/*
* Copyright 2015 Anton Tananaev (anton@traccar.org)
*
* Licensed 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.traccar.protocol;
import org.jboss.netty.buffer.ChannelBuffer;
import org.jboss.netty.buffer.ChannelBuffers;
import org.jboss.netty.channel.Channel;
import org.traccar.BaseProtocolDecoder;
import org.traccar.DeviceSession;
import org.traccar.helper.DateBuilder;
import org.traccar.model.CellTower;
import org.traccar.model.Network;
import org.traccar.model.Position;
import java.net.SocketAddress;
public class Avl301ProtocolDecoder extends BaseProtocolDecoder {
public Avl301ProtocolDecoder(Avl301Protocol protocol) {
super(protocol);
}
private String readImei(ChannelBuffer buf) {
int b = buf.readUnsignedByte();
StringBuilder imei = new StringBuilder();
imei.append(b & 0x0F);
for (int i = 0; i < 7; i++) {
b = buf.readUnsignedByte();
imei.append((b & 0xF0) >> 4);
imei.append(b & 0x0F);
}
return imei.toString();
}
public static final int MSG_LOGIN = 'L';
public static final int MSG_STATUS = 'H';
public static final int MSG_GPS_LBS_STATUS = '$';
private void sendResponse(Channel channel, int type) {
if (channel != null) {
ChannelBuffer response = ChannelBuffers.directBuffer(5);
response.writeByte('$');
response.writeByte(type);
response.writeByte('#');
response.writeByte('\r'); response.writeByte('\n');
channel.write(response);
}
}
@Override
protected Object decode(
Channel channel, SocketAddress remoteAddress, Object msg) throws Exception {
ChannelBuffer buf = (ChannelBuffer) msg;
buf.skipBytes(1); // header
int type = buf.readUnsignedByte();
buf.readUnsignedByte(); // length
if (type == MSG_LOGIN) {
DeviceSession deviceSession = getDeviceSession(channel, remoteAddress, readImei(buf));
if (deviceSession == null) {
sendResponse(channel, type);
}
} else if (type == MSG_STATUS) {
sendResponse(channel, type);
} else if (type == MSG_GPS_LBS_STATUS) {
DeviceSession deviceSession = getDeviceSession(channel, remoteAddress);
if (deviceSession == null) {
return null;
}
Position position = new Position();
position.setDeviceId(deviceSession.getDeviceId());
position.setProtocol(getProtocolName());
DateBuilder dateBuilder = new DateBuilder()
.setDate(buf.readUnsignedByte(), buf.readUnsignedByte(), buf.readUnsignedByte())
.setTime(buf.readUnsignedByte(), buf.readUnsignedByte(), buf.readUnsignedByte());
position.setTime(dateBuilder.getDate());
int gpsLength = buf.readUnsignedByte(); // gps len and sat
position.set(Position.KEY_SATELLITES, gpsLength & 0xf);
position.set(Position.KEY_SATELLITES_VISIBLE, buf.readUnsignedByte()); // satellites
double latitude = buf.readUnsignedInt() / 600000.0;
double longitude = buf.readUnsignedInt() / 600000.0;
position.setSpeed(buf.readUnsignedByte());
int union = buf.readUnsignedShort(); // course and flags
position.setCourse(union & 0x03FF);
position.setValid((union & 0x1000) != 0);
if ((union & 0x0400) != 0) {
latitude = -latitude;
}
if ((union & 0x0800) != 0) {
longitude = -longitude;
}
position.setLatitude(latitude);
position.setLongitude(longitude);
if ((union & 0x4000) != 0) {
position.set("acc", (union & 0x8000) != 0);
}
position.setNetwork(new Network(
CellTower.fromLacCid(buf.readUnsignedShort(), buf.readUnsignedMedium())));
position.set(Position.KEY_ALARM, Position.ALARM_GENERAL);
int flags = buf.readUnsignedByte();
position.set("acc", (flags & 0x2) != 0);
// parse other flags
position.set(Position.KEY_POWER, buf.readUnsignedByte());
position.set(Position.KEY_RSSI, buf.readUnsignedByte());
return position;
}
return null;
}
}