draft/multiline: inbound BATCH parsing + concat assembly, deliver assembled lines; advertise limits

src/coremods/core_message.rs

@@ -127,9 +127,40 @@ pub fn commands() -> Vec<Box<dyn Command>> {
         Box::new(Redact),
         Box::new(MarkRead),
         Box::new(Metadata),
+        Box::new(Batch),
     ]
 }
 
+/// BATCH — the client side of draft/multiline. `BATCH +<ref> draft/multiline
+/// <target>` opens a batch; the `@batch=<ref>`-tagged PRIVMSG/NOTICE lines are
+/// buffered (see `Ircd::dispatch`); `BATCH -<ref>` assembles them (honouring
+/// `draft/multiline-concat`) and delivers each logical line normally.
+struct Batch;
+impl Command for Batch {
+    fn name(&self) -> &'static str {
+        "BATCH"
+    }
+    fn min_params(&self) -> usize {
+        1
+    }
+    fn handle(&self, s: &mut Server, uid: Uid, params: &[String]) -> CmdResult {
+        let tag = &params[0];
+        if let Some(bref) = tag.strip_prefix('+') {
+            if params.get(1).map(|t| t.as_str()) == Some("draft/multiline") {
+                let target = params.get(2).cloned().unwrap_or_default();
+                s.multiline_open(uid, bref, &target);
+            }
+        } else if let Some(bref) = tag.strip_prefix('-') {
+            if let Some((target, notice, lines)) = s.multiline_close(uid, bref) {
+                for line in lines {
+                    deliver(s, uid, &[target.clone(), line], notice);
+                }
+            }
+        }
+        CmdResult::Ok
+    }
+}
+
 /// METADATA — draft/metadata-2. `METADATA <target> <GET|LIST|SET|CLEAR> [args]`.
 /// `<target>` is `*` (self), a nick, or a `#channel`. Anyone may GET/LIST; only the
 /// user themselves or a channel op/oper may SET/CLEAR. Values are public (`*`