/*
 * Copyright (C) 2016-2022 ActionTech.
 * License: http://www.gnu.org/licenses/gpl.html GPL version 2 or higher.
 */

package com.actiontech.dble.services.manager.response;

import com.actiontech.dble.backend.mysql.PacketUtil;
import com.actiontech.dble.config.Fields;
import com.actiontech.dble.net.mysql.*;
import com.actiontech.dble.services.manager.ManagerService;
import com.actiontech.dble.singleton.TsQueriesCounter;
import com.actiontech.dble.util.LongUtil;

import java.nio.ByteBuffer;

/**
 * Created by szf on 2019/12/17.
 */
public final class ShowQuestions {

    private ShowQuestions() {
    }

    private static final int FIELD_COUNT = 2;
    private static final ResultSetHeaderPacket HEADER = PacketUtil.getHeader(FIELD_COUNT);
    private static final FieldPacket[] FIELDS = new FieldPacket[FIELD_COUNT];
    private static final EOFPacket EOF = new EOFPacket();

    static {
        int i = 0;
        byte packetId = 0;
        HEADER.setPacketId(++packetId);

        FIELDS[i] = PacketUtil.getField("Questions", Fields.FIELD_TYPE_LONG);
        FIELDS[i++].setPacketId(++packetId);

        FIELDS[i] = PacketUtil.getField("Transactions", Fields.FIELD_TYPE_LONG);
        FIELDS[i++].setPacketId(++packetId);

        EOF.setPacketId(++packetId);
    }

    public static void execute(ManagerService service) {
        ByteBuffer buffer = service.allocate();

        // write header
        buffer = HEADER.write(buffer, service, true);

        // write fields
        for (FieldPacket field : FIELDS) {
            buffer = field.write(buffer, service, true);
        }

        // write eof
        buffer = EOF.write(buffer, service, true);

        // write rows
        byte packetId = EOF.getPacketId();


        TsQueriesCounter.CalculateResult result = TsQueriesCounter.getInstance().calculate();
        RowDataPacket row = new RowDataPacket(FIELD_COUNT);
        row.add(LongUtil.toBytes(result.queries));
        row.add(LongUtil.toBytes(result.transactions));
        row.setPacketId(++packetId);
        buffer = row.write(buffer, service, true);

        EOFRowPacket lastEof = new EOFRowPacket();
        lastEof.setPacketId(++packetId);


        lastEof.write(buffer, service);
    }

}
