/*
 * Copyright (c) 2013, OpenCloudDB/MyCAT and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software;Designed and Developed mainly by many Chinese 
 * opensource volunteers. you can redistribute it and/or modify it under the 
 * terms of the GNU General Public License version 2 only, as published by the
 * Free Software Foundation.
 *
 * This code 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 General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 * 
 * Any questions about this component can be directed to it's project Web address 
 * https://code.google.com/p/opencloudb/.
 *
 */
package org.opencloudb.server.handler;

import java.io.UnsupportedEncodingException;
import java.util.HashMap;
import java.util.Map;

import org.opencloudb.config.ErrorCode;
import org.opencloudb.mysql.ByteUtil;
import org.opencloudb.mysql.PreparedStatement;
import org.opencloudb.net.handler.FrontendPrepareHandler;
import org.opencloudb.net.mysql.ExecutePacket;
import org.opencloudb.server.ServerConnection;
import org.opencloudb.server.response.PreparedStmtResponse;

/**
 * @author mycat
 */
public class ServerPrepareHandler implements FrontendPrepareHandler {

    private ServerConnection source;
    private volatile long pstmtId;
    private Map<String, PreparedStatement> pstmtForSql;
    private Map<Long, PreparedStatement> pstmtForId;

    public ServerPrepareHandler(ServerConnection source) {
        this.source = source;
        this.pstmtId = 0L;
        this.pstmtForSql = new HashMap<String, PreparedStatement>();
        this.pstmtForId = new HashMap<Long, PreparedStatement>();
    }

    @Override
    public void prepare(String sql) {
        PreparedStatement pstmt = null;
        if ((pstmt = pstmtForSql.get(sql)) == null) {
            pstmt = new PreparedStatement(++pstmtId, sql, 0, 0);
            pstmtForSql.put(pstmt.getStatement(), pstmt);
            pstmtForId.put(pstmt.getId(), pstmt);
        }
        PreparedStmtResponse.response(pstmt, source);
    }

    @Override
    public void execute(byte[] data) {
        long pstmtId = ByteUtil.readUB4(data, 5);
        PreparedStatement pstmt = null;
        if ((pstmt = pstmtForSql.get(pstmtId)) == null) {
            source.writeErrMessage(ErrorCode.ER_ERROR_WHEN_EXECUTING_COMMAND, "Unknown pstmtId when executing.");
        } else {
            ExecutePacket packet = new ExecutePacket(pstmt);
            try {
                packet.read(data, source.getCharset());
            } catch (UnsupportedEncodingException e) {
                source.writeErrMessage(ErrorCode.ER_ERROR_WHEN_EXECUTING_COMMAND, e.getMessage());
                return;
            }
            // TODO ...
        }
    }

    @Override
    public void close() {
        // TODO Auto-generated method stub

    }

}