/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you under the Apache 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://www.apache.org/licenses/LICENSE-2.0
   *
   * 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.apache.hadoop.chukwa.inputtools.jplugin;
  
  import java.io.StringReader;
  import java.util.HashMap;
  
  import javax.xml.parsers.DocumentBuilder;
  import javax.xml.parsers.DocumentBuilderFactory;
  import javax.xml.parsers.ParserConfigurationException;
  
  import org.w3c.dom.Attr;
  import org.w3c.dom.Document;
  import org.w3c.dom.Element;
  import org.w3c.dom.NamedNodeMap;
  import org.w3c.dom.NodeList;
  import org.xml.sax.InputSource;
  
  public class GenericChukwaMetricsList extends ChukwaMetricsList<ChukwaMetrics> {
    private static DocumentBuilderFactory factory;
    private static DocumentBuilder docBuilder;
    static {
      factory = DocumentBuilderFactory.newInstance();
      try {
        docBuilder = factory.newDocumentBuilder();
      } catch (ParserConfigurationException e) {
        e.printStackTrace();
      }
    }
    
    public GenericChukwaMetricsList() {
    }
    
    public GenericChukwaMetricsList(String recType) {
      super(recType);
    }
    
    public void fromXml(String xml) throws Exception {
      InputSource is = new InputSource(new StringReader(xml));
      Document doc = docBuilder.parse(is);
      Element root = doc.getDocumentElement();
      setRecordType(root.getTagName());
      long timestamp = Long.parseLong(root.getAttribute("ts"));
      setTimestamp(timestamp);
      
      NodeList children = root.getChildNodes();
      for(int i=0; i<children.getLength(); i++) {
        if(!children.item(i).getNodeName().equals("Metrics")) {
          continue;
        }
        NamedNodeMap attrs = children.item(i).getAttributes();
        if(attrs == null) {
          continue;
        }
        
        GenericChukwaMetrics metrics = new GenericChukwaMetrics();
        for(int a=0; a<attrs.getLength(); a++) {
          Attr attr = (Attr) attrs.item(a);
          String name = attr.getName();
          String value = attr.getValue();
          if(name.equals("key")) {
            metrics.setKey(value);
          } else {
            metrics.put(name, value);
          }
        }
        addMetrics(metrics);
      }
    }
  
    @SuppressWarnings("serial")
    public static class GenericChukwaMetrics extends HashMap<String, String> implements ChukwaMetrics {
      private String key;
      
      @Override
      public HashMap<String, String> getAttributes() {
        return this;
      }
  
      @Override
      public String getKey() {
        return key;
      }
 
     public void setKey(String key) {
       this.key = key;
     }
   }
 }