/*
Copyright_License {
Copyright (C) 2012 Max Kellermann <max@duempel.org>
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
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 Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
}
*/
package com.geeksville.location;
import java.io.ByteArrayOutputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.DatagramSocket;
import java.net.DatagramPacket;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.SocketAddress;
import java.net.SocketException;
import java.net.UnknownHostException;
import java.util.Calendar;
import java.util.GregorianCalendar;
import java.util.TimeZone;
import android.os.SystemClock;
import android.util.Log;
class CRC16CCITT {
private static final int[] table = new int[]{
0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
0x1231, 0x0210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6,
0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de,
0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485,
0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d,
0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4,
0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc,
0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823,
0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b,
0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12,
0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a,
0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41,
0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49,
0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70,
0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78,
0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f,
0x1080, 0x00a1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e,
0x02b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256,
0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d,
0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c,
0x26d3, 0x36f2, 0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634,
0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab,
0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3,
0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a,
0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92,
0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9,
0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1,
0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8,
0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0
};
static short update(byte octet, short crc) {
return (short)((crc << 8) ^ table[((crc >> 8) ^ octet) & 0xff]);
}
static short update(byte[] data, short crc) {
for (int i = 0; i < data.length; ++i)
crc = update(data[i], crc);
return crc;
}
}
/**
* Writes tracks to the SkyLines server.
*
* @author Max Kellermann <max@duempel.org>
* @see http://git.xcsoar.org/cgit/master/xcsoar.git/tree/src/Tracking/SkyLines/Protocol.hpp
*/
public class SkyLinesTrackingWriter implements PositionWriter {
private static final int MAGIC = 0x5df4b67b;
private static final short TYPE_FIX = 0x3;
private static final int FLAG_LOCATION = 0x1;
private static final int FLAG_TRACK = 0x2;
private static final int FLAG_GROUND_SPEED = 0x4;
private static final int FLAG_AIRSPEED = 0x8;
private static final int FLAG_ALTITUDE = 0x10;
private static final int FLAG_VARIO = 0x20;
private static final int FLAG_ENL = 0x40;
private long key;
private int intervalMS;
private DatagramSocket socket;
private SocketAddress serverAddress;
private DatagramPacket datagram;
private long nextUpdateTime = SystemClock.elapsedRealtime();
private Calendar calendar = new GregorianCalendar(TimeZone.getTimeZone("GMT"));
/**
* Constructor
*
* @param key the SkyLines live tracking key
* @throws Exception
*/
public SkyLinesTrackingWriter(long _key, int _intervalS)
throws SocketException, UnknownHostException {
key = _key;
intervalMS = _intervalS * 1000;
socket = new DatagramSocket();
/* TODO: hard-coded IP address */
InetAddress serverIP = InetAddress.getByName("78.47.50.46");
serverAddress = new InetSocketAddress(serverIP, 5597);
}
private void writeHeader(DataOutputStream dos, short type)
throws IOException {
dos.writeInt(MAGIC);
dos.writeShort(0); // CRC
dos.writeShort(type);
dos.writeLong(key);
}
private void calculateCRC(byte[] data) {
short crc = CRC16CCITT.update(data, (short)0);
data[4] = (byte)(crc >> 8);
data[5] = (byte)crc;
}
private void writeAngle(DataOutputStream dos, double value)
throws IOException {
dos.writeInt((int)(value * 1000000));
}
private void writeGeoPoint(DataOutputStream dos,
double latitude, double longitude)
throws IOException {
writeAngle(dos, latitude);
writeAngle(dos, longitude);
}
private void writeFix(DataOutputStream dos,
int time, double latitude, double longitude,
int altitude, int track, int groundSpeed)
throws IOException {
writeHeader(dos, TYPE_FIX);
dos.writeInt(FLAG_LOCATION|FLAG_TRACK|FLAG_GROUND_SPEED|
FLAG_ALTITUDE);
dos.writeInt(time);
writeGeoPoint(dos, latitude, longitude);
dos.writeInt(0); // reserved
dos.writeShort(track);
dos.writeShort(groundSpeed);
dos.writeShort(0); // airspeed (unavailable)
dos.writeShort(altitude);
dos.writeShort(0); // vario (unavailable)
dos.writeShort(0); // engine noise level (unavailable)
}
private void sendFix(int time, double latitude, double longitude,
int altitude, int track, int groundSpeed)
throws IOException {
ByteArrayOutputStream baos = new ByteArrayOutputStream(48);
DataOutputStream dos = new DataOutputStream(baos);
writeFix(dos, time, latitude, longitude, altitude,
track, groundSpeed);
byte[] data = baos.toByteArray();
assert(data.length == 48);
calculateCRC(data);
if (datagram == null)
datagram = new DatagramPacket(data, data.length,
serverAddress);
else
/* reuse old object to reduce GC pressure */
datagram.setData(data);
socket.send(datagram);
}
@Override
public void emitProlog() {
}
@Override
public void emitPosition(long time, double latitude, double longitude,
float altitude, int bearing,
float groundSpeed, float []accel,
float vspd) {
try {
long now = SystemClock.elapsedRealtime();
if (now >= nextUpdateTime) {
calendar.setTimeInMillis(time);
int second_of_day =
calendar.get(Calendar.HOUR_OF_DAY) * 3600
+ calendar.get(Calendar.MINUTE) * 60
+ calendar.get(Calendar.SECOND);
int ms_of_day = second_of_day * 1000
+ calendar.get(Calendar.MILLISECOND);
sendFix(ms_of_day, latitude, longitude,
(int)altitude, bearing,
(int)(groundSpeed / 3.6));
nextUpdateTime = now + intervalMS;
}
} catch (IOException ex) {
Log.e("SkyLines", "Error", ex);
}
}
@Override
public void emitEpilog() {
}
}