From 18cd4ff9e3a3140c55c517678a96c3e69fe7bb44 Mon Sep 17 00:00:00 2001
From: jbergner <jbergner@send.nrw>
Date: Thu, 14 Aug 2025 19:36:41 +0200
Subject: [PATCH] bugfix

---
 main.go | 100 +++++++++++++++++++++++++++++++++++++++++++++++++-------
 1 file changed, 89 insertions(+), 11 deletions(-)

diff --git a/main.go b/main.go
index 8b82b8b..6dcc2d0 100644
--- a/main.go
+++ b/main.go
@@ -150,6 +150,7 @@ func main() {
 	// Interaction-Handler
 	s := &Server{dg: dg, db: db, tmpl: template.Must(template.New("page").Parse(page))}
 	dg.AddHandler(s.onInteraction)
+	dg.AddHandler(onGuildCreate)
 
 	// Öffnen
 	if err := dg.Open(); err != nil {
@@ -196,6 +197,53 @@ func main() {
 	_ = db.Close()
 }
 
+func onGuildCreate(s *discordgo.Session, g *discordgo.GuildCreate) {
+	chID := findWritableTextChannel(s, g.Guild)
+	if chID == "" {
+		return
+	}
+
+	embed := &discordgo.MessageEmbed{
+		Title:       "👋 Willkommen!",
+		Description: "Ich kann dir Updates per DM schicken.\n\n• Tippe `/subscribe` oder\n• klicke den Button unten, um eine DM mit mir zu starten.",
+		Color:       0x5865F2,
+	}
+
+	components := []discordgo.MessageComponent{
+		discordgo.ActionsRow{
+			Components: []discordgo.MessageComponent{
+				discordgo.Button{
+					CustomID: "start_dm",
+					Label:    "DM starten",
+					Style:    discordgo.PrimaryButton,
+				},
+			},
+		},
+	}
+
+	_, _ = s.ChannelMessageSendComplex(chID, &discordgo.MessageSend{
+		Embed:      embed,
+		Components: components,
+	})
+}
+
+func findWritableTextChannel(s *discordgo.Session, g *discordgo.Guild) string {
+	chs, err := s.GuildChannels(g.ID)
+	if err != nil {
+		return ""
+	}
+	for _, c := range chs {
+		if c.Type == discordgo.ChannelTypeGuildText {
+			// Grober Check: hat der Bot Sende-Recht in diesem Channel?
+			perms, err := s.State.UserChannelPermissions(s.State.User.ID, c.ID)
+			if err == nil && (perms&discordgo.PermissionSendMessages) != 0 {
+				return c.ID
+			}
+		}
+	}
+	return ""
+}
+
 func initDB(db *sql.DB) error {
 	_, err := db.Exec(`
 CREATE TABLE IF NOT EXISTS subscribers (
@@ -207,9 +255,50 @@ CREATE TABLE IF NOT EXISTS subscribers (
 	return err
 }
 
+func respondEphemeral(dg *discordgo.Session, i *discordgo.InteractionCreate, content string) {
+	_ = dg.InteractionRespond(i.Interaction, &discordgo.InteractionResponse{
+		Type: discordgo.InteractionResponseChannelMessageWithSource,
+		Data: &discordgo.InteractionResponseData{
+			Content: content,
+			Flags:   discordgo.MessageFlagsEphemeral,
+		},
+	})
+}
+
+func sendDM(dg *discordgo.Session, userID, content string) error {
+	ch, err := dg.UserChannelCreate(userID)
+	if err != nil {
+		return err
+	}
+	_, err = dg.ChannelMessageSend(ch.ID, content)
+	return err
+}
+
 // onInteraction verarbeitet Slash-Commands (/subscribe, /unsubscribe)
 // und den User-Kontext-Command („Zu Empfängern hinzufügen“).
 func (s *Server) onInteraction(_ *discordgo.Session, i *discordgo.InteractionCreate) {
+
+	if i.Type == discordgo.InteractionMessageComponent {
+		switch i.MessageComponentData().CustomID {
+		case "start_dm":
+			u := actor(i)
+			if u == nil {
+				respondEphemeral(s.dg, i, "Konnte dich nicht ermitteln.")
+				return
+			}
+
+			// optional: in DB aufnehmen
+			// _ = s.addSub(u.ID, userLabel(u))
+
+			if err := sendDM(s.dg, u.ID, "Hey! Schön, dass du da bist. Ab jetzt kann ich dir DMs schicken. ✨"); err != nil {
+				respondEphemeral(s.dg, i, "DM konnte nicht zugestellt werden (Privacy-Einstellungen?).")
+				return
+			}
+			respondEphemeral(s.dg, i, "Ich habe dir eine DM geschickt. 👍")
+			return
+		}
+	}
+
 	// Nur Application-Commands behandeln
 	if i.Type != discordgo.InteractionApplicationCommand {
 		return
@@ -476,14 +565,3 @@ func (s *Server) listSubs(limit int) ([]subRow, error) {
 	}
 	return out, nil
 }
-
-// ---- DM Helper ----
-
-func sendDM(s *discordgo.Session, userID, msg string) error {
-	ch, err := s.UserChannelCreate(userID)
-	if err != nil {
-		return err
-	}
-	_, err = s.ChannelMessageSend(ch.ID, msg)
-	return err
-}