Implement USERHOST

sable_ircd/src/command/handlers/userhost.rs

@@ -0,0 +1,45 @@
+use super::*;
+use itertools::Itertools;
+
+/// "The USERHOST command takes up to five nicknames, each a separate parameters."
+/// -- https://modern.ircdocs.horse/#userhost-message
+const MAX_TARGETS: usize = 5;
+
+fn away_char(user: &wrapper::User) -> char {
+    if user.away_reason().is_some() {
+        '-'
+    } else {
+        '+'
+    }
+}
+
+#[command_handler("USERHOST")]
+/// Syntax: USERHOST <nickname>{ <nickname>}
+fn userhost_handler(
+    response: &dyn CommandResponse,
+    network: &Network,
+    args: ArgList,
+) -> CommandResult {
+    if args.is_empty() {
+        Err(CommandError::NotEnoughParameters)
+    } else {
+        let reply = args
+            .iter()
+            .take(MAX_TARGETS)
+            .flat_map(Nickname::convert)
+            .flat_map(|nick| network.user_by_nick(&nick))
+            .map(|user| {
+                format!(
+                    "{}={}{}@{}",
+                    user.nick(),
+                    away_char(&user),
+                    user.user(),
+                    user.visible_host()
+                )
+            })
+            .join(" ");
+
+        response.numeric(make_numeric!(Userhost, &reply));
+        Ok(())
+    }
+}

sable_ircd/src/command/mod.rs

@@ -62,6 +62,7 @@ mod handlers {
     mod rename;
     mod topic;
     mod user;
+    mod userhost;
     mod who;
     mod whois;
 

sable_ircd/src/command/plumbing/argument_list.rs

@@ -14,8 +14,12 @@ impl<'a> ArgListIter<'a> {
     pub fn peek(&self) -> Option<&'a str> {
         self.list.get(self.index).map(AsRef::as_ref)
     }
+}
+
+impl<'a> Iterator for ArgListIter<'a> {
+    type Item = &'a str;
 
-    pub fn next(&mut self) -> Option<&'a str> {
+    fn next(&mut self) -> Option<&'a str> {
         let idx = self.index;
         self.index += 1;
         self.list.get(idx).map(AsRef::as_ref)

sable_ircd/src/messages/numeric.rs

@@ -12,6 +12,7 @@ define_messages! {
 
     221(UserModeIs)             => { (modestring: &str)         => ":{modestring}" },
     301(Away)                   => { (nick: &User.nick(), reason: &AwayReason)  => "{nick} :{reason}" },
+    302(Userhost)               => { (reply: &str)              => ":{reply}" },
     305(Unaway)                 => { ()                         => ":You are no longer marked as being away" },
     306(NowAway)                => { ()                         => ":You have been marked as being away" },
     311(WhoisUser)              => { (nick: &User.nick(), user=nick.user(), host=nick.visible_host(), realname=nick.realname())