Honor userhost-in-names and account-tag caps end-to-end

NAMES (RPL_NAMREPLY) now appends nick!user@host when the requesting
client has negotiated userhost-in-names, both on JOIN and on the
explicit NAMES command.

account-tag is now applied even for unauthenticated senders: per
the IRCv3 spec, the value is the literal '*' when no account is
known. Previously we silently dropped the tag, which made the
ACK meaningless for anonymous clients.

1 files changed, 38 insertions, 35 deletions

diff --git a/src/papod.clj b/src/papod.clj
index e20bec8..d5b6f20 100644
--- a/src/papod.clj
+++ b/src/papod.clj
@@ -1072,6 +1072,7 @@
 (declare ban-matches?)
 (declare mute-matches?)
 (declare mute-except-matches?)
+(declare nuh-for-nick)
 
 (defn- persistent-channels
   "Channel handles where `nick` has stored membership."
@@ -2421,30 +2422,25 @@
                                           (str k "=" v))
                                         client-tag-pairs)))
                   sender-acct (:account @client)
-                  acct-tag (when sender-acct
-                             (str "account=" sender-acct))
+                  acct-tag (str "account=" (or sender-acct "*"))
                   delivery-target (or raw-target target)
                   raw      (str ":" nick " PRIVMSG "
                                 delivery-target " " content)
                   tagged   (tag-line-at msg-id msg-at out-tags
                              raw)
-                  tagged-acct (when acct-tag
-                                (tag-line-at msg-id msg-at
-                                  (conj out-tags acct-tag)
-                                  raw))
+                  tagged-acct (tag-line-at msg-id msg-at
+                                (conj out-tags acct-tag)
+                                raw)
                   ;; server-time only: msgid + time, no
                   ;; forwarded client-only tags
                   time-only (tag-line-at msg-id msg-at [] raw)
-                  time-only-acct (when acct-tag
-                                   (tag-line-at msg-id msg-at
-                                     [acct-tag] raw))
+                  time-only-acct (tag-line-at msg-id msg-at
+                                   [acct-tag] raw)
                   pick-line
                   (fn [caps]
                     (let [mt? (and caps (caps "message-tags"))
                           st? (and caps (caps "server-time"))
-                          at? (and acct-tag
-                                   caps
-                                   (caps "account-tag"))]
+                          at? (and caps (caps "account-tag"))]
                       (cond
                         mt? (if at? tagged-acct tagged)
                         st? (if at? time-only-acct time-only)
@@ -2516,7 +2512,7 @@
     (contains? (get @ops handle) nick)))
 
 (defn- names-for
-  [components handle & {:keys [multi-prefix?]}]
+  [components handle & {:keys [multi-prefix? userhost?]}]
   (let [members (when (:channels components)
                   (get @(:channels components) handle))
         ops     (:ops components)
@@ -2525,19 +2521,22 @@
       (string/join
        " "
        (map (fn [mn]
-              (let [op?  (and ops
-                              (contains?
-                               (get @ops handle) mn))
-                    voc? (and voiced
-                              (contains?
-                               (get @voiced handle)
-                               mn))]
+              (let [op?   (and ops
+                               (contains?
+                                (get @ops handle) mn))
+                    voc?  (and voiced
+                               (contains?
+                                (get @voiced handle)
+                                mn))
+                    body  (if userhost?
+                            (nuh-for-nick components mn)
+                            mn)]
                 (cond
                   (and op? voc? multi-prefix?)
-                  (str "@+" mn)
-                  op?  (str "@" mn)
-                  voc? (str "+" mn)
-                  :else mn)))
+                  (str "@+" body)
+                  op?  (str "@" body)
+                  voc? (str "+" body)
+                  :else body)))
             members)))))
 
 (defn- chan-modes-for
@@ -2885,8 +2884,11 @@
               ;; Build replies for the joining client
               (let [mp?     (contains? my-caps
                               "multi-prefix")
+                    uh?     (contains? my-caps
+                              "userhost-in-names")
                     members (names-for components handle
-                             :multi-prefix? mp?)
+                             :multi-prefix? mp?
+                             :userhost?     uh?)
                     sym     (chan-symbol components handle)
                     db'     (when conn (d/db conn))
                     ch-eid' (when db'
@@ -6013,10 +6015,9 @@
               (let [base
                     (str ":" (client-prefix client)
                          " INVITE " p1 " " p2)
-                    acct (:account @client)
+                    acct (or (:account @client) "*")
                     tagged-base
-                    (when acct
-                      (str "@account=" acct " " base))
+                    (str "@account=" acct " " base)
                     inviting (numeric-reply client "341"
                                (str target " " handle))]
                 (when-let [m (and clients
@@ -6024,8 +6025,7 @@
                   (let [ca   (:client-atom m)
                         caps (when ca
                                (or (:caps @ca) #{}))
-                        line (if (and tagged-base
-                                      (caps "account-tag"))
+                        line (if (caps "account-tag")
                                tagged-base
                                base)]
                     (deliver-to-client! (:w m) line)))
@@ -6048,8 +6048,7 @@
                             :when (and m
                                        (caps "invite-notify"))]
                       (deliver-to-client! (:w m)
-                        (if (and tagged-base
-                                 (caps "account-tag"))
+                        (if (caps "account-tag")
                           tagged-base base)))))
                 ;; When the channel does not exist, also
                 ;; echo the INVITE back to the inviter
@@ -6130,9 +6129,12 @@
                              ":End of /LIST")))
           "NAMES"       (let [raw-arg (first params)
                               chans   (:channels components)
+                              caps0   (or (:caps @client) #{})
                               mp?     (contains?
-                                       (or (:caps @client) #{})
-                                       "multi-prefix")
+                                       caps0 "multi-prefix")
+                              uh?     (contains?
+                                       caps0
+                                       "userhost-in-names")
                               one-chan
                               (fn [ch]
                                 (let [present?
@@ -6142,7 +6144,8 @@
                                       (when present?
                                         (names-for
                                           components ch
-                                          :multi-prefix? mp?))
+                                          :multi-prefix? mp?
+                                          :userhost?     uh?))
                                       sym (chan-symbol
                                             components ch)]
                                   (cond->