1 files changed, 127 insertions, 0 deletions
diff --git a/src/main/java/org/traccar/protocol/M2mProtocolDecoder.java b/src/main/java/org/traccar/protocol/M2mProtocolDecoder.java
new file mode 100644
index 000000000..21e4a2fd0
--- /dev/null
+++ b/src/main/java/org/traccar/protocol/M2mProtocolDecoder.java
@@ -0,0 +1,127 @@
+/*
+ * Copyright 2013 - 2018 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.channel.Channel;
+import org.traccar.BaseProtocolDecoder;
+import org.traccar.DeviceSession;
+import org.traccar.Protocol;
+import org.traccar.helper.DateBuilder;
+import org.traccar.model.Position;
+
+import java.net.SocketAddress;
+
+public class M2mProtocolDecoder extends BaseProtocolDecoder {
+
+    public M2mProtocolDecoder(Protocol protocol) {
+        super(protocol);
+    }
+
+    private boolean firstPacket = true;
+
+    @Override
+    protected Object decode(
+            Channel channel, SocketAddress remoteAddress, Object msg) throws Exception {
+
+        ByteBuf buf = (ByteBuf) msg;
+
+        // Remove offset
+        for (int i = 0; i < buf.readableBytes(); i++) {
+            int b = buf.getByte(i);
+            if (b != 0x0b) {
+                buf.setByte(i, b - 0x20);
+            }
+        }
+
+        if (firstPacket) {
+
+            firstPacket = false;
+
+            StringBuilder imei = new StringBuilder();
+            for (int i = 0; i < 8; i++) {
+                int b = buf.readByte();
+                if (i != 0) {
+                    imei.append(b / 10);
+                }
+                imei.append(b % 10);
+            }
+
+            getDeviceSession(channel, remoteAddress, imei.toString());
+
+        } else {
+
+            DeviceSession deviceSession = getDeviceSession(channel, remoteAddress);
+            if (deviceSession == null) {
+                return null;
+            }
+
+            Position position = new Position(getProtocolName());
+            position.setDeviceId(deviceSession.getDeviceId());
+
+            DateBuilder dateBuilder = new DateBuilder()
+                    .setDay(buf.readUnsignedByte() & 0x3f)
+                    .setMonth(buf.readUnsignedByte() & 0x3f)
+                    .setYear(buf.readUnsignedByte())
+                    .setHour(buf.readUnsignedByte() & 0x3f)
+                    .setMinute(buf.readUnsignedByte() & 0x7f)
+                    .setSecond(buf.readUnsignedByte() & 0x7f);
+            position.setTime(dateBuilder.getDate());
+
+            int degrees = buf.readUnsignedByte();
+            double latitude = buf.readUnsignedByte();
+            latitude += buf.readUnsignedByte() / 100.0;
+            latitude += buf.readUnsignedByte() / 10000.0;
+            latitude /= 60;
+            latitude += degrees;
+
+            int b = buf.readUnsignedByte();
+
+            degrees = (b & 0x7f) * 100 + buf.readUnsignedByte();
+            double longitude = buf.readUnsignedByte();
+            longitude += buf.readUnsignedByte() / 100.0;
+            longitude += buf.readUnsignedByte() / 10000.0;
+            longitude /= 60;
+            longitude += degrees;
+
+            if ((b & 0x80) != 0) {
+                longitude = -longitude;
+            }
+            if ((b & 0x40) != 0) {
+                latitude = -latitude;
+            }
+
+            position.setValid(true);
+            position.setLatitude(latitude);
+            position.setLongitude(longitude);
+            position.setSpeed(buf.readUnsignedByte());
+
+            int satellites = buf.readUnsignedByte();
+            if (satellites == 0) {
+                return null; // cell information
+            }
+            position.set(Position.KEY_SATELLITES, satellites);
+
+            // decode other data
+
+            return position;
+
+        }
+
+        return null;
+    }
+
+}