From ac8b60e030841a7170c61fa550d2322fe87577f7 Mon Sep 17 00:00:00 2001
From: mykola2312 <49044616+mykola2312@users.noreply.github.com>
Date: Mon, 30 Dec 2024 10:41:12 +0200
Subject: [PATCH] implement channel recv & send

---
 net/lux_channel.go        | 46 +++++++++++++++++++++++++++++++--------
 net/lux_datagram.go       |  5 +++++
 tests/lux_channel_test.go | 35 +++++++++++++++++++++++++++++
 3 files changed, 77 insertions(+), 9 deletions(-)
 create mode 100644 net/lux_datagram.go
 create mode 100644 tests/lux_channel_test.go

diff --git a/net/lux_channel.go b/net/lux_channel.go
index c3e3295..925f5b6 100644
--- a/net/lux_channel.go
+++ b/net/lux_channel.go
@@ -10,9 +10,10 @@ const (
 )
 
 type LuxChannel struct {
-	Type    LuxChannelType
-	Address *net.UDPAddr
-	conn    *net.UDPConn
+	Type         LuxChannelType
+	Address      *net.UDPAddr
+	conn         *net.UDPConn
+	preconnected bool
 }
 
 // bind udp socket to receive packets
@@ -28,12 +29,14 @@ func NewLuxInboundChannel(udpStr string, chType LuxChannelType) (LuxChannel, err
 	}
 
 	return LuxChannel{
-		Type:    chType,
-		Address: addr,
-		conn:    conn,
+		Type:         chType,
+		Address:      addr,
+		conn:         conn,
+		preconnected: false,
 	}, nil
 }
 
+// udp socket to send datagrams
 func NewLuxOutboundChannel(udpStr string, chType LuxChannelType) (LuxChannel, error) {
 	addr, err := net.ResolveUDPAddr("udp", udpStr)
 	if err != nil {
@@ -46,12 +49,37 @@ func NewLuxOutboundChannel(udpStr string, chType LuxChannelType) (LuxChannel, er
 	}
 
 	return LuxChannel{
-		Type:    chType,
-		Address: addr,
-		conn:    conn,
+		Type:         chType,
+		Address:      addr,
+		conn:         conn,
+		preconnected: true,
 	}, nil
 }
 
+const MAX_UDP_SIZE = 65535
+
+func (ch *LuxChannel) Recv() (LuxDatagram, *net.UDPAddr, error) {
+	buf := make([]byte, MAX_UDP_SIZE)
+	len, addr, err := ch.conn.ReadFromUDP(buf)
+	if err != nil {
+		return LuxDatagram{}, nil, err
+	}
+
+	return LuxDatagram{
+		Payload: buf[:len],
+	}, addr, nil
+}
+
+func (ch *LuxChannel) Send(dgram LuxDatagram, addr *net.UDPAddr) error {
+	if ch.preconnected {
+		_, err := ch.conn.Write(dgram.Payload)
+		return err
+	} else {
+		_, err := ch.conn.WriteToUDP(dgram.Payload, addr)
+		return err
+	}
+}
+
 func (ch *LuxChannel) Close() {
 	ch.conn.Close()
 }
diff --git a/net/lux_datagram.go b/net/lux_datagram.go
new file mode 100644
index 0000000..186fcc2
--- /dev/null
+++ b/net/lux_datagram.go
@@ -0,0 +1,5 @@
+package net
+
+type LuxDatagram struct {
+	Payload []byte
+}
diff --git a/tests/lux_channel_test.go b/tests/lux_channel_test.go
new file mode 100644
index 0000000..b7f362c
--- /dev/null
+++ b/tests/lux_channel_test.go
@@ -0,0 +1,35 @@
+package tests
+
+import (
+	"bytes"
+	"lux/net"
+	"testing"
+)
+
+func TestRecvSend(t *testing.T) {
+	sv, err := net.NewLuxInboundChannel("127.0.0.2:65535", net.LuxChannelInterior)
+	if err != nil {
+		t.Fatal(t)
+	}
+
+	cl, err := net.NewLuxOutboundChannel("127.0.0.2:65535", net.LuxChannelInterior)
+	if err != nil {
+		t.Fatal(t)
+	}
+
+	dgram := net.LuxDatagram{Payload: []byte("TEEEESTTTT 3243492i0423")}
+	if err := cl.Send(dgram, sv.Address); err != nil {
+		t.Fatal(err)
+	}
+
+	recv, _, err := sv.Recv()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if !bytes.Equal(dgram.Payload, recv.Payload) {
+		t.Log(dgram)
+		t.Log(recv)
+		t.Fatal("sent and recv payload not equal!")
+	}
+}