package org.metricshub.ipmi.core.coding.payload.sol;
   
   /*-
    * ╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲
    * IPMI Java Client
    * ჻჻჻჻჻჻
    * Copyright 2023 Verax Systems, MetricsHub
    * ჻჻჻჻჻჻
    * This program is free software: you can redistribute it and/or modify
   * it under the terms of the GNU Lesser General Public License as
   * published by the Free Software Foundation, either version 3 of the
   * License, or (at your option) any later version.
   *
   * 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 General Lesser Public License for more details.
   *
   * You should have received a copy of the GNU General Lesser Public
   * License along with this program.  If not, see
   * <http://www.gnu.org/licenses/lgpl-3.0.html>.
   * ╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱
   */
  
  import org.metricshub.ipmi.core.coding.payload.IpmiPayload;
  import org.metricshub.ipmi.core.common.MessageComposer;
  import org.metricshub.ipmi.core.common.TypeConverter;
  
  /**
   * Implementation of {@link IpmiPayload} for SOL (Serial over LAN) messages.
   */
  public abstract class SolMessage extends IpmiPayload {
  
      public static final byte MIN_SEQUENCE_NUMBER = 1;
      public static final byte MAX_SEQUENCE_NUMBER = 15;
  
      private static final int PACKET_SEQUENCE_NUMBER_LENGTH = 1;
      private static final int PACKET_ACK_SEQUENCE_NUMBER_LENGTH = 1;
      private static final int ACCEPTED_CHARACTERS_LENGTH = 1;
      private static final int OPERATION_STATUS_LENGTH = 1;
  
      public static final int PAYLOAD_HEADER_LENGTH =
              PACKET_SEQUENCE_NUMBER_LENGTH +
              PACKET_ACK_SEQUENCE_NUMBER_LENGTH +
              ACCEPTED_CHARACTERS_LENGTH +
              OPERATION_STATUS_LENGTH;
  
      /**
       * Sequence number of this packet.
       */
      private final byte sequenceNumber;
  
      /**
       * Sequence number of packet being ACKd/NACKd by this packet.
       */
      private final byte ackNackSequenceNumber;
  
      /**
       * Number of characters being accepted from ACKd/NACKd packet.
       */
      private final byte acceptedCharacterCount;
  
      /**
       * Operation to invoke or status of previously send packet.
       */
      private final byte operationStatus;
  
      protected SolMessage(byte sequenceNumber, byte ackNackSequenceNumber, byte acceptedCharacterCount, byte operationStatus) {
          this.sequenceNumber = trimSequenceNumber(sequenceNumber);
          this.ackNackSequenceNumber = trimSequenceNumber(ackNackSequenceNumber);
          this.acceptedCharacterCount = acceptedCharacterCount;
          this.operationStatus = operationStatus;
      }
  
      /**
       * Trims given sequence number to max allowed value for sequence numbers, applying MAX_SEQUENCE_NUMBER mask on it.
       *
       * @param sequenceNumber
       *          Sequence number before trim
       * @return trimmed sequence number
       */
      private byte trimSequenceNumber(byte sequenceNumber) {
          return TypeConverter.intToByte(sequenceNumber & MAX_SEQUENCE_NUMBER);
      }
  
      @Override
      public byte[] getPayloadData() {
          return MessageComposer.get(getPayloadLength())
              .appendField(sequenceNumber)
              .appendField(ackNackSequenceNumber)
              .appendField(acceptedCharacterCount)
              .appendField(operationStatus)
              .appendField(getData())
              .getMessage();
      }
  
      @Override
      public int getPayloadLength() {
          return PAYLOAD_HEADER_LENGTH + getData().length;
     }
 
     @Override
     public byte[] getIpmiCommandData() {
         return getData();
     }
 
     @Override
     public byte[] getData() {
         byte[] data = super.getData();
 
         if (data == null) {
             return new byte[0];
         }
 
         return data;
     }
 
     public byte getSequenceNumber() {
         return sequenceNumber;
     }
 
     public byte getAckNackSequenceNumber() {
         return ackNackSequenceNumber;
     }
 
     public byte getAcceptedCharacterCount() {
         return acceptedCharacterCount;
     }
 
     /**
      * Checks if given message carries some data (or operation/status).
      */
     public boolean isDataCarrier() {
         return sequenceNumber != 0 || getData().length > 0;
     }
 
     /**
      * Checks if given {@link SolMessage} is an ACK/NACK for some other message.
      */
     public boolean isAcknowledgeMessage() {
         return ackNackSequenceNumber != 0;
     }
 }