/*
    * #%L
    * wcm.io
    * %%
    * Copyright (C) 2014 wcm.io
    * %%
    * Licensed 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.
   * #L%
   */
  package io.wcm.maven.plugins.i18n.readers;
  
  import java.io.File;
  import java.io.IOException;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  
  import javax.xml.XMLConstants;
  
  import org.jdom2.Document;
  import org.jdom2.Element;
  import org.jdom2.JDOMException;
  import org.jdom2.input.SAXBuilder;
  
  /**
   * Reads i18n resources from XML files.
   */
  public class XmlI18nReader implements I18nReader {
  
    @Override
    public Map<String, String> read(File sourceFile) throws IOException {
      try {
        SAXBuilder builder = new SAXBuilder();
        builder.setProperty(XMLConstants.ACCESS_EXTERNAL_DTD, "");
        builder.setProperty(XMLConstants.ACCESS_EXTERNAL_SCHEMA, "");
        Document doc = builder.build(sourceFile);
        Map<String, String> map = new HashMap<>();
        parseXml(doc.getRootElement(), map, "");
        return map;
      }
      catch (JDOMException ex) {
        throw new IOException("Unable to read XML from " + sourceFile.getAbsolutePath(), ex);
      }
    }
  
    private void parseXml(Element node, Map<String, String> map, String prefix) {
      List<Element> children = node.getChildren();
      for (Element child : children) {
        String key = child.getName();
        if (!child.getChildren().isEmpty()) {
          parseXml(child, map, prefix + key + ".");
        }
        else {
          map.put(prefix + key, child.getText());
        }
      }
    }
  
  }