From 43a4a4f4d2f7f36acdbe9c838fb4ad137a08cbc9 Mon Sep 17 00:00:00 2001
From: Condorra <kvox990h@anonaddy.me>
Date: Sun, 17 Nov 2024 11:59:13 +1100
Subject: [PATCH] Basic TERMTYPE implementation.

---
 src/lua_engine.rs             |  3 +-
 src/lua_engine/muds.rs        | 69 +++++++++++++++++++++++++++++++++--
 src/lua_engine/muds/telopt.rs |  9 ++++-
 3 files changed, 75 insertions(+), 6 deletions(-)

diff --git a/src/lua_engine.rs b/src/lua_engine.rs
index b680dab..575e335 100644
--- a/src/lua_engine.rs
+++ b/src/lua_engine.rs
@@ -311,7 +311,8 @@ pub fn install_lua_globals(
             register_class_function!(mud_class_table, mudoutput_wont);
             register_class_function!(mud_class_table, mudoutput_do);
             register_class_function!(mud_class_table, mudoutput_dont);
-            register_class_function!(mud_class_table, mudoutput_subnegotiation);
+            register_stateless_class_function!(mud_class_table, mudoutput_subnegotiation);
+            register_class_function!(mud_class_table, mudoutput_subnegotiation_termtype);
             register_class_function!(mud_class_table, mudinput_line);
             register_class_function!(mud_class_table, "closed", mudclass_closed);
             register_stateless_class_function!(mud_class_table, "new", new_mud);
diff --git a/src/lua_engine/muds.rs b/src/lua_engine/muds.rs
index 3e42c36..f8fde26 100644
--- a/src/lua_engine/muds.rs
+++ b/src/lua_engine/muds.rs
@@ -4,6 +4,7 @@ use piccolo::{
     self, async_sequence, Callback, CallbackReturn, Context, FromValue, Function, IntoValue,
     SequenceReturn, StashedTable, StashedUserData, StashedValue, Table, UserData, Value,
 };
+use telopt::TERMTYPE_TELOPT;
 use wasm_bindgen::JsValue;
 use web_sys::{console, window};
 use yew::UseStateSetter;
@@ -239,6 +240,7 @@ pub(super) fn connect_mud<'gc>(
         if naws {
             set_option_supported(ctx, &conntab, &NAWS_TELOPT, &Side::Us);
         }
+        set_option_supported(ctx, &conntab, &TERMTYPE_TELOPT, &Side::Us);
 
         // Call conntab:new...
         let seq = async_sequence(&ctx, |locals, mut seq| {
@@ -596,11 +598,72 @@ pub(super) fn mudoutput_dont<'gc>(
         Ok(CallbackReturn::Return)
     })
 }
-pub(super) fn mudoutput_subnegotiation<'gc>(
+pub(super) fn mudoutput_subnegotiation<'gc>(ctx: Context<'gc>) -> Callback<'gc> {
+    Callback::from_fn(&ctx, move |ctx, _ex, mut stack| {
+        let (mud, mut msg): (Table, Vec<u8>) = stack.consume(ctx)?;
+        if msg.is_empty() {
+            console::log_1(&JsValue::from_str(
+                "Received invalid subnegotiation with no type",
+            ));
+            return Ok(CallbackReturn::Return);
+        }
+        let msg_type = msg.remove(0);
+        let msg_typename = name_telopt(ctx, msg_type)?;
+
+        let seq = async_sequence(&ctx, |locals, mut seq| {
+            let mud = locals.stash(&ctx, mud);
+            let msg = locals.stash(&ctx, msg.into_value(ctx));
+            async move {
+                call_checking_metatable(
+                    &mut seq,
+                    mud,
+                    format!("mudoutput_subnegotiation_{}", &msg_typename),
+                    &[msg],
+                )
+                .await?;
+                Ok(SequenceReturn::Return)
+            }
+        });
+
+        Ok(CallbackReturn::Sequence(seq))
+    })
+}
+
+pub(super) fn mudoutput_subnegotiation_termtype<'gc>(
     ctx: Context<'gc>,
-    _global_memo: &GlobalMemoCell,
+    global_memo: &GlobalMemoCell,
 ) -> Callback<'gc> {
-    Callback::from_fn(&ctx, move |_ctx, _ex, _stack| Ok(CallbackReturn::Return))
+    let global_memo = global_memo.clone();
+    Callback::from_fn(&ctx, move |ctx, _ex, mut stack| {
+        let (mud, mut msg): (Table, Vec<u8>) = stack.consume(ctx)?;
+        if msg.is_empty() {
+            return Ok(CallbackReturn::Return);
+        }
+        let cmd = msg.remove(0);
+
+        let socket: Value = mud.get(ctx, "socket")?;
+        let socket: &WebSocketId =
+            UserData::from_value(ctx, socket)?.downcast::<Rootable![Gc<'_, WebSocketId>]>()?;
+
+        const SEND_CMD: u8 = 1;
+        match cmd {
+            SEND_CMD => {
+                send_subnegotiation_if_allowed(
+                    ctx,
+                    &mud,
+                    &TERMTYPE_TELOPT,
+                    &Side::Us,
+                    &mut MudWithMemo {
+                        memo: global_memo.clone(),
+                        mud: socket.clone(),
+                    },
+                    format!("\x00{}", "xterm").as_bytes(),
+                );
+                Ok(CallbackReturn::Return)
+            }
+            _ => Ok(CallbackReturn::Return),
+        }
+    })
 }
 
 pub(super) fn mudinput_line<'gc>(
diff --git a/src/lua_engine/muds/telopt.rs b/src/lua_engine/muds/telopt.rs
index 93cd112..bf70dff 100644
--- a/src/lua_engine/muds/telopt.rs
+++ b/src/lua_engine/muds/telopt.rs
@@ -193,6 +193,7 @@ pub fn send_subnegotiation_if_allowed<'gc, T: SendRaw>(
     if get_option_state(ctx, mud_table, opt, side) == OptionState::Yes {
         let mut buf: Vec<u8> = Vec::with_capacity(msg.len() + 4);
         buf.extend_from_slice(&[IAC, STARTSUB]);
+        buf.push(opt.0);
         for c in msg {
             if *c == IAC {
                 buf.extend_from_slice(b"\xff\xff");
@@ -426,8 +427,9 @@ pub fn handle_incoming_dont<'gc, T: SendOptNeg>(
     );
 }
 
-pub const GMCP_TELOPT: Telopt = Telopt(201);
+pub const TERMTYPE_TELOPT: Telopt = Telopt(24);
 pub const NAWS_TELOPT: Telopt = Telopt(31);
+pub const GMCP_TELOPT: Telopt = Telopt(201);
 
 fn negotiate_option_on<'gc, T: SendOptNeg>(
     ctx: Context<'gc>,
@@ -522,7 +524,10 @@ pub fn configure_telopt_table<'gc>(ctx: Context<'gc>, table: &Table<'gc>) {
         .set(ctx, "naws", NAWS_TELOPT.0)
         .expect("Can't set NAWS in telopt table");
     table
-        .set(ctx, "gmcp", GMCP_TELOPT.0)
+        .set(ctx, "naws", NAWS_TELOPT.0)
+        .expect("Can't set NAWS in telopt table");
+    table
+        .set(ctx, "termtype", TERMTYPE_TELOPT.0)
         .expect("Can't set GMCP in telopt table");
 }