1 files changed, 73 insertions, 0 deletions
diff --git a/src/main/java/org/traccar/protocol/Pt502FrameDecoder.java b/src/main/java/org/traccar/protocol/Pt502FrameDecoder.java
new file mode 100644
index 000000000..316cd987f
--- /dev/null
+++ b/src/main/java/org/traccar/protocol/Pt502FrameDecoder.java
@@ -0,0 +1,73 @@
+/*
+ * Copyright 2014 - 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 io.netty.channel.ChannelHandlerContext;
+import org.traccar.BaseFrameDecoder;
+
+import java.nio.charset.StandardCharsets;
+
+public class Pt502FrameDecoder extends BaseFrameDecoder {
+
+    private static final int BINARY_HEADER = 5;
+
+    @Override
+    protected Object decode(
+            ChannelHandlerContext ctx, Channel channel, ByteBuf buf) throws Exception {
+
+        if (buf.readableBytes() < 10) {
+            return null;
+        }
+
+        if (buf.getUnsignedByte(buf.readerIndex()) == 0xbf
+                && buf.toString(buf.readerIndex() + BINARY_HEADER, 4, StandardCharsets.US_ASCII).equals("$PHD")) {
+
+            int length = buf.getUnsignedShortLE(buf.readerIndex() + 3);
+            if (buf.readableBytes() >= length) {
+                buf.skipBytes(BINARY_HEADER);
+                ByteBuf result = buf.readRetainedSlice(length - BINARY_HEADER - 2);
+                buf.skipBytes(2); // line break
+                return result;
+            }
+
+        } else {
+
+            if (buf.getUnsignedByte(buf.readerIndex()) == 0xbf) {
+                buf.skipBytes(BINARY_HEADER);
+            }
+
+            int index = buf.indexOf(buf.readerIndex(), buf.writerIndex(), (byte) '\r');
+            if (index < 0) {
+                index = buf.indexOf(buf.readerIndex(), buf.writerIndex(), (byte) '\n');
+            }
+
+            if (index > 0) {
+                ByteBuf result = buf.readRetainedSlice(index - buf.readerIndex());
+                while (buf.isReadable()
+                        && (buf.getByte(buf.readerIndex()) == '\r' || buf.getByte(buf.readerIndex()) == '\n')) {
+                    buf.skipBytes(1);
+                }
+                return result;
+            }
+
+        }
+
+        return null;
+    }
+
+}