Messages to room participants are forwarded to the IRC user

For example, both JID #chan%server@biboumi/Toto and toto!server@biboumi are
equivalent, except that if you send a message to the first one, subsequent
messages coming from the user toto will come from that same JID. This is
done to be consistent for the XMPP user, and respond from the same JID than
the 'to' of the first message.

fix #2468

src/bridge/bridge.cpp

@@ -242,8 +242,18 @@ void Bridge::send_message(const Iid& iid, const std::string& nick, const std::st
     this->xmpp->send_muc_message(std::to_string(iid), nick,
                                  this->make_xmpp_body(body), this->user_jid);
   else
-    this->xmpp->send_message(std::to_string(iid),
+    {
-                             this->make_xmpp_body(body), this->user_jid, "chat");
+      std::string target = std::to_string(iid);
+      bool fulljid = false;
+      auto it = this->preferred_user_from.find(iid.get_local());
+      if (it != this->preferred_user_from.end())
+        {
+          target = it->second;
+          fulljid = true;
+        }
+      this->xmpp->send_message(target, this->make_xmpp_body(body),
+                               this->user_jid, "chat", fulljid);
+    }
 }
 
 void Bridge::send_join_failed(const Iid& iid, const std::string& nick, const std::string& type, const std::string& condition, const std::string& text)
@@ -343,3 +353,19 @@ void Bridge::send_iq_version_request(const std::string& nick, const std::string&
 {
   this->xmpp->send_iq_version_request(nick + "!" + hostname, this->user_jid);
 }
+
+void Bridge::set_preferred_from_jid(const std::string& nick, const std::string& full_jid)
+{
+  auto it = this->preferred_user_from.find(nick);
+  if (it == this->preferred_user_from.end())
+    this->preferred_user_from.emplace(nick, full_jid);
+  else
+    this->preferred_user_from[nick] = full_jid;
+}
+
+void Bridge::remove_preferred_from_jid(const std::string& nick)
+{
+  auto it = this->preferred_user_from.find(nick);
+  if (it != this->preferred_user_from.end())
+    this->preferred_user_from.erase(it);
+}

src/bridge/bridge.hpp

@@ -123,6 +123,14 @@ public:
    * Get the number of server to which this bridge is connected or connecting.
    */
   size_t active_clients() const;
+  /**
+   * Add (or replace the existing) <nick, jid> into the preferred_user_from map
+   */
+  void set_preferred_from_jid(const std::string& nick, const std::string& full_jid);
+  /**
+   * Remove the preferred jid for the given IRC nick
+   */
+  void remove_preferred_from_jid(const std::string& nick);
 
 private:
   /**
@@ -157,6 +165,14 @@ private:
    * their sockets.
    */
   std::shared_ptr<Poller> poller;
+  /**
+   * A map of <nick, full_jid>. For example if this map contains <"toto",
+   * "#somechan%server@biboumi/ToTo">, whenever a private message is
+   * received from the user "toto", instead of forwarding it to XMPP with
+   * from='toto!server@biboumi', we use instead
+   * from='#somechan%server@biboumi/ToTo'
+   */
+  std::unordered_map<std::string, std::string> preferred_user_from;
 
   Bridge(const Bridge&) = delete;
   Bridge(Bridge&& other) = delete;

src/xmpp/xmpp_component.cpp

@@ -1,4 +1,5 @@
 #include <utils/scopeguard.hpp>
+#include <utils/tolower.hpp>
 #include <logger/logger.hpp>
 
 #include <xmpp/xmpp_component.hpp>
@@ -355,9 +356,10 @@ void XmppComponent::handle_message(const Stanza& stanza)
   XmlNode* body = stanza.get_child("body", COMPONENT_NS);
   if (type == "groupchat" && iid.is_channel)
     {
-      if (to.resource.empty())
       if (body && !body->get_inner().empty())
+        {
           bridge->send_channel_message(iid, body->get_inner());
+        }
       XmlNode* subject = stanza.get_child("subject", COMPONENT_NS);
       if (subject)
         bridge->set_channel_topic(iid, subject->get_inner());
@@ -379,10 +381,25 @@ void XmppComponent::handle_message(const Stanza& stanza)
       if (kickable_error)
         bridge->shutdown("Error from remote client");
     }
-  else if (type == "chat" && iid.is_user && !iid.get_local().empty())
+  else if (type == "chat")
     {
       if (body && !body->get_inner().empty())
+        {
+          // a message for nick!server
+          if (iid.is_user && !iid.get_local().empty())
+            {
               bridge->send_private_message(iid, body->get_inner());
+              bridge->remove_preferred_from_jid(iid.get_local());
+            }
+          else if (!iid.is_user && !to.resource.empty())
+            { // a message for chan%server@biboumi/Nick or
+              // server@biboumi/Nick
+              // Convert that into a message to nick!server
+              Iid user_iid(utils::tolower(to.resource) + "!" + iid.get_server());
+              bridge->send_private_message(user_iid, body->get_inner());
+              bridge->set_preferred_from_jid(user_iid.get_local(), to_str);
+            }
+        }
     }
   else if (iid.is_user)
     this->send_invalid_user_error(to.local, from);
@@ -571,10 +588,13 @@ void* XmppComponent::get_receive_buffer(const size_t size) const
   return this->parser.get_buffer(size);
 }
 
-void XmppComponent::send_message(const std::string& from, Xmpp::body&& body, const std::string& to, const std::string& type)
+void XmppComponent::send_message(const std::string& from, Xmpp::body&& body, const std::string& to, const std::string& type, const bool fulljid)
 {
   XmlNode node("message");
   node["to"] = to;
+  if (fulljid)
+    node["from"] = from;
+  else
     node["from"] = from + "@" + this->served_hostname;
   if (!type.empty())
     node["type"] = type;

src/xmpp/xmpp_component.hpp

@@ -111,9 +111,13 @@ public:
   void close_document();
   /**
    * Send a message from from@served_hostname, with the given body
+   *
+   * If fulljid is false, the provided 'from' doesn't contain the
+   * server-part of the JID and must be added.
    */
   void send_message(const std::string& from, Xmpp::body&& body,
-                    const std::string& to, const std::string& type);
+                    const std::string& to, const std::string& type,
+                    const bool fulljid=false);
   /**
    * Send a join from a new participant
    */