/*
* Copyright 2012 Anton Tananaev (anton.tananaev@gmail.com)
*
* 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 java.util.Calendar;
import java.util.Properties;
import java.util.TimeZone;
import org.jboss.netty.buffer.ChannelBuffer;
import org.jboss.netty.buffer.ChannelBuffers;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelHandlerContext;
import org.traccar.BaseProtocolDecoder;
import org.traccar.database.DataManager;
import org.traccar.helper.Log;
import org.traccar.model.ExtendedInfoFormatter;
import org.traccar.model.Position;
public class Gt02ProtocolDecoder extends BaseProtocolDecoder {
public Gt02ProtocolDecoder(DataManager dataManager, String protocol, Properties properties) {
super(dataManager, protocol, properties);
}
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();
}
private static final int MSG_HEARTBEAT = 0x1A;
private static final int MSG_DATA = 0x10;
@Override
protected Object decode(
ChannelHandlerContext ctx, Channel channel, Object msg)
throws Exception {
ChannelBuffer buf = (ChannelBuffer) msg;
buf.skipBytes(2); // header
buf.readByte(); // size
// Zero for location messages
buf.readByte(); // voltage
buf.readByte(); // gsm signal
String imei = readImei(buf);
long index = buf.readUnsignedShort();
int type = buf.readUnsignedByte();
if (type == MSG_HEARTBEAT) {
if (channel != null) {
byte[] response = {0x54, 0x68, 0x1A, 0x0D, 0x0A};
channel.write(ChannelBuffers.wrappedBuffer(response));
}
}
else if (type == MSG_DATA) {
// Create new position
Position position = new Position();
ExtendedInfoFormatter extendedInfo = new ExtendedInfoFormatter(getProtocol());
extendedInfo.set("index", index);
// Get device id
try {
position.setDeviceId(getDataManager().getDeviceByImei(imei).getId());
} catch(Exception error) {
Log.warning("Unknown device - " + imei);
}
// Date and time
Calendar time = Calendar.getInstance(TimeZone.getTimeZone("UTC"));
time.clear();
time.set(Calendar.YEAR, 2000 + buf.readUnsignedByte());
time.set(Calendar.MONTH, buf.readUnsignedByte() - 1);
time.set(Calendar.DAY_OF_MONTH, buf.readUnsignedByte());
time.set(Calendar.HOUR_OF_DAY, buf.readUnsignedByte());
time.set(Calendar.MINUTE, buf.readUnsignedByte());
time.set(Calendar.SECOND, buf.readUnsignedByte());
position.setTime(time.getTime());
// Latitude
double latitude = buf.readUnsignedInt() / (60.0 * 30000.0);
// Longitude
double longitude = buf.readUnsignedInt() / (60.0 * 30000.0);
// Speed
position.setSpeed((double) buf.readUnsignedByte());
// Course
position.setCourse((double) buf.readUnsignedShort());
buf.skipBytes(3); // reserved
// Flags
long flags = buf.readUnsignedInt();
position.setValid((flags & 0x1) == 0x1);
if ((flags & 0x2) == 0) latitude = -latitude;
if ((flags & 0x4) == 0) longitude = -longitude;
position.setLatitude(latitude);
position.setLongitude(longitude);
position.setAltitude(0.0);
position.setExtendedInfo(extendedInfo.toString());
return position;
}
return null;
}
}