package nl.dedicon.pipeline.braille.step;
   
   import java.util.HashMap;
   import java.util.Map;
   import java.util.function.UnaryOperator;
   import org.w3c.dom.Document;
   import org.w3c.dom.Element;
   import org.w3c.dom.Node;
   import org.w3c.dom.NodeList;
  
  /**
   * Move notes right after the parent node of their corresponding noteref
   * 
   * @author Paul Rambags
   */
  public class NotesMover {
      
      private static final String NOTE = "note";
      private static final String NOTEREF = "noteref";
      private static final String ID = "id";
      private static final String IDREF = "idref";
      
      private final Map<String, Element> notes = new HashMap<>();      // id -> Element(note)
      private final Map<String, Element> noterefs = new HashMap<>();   // idref -> Element(noteref)
      
      public void collectNotesAndNoterefs(Document document) {
          collect(document, notes, NOTE, ID, s -> s);
          collect(document, noterefs, NOTEREF, IDREF, s -> s.replaceFirst("^#", ""));
      }
  
      private static void collect(Document document, Map map, String nodeName, String attributeName, UnaryOperator<String> attributeFormatter) {
          String namespace = document.getDocumentElement().getNamespaceURI();
          NodeList nodeList = document.getElementsByTagNameNS(namespace, nodeName);
          for (int i = 0; i < nodeList.getLength(); ++i) {
              Element element = (Element)nodeList.item(i);
              String attributeValue = element.getAttribute(attributeName);
              if (attributeValue != null && attributeValue.length() > 0) {
                  map.put(attributeFormatter.apply(attributeValue), element);
              }
          }
      }
      
      public void moveNotes() {
          notes.entrySet().stream().forEach(e -> {
              String id = e.getKey();
              Element note = e.getValue();
  
              Element noteref = noterefs.get(id);
              if (noteref == null) {
                  // note without noteref
                  return;
              }
              Node parent = noteref.getParentNode();
              if (parent == null) {
                  return;
              }
              Node grandParent = parent.getParentNode();
              if (grandParent == null) {
                  return;
              }
              
              grandParent.insertBefore(note, parent.getNextSibling());
          });    
      }
  }