Merge branch 'msg-backend'

This adds the XMPP functionality to send and receive XMPP text messages
in one-to-one chats.

2 files changed, 49 insertions, 0 deletions

diff --git a/xmpp/message.go b/xmpp/message.go
new file mode 100644
index 0000000..e1ff8b6
--- /dev/null
+++ b/xmpp/message.go
@@ -0,0 +1,45 @@
+package xmpp
+
+import (
+	"encoding/xml"
+	"fmt"
+	"log"
+	"math/rand"
+)
+
+type message struct {
+	XMLName xml.Name `xml:"jabber:client message"`
+	Type    string   `xml:"type,attr,omitempty"`
+	Id      string   `xml:"id,attr,omitempty"`
+	From    string   `xml:"from,attr,omitempty"`
+	To      string   `xml:"to,attr,omitempty"`
+	// FIXME The lang attribute should have the `xml` prefix for the standard
+	// XML namespace. There was no option found so far which allows this with
+	// the standard library XML implementation and the xml.Encoder.Encode(v
+	// any) function.
+	Lang string `xml:"lang,attr,omitempty"`
+	Body string `xml:"body,omitempty"`
+}
+
+func handleMessage(s *session, m message) {
+	if m.Type == "chat" && m.Body != "" {
+		reply := fmt.Sprintf("Got %s", m.Body)
+		err := s.sendMessage(reply, m.From)
+		if err != nil {
+			log.Printf("Could not send message: %v\n", err)
+		}
+	}
+}
+
+func (s *session) sendMessage(m, j string) error {
+	msg := message{
+		From: s.jid,
+		Id:   fmt.Sprintf("%016x", rand.Uint64()),
+		To:   j,
+		Type: "chat",
+		Lang: "en",
+		Body: m,
+	}
+
+	return s.tx.Encode(msg)
+}
diff --git a/xmpp/routing.go b/xmpp/routing.go
index 5cd2040..2f2347a 100644
--- a/xmpp/routing.go
+++ b/xmpp/routing.go
@@ -13,6 +13,8 @@ func route(s *xml.StartElement, d *xml.Decoder, c chan<- any) {
 		parse(saslSuccess{}, s, d, c)
 	case xml.Name{`jabber:client`, `iq`}:
 		parse(iqResponse{}, s, d, c)
+	case xml.Name{`jabber:client`, `message`}:
+		parse(message{}, s, d, c)
 	default:
 		d.Skip()
 	}
@@ -35,6 +37,8 @@ func handle(s *session, element any) {
 		handleSaslSuccess(s)
 	case iqResponse:
 		handleIqResponse(s, t)
+	case message:
+		handleMessage(s, t)
 	default:
 		log.Printf("Unknown parsed element: %v", t)
 	}