Send an error presence when the connection to the IRC server fails

src/bridge/bridge.cpp

@@ -241,6 +241,11 @@ void Bridge::send_message(const Iid& iid, const std::string& nick, const std::st
                              this->make_xmpp_body(body), this->user_jid, "chat");
 }
 
+void Bridge::send_join_failed(const Iid& iid, const std::string& nick, const std::string& type, const std::string& condition, const std::string& text)
+{
+  this->xmpp->send_presence_error(iid.chan + "%" + iid.server, nick, this->user_jid, type, condition, text);
+}
+
 void Bridge::send_muc_leave(Iid&& iid, std::string&& nick, const std::string& message, const bool self)
 {
   this->xmpp->send_muc_leave(std::move(iid.chan) + "%" + std::move(iid.server), std::move(nick), this->make_xmpp_body(message), this->user_jid, self);

src/bridge/bridge.hpp

@@ -80,6 +80,11 @@ public:
    * Send a MUC message from some participant
    */
   void send_message(const Iid& iid, const std::string& nick, const std::string& body, const bool muc);
+  /**
+   * Send a presence of type error, from a room. This is used to indicate
+   * why joining a room failed.
+   */
+  void send_join_failed(const Iid& iid, const std::string& nick, const std::string& type, const std::string& condition, const std::string& text);
   /**
    * Send an unavailable presence from this participant
    */

src/irc/irc_client.cpp

@@ -50,6 +50,13 @@ void IrcClient::on_connection_failed(const std::string& reason)
 {
   this->bridge->send_xmpp_message(this->hostname, "",
                                   "Connection failed: "s + reason);
+  // Send an error message for all room that the user wanted to join
+  for (const std::string& channel: this->channels_to_join)
+    {
+      Iid iid(channel + "%" + this->hostname);
+      this->bridge->send_join_failed(iid, this->current_nick,
+                                     "cancel", "item-not-found", reason);
+    }
 }
 
 void IrcClient::on_connected()
@@ -167,11 +174,11 @@ void IrcClient::send_quit_command(const std::string& reason)
 
 void IrcClient::send_join_command(const std::string& chan_name)
 {
-  this->start();
   if (this->welcomed == false)
     this->channels_to_join.push_back(chan_name);
   else
     this->send_message(IrcMessage("JOIN", {chan_name}));
+  this->start();
 }
 
 bool IrcClient::send_channel_message(const std::string& chan_name, const std::string& body)

src/xmpp/xmpp_component.cpp

@@ -796,6 +796,33 @@ void XmppComponent::send_nickname_conflict_error(const std::string& muc_name,
   this->send_stanza(presence);
 }
 
+void XmppComponent::send_presence_error(const std::string& muc_name,
+                                   const std::string& nickname,
+                                   const std::string& jid_to,
+                                   const std::string& type,
+                                   const std::string& condition,
+                                   const std::string&)
+{
+  Stanza presence("presence");
+  presence["from"] = muc_name + "@" + this->served_hostname + "/" + nickname;
+  presence["to"] = jid_to;
+  XmlNode x("x");
+  x["xmlns"] = MUC_NS;
+  x.close();
+  presence.add_child(std::move(x));
+  XmlNode error("error");
+  error["by"] = muc_name + "@" + this->served_hostname;
+  error["type"] = type;
+  XmlNode subnode(condition);
+  subnode["xmlns"] = STANZA_NS;
+  subnode.close();
+  error.add_child(std::move(subnode));
+  error.close();
+  presence.add_child(std::move(error));
+  presence.close();
+  this->send_stanza(presence);
+}
+
 void XmppComponent::send_affiliation_role_change(const std::string& muc_name,
                                                  const std::string& target,
                                                  const std::string& affiliation,

src/xmpp/xmpp_component.hpp

@@ -141,6 +141,15 @@ public:
   void send_nickname_conflict_error(const std::string& muc_name,
                                     const std::string& nickname,
                                     const std::string& jid_to);
+  /**
+   * Send a generic presence error
+   */
+  void send_presence_error(const std::string& muc_name,
+                      const std::string& nickname,
+                      const std::string& jid_to,
+                      const std::string& type,
+                      const std::string& condition,
+                      const std::string& text);
   /**
    * Send a presence from the MUC indicating a change in the role and/or
    * affiliation of a participant