aboutsummaryrefslogtreecommitdiff
path: root/src/main/java/org/traccar/protocol/FleetGuideProtocolDecoder.java
blob: 9fddec922d5d727e43d5102a120f20010aa0cae8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
/*
 * Copyright 2024 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 io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.Channel;
import org.traccar.BaseProtocolDecoder;
import org.traccar.Protocol;
import org.traccar.helper.BitUtil;
import org.traccar.helper.UnitsConverter;
import org.traccar.model.Position;
import org.traccar.session.DeviceSession;

import java.net.SocketAddress;
import java.util.Date;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Set;

public class FleetGuideProtocolDecoder extends BaseProtocolDecoder {

    public FleetGuideProtocolDecoder(Protocol protocol) {
        super(protocol);
    }

    public static final int MSG_DATA = 0x10;
    public static final int MSG_HEARTBEAT = 0x1A;
    public static final int MSG_RESPONSE = 0x1C;

    @Override
    protected Object decode(
            Channel channel, SocketAddress remoteAddress, Object msg) throws Exception {

        ByteBuf buf = (ByteBuf) msg;

        buf.readUnsignedByte(); // signature
        int options = buf.readUnsignedShortLE();
        int length = BitUtil.to(options, 11);

        DeviceSession deviceSession;
        if (BitUtil.check(options, 11)) {
            deviceSession = getDeviceSession(channel, remoteAddress, String.valueOf(buf.readUnsignedIntLE()));
        } else {
            deviceSession = getDeviceSession(channel, remoteAddress);
        }
        if (deviceSession == null) {
            return null;
        }

        int type;
        if (BitUtil.check(options, 12)) {
            type = BitUtil.to(buf.readUnsignedByte(), 4);
        } else {
            type = 0;
        }

        if (BitUtil.check(options, 13)) {
            buf.readUnsignedShortLE(); // acknowledgement
        }

        ByteBuf data;
        if (BitUtil.check(options, 14)) {
            data = decompress(buf.readSlice(length));
        } else {
            data = buf.readRetainedSlice(length);
        }

        List<Position> positions = new LinkedList<>();

        Position position = new Position(getProtocolName());
        position.setDeviceId(deviceSession.getDeviceId());

        Set<Integer> recordTypes = new HashSet<>();

        while (data.isReadable()) {

            int recordHeader = data.readUnsignedShortLE();
            int recordLength = BitUtil.to(recordHeader, 10);
            int recordType = BitUtil.from(recordHeader, 10);
            int recordEndIndex = data.readerIndex() + recordLength;

            if (recordTypes.contains(recordType)) {
                positions.add(processPosition(position));
                position = new Position(getProtocolName());
                position.setDeviceId(deviceSession.getDeviceId());
                recordTypes.clear();
            }
            recordTypes.add(recordType);

            switch (recordType) {
                case 0:
                    position.setTime(new Date((data.readUnsignedIntLE() + 1262304000) * 1000)); // since 2010-01-01
                    break;
                case 1:
                    position.setLatitude(data.readUnsignedIntLE() * 90.0 / 0xFFFFFFFFL);
                    position.setLongitude(data.readUnsignedIntLE() * 180.0 / 0xFFFFFFFFL);
                    int speed = data.readUnsignedShortLE();
                    position.setSpeed(UnitsConverter.knotsFromKph(BitUtil.to(speed, 14) * 0.1));
                    if (BitUtil.check(speed, 14)) {
                        position.setLatitude(-position.getLatitude());
                    }
                    if (BitUtil.check(speed, 15)) {
                        position.setLongitude(-position.getLongitude());
                    }
                    int course = data.readUnsignedShortLE();
                    position.setSpeed(BitUtil.to(course, 9));
                    int motion = BitUtil.between(course, 9, 11);
                    if (motion > 0) {
                        position.set(Position.KEY_MOTION, motion == 1);
                    }
                    position.set(Position.KEY_SATELLITES, BitUtil.from(course, 11));
                    int altitude = data.readUnsignedShortLE();
                    position.setAltitude(BitUtil.to(altitude, 14));
                    if (BitUtil.check(altitude, 14)) {
                        position.setAltitude(-position.getAltitude());
                    }
                    break;
                default:
                    break;
            }

            data.readerIndex(recordEndIndex);

        }

        data.release();

        return positions.isEmpty() ? null : positions;
    }

    private Position processPosition(Position position) {
        if (position.getFixTime() == null) {
            position.setTime(new Date());
        }
        if (!position.getAttributes().containsKey(Position.KEY_SATELLITES)) {
            getLastLocation(position, null);
        }
        return position;
    }

    private int readVarSize(ByteBuf buf) {
        int b;
        int y = 0;
        do {
            b = buf.readUnsignedByte();
            y = (y << 7) | (b & 0x0000007f);
        } while ((b & 0x00000080) > 0);

        return y;
    }

    private ByteBuf decompress(ByteBuf in) {

        ByteBuf out = Unpooled.buffer();

        if (in.readableBytes() < 1) {
            return out;
        }

        int marker = in.readUnsignedByte();

        do {
            int symbol = in.readUnsignedByte();
            if (symbol == marker) {
                if (in.getUnsignedByte(in.readerIndex()) == 0) {
                    out.writeByte(marker);
                    in.skipBytes(1);
                } else {
                    int length = readVarSize(in);
                    int offset = readVarSize(in);

                    for (int i = 0; i < length; i++) {
                        out.writeByte(out.getUnsignedByte(out.writerIndex() - offset));
                    }
                }
            } else {
                out.writeByte(symbol);
            }
        } while (in.isReadable());

        return out;
    }

}