Add InfoServ, unifying network bulletins onto the news store

InfoServ becomes the dedicated home for network information bulletins,
backed by the same event-sourced news store OperServ NEWS used — one place
to post, not two. POST/LIST/DEL manage public bulletins (shown to every
user on connect); OPOST/OLIST/ODEL the oper ones (shown to operators on
login). Anyone may LIST the public bulletins; posting/removing is admin-
only. The engine's existing connect/login display hooks render them
unchanged. The OperServ NEWS command is retired accordingly (the news
events and the display path stay). Default service.

infoserv/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "fedserv-infoserv"
+version = "0.0.1"
+edition = "2021"
+description = "InfoServ: network information bulletins shown on connect (public) and on oper login."
+
+[dependencies]
+fedserv-api = { path = "../api" }

infoserv/src/lib.rs

@@ -0,0 +1,103 @@
+//! InfoServ manages the network information bulletins. Public bulletins are
+//! shown to every user as they connect; oper bulletins are shown to operators
+//! when they log in (both are displayed by the engine — the same hooks OperServ
+//! once drove through its NEWS command). This is the dedicated front-end over
+//! that one shared news store, so there aren't two ways to post the same thing.
+//!
+//! POST/LIST/DEL manage public bulletins; OPOST/OLIST/ODEL the oper ones.
+//! Posting and deleting are admin-only; anyone may LIST the public bulletins,
+//! and any operator may OLIST.
+
+use fedserv_api::{NetView, Priv, Sender, Service, ServiceCtx, Store};
+
+// The two bulletin kinds in the shared news store.
+const PUBLIC: &str = "logon";
+const OPER: &str = "oper";
+
+pub struct InfoServ {
+    pub uid: String,
+}
+
+impl Service for InfoServ {
+    fn nick(&self) -> &str {
+        "InfoServ"
+    }
+    fn uid(&self) -> &str {
+        &self.uid
+    }
+    fn gecos(&self) -> &str {
+        "Information Service"
+    }
+
+    fn on_command(&mut self, from: &Sender, args: &[&str], ctx: &mut ServiceCtx, _net: &dyn NetView, db: &mut dyn Store) {
+        let me = self.uid.as_str();
+        match args.first().map(|s| s.to_ascii_uppercase()).as_deref() {
+            Some("POST") | Some("ADD") => post(me, from, PUBLIC, &args[1..], ctx, db),
+            Some("OPOST") | Some("OADD") => post(me, from, OPER, &args[1..], ctx, db),
+            Some("DEL") | Some("REMOVE") => del(me, from, PUBLIC, args.get(1).copied(), ctx, db),
+            Some("ODEL") => del(me, from, OPER, args.get(1).copied(), ctx, db),
+            // Public bulletins are, well, public — anyone may list them.
+            Some("LIST") | None => list(me, from, PUBLIC, false, ctx, db),
+            // Oper bulletins are for operators only.
+            Some("OLIST") => list(me, from, OPER, true, ctx, db),
+            Some("HELP") => help(me, from, ctx),
+            Some(other) => ctx.notice(me, from.uid, format!("I don't know \x02{other}\x02. Try \x02LIST\x02 or \x02HELP\x02.")),
+        }
+    }
+}
+
+fn help(me: &str, from: &Sender, ctx: &mut ServiceCtx) {
+    ctx.notice(me, from.uid, "InfoServ holds the network's information bulletins. \x02LIST\x02 shows the public ones. Operators: \x02POST\x02 <message> / \x02DEL\x02 <number> (public, shown on connect), \x02OPOST\x02 / \x02OLIST\x02 / \x02ODEL\x02 (oper-only, shown on login).");
+}
+
+fn post(me: &str, from: &Sender, kind: &str, rest: &[&str], ctx: &mut ServiceCtx, db: &mut dyn Store) {
+    if !from.privs.has(Priv::Admin) {
+        ctx.notice(me, from.uid, "Access denied — posting bulletins is for services operators.");
+        return;
+    }
+    let message = rest.join(" ");
+    if message.trim().is_empty() {
+        ctx.notice(me, from.uid, format!("Syntax: {} <message>", if kind == OPER { "OPOST" } else { "POST" }));
+        return;
+    }
+    let setter = from.account.unwrap_or(from.nick);
+    db.news_add(kind, &message, setter);
+    let which = if kind == OPER { "oper" } else { "public" };
+    ctx.notice(me, from.uid, format!("Added a \x02{which}\x02 bulletin."));
+}
+
+fn del(me: &str, from: &Sender, kind: &str, num: Option<&str>, ctx: &mut ServiceCtx, db: &mut dyn Store) {
+    if !from.privs.has(Priv::Admin) {
+        ctx.notice(me, from.uid, "Access denied — that command is for services operators.");
+        return;
+    }
+    let which = if kind == OPER { "oper" } else { "public" };
+    let Some(n) = num.and_then(|n| n.parse::<usize>().ok()) else {
+        ctx.notice(me, from.uid, format!("Syntax: {} <number>", if kind == OPER { "ODEL" } else { "DEL" }));
+        return;
+    };
+    match db.news(kind).get(n.wrapping_sub(1)) {
+        Some(item) if n >= 1 => {
+            db.news_del(item.id);
+            ctx.notice(me, from.uid, format!("Removed \x02{which}\x02 bulletin \x02{n}\x02."));
+        }
+        _ => ctx.notice(me, from.uid, format!("There's no \x02{which}\x02 bulletin \x02{n}\x02.")),
+    }
+}
+
+fn list(me: &str, from: &Sender, kind: &str, oper_only: bool, ctx: &mut ServiceCtx, db: &mut dyn Store) {
+    if oper_only && !from.privs.any() {
+        ctx.notice(me, from.uid, "Access denied — oper bulletins are for services operators.");
+        return;
+    }
+    let items = db.news(kind);
+    let which = if kind == OPER { "oper" } else { "public" };
+    if items.is_empty() {
+        ctx.notice(me, from.uid, format!("There are no {which} bulletins."));
+        return;
+    }
+    for (i, item) in items.iter().enumerate() {
+        ctx.notice(me, from.uid, format!("{}. {} — by {}", i + 1, item.text, item.setter));
+    }
+    ctx.notice(me, from.uid, format!("End of {which} bulletins ({} shown).", items.len()));
+}