/*
    * 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.maven.shared.utils.xml;
  
  import javax.annotation.Nonnull;
  
  import java.io.IOException;
  import java.io.StringWriter;
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Map;
  
  /**
   * A reimplementation of Plexus Xpp3Dom based on the public interface of Plexus Xpp3Dom.
   *
   * @author Kristian Rosenvold
   */
  public class Xpp3Dom implements Iterable<Xpp3Dom> {
      private static final long serialVersionUID = 2567894443061173996L;
  
      private String name; // plexus: protected
  
      private String value; // plexus: protected
  
      private Map<String, String> attributes; // plexus: protected
  
      final List<Xpp3Dom> childList; // plexus: protected
  
      final Map<String, Xpp3Dom> childMap; // plexus: protected
  
      private Xpp3Dom parent; // plexus: protected
  
      /**
       * The attribute which identifies merge/append.
       */
      public static final String CHILDREN_COMBINATION_MODE_ATTRIBUTE = "combine.children";
  
      private static final String CHILDREN_COMBINATION_MERGE = "merge";
  
      /**
       * The attribute append.
       */
      public static final String CHILDREN_COMBINATION_APPEND = "append";
  
      @SuppressWarnings("UnusedDeclaration")
      private static final String DEFAULT_CHILDREN_COMBINATION_MODE = CHILDREN_COMBINATION_MERGE; // plexus: public
  
      /**
       * The name of the attribute.
       */
      public static final String SELF_COMBINATION_MODE_ATTRIBUTE = "combine.self";
  
      /**
       * The attributes which identifies <code>override</code>.
       */
      public static final String SELF_COMBINATION_OVERRIDE = "override"; // plexus: public
  
      /**
       * The attribute which identifies <code>merge</code>
       */
      public static final String SELF_COMBINATION_MERGE = "merge";
  
      @SuppressWarnings("UnusedDeclaration")
      private static final String DEFAULT_SELF_COMBINATION_MODE = SELF_COMBINATION_MERGE; // plexus: public
  
      private static final String[] EMPTY_STRING_ARRAY = new String[0];
      private static final Xpp3Dom[] EMPTY_DOM_ARRAY = new Xpp3Dom[0];
  
      /**
       * @param name The name of the instance.
       */
      public Xpp3Dom(String name) {
          this.name = name;
          childList = new ArrayList<Xpp3Dom>();
          childMap = new HashMap<String, Xpp3Dom>();
      }
  
      /**
       * Create instance.
       * @param source The source.
      */
     public Xpp3Dom(Xpp3Dom source) {
         this(source, source.getName());
     }
 
     /**
      * Create instance.
      * @param src The source Dom.
      * @param name The name of the Dom.
      */
     public Xpp3Dom(@Nonnull Xpp3Dom src, String name) {
         this.name = name;
 
         int size = src.getChildCount();
         childList = new ArrayList<Xpp3Dom>(size);
         childMap = new HashMap<String, Xpp3Dom>();
 
         setValue(src.getValue());
 
         for (String attributeName : src.getAttributeNames()) {
             setAttribute(attributeName, src.getAttribute(attributeName));
         }
 
         for (Xpp3Dom xpp3Dom : src.getChildren()) {
             addChild(new Xpp3Dom(xpp3Dom));
         }
     }
 
     /**
      * @return The current name.
      */
     public String getName() {
         return name;
     }
 
     /**
      * @return The current value.
      */
     @Nonnull
     public String getValue() {
         return value;
     }
 
     /**
      * @param value The value to be set.
      */
     public void setValue(@Nonnull String value) {
         this.value = value;
     }
 
     /**
      * @return The array of attribute names.
      */
     public String[] getAttributeNames() {
         boolean isNothing = attributes == null || attributes.isEmpty();
         return isNothing ? EMPTY_STRING_ARRAY : attributes.keySet().toArray(new String[attributes.size()]);
     }
 
     /**
      * @param nameParameter The name of the attribute.
      * @return The attribute value.
      */
     public String getAttribute(String nameParameter) {
         return this.attributes != null ? this.attributes.get(nameParameter) : null;
     }
 
     /**
      * @param nameParameter The name of the attribute.
      * @param valueParameter The value of the attribute.
      */
     public void setAttribute(@Nonnull String nameParameter, @Nonnull String valueParameter) {
         if (valueParameter == null) {
             throw new NullPointerException("value can not be null");
         }
         if (nameParameter == null) {
             throw new NullPointerException("name can not be null");
         }
         if (attributes == null) {
             attributes = new HashMap<String, String>();
         }
 
         attributes.put(nameParameter, valueParameter);
     }
 
     /**
      * @param i The index to be selected.
      * @return The child selected by index.
      */
     public Xpp3Dom getChild(int i) {
         return childList.get(i);
     }
 
     /**
      * @param nameParameter The name of the child.
      * @return The child selected by name.
      */
     public Xpp3Dom getChild(String nameParameter) {
         return childMap.get(nameParameter);
     }
 
     /**
      * @param child The child to be added.
      */
     public void addChild(Xpp3Dom child) {
         child.setParent(this);
         childList.add(child);
         childMap.put(child.getName(), child);
     }
 
     /**
      * @return The array of childs.
      */
     public Xpp3Dom[] getChildren() {
         boolean isNothing = childList == null || childList.isEmpty();
         return isNothing ? EMPTY_DOM_ARRAY : childList.toArray(new Xpp3Dom[childList.size()]);
     }
 
     private List<Xpp3Dom> getChildrenList() {
         boolean isNothing = childList == null || childList.isEmpty();
         return isNothing ? Collections.<Xpp3Dom>emptyList() : childList;
     }
 
     /**
      * @param nameParameter The name of the child.
      * @return The array of the Dom.
      */
     public Xpp3Dom[] getChildren(String nameParameter) {
         List<Xpp3Dom> children = getChildrenList(nameParameter);
         return children.toArray(new Xpp3Dom[children.size()]);
     }
 
     List<Xpp3Dom> getChildrenList(String nameParameter) {
         if (childList == null) {
             return Collections.emptyList();
         } else {
             ArrayList<Xpp3Dom> children = new ArrayList<Xpp3Dom>();
             for (Xpp3Dom aChildList : childList) {
                 if (nameParameter.equals(aChildList.getName())) {
                     children.add(aChildList);
                 }
             }
             return children;
         }
     }
 
     /**
      * @return The number of childs.
      */
     public int getChildCount() {
         if (childList == null) {
             return 0;
         }
 
         return childList.size();
     }
 
     /**
      * @param i The child to be removed.
      */
     public void removeChild(int i) {
         Xpp3Dom child = childList.remove(i);
         childMap.values().remove(child);
         child.setParent(null);
     }
 
     /**
      * @return The current parent.
      */
     public Xpp3Dom getParent() {
         return parent;
     }
 
     /**
      * @param parent Set the parent.
      */
     public void setParent(Xpp3Dom parent) {
         this.parent = parent;
     }
 
     /**
      * @param dominant The dominant part.
      * @param recessive The recessive part.
      * @param childMergeOverride true if child merge will take precedence false otherwise.
      * @return The merged Xpp3Dom.
      */
     public static Xpp3Dom mergeXpp3Dom(Xpp3Dom dominant, Xpp3Dom recessive, Boolean childMergeOverride) {
         return Xpp3DomUtils.mergeXpp3Dom(dominant, recessive, childMergeOverride);
     }
 
     /**
      * @param dominant The dominant part.
      * @param recessive The recessive part.
      * @return The merged Xpp3Dom.
      */
     public static Xpp3Dom mergeXpp3Dom(Xpp3Dom dominant, Xpp3Dom recessive) {
         return Xpp3DomUtils.mergeXpp3Dom(dominant, recessive);
     }
 
     /** {@inheritDoc} */
     public boolean equals(Object obj) {
         if (obj == this) {
             return true;
         }
 
         if (!(obj instanceof Xpp3Dom)) {
             return false;
         }
 
         Xpp3Dom dom = (Xpp3Dom) obj;
 
         return !(name == null ? dom.name != null : !name.equals(dom.name))
                 && !(value == null ? dom.value != null : !value.equals(dom.value))
                 && !(attributes == null ? dom.attributes != null : !attributes.equals(dom.attributes))
                 && !(childList == null ? dom.childList != null : !childList.equals(dom.childList));
     }
 
     /** {@inheritDoc} */
     public int hashCode() {
         int result = 17;
         result = 37 * result + (name != null ? name.hashCode() : 0);
         result = 37 * result + (value != null ? value.hashCode() : 0);
         result = 37 * result + (attributes != null ? attributes.hashCode() : 0);
         result = 37 * result + (childList != null ? childList.hashCode() : 0);
         return result;
     }
 
     /** {@inheritDoc} */
     public String toString() {
         try {
             StringWriter writer = new StringWriter();
             Xpp3DomWriter.write(getPrettyPrintXMLWriter(writer), this);
             return writer.toString();
         } catch (final IOException e) {
             // JDK error in StringWriter.
             throw (AssertionError) new AssertionError("Unexpected IOException from StringWriter.").initCause(e);
         }
     }
 
     /**
      * @return Unescaped string.
      */
     public String toUnescapedString() {
         try {
             StringWriter writer = new StringWriter();
             Xpp3DomWriter.write(getPrettyPrintXMLWriter(writer), this, false);
             return writer.toString();
         } catch (final IOException e) {
             // JDK error in StringWriter.
             throw (AssertionError) new AssertionError("Unexpected IOException from StringWriter.").initCause(e);
         }
     }
 
     private PrettyPrintXMLWriter getPrettyPrintXMLWriter(StringWriter writer) {
         return new PrettyPrintXMLWriter(writer, "UTF-8", null);
     }
 
     /**
      * Warning: this is not the reverse of {@link #isEmpty}.
      * Whitespace only strings are both empty and not empty.
      *
      * @param str the string to be checked
      * @return true if the string is not empty (length &gt; 0) and not <code>null</code>
      * @deprecated use <code>str != null &amp;&amp; !str.isEmpty()</code>
      */
     @Deprecated
     public static boolean isNotEmpty(String str) {
         return str != null && str.length() > 0;
     }
 
     /**
      * Warning: this is not the reverse of {@link #isNotEmpty}.
      * Whitespace only strings are both empty and not empty.
      *
      * @param str the string to be checked
      * @return true if the string only contains whitespace or is <code>null</code>
      * @deprecated use <code>str == null || str.trim().isEmpty()</code>
      */
     @Deprecated
     public static boolean isEmpty(String str) {
         return str == null || str.trim().length() == 0;
     }
 
     /** {@inheritDoc} */
     public Iterator<Xpp3Dom> iterator() {
         return getChildrenList().iterator();
     }
 }