[PD2] Server done?

Co-authored-by: tsousa111 <tiagao2001@hotmail.com>

Projs/PD2/internal/client/datastore.go

@@ -0,0 +1,47 @@
+package client
+
+import (
+	"encoding/json"
+	"time"
+)
+
+type ClientMessage struct {
+	FromUID   string
+	ToUID     string
+	Subject   string
+	Body      string
+	Timestamp time.Time
+}
+
+type ClientMessageInfo struct {
+	Num          int
+	FromUID      string
+	Timestamp    time.Time
+	Subject      string
+	decryptError error
+}
+
+func newClientMessage(fromUID string, toUID string, subject string, body string, timestamp time.Time) ClientMessage {
+	return ClientMessage{FromUID: fromUID, ToUID: toUID, Subject: subject, Body: body, Timestamp: timestamp}
+}
+
+func newClientMessageInfo(num int, fromUID string, subject string, timestamp time.Time, err error) ClientMessageInfo {
+	return ClientMessageInfo{Num: num, FromUID: fromUID, Subject: subject, Timestamp: timestamp, decryptError: err}
+}
+
+func Marshal(data any) ([]byte, error) {
+	subject, err := json.Marshal(data)
+	if err != nil {
+		return nil, err
+	}
+	return subject, nil
+}
+
+func Unmarshal(data []byte) (string, error) {
+	var c string
+	err := json.Unmarshal(data, &c)
+	if err != nil {
+		return "", err
+	}
+	return c, nil
+}