From b711e4983b208d3bb06c9e621b6ea5064438a6db Mon Sep 17 00:00:00 2001
From: Alex Clarke <alex.j.tusa@gmail.com>
Date: Mon, 27 Jul 2026 18:00:07 -0600
Subject: [PATCH] feat: implement ACP user-interaction to request_permission
 bridge

---
 src/acp/server.rs                | 42 +++++++++++++++++++++++++++++++-
 src/function/user_interaction.rs | 12 ++++++++-
 src/main.rs                      |  3 +++
 src/utils/mod.rs                 | 19 ++++++++++++++-
 4 files changed, 73 insertions(+), 3 deletions(-)

diff --git a/src/acp/server.rs b/src/acp/server.rs
index 5464c99..8147e4e 100644
--- a/src/acp/server.rs
+++ b/src/acp/server.rs
@@ -28,7 +28,8 @@ where
     R: tokio::io::AsyncRead + Unpin,
     W: AsyncWrite + Unpin,
 {
-    use crate::utils::create_abort_signal;
+    use crate::utils::{create_abort_signal, drain_acp_permissions};
+    drain_acp_permissions();
     let state = AcpServerState {
         ctx: None,
         abort: create_abort_signal(),
@@ -55,6 +56,9 @@ where
             continue;
         }
         if let Some(response) = dispatch(&line, &mut state).await {
+            for params in crate::utils::drain_acp_permissions() {
+                emit_notification(&mut writer, "session/request_permission", params).await?;
+            }
             emit(&mut writer, &response).await?;
         }
     }
@@ -209,6 +213,23 @@ async fn emit<W: AsyncWrite + Unpin>(writer: &mut W, response: &Response) -> Res
     Ok(())
 }
 
+async fn emit_notification<W: AsyncWrite + Unpin>(
+    writer: &mut W,
+    method: &str,
+    params: serde_json::Value,
+) -> Result<()> {
+    let frame = serde_json::json!({
+        "jsonrpc": "2.0",
+        "method": method,
+        "params": params,
+    });
+    let mut line = serde_json::to_string(&frame)?;
+    line.push('\n');
+    writer.write_all(line.as_bytes()).await?;
+    writer.flush().await?;
+    Ok(())
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -453,4 +474,23 @@ mod tests {
         assert_eq!(v["id"], 6);
         assert!(v["error"].is_object());
     }
+
+    #[tokio::test]
+    async fn emit_notification_produces_valid_json_rpc_frame() {
+        let mut output = Vec::new();
+        emit_notification(
+            &mut output,
+            "session/request_permission",
+            serde_json::json!({"action": "confirm", "question": "Proceed?"}),
+        )
+        .await
+        .unwrap();
+
+        let s = String::from_utf8(output).unwrap();
+        let v: serde_json::Value = serde_json::from_str(s.trim()).unwrap();
+        assert_eq!(v["jsonrpc"], "2.0");
+        assert_eq!(v["method"], "session/request_permission");
+        assert!(v["params"]["action"].is_string());
+        assert!(!v.as_object().unwrap().contains_key("id"));
+    }
 }
diff --git a/src/function/user_interaction.rs b/src/function/user_interaction.rs
index 7d121b2..795742e 100644
--- a/src/function/user_interaction.rs
+++ b/src/function/user_interaction.rs
@@ -1,7 +1,7 @@
 use super::{FunctionDeclaration, JsonSchema};
 use crate::config::RequestContext;
 use crate::supervisor::escalation::{EscalationRequest, new_escalation_id};
-use crate::utils::HEADLESS;
+use crate::utils::{ACP_SERVER, HEADLESS, queue_acp_permission};
 
 use anyhow::{Result, anyhow, bail};
 use indexmap::IndexMap;
@@ -138,6 +138,16 @@ pub async fn handle_user_tool(
         .strip_prefix(USER_FUNCTION_PREFIX)
         .unwrap_or(cmd_name);
 
+    if ACP_SERVER.load(Ordering::SeqCst) {
+        let result = handle_headless(action, args);
+        queue_acp_permission(json!({
+            "action": action,
+            "question": result["question"],
+            "options": result["options"],
+        }));
+        return Ok(result);
+    }
+
     if HEADLESS.load(Ordering::SeqCst) {
         return Ok(handle_headless(action, args));
     }
diff --git a/src/main.rs b/src/main.rs
index 995c7ba..3755850 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -91,6 +91,9 @@ async fn main() -> Result<()> {
             env::set_var("AUTO_CONFIRM", "true");
         }
         HEADLESS.store(true, Ordering::SeqCst);
+        if cli.acp_server {
+            ACP_SERVER.store(true, Ordering::SeqCst);
+        }
     }
 
     let info_flag = cli.info
diff --git a/src/utils/mod.rs b/src/utils/mod.rs
index 7779c93..6297ae7 100644
--- a/src/utils/mod.rs
+++ b/src/utils/mod.rs
@@ -33,8 +33,9 @@ use fuzzy_matcher::{FuzzyMatcher, skim::SkimMatcherV2};
 use is_terminal::IsTerminal;
 use nu_ansi_term::Color;
 use std::borrow::Cow;
+use std::collections::VecDeque;
 use std::sync::atomic::AtomicBool;
-use std::sync::{LazyLock, OnceLock};
+use std::sync::{LazyLock, Mutex, OnceLock};
 use std::{cmp, env, path::PathBuf, process};
 use syntect::highlighting::{Highlighter, Theme};
 use syntect::parsing::Scope;
@@ -45,6 +46,22 @@ pub static THINK_TAG_RE: LazyLock<Regex> =
     LazyLock::new(|| Regex::new(r"(?s)^\s*<think>.*?</think>(\s*|$)").unwrap());
 pub static IS_STDOUT_TERMINAL: LazyLock<bool> = LazyLock::new(|| std::io::stdout().is_terminal());
 pub static HEADLESS: AtomicBool = AtomicBool::new(false);
+pub static ACP_SERVER: AtomicBool = AtomicBool::new(false);
+
+static ACP_PERMISSION_QUEUE: Mutex<VecDeque<serde_json::Value>> = Mutex::new(VecDeque::new());
+
+pub fn queue_acp_permission(notification: serde_json::Value) {
+    if let Ok(mut q) = ACP_PERMISSION_QUEUE.lock() {
+        q.push_back(notification);
+    }
+}
+
+pub fn drain_acp_permissions() -> Vec<serde_json::Value> {
+    ACP_PERMISSION_QUEUE
+        .lock()
+        .map(|mut q| q.drain(..).collect())
+        .unwrap_or_default()
+}
 pub static NO_COLOR: LazyLock<bool> = LazyLock::new(|| {
     env::var("NO_COLOR")
         .ok()