @param keyword
     *          the keyword
     */
    public void addKeyword(String keyword) {
      addKeywordAnnotation(new KeywordAnnotationImpl(keyword));
    }
  
    /**
     * Adds the keyword to this annotation.
     *
     * @param keyword
     *          the keyword
     * @param type
     *          the keyword type
     */
    public void addKeyword(String keyword, KeywordAnnotation.Type type) {
     addKeywordAnnotation(new KeywordAnnotationImpl(keyword, type));
   }
 
   /**
    * @see org.opencastproject.metadata.mpeg7.TextAnnotation#addKeywordAnnotation(org.opencastproject.metadata.mpeg7.KeywordAnnotation)
    */
   public void addKeywordAnnotation(KeywordAnnotation keywordAnnotation) {
     keywordAnnotations.add(keywordAnnotation);
   }
 
   /**
    * Adds free text to this annotation.
    *
    * @param text
    *          the free text
    */
   public void addFreeText(String text) {
     addFreeTextAnnotation(new FreeTextAnnotationImpl(text));
   }
 
   /**
    * @see org.opencastproject.metadata.mpeg7.TextAnnotation#addFreeTextAnnotation(org.opencastproject.metadata.mpeg7.FreeTextAnnotation)
    */
   public void addFreeTextAnnotation(FreeTextAnnotation freeTextAnnotation) {
     freeTextAnnotations.add(freeTextAnnotation);
   }
 
   /**
    * @see org.opencastproject.metadata.mpeg7.TextAnnotation#getConfidence()
    */
   public float getConfidence() {
     return confidence;
   }
 
   /**
    * @see org.opencastproject.metadata.mpeg7.TextAnnotation#getLanguage()
    */
   public String getLanguage() {
     return language;
   }
 
   /**
    * @see org.opencastproject.metadata.mpeg7.TextAnnotation#getRelevance()
    */
   public float getRelevance() {
     return relevance;
   }
 
   /**
    * @see org.opencastproject.metadata.mpeg7.TextAnnotation#keywordAnnotations()
    */
   public Iterator<KeywordAnnotation> keywordAnnotations() {
     return keywordAnnotations.iterator();
   }
 
   /**
    * @see org.opencastproject.metadata.mpeg7.TextAnnotation#freeTextAnnotations()
    */
   public Iterator<FreeTextAnnotation> freeTextAnnotations() {
     return freeTextAnnotations.iterator();
   }
 
   /**
    * @see org.opencastproject.mediapackage.XmlElement#toXml(org.w3c.dom.Document)
    */
   public Node toXml(Document document) {
     DecimalFormat format = new DecimalFormat("0.0");
     format.setDecimalFormatSymbols(standardSymbols);
     Element node = document.createElement("TextAnnotation");
     if (confidence >= 0.0)
       node.setAttribute("confidence", format.format(confidence));
     if (relevance >= 0.0)
       node.setAttribute("relevance", format.format(relevance));
     if (language != null)
       node.setAttribute("xml:lang", language);
 
     // Keyword anntiations
     if (keywordAnnotations.size() > 0) {
       Element kwAnnotationNode = document.createElement("KeywordAnnotation");
       for (KeywordAnnotation annotation : keywordAnnotations) {
         kwAnnotationNode.appendChild(annotation.toXml(document));
       }
       node.appendChild(kwAnnotationNode);
     }
 
     // Free text anntiations
     for (FreeTextAnnotation annotation : freeTextAnnotations) {
       node.appendChild(annotation.toXml(document));
     }
 
     return node;
   }
 
 }