From b943ce13c0238b761c67c20c46550e81ead9b419 Mon Sep 17 00:00:00 2001
From: Justin T <37750742+jtieri@users.noreply.github.com>
Date: Sat, 30 Nov 2019 00:11:13 -0600
Subject: [PATCH] overhaul of packet parsing & updated sessions

Listen was updated to better parse incoming packets from sessions so that junk data is handled as well as clients disconnecting. Basic means of writing packets to a session were also implemented.
---
 habbgo/server/session.go | 65 +++++++++++++++++++++++++++++-----------
 1 file changed, 47 insertions(+), 18 deletions(-)

diff --git a/habbgo/server/session.go b/habbgo/server/session.go
index 900f847..3af85e8 100644
--- a/habbgo/server/session.go
+++ b/habbgo/server/session.go
@@ -3,51 +3,80 @@ package server
 import (
 	"bufio"
 	"github.com/jtieri/HabbGo/habbgo/server/protocol/packets"
+	"github.com/jtieri/HabbGo/habbgo/utils/encoding"
 	"log"
 	"net"
 )
 
 type Session struct {
 	connection net.Conn
-	buffer bufio.Writer
+	buffer     bufio.Writer
 	server     *server
 }
 
 // Listen starts listening for incoming data from a Session and handles it appropriately.
 func (session *Session) Listen() {
+	// TODO Create Player
+
 	reader := bufio.NewReader(session.connection)
 
+	// TODO Send HELLO packet to initialize connection
+
 	// Main loop for listening for incoming packets from a players session
 	for {
-		var rawPacket []byte
-		_, err := reader.Read(rawPacket)
-		if err != nil {
-			// TODO handle errors reading packets
-		}
-		log.Println(rawPacket) // TODO REMOVE THIS DUMB TEST
+		// Attempt to read three bytes; client->server packets in FUSEv0.2.0 begin with 3 byte B64 encoded length.
+		encodedLen := make([]byte, 3)
+		for i := 0; i < 3; i++ {
+			b, err := reader.ReadByte()
 
-		// Decode raw rawPacket & if acceptable
-		if packets.VerifyIncoming(rawPacket) {
-			// Create an incoming packet struct with remaining bytes in rawPacket
-			// TODO handle packets coming in from player's Sessions
+			if err != nil {
+				// TODO handle errors reading packets
+				session.Close()
+				return
+			}
+			encodedLen[i] = b
 		}
+		length := encoding.DecodeB64(encodedLen)
+
+		// Get Base64 encoded packet header
+		rawHeader := make([]byte, 2)
+		for i := 0; i < 2; i++ {
+			rawHeader[i], _ = reader.ReadByte()
+		}
+
+		// Check if data is junk before handling
+		var rawPacket []byte
+		bytesRead, err := reader.Read(rawPacket)
+		if length == 0 || err != nil || bytesRead < length {
+			// TODO handle logging junk packets
+			continue
+		}
+
+		// Create a struct for the packet, and pass it on to be handled.
+		packet := packets.NewIncoming(rawHeader, rawPacket)
+		log.Printf("Received packet %v with contents: %v ", packet.HeaderId, packet.Payload.String()) // TODO REMOVE THIS DUMB TEST
+		// TODO handle packets coming in from player's Session
 	}
 }
 
-func (session *Session) Send() {
-	// Write
-	// Flush
+func (session *Session) Send(packet *packets.OutgoingPacket) {
+	packet.Finish()
+	session.buffer.Write(packet.Payload.Bytes())
+	session.buffer.Flush()
 }
 
-func (session *Session) Queue() {
-	// Write
+func (session *Session) Queue(packet *packets.OutgoingPacket) {
+	packet.Finish()
+	session.buffer.Write(packet.Payload.Bytes())
 }
 
-func (session *Session) Flush() {
-	// Flush
+func (session *Session) Flush(packet *packets.OutgoingPacket) {
+	session.buffer.Flush()
 }
 
 // Close disconnects a Session from the server.
 func (session *Session) Close() {
+	session.server.RemoveSession(session)
+	session.server = nil
 	session.connection.Close()
 }