/*
    * Copyright 2004-2024 the original author or authors.
    *
    * 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
    *
    *    https://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 com.ibatis.sqlmap.engine.mapping.statement;
  
  import com.ibatis.sqlmap.client.event.RowHandler;
  import com.ibatis.sqlmap.engine.mapping.result.ResultMap;
  import com.ibatis.sqlmap.engine.scope.StatementScope;
  import com.ibatis.sqlmap.engine.type.XmlTypeMarker;
  
  import java.io.StringWriter;
  import java.sql.ResultSet;
  import java.sql.SQLException;
  
  import javax.xml.XMLConstants;
  import javax.xml.transform.Transformer;
  import javax.xml.transform.TransformerException;
  import javax.xml.transform.TransformerFactory;
  import javax.xml.transform.dom.DOMSource;
  import javax.xml.transform.stream.StreamResult;
  
  import org.w3c.dom.Document;
  
  /**
   * Class to manager row handler access.
   */
  public class RowHandlerCallback {
  
    /** The row handler. */
    private RowHandler rowHandler;
  
    /** The result map. */
    private ResultMap resultMap;
  
    /** The result object. */
    private Object resultObject;
  
    /**
     * Constructor.
     *
     * @param resultMap
     *          - the result map
     * @param resultObject
     *          - the result object
     * @param rowHandler
     *          - the row handler object
     */
    public RowHandlerCallback(ResultMap resultMap, Object resultObject, RowHandler rowHandler) {
      this.rowHandler = rowHandler;
      this.resultMap = resultMap;
      this.resultObject = resultObject;
    }
  
    /**
     * Prepares the row object, and passes it to the row handler.
     *
     * @param statementScope
     *          - the request scope
     * @param results
     *          - the result data
     * @param rs
     *          the rs
     *
     * @throws SQLException
     *           the SQL exception
     */
    public void handleResultObject(StatementScope statementScope, Object[] results, ResultSet rs) throws SQLException {
      Object object;
  
      statementScope.setCurrentNestedKey(null);
      object = resultMap.resolveSubMap(statementScope, rs).setResultObjectValues(statementScope, resultObject, results);
  
      if (object != ResultMap.NO_VALUE) {
        // XML Only special processing. (converts elements to string for easy insertion).
        int stackDepth = statementScope.getSession().getRequestStackDepth();
        if (stackDepth == 1) {
          Class targetType = statementScope.getResultMap().getResultClass();
          if (XmlTypeMarker.class.isAssignableFrom(targetType) && object instanceof Document) {
            object = documentToString((Document) object);
          }
        }
  
        rowHandler.handleRow(object);
      }
    }
  
    /**
    * Document to string.
    *
    * @param document
    *          the document
    *
    * @return the string
    */
   private String documentToString(Document document) {
     String s = null;
 
     try {
       TransformerFactory tFactory = TransformerFactory.newInstance();
       tFactory.setAttribute(XMLConstants.ACCESS_EXTERNAL_DTD, "");
       tFactory.setAttribute(XMLConstants.ACCESS_EXTERNAL_STYLESHEET, "");
       Transformer transformer = tFactory.newTransformer();
 
       DOMSource source = new DOMSource(document);
       StringWriter writer = new StringWriter();
       StreamResult result = new StreamResult(writer);
       transformer.transform(source, result);
       s = writer.getBuffer().toString();
 
     } catch (TransformerException e) {
       throw new RuntimeException("Error occurred.  Cause: " + e, e);
     }
 
     return s;
   }
 
   /**
    * Gets the row handler.
    *
    * @return the row handler
    */
   public RowHandler getRowHandler() {
     return rowHandler;
   }
 
 }