degesch: start with lexically ordered chanusers

This makes nick autocompletion start in a non-arbitrary state.

NEWS

@@ -1,3 +1,8 @@
+1.3.0 (20xx-xx-xx)
+
+ * degesch: made nick autocompletion ordered by the time of last action
+
+
 1.2.0 (2021-07-08) "There Are Other Countries As Well"
 
  * degesch: added a /squery command for IRCnet

degesch.c

@@ -459,6 +459,10 @@ input_rl_start (void *input, const char *program_name)
 	rl_completer_word_break_characters = NULL;
 	rl_attempted_completion_function = app_readline_completion;
 
+	// We shouldn't produce any duplicates that the library would help us
+	// autofilter, and we don't generally want alphabetic ordering at all
+	rl_sort_completion_matches = false;
+
 	hard_assert (self->prompt != NULL);
 	// The inputrc is read before any callbacks are called, so we need to
 	// register all functions that our user may want to map up front
@@ -7266,6 +7270,19 @@ irc_handle_privmsg_text (struct server *s,
 	char *prefixes = irc_get_privmsg_prefix
 		(s, str_map_find (&s->irc_users, nickname), target);
 
+	// Make autocomplete offer the last speakers first on partial matches
+	// TODO: might want to do this on notices as well, and the behaviour
+	//   shouldn't change depending on whether CAP echo-message is enabled
+	struct user *user;
+	struct channel_user *channel_user;
+	if (buffer->channel
+	 && (user = str_map_find (&s->irc_users, nickname))
+	 && (channel_user = irc_channel_get_user (buffer->channel, user)))
+	{
+		LIST_UNLINK (buffer->channel->users, channel_user);
+		LIST_PREPEND (buffer->channel->users, channel_user);
+	}
+
 	// IRCv3.2 echo-message could otherwise cause us to highlight ourselves
 	if (irc_is_this_us (s, msg->prefix) || !irc_is_highlight (s, text->str))
 	{
@@ -7589,20 +7606,35 @@ channel_user_sort_entry_cmp (const void *entry_a, const void *entry_b)
 		b->channel_user->user->nickname);
 }
 
+static void
+irc_sort_channel_users (struct channel *channel)
+{
+	size_t n_users = channel->users_len;
+	struct channel_user_sort_entry entries[n_users], *p = entries;
+	LIST_FOR_EACH (struct channel_user, iter, channel->users)
+	{
+		p->s = channel->s;
+		p->channel_user = iter;
+		p++;
+	}
+
+	qsort (entries, n_users, sizeof *entries, channel_user_sort_entry_cmp);
+
+	channel->users = NULL;
+	while (p-- != entries)
+		LIST_PREPEND (channel->users, p->channel_user);
+}
+
 static char *
 make_channel_users_list (struct channel *channel)
 {
-	size_t n_users = 0;
-	LIST_FOR_EACH (struct channel_user, iter, channel->users)
-		n_users++;
-
-	struct channel_user_sort_entry entries[n_users];
-	size_t i = 0;
+	size_t n_users = channel->users_len;
+	struct channel_user_sort_entry entries[n_users], *p = entries;
 	LIST_FOR_EACH (struct channel_user, iter, channel->users)
 	{
-		entries[i].s = channel->s;
-		entries[i].channel_user = iter;
-		i++;
+		p->s = channel->s;
+		p->channel_user = iter;
+		p++;
 	}
 
 	qsort (entries, n_users, sizeof *entries, channel_user_sort_entry_cmp);
@@ -7610,7 +7642,7 @@ make_channel_users_list (struct channel *channel)
 	// Make names of users that are away italicised, constructing a formatter
 	// and adding a new attribute seems like unnecessary work
 	struct str list = str_make ();
-	for (i = 0; i < n_users; i++)
+	for (size_t i = 0; i < n_users; i++)
 	{
 		struct channel_user *channel_user = entries[i].channel_user;
 		if (channel_user->user->away) str_append_c (&list, '\x1d');
@@ -7663,6 +7695,9 @@ irc_process_names (struct channel *channel)
 	struct str_map present = str_map_make (NULL);
 	present.key_xfrm = channel->s->irc_strxfrm;
 
+	// Either that, or there is no other inhabitant, and sorting does nothing
+	bool we_have_just_joined = channel->users_len == 1;
+
 	struct strv *updates = &channel->names_buf;
 	for (size_t i = 0; i < updates->len; i++)
 	{
@@ -7686,6 +7721,8 @@ irc_process_names (struct channel *channel)
 	str_map_free (&present);
 	strv_reset (&channel->names_buf);
 
+	if (we_have_just_joined)
+		irc_sort_channel_users (channel);
 	if (!channel->show_names_after_who)
 		irc_process_names_finish (channel);
 }