/*
    * 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.shardingsphere.db.protocol.mysql.packet.binlog.row;
  
  import lombok.Getter;
  import org.apache.shardingsphere.db.protocol.mysql.constant.MySQLBinlogEventType;
  import org.apache.shardingsphere.db.protocol.mysql.packet.binlog.AbstractMySQLBinlogEventPacket;
  import org.apache.shardingsphere.db.protocol.mysql.packet.binlog.MySQLBinlogEventHeader;
  import org.apache.shardingsphere.db.protocol.mysql.packet.binlog.row.column.MySQLBinlogColumnDef;
  import org.apache.shardingsphere.db.protocol.mysql.packet.binlog.row.column.value.MySQLBinlogProtocolValueFactory;
  import org.apache.shardingsphere.db.protocol.mysql.packet.command.query.binary.execute.MySQLNullBitmap;
  import org.apache.shardingsphere.db.protocol.mysql.payload.MySQLPacketPayload;
  
  import java.io.Serializable;
  import java.util.LinkedList;
  import java.util.List;
  
  /**
   * MySQL binlog rows event packet.
   *
   * @see <a href="https://dev.mysql.com/doc/dev/mysql-server/latest/classbinary__log_1_1Rows__event.html">ROWS_EVENT</a>
   * @see <a href="https://mariadb.com/kb/en/rows_event_v1v2-rows_compressed_event_v1/">ROWS_EVENT</a>
   */
  @Getter
  public final class MySQLBinlogRowsEventPacket extends AbstractMySQLBinlogEventPacket {
      
      private final long tableId;
      
      private final int flags;
      
      private final int columnNumber;
      
      private final MySQLNullBitmap columnsPresentBitmap;
      
      private final MySQLNullBitmap columnsPresentBitmap2;
      
      private final List<Serializable[]> rows = new LinkedList<>();
      
      private final List<Serializable[]> rows2 = new LinkedList<>();
      
      public MySQLBinlogRowsEventPacket(final MySQLBinlogEventHeader binlogEventHeader, final MySQLPacketPayload payload) {
          super(binlogEventHeader);
          tableId = payload.readInt6();
          flags = payload.readInt2();
          skipExtraData(payload);
          columnNumber = (int) payload.readIntLenenc();
          columnsPresentBitmap = new MySQLNullBitmap(columnNumber, payload);
          columnsPresentBitmap2 = readUpdateColumnsPresentBitmap(payload);
      }
      
      private void skipExtraData(final MySQLPacketPayload payload) {
          if (isRowsEventVersion2(getBinlogEventHeader().getEventType())) {
              int extraDataLength = payload.readInt2() - 2;
              payload.skipReserved(extraDataLength);
          }
      }
      
      private boolean isRowsEventVersion2(final int eventType) {
          return MySQLBinlogEventType.WRITE_ROWS_EVENT_V2.getValue() == eventType || MySQLBinlogEventType.UPDATE_ROWS_EVENT_V2.getValue() == eventType
                  || MySQLBinlogEventType.DELETE_ROWS_EVENT_V2.getValue() == eventType;
      }
      
      private MySQLNullBitmap readUpdateColumnsPresentBitmap(final MySQLPacketPayload payload) {
          return isUpdateRowsEvent(getBinlogEventHeader().getEventType()) ? new MySQLNullBitmap(columnNumber, payload) : null;
      }
      
      private boolean isUpdateRowsEvent(final int eventType) {
          return MySQLBinlogEventType.UPDATE_ROWS_EVENT_V2.getValue() == eventType || MySQLBinlogEventType.UPDATE_ROWS_EVENT_V1.getValue() == eventType;
      }
      
      /**
       * Read rows in binlog.
       *
       * @param tableMapEventPacket TABLE_MAP_EVENT packet before this ROWS_EVENT
       * @param payload ROWS_EVENT packet payload
       */
      public void readRows(final MySQLBinlogTableMapEventPacket tableMapEventPacket, final MySQLPacketPayload payload) {
          List<MySQLBinlogColumnDef> columnDefs = tableMapEventPacket.getColumnDefs();
          while (getRemainBytesLength(payload) > 0) {
              rows.add(readRow(columnDefs, payload));
              if (isUpdateRowsEvent(getBinlogEventHeader().getEventType())) {
                  rows2.add(readRow(columnDefs, payload));
              }
          }
     }
     
     private Serializable[] readRow(final List<MySQLBinlogColumnDef> columnDefs, final MySQLPacketPayload payload) {
         MySQLNullBitmap nullBitmap = new MySQLNullBitmap(columnNumber, payload);
         Serializable[] result = new Serializable[columnNumber];
         for (int i = 0; i < columnNumber; i++) {
             MySQLBinlogColumnDef columnDef = columnDefs.get(i);
             result[i] = nullBitmap.isNullParameter(i) ? null : MySQLBinlogProtocolValueFactory.getBinlogProtocolValue(columnDef.getColumnType()).read(columnDef, payload);
         }
         return result;
     }
     
     @Override
     protected void writeEvent(final MySQLPacketPayload payload) {
         // TODO
     }
 }