[PD1] restructure

Projs/PD1/internal/protocol/protocol.go

@@ -0,0 +1,68 @@
+package protocol
+
+import (
+	"encoding/json"
+	"fmt"
+	"time"
+)
+
+type PacketType int
+
+const (
+	ReqPK PacketType = iota
+	ReqAllMsg
+	ReqMsg
+	SendPK
+	UsrMsg
+)
+
+type PacketBody interface {}
+
+type Packet struct {
+	Flag PacketType
+	Body PacketBody
+}
+
+// Client --> Server: Ask for a user's public key
+type RequestPubKey struct {
+	FromUID string
+	KeyUID  string
+}
+
+// Client --> Server: Ask for all the client's messages in the queue
+type RequestAllMsg struct {
+	FromUID string
+}
+
+// Client --> Server: Ask for a specific message in the queue
+type RequestMsg struct {
+	Num     uint16
+}
+
+// Server --> Client: Send the client the requested public key
+type SendPubKey struct {
+	Key     []byte
+}
+
+// Bidirectional: Send messages between server and clients
+type SendMessage struct {
+	ToUID   string
+	Subject []byte
+	Body    []byte
+}
+
+type Message struct {
+    FromUID string
+	ToUID   string
+	Subject []byte
+	Body    []byte
+    Timestamp time.Time
+}
+
+func (p Packet) Marshal() ([]byte, error) {
+    return json.Marshal(p)
+}
+
+func (p *Packet) Unmarshal(data []byte) error {
+	return json.Unmarshal(data, p)
+}