1 files changed, 51 insertions, 0 deletions
diff --git a/src/org/traccar/protocol/Arnavi4FrameDecoder.java b/src/org/traccar/protocol/Arnavi4FrameDecoder.java
new file mode 100644
index 000000000..eaf829cc3
--- /dev/null
+++ b/src/org/traccar/protocol/Arnavi4FrameDecoder.java
@@ -0,0 +1,51 @@
+package org.traccar.protocol;
+
+import org.jboss.netty.buffer.ChannelBuffer;
+import org.jboss.netty.channel.Channel;
+import org.jboss.netty.channel.ChannelHandlerContext;
+import org.jboss.netty.handler.codec.frame.FrameDecoder;
+
+/**
+ * Created by Ivan Muratov @binakot on 12.07.2017.
+ */
+public class Arnavi4FrameDecoder extends FrameDecoder {
+
+    static final byte HEADER_START_SIGN = (byte)0xFF;
+    static final byte HEADER_VERSION_1 = 0x22;
+    static final byte HEADER_VERSION_2 = 0x23;
+    static final int HEADER_LENGTH = 10;
+
+    static final byte PACKAGE_START_SIGN = 0x5B;
+    static final byte PACKAGE_END_SIGN = 0x5D;
+    static final int PACKAGE_MIN_PARCEL_NUMBER = 0x01;
+    static final int PACKAGE_MAX_PARCEL_NUMBER = 0xFB;
+
+    @Override
+    protected Object decode(
+            ChannelHandlerContext ctx,
+            Channel channel,
+            ChannelBuffer buf) throws Exception {
+
+        if (buf.readableBytes() == 0) {
+            return null;
+        }
+
+        byte[] bytes = new byte[buf.readableBytes()];
+        buf.getBytes(0, bytes);
+
+        if (bytes[0] == HEADER_START_SIGN
+                && bytes.length == HEADER_LENGTH
+                && (bytes[1] == HEADER_VERSION_1 || bytes[1] == HEADER_VERSION_2)) {
+            return buf.readBytes(HEADER_LENGTH);
+        }
+
+        int parcelNumber = bytes[1] & 0xFF;
+        if (bytes[0] == PACKAGE_START_SIGN && bytes[bytes.length - 1] == PACKAGE_END_SIGN
+                && parcelNumber >= PACKAGE_MIN_PARCEL_NUMBER && parcelNumber <= PACKAGE_MAX_PARCEL_NUMBER) {
+            return buf.readBytes(bytes.length);
+        }
+
+        return null;
+    }
+
+}