sync

]

@@ -0,0 +1,126 @@
+package server
+
+import (
+	"encoding/binary"
+	"fmt"
+	"io"
+	"log"
+	"net"
+	"strconv"
+)
+
+const (
+	MsgKeyPress  uint16 = 1
+	MsgGameState uint16 = 2
+	MSGServerStatus uint16 = 3
+	MSGOnConnect uint16 = 4
+)
+
+var num_clients int = 0
+
+func Start() {
+	listener, err := net.Listen("tcp", ":9000")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	fmt.Println("Server listening on port 9000")
+
+	for {
+		conn, err := listener.Accept()
+		if err != nil {
+			fmt.Println("Accept error:", err)
+			continue
+		}
+
+		num_clients += 1
+		fmt.Println(toString(num_clients))
+		go SendPacket(conn, MSGOnConnect, []byte(string(num_clients)))
+
+		go handle(conn)
+	}
+}
+
+func toString(num int) {
+	return strconv.FormatInt(int64(num), 10)
+}
+
+func SendPacket(conn net.Conn, msgID uint16, payload []byte) error {
+	// Length matches Lua: 2 (msgID) + payload size
+	length := uint32(2 + len(payload))
+	buf := make([]byte, 4+2+len(payload))
+
+	binary.BigEndian.PutUint32(buf[0:4], length)
+	binary.BigEndian.PutUint16(buf[4:6], msgID)
+	copy(buf[6:], payload)
+
+	n, err := conn.Write(buf)
+	if err != nil {
+		return err
+	}
+	if n != len(buf) {
+		return fmt.Errorf("short write: expected %d bytes, got %d", len(buf), n)
+	}
+	return nil
+}
+
+func handle(conn net.Conn) {
+	defer conn.Close()
+
+	for {
+		// Read packet length
+		var length uint32
+
+		err := binary.Read(conn, binary.BigEndian, &length)
+		if err != nil {
+			if err != io.EOF {
+				fmt.Println("Read length error:", err)
+			}
+
+			fmt.Println("Client disconnected")
+			return
+		}
+
+		// Prevent invalid packets
+		if length < 2 {
+			fmt.Println("Invalid packet length:", length)
+			return
+		}
+
+		// Read message ID
+		var msgID uint16
+
+		err = binary.Read(conn, binary.BigEndian, &msgID)
+		if err != nil {
+			fmt.Println("Read message ID error:", err)
+			return
+		}
+
+		// Read payload
+		payload := make([]byte, length-2)
+
+		_, err = io.ReadFull(conn, payload)
+		if err != nil {
+			fmt.Println("Read payload error:", err)
+			return
+		}
+
+		switch msgID {
+
+		case MsgKeyPress:
+			msg := string(payload)
+
+			fmt.Println(msg)
+
+			// Send something back to the client
+			err := SendPacket(conn, MsgGameState, []byte("received key press: "+msg))
+			if err != nil {
+				fmt.Println("Send error:", err)
+				return
+			}
+
+		default:
+			fmt.Println("Unknown message:", msgID)
+		}
+	}
+}

client/init.lua

@@ -7,6 +7,8 @@ local client
 -- Packet IDs
 network.MSG_KEY_PRESS = 1
 network.MSG_GAMESTATE = 2
+network.MSG_SERVER_STATUS = 3
+network.MSG_ON_CONNECT = 4
 
 --------------------------------------------------
 -- Packing

main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"fmt"
 	"grid-mmo-server/server"
 )
 
@@ -13,4 +14,5 @@ type tile struct {
 
 func main() {
 	server.Start()
+	fmt.Print()
 }

main.lua

@@ -5,16 +5,25 @@ local player = {
 	y = 100,
 }
 
+local client_id = 0
+
 function love.load()
 	network.connect("127.0.0.1", 9000)
 
+	network.on(network.MSG_ON_CONNECT, function(payload)
+		print("connected to server with id " .. payload)
+		if client_id == 0 then
+			client_id = payload
+		end
+	end)
+
 	network.on(network.MSG_GAMESTATE, function(payload)
-		print("Server:", payload)
+		print(payload)
 	end)
 end
 
 function love.keypressed(key)
-	network.sendKey(key)
+	network.sendPacket(network.MSG_KEY_PRESS, client_id .. "/pressed/" .. key)
 end
 
 function love.update()
@@ -22,7 +31,7 @@ function love.update()
 end
 
 function love.draw()
-	love.graphics.print("Connected", 20, 20)
+	love.graphics.print("Connected as id " .. client_id, 20, 20)
 
 	love.graphics.circle("fill", player.x, player.y, 10)
 end

server/server.go

@@ -6,13 +6,19 @@ import (
 	"io"
 	"log"
 	"net"
+	"strconv"
 )
 
 const (
 	MsgKeyPress  uint16 = 1
 	MsgGameState uint16 = 2
+	MSGServerStatus uint16 = 3
+	MSGOnConnect uint16 = 4
 )
 
+var num_clients int = 0
+var clients = map[int]net.Conn{}
+
 func Start() {
 	listener, err := net.Listen("tcp", ":9000")
 	if err != nil {
@@ -28,13 +34,21 @@ func Start() {
 			continue
 		}
 
-		fmt.Println("Client connected")
+		num_clients += 1
+		client_id := strconv.Itoa(num_clients)
+		fmt.Println(client_id)
+		go SendPacket(MSGOnConnect, []byte(client_id))
+		addClient(conn, num_clients)
 
 		go handle(conn)
 	}
 }
 
-func SendPacket(conn net.Conn, msgID uint16, payload []byte) error {
+func addClient(conn net.Conn, id int) {
+	clients[id] = conn
+}
+
+func SendPacket(msgID uint16, payload []byte) error {
 	// Length matches Lua: 2 (msgID) + payload size
 	length := uint32(2 + len(payload))
 	buf := make([]byte, 4+2+len(payload))
@@ -43,6 +57,7 @@ func SendPacket(conn net.Conn, msgID uint16, payload []byte) error {
 	binary.BigEndian.PutUint16(buf[4:6], msgID)
 	copy(buf[6:], payload)
 
+	for _, conn := range clients {
 		n, err := conn.Write(buf)
 		if err != nil {
 			return err
@@ -50,6 +65,7 @@ func SendPacket(conn net.Conn, msgID uint16, payload []byte) error {
 		if n != len(buf) {
 			return fmt.Errorf("short write: expected %d bytes, got %d", len(buf), n)
 		}
+	}
 	return nil
 }
 
@@ -67,6 +83,7 @@ func handle(conn net.Conn) {
 			}
 
 			fmt.Println("Client disconnected")
+			num_clients -= 1
 			return
 		}
 
@@ -102,11 +119,7 @@ func handle(conn net.Conn) {
 			fmt.Println(msg)
 
 			// Send something back to the client
-			err := SendPacket(conn, MsgGameState, []byte("received key press: "+msg))
-			if err != nil {
-				fmt.Println("Send error:", err)
-				return
-			}
+			go SendPacket(MsgGameState, []byte(msg))
 
 		default:
 			fmt.Println("Unknown message:", msgID)