/*
    * 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.doxia.sink.impl;
  
  import javax.swing.text.MutableAttributeSet;
  import javax.swing.text.html.HTML.Tag;
  
  import java.util.Objects;
  
  import org.apache.maven.doxia.markup.XmlMarkup;
  
  /**
   * An abstract <code>Sink</code> for xml markup syntax.
   *
   * @author <a href="mailto:vincent.siveton@gmail.com">Vincent Siveton</a>
   * @since 1.0
   */
  public abstract class AbstractXmlSink extends SinkAdapter implements XmlMarkup {
      /** Default namespace prepended to all tags */
      private String nameSpace;
  
      private boolean firstTag = true;
  
      private boolean insertNewline = true;
  
      /**
       * <p>Setter for the field <code>insertNewline</code>.</p>
       *
       * @param insertNewline a boolean.
       */
      public void setInsertNewline(boolean insertNewline) {
          this.insertNewline = insertNewline;
      }
  
      /**
       * Sets the default namespace that is prepended to all tags written by this sink.
       *
       * @param ns the default namespace.
       * @since 1.1
       */
      public void setNameSpace(String ns) {
          this.nameSpace = ns;
      }
  
      /**
       * Return the default namespace that is prepended to all tags written by this sink.
       *
       * @return the current default namespace.
       * @since 1.1
       */
      public String getNameSpace() {
          return this.nameSpace;
      }
  
      /**
       * Starts a Tag. For instance:
       * <pre>
       * &lt;tag&gt;
       * </pre>
       *
       * @param t a non null tag
       * @see #writeStartTag(javax.swing.text.html.HTML.Tag, javax.swing.text.MutableAttributeSet)
       */
      protected void writeStartTag(Tag t) {
          writeStartTag(t, null);
      }
  
      /**
       * Starts a Tag with attributes. For instance:
       * <pre>
       * &lt;tag attName="attValue"&gt;
       * </pre>
       *
       * @param t a non null tag.
       * @param att a set of attributes. May be null.
       * @see #writeStartTag(javax.swing.text.html.HTML.Tag, javax.swing.text.MutableAttributeSet, boolean)
       */
      protected void writeStartTag(Tag t, MutableAttributeSet att) {
          writeStartTag(t, att, false);
      }
  
      /**
       * Starts a Tag with attributes. For instance:
      * <pre>
      * &lt;tag attName="attValue"&gt;
      * </pre>
      *
      * @param t a non null tag.
      * @param att a set of attributes. May be null.
      * @param isSimpleTag boolean to write as a simple tag.
      */
     protected void writeStartTag(Tag t, MutableAttributeSet att, boolean isSimpleTag) {
         Objects.requireNonNull(t, "t cannot be null");
 
         StringBuilder sb = new StringBuilder();
 
         if (insertNewline && t.isBlock() && !firstTag) {
             sb.append(EOL);
         }
         firstTag = false;
 
         sb.append(LESS_THAN);
 
         if (nameSpace != null) {
             sb.append(nameSpace).append(':');
         }
 
         sb.append(t.toString());
 
         sb.append(SinkUtils.getAttributeString(att));
 
         if (isSimpleTag) {
             sb.append(SPACE).append(SLASH);
         }
 
         sb.append(GREATER_THAN);
 
         write(sb.toString());
     }
 
     /**
      * Writes a system EOL.
      *
      * @since 1.1
      */
     protected void writeEOL() {
         write(EOL);
     }
 
     /**
      * Ends a Tag without writing an EOL. For instance: <pre>&lt;/tag&gt;</pre>.
      *
      * @param t a tag.
      */
     protected void writeEndTag(Tag t) {
         Objects.requireNonNull(t, "t cannot be null");
 
         StringBuilder sb = new StringBuilder();
         sb.append(LESS_THAN);
         sb.append(SLASH);
 
         if (nameSpace != null) {
             sb.append(nameSpace).append(':');
         }
 
         sb.append(t.toString());
         sb.append(GREATER_THAN);
 
         write(sb.toString());
     }
 
     /**
      * Starts a simple Tag. For instance:
      * <pre>
      * &lt;tag /&gt;
      * </pre>
      *
      * @param t a non null tag
      * @see #writeSimpleTag(javax.swing.text.html.HTML.Tag, javax.swing.text.MutableAttributeSet)
      */
     protected void writeSimpleTag(Tag t) {
         writeSimpleTag(t, null);
     }
 
     /**
      * Starts a simple Tag with attributes. For instance:
      * <pre>
      * &lt;tag attName="attValue" /&gt;
      * </pre>
      *
      * @param t a non null tag.
      * @param att a set of attributes. May be null.
      * @see #writeStartTag(javax.swing.text.html.HTML.Tag, javax.swing.text.MutableAttributeSet, boolean)
      */
     protected void writeSimpleTag(Tag t, MutableAttributeSet att) {
         writeStartTag(t, att, true);
     }
 
     /**
      * Write a text to the sink.
      *
      * @param text the given text to write
      */
     protected abstract void write(String text);
 }