/*
Copyright (c) 2013, 2014 Paolo Patierno
All rights reserved. This program and the accompanying materials
are made available under the terms of the Eclipse Public License v1.0
and Eclipse Distribution License v1.0 which accompany this distribution.
The Eclipse Public License is available at
http://www.eclipse.org/legal/epl-v10.html
and the Eclipse Distribution License is available at
http://www.eclipse.org/org/documents/edl-v10.php.
Contributors:
Paolo Patierno - initial API and implementation and/or initial documentation
*/
using uPLibrary.Networking.M2Mqtt.Exceptions;
namespace uPLibrary.Networking.M2Mqtt.Messages
{
///
/// Class for PUBREC message from broker to client
///
public class MqttMsgPubrec : MqttMsgBase
{
///
/// Constructor
///
public MqttMsgPubrec()
{
this.type = MQTT_MSG_PUBREC_TYPE;
}
public override byte[] GetBytes(byte protocolVersion)
{
int fixedHeaderSize = 0;
int varHeaderSize = 0;
int payloadSize = 0;
int remainingLength = 0;
byte[] buffer;
int index = 0;
// message identifier
varHeaderSize += MESSAGE_ID_SIZE;
remainingLength += (varHeaderSize + payloadSize);
// first byte of fixed header
fixedHeaderSize = 1;
int temp = remainingLength;
// increase fixed header size based on remaining length
// (each remaining length byte can encode until 128)
do
{
fixedHeaderSize++;
temp = temp / 128;
} while (temp > 0);
// allocate buffer for message
buffer = new byte[fixedHeaderSize + varHeaderSize + payloadSize];
// first fixed header byte
if (protocolVersion == MqttMsgConnect.PROTOCOL_VERSION_V3_1_1)
buffer[index++] = (MQTT_MSG_PUBREC_TYPE << MSG_TYPE_OFFSET) | MQTT_MSG_PUBREC_FLAG_BITS; // [v.3.1.1]
else
buffer[index++] = (MQTT_MSG_PUBREC_TYPE << MSG_TYPE_OFFSET);
// encode remaining length
index = this.encodeRemainingLength(remainingLength, buffer, index);
// get message identifier
buffer[index++] = (byte)((this.messageId >> 8) & 0x00FF); // MSB
buffer[index++] = (byte)(this.messageId & 0x00FF); // LSB
return buffer;
}
///
/// Parse bytes for a PUBREC message
///
/// First fixed header byte
/// Protocol Version
/// Channel connected to the broker
/// PUBREC message instance
public static MqttMsgPubrec Parse(byte fixedHeaderFirstByte, byte protocolVersion, IMqttNetworkChannel channel)
{
byte[] buffer;
int index = 0;
MqttMsgPubrec msg = new MqttMsgPubrec();
if (protocolVersion == MqttMsgConnect.PROTOCOL_VERSION_V3_1_1)
{
// [v3.1.1] check flag bits
if ((fixedHeaderFirstByte & MSG_FLAG_BITS_MASK) != MQTT_MSG_PUBREC_FLAG_BITS)
throw new MqttClientException(MqttClientErrorCode.InvalidFlagBits);
}
// get remaining length and allocate buffer
int remainingLength = MqttMsgBase.decodeRemainingLength(channel);
buffer = new byte[remainingLength];
// read bytes from socket...
channel.Receive(buffer);
// message id
msg.messageId = (ushort)((buffer[index++] << 8) & 0xFF00);
msg.messageId |= (buffer[index++]);
return msg;
}
public override string ToString()
{
#if TRACE
return this.GetTraceString(
"PUBREC",
new object[] { "messageId" },
new object[] { this.messageId });
#else
return base.ToString();
#endif
}
}
}