1 files changed, 91 insertions, 0 deletions
diff --git a/m4p/message.go b/m4p/message.go
new file mode 100644
index 0000000..34a9383
--- /dev/null
+++ b/m4p/message.go
@@ -0,0 +1,91 @@
+package m4p
+
+import (
+	"bytes"
+	"encoding/json"
+)
+
+type MessageType string
+
+// MessageType enums.
+const (
+	Magic4PCAdMessage   MessageType = "magic4pc_ad"
+	SubSensorMessage    MessageType = "sub_sensor"
+	RemoteUpdateMessage MessageType = "remote_update"
+	InputMessage        MessageType = "input"
+	KeepAliveMessage    MessageType = "keepalive"
+)
+
+// Message format sent over the wire.
+type Message struct {
+	Type    MessageType `json:"t"`
+	Version int         `json:"version"`
+	*DeviceInfo
+	*Register
+	*RemoteUpdate
+	*Input
+}
+
+// NewMessage initializes a message with the type and protocol version.
+func NewMessage(typ MessageType) Message {
+	return Message{
+		Type:    typ,
+		Version: protocolVersion,
+	}
+}
+
+// DeviceInfo represents a magic4pc server.
+type DeviceInfo struct {
+	Model  string `json:"model"`
+	IPAddr string `json:"-"`
+	Port   int    `json:"port"`
+	MAC    string `json:"mac"`
+}
+
+// Register payload for registering a new client on the server.
+type Register struct {
+	UpdateFrequency int      `json:"updateFreq"`
+	Filter          []string `json:"filter"`
+}
+
+// Input event (key pressed).
+type Input struct {
+	Parameters struct {
+		KeyCode int  `json:"keyCode"`
+		IsDown  bool `json:"isDown"`
+	} `json:"parameters"`
+}
+
+// RemoteUpdate event, sensor data from the magic remote.
+type RemoteUpdate struct {
+	// filters []string
+	Payload []byte `json:"payload"`
+}
+
+// type (
+// 	ReturnValue  uint8
+// 	DeviceID     uint8
+// 	Coordinates  struct{ X, Y int32 }
+// 	Gyroscope    struct{ X, Y, Z float32 }
+// 	Acceleration struct{ X, Y, Z float32 }
+// 	Quaternion   struct{ Q0, Q1, Q2, Q3 float32 }
+// )
+
+// func (ru RemoteUpdate) Coordinates() Coordinates {
+// 	return Coordinates{}
+// }
+
+// func (ru RemoteUpdate) Acceleration() Acceleration {
+// 	return Acceleration{}
+// }
+
+func decode(b []byte) (Message, error) {
+	var m Message
+	dec := json.NewDecoder(bytes.NewReader(b))
+	dec.DisallowUnknownFields()
+	if err := dec.Decode(&m); err != nil {
+		return Message{}, err
+	}
+
+	return m, nil
+}