Restructure to library

agwpe.go

@@ -0,0 +1,33 @@
+package main
+
+import "encoding/binary"
+
+type Frame struct {
+	Port      byte
+	Reserved0 [3]byte
+	DataKind  byte
+	Reserved1 byte
+	PID       byte
+	Reserved2 byte
+	CallFrom  [10]byte
+	CallTo    [10]byte
+	DataLen   uint32
+	User      [4]byte
+}
+
+func (f *Frame) Serialize() []byte {
+	buf := make([]byte, 36)
+
+	buf[0] = f.Port
+	// Ignore reserved bytes 1 to 3
+	buf[4] = f.DataKind
+	// Ignore reserved byte 5
+	buf[6] = f.PID
+	// Ignore reserved byte 7
+	copy(buf[8:18], f.CallFrom[:])
+	copy(buf[18:28], f.CallTo[:])
+	binary.LittleEndian.PutUint32(buf[28:32], f.DataLen)
+	copy(buf[32:36], f.User[:])
+
+	return buf
+}