From 04ad9c6ed77952ef4e70c8a72a313870450e0515 Mon Sep 17 00:00:00 2001
From: tali <iitalics@gmail.com>
Date: Wed, 24 Jan 2024 12:10:33 -0500
Subject: [PATCH] cover some edge cases such as join a channel twice

---
 lib/server/connection.ml | 84 +++++++++++++++++++---------------------
 1 file changed, 40 insertions(+), 44 deletions(-)

diff --git a/lib/server/connection.ml b/lib/server/connection.ml
index 87863fb..38c925d 100644
--- a/lib/server/connection.ml
+++ b/lib/server/connection.ml
@@ -261,21 +261,16 @@ let on_msg_names t name =
   Ok ()
 
 let join t user chan =
-  begin
-    (* TODO: check if already a member *)
-    (* TODO: check channel mode +k, +l *)
-    let msg = Msg.make "JOIN" [Chan.name chan] in
-    Router.relay msg ~from:user [`to_chan chan; `to_self];
-
-    Router.join chan user;
-
-    if not (Chan.is_registered chan ~router:t.router) then
-      begin
-        (* TODO: make founder +o / +q etc. *)
-        Chan.register chan ~router:t.router;
-        set_chan_mode chan ~from:user ~add:t.server_info.conf.init_cmode;
-      end
-  end
+  (* TODO: check channel mode +k, +l *)
+  let msg = Msg.make "JOIN" [Chan.name chan] in
+  Router.relay msg ~from:user [`to_chan chan; `to_self];
+  Router.join chan user;
+  if not (Chan.is_registered chan ~router:t.router) then
+    begin
+      (* TODO: make founder +o / +q etc. *)
+      Chan.register chan ~router:t.router;
+      set_chan_mode chan ~from:user ~add:t.server_info.conf.init_cmode;
+    end
 
 let on_msg_join t name =
   let* me = require_registered t in
@@ -290,34 +285,35 @@ let on_msg_join t name =
       debug (fun m -> m "making new channel %S" name);
       Ok (Chan.make ~name)
   in
-  join t me chan;
-  (* TODO: send channel topic *)
-  list_names t chan;
-  Ok ()
+  match Router.membership chan me with
+  | _already_a_member ->
+    Ok ()
+  | exception Not_found ->
+    join t me chan;
+    (* TODO: send channel topic *)
+    list_names t chan;
+    Ok ()
 
-let part t user chan ~reason =
+let leave t user chan ~why =
   let mem = Router.membership chan user in
-  begin
-    (* edge case: don't relay PART messages if the user is QUIT'ing *)
-    (* FIXME: this will need to be changed again to handle KICK, i think *)
-    if User.is_registered user ~router:t.router then
-      begin
-        let always_trailing = Option.is_some reason in
-        let reason = Option.to_list reason in
-        let msg = Msg.make "PART" (Chan.name chan :: reason) ~always_trailing in
-        Router.relay msg ~from:user [`to_chan chan; `to_self];
-      end;
-
-    Router.part mem;
-
-    (* TODO: if user was op then choose a new op? *)
-
-    if Chan.no_members chan then
-      begin
-        debug (fun m -> m "recycling empty channel %S" (Chan.name chan));
-        Chan.unregister chan ~router:t.router;
-      end
-  end
+  begin match why with
+    (* TODO: KICK *)
+    | `quit ->
+      (* if called from [quit], then we already relayed the QUIT message *)
+      ()
+    | `part reason ->
+      let always_trailing = Option.is_some reason in
+      let reason = Option.to_list reason in
+      let msg = Msg.make "PART" (Chan.name chan :: reason) ~always_trailing in
+      Router.relay msg ~from:user [`to_chan chan; `to_self]
+  end;
+  Router.part mem;
+  (* TODO: if user was op then choose a new op? *)
+  if Chan.no_members chan then
+    begin
+      debug (fun m -> m "recycling empty channel %S" (Chan.name chan));
+      Chan.unregister chan ~router:t.router;
+    end
 
 let on_msg_part t name reason =
   let reason = match reason with
@@ -334,7 +330,7 @@ let on_msg_part t name reason =
       Error (nosuchchannel name)
   in
   try
-    part t me chan ~reason;
+    leave t me chan ~why:(`part reason);
     Ok ()
   with Not_found ->
     Error (notonchannel name)
@@ -380,11 +376,11 @@ let quit t me ~reason =
     let msg = Msg.make "QUIT" [User.nick me; reason] ~always_trailing:true in
     Router.relay msg ~from:me [`to_interested];
 
-    User.unregister me ~router:t.router;
     List.iter
-      (part t me ~reason:None)
+      (leave t me ~why:`quit)
       (User.channels me);
 
+    User.unregister me ~router:t.router;
     t.user <- None
   end