/*
    * 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.util.ArrayList;
  import java.util.Comparator;
  import java.util.Iterator;
  import java.util.List;
  import java.util.SortedSet;
  import java.util.TreeSet;
  
  /**
   * Default implementation of the <code>SegmentType</code>.
   */
  public class SegmentImpl implements Segment, AudioSegment, VideoSegment, AudioVisualSegment {
  
    /** The content type */
    protected Segment.Type type = null;
  
    /** The content element identifier */
    protected String id = null;
  
    /** The content time contraints */
    protected MediaTime mediaTime = null;
  
    /** The text annotations */
    protected List<TextAnnotation> annotations = null;
  
    /** An optional spatio-temporal decomposition */
    protected SpatioTemporalDecomposition spatioTemporalDecomposition = null;
  
    /**
     * Creates a new content segment.
     *
     * @param type
     *          the segment type
     * @param id
     *          the segment identifier
     */
    public SegmentImpl(Segment.Type type, String id) {
      this.type = type;
      this.id = id;
      annotations = new ArrayList<TextAnnotation>();
    }
  
    /**
     * @see org.opencastproject.metadata.mpeg7.Segment#getIdentifier()
     */
    public String getIdentifier() {
      return id;
    }
  
    /**
     * @see org.opencastproject.metadata.mpeg7.Segment#setMediaTime(org.opencastproject.metadata.mpeg7.MediaTime)
     */
    public void setMediaTime(MediaTime mediaTime) {
      this.mediaTime = mediaTime;
    }
  
    /**
     * @see org.opencastproject.metadata.mpeg7.Segment#getMediaTime()
     */
    public MediaTime getMediaTime() {
      return mediaTime;
    }
  
    /**
     * @see org.opencastproject.metadata.mpeg7.Segment#hasTextAnnotations()
     */
    public boolean hasTextAnnotations() {
      return annotations.size() > 0;
    }
  
    /**
     * @see org.opencastproject.metadata.mpeg7.Segment#hasTextAnnotations(java.lang.String)
    */
   public boolean hasTextAnnotations(String language) {
     return hasTextAnnotations(0.0f, 0.0f, language);
   }
 
   /**
    * @see org.opencastproject.metadata.mpeg7.Segment#hasTextAnnotations(float, float)
    */
   public boolean hasTextAnnotations(float relevance, float confidence) {
     return hasTextAnnotations(relevance, confidence, null);
   }
 
   /**
    * @see org.opencastproject.metadata.mpeg7.Segment#hasTextAnnotations(float, float, java.lang.String)
    */
   public boolean hasTextAnnotations(float relevance, float confidence, String language) {
     for (TextAnnotation annotation : annotations) {
       if (annotation.getRelevance() >= relevance && annotation.getConfidence() >= confidence) {
         if (language != null) {
           if (language.equals(annotation.getLanguage())) {
             return true;
           }
         } else {
           return true;
         }
       }
     }
     return false;
   }
 
   /**
    * @see org.opencastproject.metadata.mpeg7.Segment#getTextAnnotationCount()
    */
   public int getTextAnnotationCount() {
     return annotations.size();
   }
 
   /**
    * @see org.opencastproject.metadata.mpeg7.Segment#textAnnotationsByConfidence()
    */
   public Iterator<TextAnnotation> textAnnotationsByConfidence() {
     SortedSet<TextAnnotation> set = new TreeSet<TextAnnotation>(new Comparator<TextAnnotation>() {
       public int compare(TextAnnotation a1, TextAnnotation a2) {
         if (a1.getConfidence() > a2.getConfidence()) {
           return 1;
         } else if (a1.getConfidence() > a2.getConfidence()) {
           return -1;
         }
         return 0;
       }
     });
     set.addAll(annotations);
     return set.iterator();
   }
 
   /**
    * @see org.opencastproject.metadata.mpeg7.Segment#textAnnotationsByRelevance()
    */
   public Iterator<TextAnnotation> textAnnotationsByRelevance() {
     SortedSet<TextAnnotation> set = new TreeSet<TextAnnotation>(new Comparator<TextAnnotation>() {
       public int compare(TextAnnotation a1, TextAnnotation a2) {
         if (a1.getRelevance() > a2.getRelevance()) {
           return 1;
         } else if (a1.getRelevance() > a2.getRelevance()) {
           return -1;
         }
         return 0;
       }
     });
     set.addAll(annotations);
     return set.iterator();
   }
 
   /**
    * @see org.opencastproject.metadata.mpeg7.Segment#createTextAnnotation(float, float, String)
    */
   public TextAnnotation createTextAnnotation(float relevance, float confidence, String language) {
     TextAnnotationImpl annotation = new TextAnnotationImpl(relevance, confidence, language);
     annotations.add(annotation);
     return annotation;
   }
 
   /**
    * @see org.opencastproject.metadata.mpeg7.Segment#textAnnotations()
    */
   public Iterator<TextAnnotation> textAnnotations() {
     return annotations.iterator();
   }
 
   /**
    * {@inheritDoc}
    *
    * @see org.opencastproject.metadata.mpeg7.VideoSegment#createSpatioTemporalDecomposition(boolean, boolean)
    */
   @Override
   public SpatioTemporalDecomposition createSpatioTemporalDecomposition(boolean gap, boolean overlap)
           throws IllegalStateException {
     if (spatioTemporalDecomposition != null) {
       throw new IllegalStateException("A spatio temporal decomposition has already been created");
     }
     spatioTemporalDecomposition = new SpatioTemporalDecompositionImpl(true, false);
     return spatioTemporalDecomposition;
   }
 
   /**
    * {@inheritDoc}
    *
    * @see org.opencastproject.metadata.mpeg7.AudioVisualSegment#getSpatioTemporalDecomposition()
    */
   @Override
   public SpatioTemporalDecomposition getSpatioTemporalDecomposition() {
     return spatioTemporalDecomposition;
   }
 
   /**
    * {@inheritDoc}
    *
    * @see org.opencastproject.metadata.mpeg7.AudioVisualSegment#hasSpatioTemporalDecomposition()
    */
   @Override
   public boolean hasSpatioTemporalDecomposition() {
     return spatioTemporalDecomposition != null;
   }
 
   /**
    * @see java.lang.Object#hashCode()
    */
   @Override
   public int hashCode() {
     return id.hashCode();
   }
 
   /**
    * @see java.lang.Object#equals(java.lang.Object)
    */
   @Override
   public boolean equals(Object obj) {
     if (obj instanceof Segment) {
       return id.equals(((Segment) obj).getIdentifier());
     }
     return super.equals(obj);
   }
 
   /**
    * @see org.opencastproject.mediapackage.XmlElement#toXml(org.w3c.dom.Document)
    */
   public Node toXml(Document document) {
     Element node = document.createElement(type.toString());
     node.setAttribute("id", id);
     node.appendChild(mediaTime.toXml(document));
     if (spatioTemporalDecomposition != null) {
       node.appendChild(spatioTemporalDecomposition.toXml(document));
     }
     for (TextAnnotation annotation : annotations) {
       node.appendChild(annotation.toXml(document));
     }
     return node;
   }
 
 }