/*

   Derby - Class org.apache.derby.impl.sql.execute.rts.RealUnionResultSetStatistics

   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.derby.impl.sql.execute.rts;

import org.apache.derby.iapi.sql.execute.ResultSetStatistics;
import org.apache.derby.iapi.services.io.StoredFormatIds;

import org.apache.derby.iapi.services.i18n.MessageService;
import org.apache.derby.iapi.reference.SQLState;

import org.apache.derby.iapi.services.io.FormatableHashtable;

import java.io.ObjectOutput;
import java.io.ObjectInput;
import java.io.IOException;
import org.apache.derby.catalog.UUID;
import org.apache.derby.impl.sql.catalog.XPLAINResultSetDescriptor;
import org.apache.derby.impl.sql.catalog.XPLAINResultSetTimingsDescriptor;
import org.apache.derby.impl.sql.execute.xplain.XPLAINUtil;
import org.apache.derby.iapi.sql.execute.xplain.XPLAINVisitor;

/**
  ResultSetStatistics implemenation for UnionResultSet.


*/
public class RealUnionResultSetStatistics 
	extends RealNoPutResultSetStatistics
{

	/* Leave these fields public for object inspectors */
	public int rowsSeenLeft;
	public int rowsSeenRight;
	public int rowsReturned;
	public ResultSetStatistics leftResultSetStatistics;
	public ResultSetStatistics rightResultSetStatistics;

	// CONSTRUCTORS

	/**
	 * 
	 *
	 */
    public	RealUnionResultSetStatistics(
								int numOpens,
								int rowsSeen,
								int rowsFiltered,
								long constructorTime,
								long openTime,
								long nextTime,
								long closeTime,
								int resultSetNumber,
								int rowsSeenLeft,
								int rowsSeenRight,
								int rowsReturned,
								double optimizerEstimatedRowCount,
								double optimizerEstimatedCost,
								ResultSetStatistics leftResultSetStatistics,
								ResultSetStatistics rightResultSetStatistics
								)
	{
		super(
			numOpens,
			rowsSeen,
			rowsFiltered,
			constructorTime,
			openTime,
			nextTime,
			closeTime,
			resultSetNumber,
			optimizerEstimatedRowCount,
			optimizerEstimatedCost
			);
		this.rowsSeenLeft = rowsSeenLeft;
		this.rowsSeenRight = rowsSeenRight;
		this.rowsReturned = rowsReturned;
		this.leftResultSetStatistics = leftResultSetStatistics;
		this.rightResultSetStatistics = rightResultSetStatistics;
	}

	// ResultSetStatistics methods

	/**
	 * Return the statement execution plan as a String.
	 *
	 * @param depth	Indentation level.
	 *
	 * @return String	The statement execution plan as a String.
	 */
	public String getStatementExecutionPlanText(int depth)
	{
		initFormatInfo(depth);

		return
			indent + MessageService.getTextMessage(SQLState.RTS_UNION_RS) +
				":\n" +
			indent + MessageService.getTextMessage(SQLState.RTS_NUM_OPENS) +
				" = " + numOpens + "\n" +
			indent + MessageService.getTextMessage(
												SQLState.RTS_ROWS_SEEN_LEFT) +
				" = " + rowsSeenLeft + "\n" +
			indent + MessageService.getTextMessage(
												SQLState.RTS_ROWS_SEEN_RIGHT) +
				" = " + rowsSeenRight + "\n" +
			indent + MessageService.getTextMessage(
												SQLState.RTS_ROWS_RETURNED) +
				" = " + rowsReturned + "\n" +
			dumpTimeStats(indent, subIndent) + "\n" +
			dumpEstimatedCosts(subIndent) + "\n" +
			indent + MessageService.getTextMessage(SQLState.RTS_LEFT_RS) +
				":\n" +
			leftResultSetStatistics.getStatementExecutionPlanText(sourceDepth) +
				"\n" +
			indent + MessageService.getTextMessage(SQLState.RTS_RIGHT_RS) +
				":\n" +
			rightResultSetStatistics.getStatementExecutionPlanText(
																sourceDepth) +
				"\n";
	}

	/**
	 * Return information on the scan nodes from the statement execution 
	 * plan as a String.
	 *
	 * @param depth	Indentation level.
	 * @param tableName if not NULL then print information for this table only
	 *
	 * @return String	The information on the scan nodes from the 
	 *					statement execution plan as a String.
	 */
	public String getScanStatisticsText(String tableName, int depth)
	{
		return leftResultSetStatistics.getScanStatisticsText(tableName, depth)
			+ rightResultSetStatistics.getScanStatisticsText(tableName, depth);
	}


	// Class implementation
	
	public String toString()
	{
		return getStatementExecutionPlanText(0);
	}
  public java.util.Vector<ResultSetStatistics> getChildren(){
    java.util.Vector<ResultSetStatistics> children = new java.util.Vector<ResultSetStatistics>();
    children.addElement(leftResultSetStatistics);
    children.addElement(rightResultSetStatistics);
    return children;
  }
	/**
   * Format for display, a name for this node. Since this is a SQL operator name,
   * it does not need to be internationalized.
	 *
	 */
  public String getNodeName(){
      return "Union";
  }
  
  // -----------------------------------------------------
  // XPLAINable Implementation
  // -----------------------------------------------------
  
    public void accept(XPLAINVisitor visitor) {
        int noChildren = 0;
        if(this.leftResultSetStatistics!=null) noChildren++;
        if(this.rightResultSetStatistics!=null) noChildren++;
        
        //inform the visitor
        visitor.setNumberOfChildren(noChildren);
        
        // pre-order, depth-first traversal
        // me first
        visitor.visit(this);
        // then visit first my left child
        if(leftResultSetStatistics!=null){
            leftResultSetStatistics.accept(visitor);
        }
        // and then my right child
        if(rightResultSetStatistics!=null){
            rightResultSetStatistics.accept(visitor);
        }
    }  
    public String getRSXplainType() { return XPLAINUtil.OP_UNION; }
    public String getRSXplainDetails()
    {
        return "("+this.resultSetNumber + ")";
    }
    public Object getResultSetDescriptor(Object rsID, Object parentID,
            Object scanID, Object sortID, Object stmtID, Object timingID)
    {
        return new XPLAINResultSetDescriptor(
           (UUID)rsID,
           getRSXplainType(),
           getRSXplainDetails(),
           this.numOpens,
           null,                           // index updates
           null,                           // lock mode
           null,                           // lock granularity
           (UUID)parentID,
           this.optimizerEstimatedRowCount,
           this.optimizerEstimatedCost,
           null,                              // affected rows
           null,                              // deferred rows
           null,                              // the input rows
           this.rowsSeenLeft,
           this.rowsSeenRight,
           this.rowsFiltered,
           this.rowsReturned,
           null,                           // the empty right rows
           null,                           // index key optimization
           (UUID)scanID,
           (UUID)sortID,
           (UUID)stmtID,
           (UUID)timingID);
    }
}
