package com.tesora.dve.db.mysql;

/*
 * #%L
 * Tesora Inc.
 * Database Virtualization Engine
 * %%
 * Copyright (C) 2011 - 2014 Tesora Inc.
 * %%
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License, version 3,
 * as published by the Free Software Foundation.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Affero General Public License for more details.
 * 
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 * #L%
 */

import com.tesora.dve.db.mysql.libmy.*;
import com.tesora.dve.resultset.ColumnMetadata;
import org.apache.log4j.Logger;

import com.tesora.dve.exceptions.PESQLStateException;
import com.tesora.dve.exceptions.PEException;
import com.tesora.dve.resultset.ColumnSet;

import java.util.ArrayList;
import java.util.List;

public class MysqlPrepareStatementCollector extends MysqlPrepareParallelConsumer {

	private static final Logger logger = Logger.getLogger(MysqlPrepareStatementCollector.class);

    List<MyFieldPktResponse> savedParamDefs = new ArrayList<>();
    long stmtID;
	ColumnSet paramColumns;
	ColumnSet resultColumns;
	
	@Override
	void consumeHeader(MyPrepareOKResponse prepareOK) {
        this.stmtID = prepareOK.getStmtId();
		paramColumns = null;//defer building this until it is asked for.
		pstmt.setNumParams(getNumParams());
		resultColumns = new ColumnSet();
		pstmt.setNumColumns(getNumCols());
	}

    public long getStmtID(){
        return stmtID;
    }

	@Override
	void consumeParamDef(MyFieldPktResponse columnDef) throws PEException {
        //defer building metadata object for parameters until someone asks for it via getParamColumns().
        savedParamDefs.add(columnDef);
		pstmt.addParameter(new MyParameter(columnDef.getColumn_type()));
	}

	@Override
	void consumeParamDefEOF(MyEOFPktResponse myEof) {
	}

	@Override
	void consumeColDef(MyFieldPktResponse columnDef) {
		resultColumns.addColumn(FieldMetadataAdapter.buildMetadata(columnDef));
		if (logger.isDebugEnabled())
			logger.debug(this.getClass().getSimpleName() + " reads column " + columnDef);
	}

	@Override
	void consumeColDefEOF(MyEOFPktResponse colEof) {
	}

	@Override
	void consumeError(MyErrorResponse error) throws PESQLStateException {
		throw (PESQLStateException)error.asException();
	}

	public ColumnSet getResultColumns() {
		return resultColumns;
	}
	
	public ColumnSet getParamColumns() {
        if (paramColumns == null){
            paramColumns = new ColumnSet();
            for (MyFieldPktResponse paramDef : savedParamDefs){
                ColumnMetadata meta = FieldMetadataAdapter.buildMetadata(paramDef);
                paramColumns.addColumn(meta);
            }
        }
		return paramColumns;
	}

}