Add documentation to treetest

2026-06-08 22:38:01 -06:00 · 2026-04-22 10:25:03 -06:00
parent 1af134104e
commit cd301dea67
14 changed files with 2216 additions and 769 deletions
@@ -193,6 +193,12 @@ dependencies = [
 "log",
 ]
 [[package]]
 name = "equivalent"
 version = "1.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "877a4ace8713b0bcf2a4e7eec82529c029f1d0619886d18145fea96c3ffe5c0f"
 [[package]]
 name = "funty"
 version = "2.0.0"
@@ -210,6 +216,12 @@ dependencies = [
 "wasi",
 ]
 [[package]]
 name = "glob"
 version = "0.3.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0cc23270f6e1808e30a928bdc84dea0b9b4136a8bc82338574f23baf47bbd280"
 [[package]]
 name = "hashbrown"
 version = "0.12.3"
@@ -219,18 +231,40 @@ dependencies = [
 "ahash",
 ]
 [[package]]
 name = "hashbrown"
 version = "0.17.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4f467dd6dccf739c208452f8014c75c18bb8301b050ad1cfb27153803edb0f51"
 [[package]]
 name = "heck"
 version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2304e00983f87ffb38b55b444b5e3b60a884b5d30c0fca7d82fe33449bbe55ea"
 [[package]]
 name = "indexmap"
 version = "2.14.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d466e9454f08e4a911e14806c24e16fba1b4c121d1ea474396f396069cf949d9"
 dependencies = [
 "equivalent",
 "hashbrown 0.17.0",
 ]
 [[package]]
 name = "is_terminal_polyfill"
 version = "1.70.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a6cb138bb79a146c1bd460005623e142ef0181e3d0219cb493e02f7d08a35695"
 [[package]]
 name = "itoa"
 version = "1.0.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8f42a60cbdf9a97f5d2305f08a87dc4e09308d1276d28c869c684d7777685682"
 [[package]]
 name = "jiff"
 version = "0.2.23"
@@ -401,7 +435,7 @@ dependencies = [
 "bitvec",
 "bytecheck",
 "bytes",
- "hashbrown",
+ "hashbrown 0.12.3",
 "ptr_meta",
 "rend",
 "rkyv_derive",
@@ -433,6 +467,15 @@ version = "4.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1c107b6f4780854c8b126e228ea8869f4d7b71260f962fefb57b996b8959ba6b"
 [[package]]
 name = "serde"
 version = "1.0.228"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9a8e94ea7f378bd32cbbd37198a4a91436180c5bb472411e48b5ec2e2124ae9e"
 dependencies = [
 "serde_core",
 ]
 [[package]]
 name = "serde_core"
 version = "1.0.228"
@@ -453,6 +496,28 @@ dependencies = [
 "syn 2.0.117",
 ]
 [[package]]
 name = "serde_json"
 version = "1.0.149"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "83fc039473c5595ace860d8c4fafa220ff474b3fc6bfdb4293327f1a37e94d86"
 dependencies = [
 "itoa",
 "memchr",
 "serde",
 "serde_core",
 "zmij",
 ]
 [[package]]
 name = "serde_spanned"
 version = "1.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6662b5879511e06e8999a8a235d848113e942c9124f211511b16466ee2995f26"
 dependencies = [
 "serde_core",
 ]
 [[package]]
 name = "simdutf8"
 version = "0.1.5"
@@ -493,6 +558,21 @@ version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "55937e1799185b12863d447f42597ed69d9928686b8d88a1df17376a097d8369"
 [[package]]
 name = "target-triple"
 version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "591ef38edfb78ca4771ee32cf494cb8771944bee237a9b91fc9c1424ac4b777b"
 [[package]]
 name = "termcolor"
 version = "1.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "06794f8f6c5c898b3275aebefa6b8a1cb24cd2c6c79397ab15774837a0bc5755"
 dependencies = [
 "winapi-util",
 ]
 [[package]]
 name = "tinyvec"
 version = "1.11.0"
@@ -508,6 +588,60 @@ version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1f3ccbac311fea05f86f61904b462b55fb3df8837a366dfc601a0161d0532f20"
 [[package]]
 name = "toml"
 version = "1.1.2+spec-1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "81f3d15e84cbcd896376e6730314d59fb5a87f31e4b038454184435cd57defee"
 dependencies = [
 "indexmap",
 "serde_core",
 "serde_spanned",
 "toml_datetime",
 "toml_parser",
 "toml_writer",
 "winnow",
 ]
 [[package]]
 name = "toml_datetime"
 version = "1.1.1+spec-1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3165f65f62e28e0115a00b2ebdd37eb6f3b641855f9d636d3cd4103767159ad7"
 dependencies = [
 "serde_core",
 ]
 [[package]]
 name = "toml_parser"
 version = "1.1.2+spec-1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a2abe9b86193656635d2411dc43050282ca48aa31c2451210f4202550afb7526"
 dependencies = [
 "winnow",
 ]
 [[package]]
 name = "toml_writer"
 version = "1.1.1+spec-1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "756daf9b1013ebe47a8776667b466417e2d4c5679d441c26230efd9ef78692db"
 [[package]]
 name = "trybuild"
 version = "1.0.116"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "47c635f0191bd3a2941013e5062667100969f8c4e9cd787c14f977265d73616e"
 dependencies = [
 "glob",
 "serde",
 "serde_derive",
 "serde_json",
 "target-triple",
 "termcolor",
 "toml",
 ]
 [[package]]
 name = "unicode-ident"
 version = "1.0.24"
@@ -523,6 +657,7 @@ dependencies = [
 "libc",
 "log",
 "rkyv",
 "trybuild",
 ]
 [[package]]
@@ -598,6 +733,15 @@ dependencies = [
 "unicode-ident",
 ]
 [[package]]
 name = "winapi-util"
 version = "0.1.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c2a7b1c03c876122aa43f3020e6c3c3ee5c05081c9a00739faf7503aeba10d22"
 dependencies = [
 "windows-sys",
 ]
 [[package]]
 name = "windows-link"
 version = "0.2.1"
@@ -613,6 +757,12 @@ dependencies = [
 "windows-link",
 ]
 [[package]]
 name = "winnow"
 version = "1.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2ee1708bef14716a11bae175f579062d4554d95be2c6829f518df847b7b3fdd0"
 [[package]]
 name = "wyz"
 version = "0.5.1"
@@ -621,3 +771,9 @@ checksum = "05f360fc0b24296329c78fda852a1e9ae82de9cf7b27dae4b7f62f118f77b9ed"
 dependencies = [
 "tap",
 ]
 [[package]]
 name = "zmij"
 version = "1.0.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b8848ee67ecc8aedbaf3e4122217aff892639231befc6a1b58d29fff4c2cabaa"
@@ -20,6 +20,9 @@ libc = { version = "0.2", optional = true }
 version = "4.5"
 features = ["derive", "env"]
 [dev-dependencies]
 trybuild = "1.0"
 [profile.release]
 opt-level = 3
 lto = true
@@ -0,0 +1,451 @@
 //! # CLI Implementation
 //!
 //! This module provides the interactive CLI implementation for the unshell tree protocol testbed.
 use crate::protocol::{
    FrameType, TreeRequest, TreeResponse, TcpTransport, Transport,
    make_request, make_stream_open, make_stream_data, make_stream_close,
    make_handshake,
 };
 use crate::tree::Tree;
 use crate::leaves::{RemoteShell, TTY};
 use std::string::String;
 use std::vec::Vec;
 /// CLI state - manages connection and local tree.
 ///
 /// # Example
 /// ```
 /// use ush_treetest::cli::Cli;
 ///
 /// let mut cli = Cli::new();
 /// println!("Leaves: {:?}", cli.list_leaves());
 /// ```
 ///
 /// # Fields
 /// * `transport` - Optional TCP transport for remote connection
 /// * `tree` - Local tree for local operations
 /// * `current_path` - Current working path
 /// * `request_id` - Next request ID to send
 /// * `stream_id` - Next stream ID to allocate
 /// * `streams` - Active streams
 /// * `base_path` - Base path assigned by server
 /// * `mode` - Operation mode (Local or Connected)
 pub struct Cli {
    transport: Option<TcpTransport>,
    tree: Tree,
    current_path: String,
    request_id: u64,
    #[allow(dead_code)]
    stream_id: u16,
    streams: Vec<StreamState>,
    base_path: String,
    mode: CliMode,
 }
 /// CLI operation mode.
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 enum CliMode {
    /// Local-only mode
    Local,
    /// Connected to remote server
    Connected,
 }
 /// State of an active stream.
 ///
 /// # Fields
 /// * `stream_id` - The stream identifier
 /// * `path` - The path this stream is connected to
 #[derive(Debug, Clone)]
 #[allow(dead_code)]
 struct StreamState {
    stream_id: u16,
    path: String,
 }
 impl Cli {
    /// Create a new CLI with a local tree.
    ///
    /// The local tree has `/shell` and `/tty` endpoints registered.
    ///
    /// # Example
    /// ```
    /// let cli = Cli::new();
    /// let leaves = cli.list_leaves();
    /// assert!(leaves.contains(&"/shell".to_string()));
    /// ```
    pub fn new() -> Self {
        let mut tree = Tree::new();
        tree.add_endpoint("/shell", Box::new(RemoteShell::new("shell")));
        tree.add_endpoint("/tty", Box::new(TTY::new("tty")));
        Self {
            transport: None,
            tree,
            current_path: String::from("/"),
            request_id: 1,
            stream_id: 1,
            streams: Vec::new(),
            base_path: String::from("/"),
            mode: CliMode::Local,
        }
    }
    /// Get next request ID.
    fn next_request_id(&mut self) -> u64 {
        let id = self.request_id;
        self.request_id += 1;
        id
    }
    /// Get next stream ID.
    #[allow(dead_code)]
    fn next_stream_id(&mut self) -> u16 {
        let id = self.stream_id;
        self.stream_id = self.stream_id.wrapping_add(1);
        id
    }
    /// List nodes at a path.
    ///
    /// # Arguments
    /// * `path` - Optional path (defaults to current path)
    ///
    /// # Returns
    /// List of child node names
    pub fn list_nodes(&self, path: Option<&str>) -> Result<Vec<String>, String> {
        let path = path.unwrap_or(&self.current_path);
        self.tree.list_nodes(path)
    }
    /// List endpoints at a path.
    ///
    /// # Arguments
    /// * `path` - Optional path (defaults to current path)
    pub fn list_endpoints(
        &self,
        path: Option<&str>,
    ) -> Result<Vec<crate::protocol::EndpointInfo>, String> {
        let path = path.unwrap_or(&self.current_path);
        self.tree.list_endpoints(path)
    }
    /// List all leaf paths.
    pub fn list_leaves(&self) -> Vec<String> {
        self.tree.list_leaves()
    }
    /// Get info about a node.
    pub fn get_info(&self, path: &str) -> Result<crate::protocol::NodeInfo, String> {
        self.tree.get_info(path)
    }
    /// Execute a command locally on the tree.
    pub fn exec_local(&mut self, path: &str, cmd: &str) -> Result<TreeResponse, String> {
        let (handler, matched_path) = self
            .tree
            .find_handler(path)
            .ok_or_else(|| format!("path not found: {}", path))?;
        let request = TreeRequest::Exec {
            cmd: cmd.to_string(),
        };
        let mut handler = handler.lock().map_err(|e| e.to_string())?;
        handler.handle_request(&request, matched_path)
    }
    /// Connect to a remote server.
    pub fn connect(&mut self, addr: &str) -> Result<(), String> {
        let transport = TcpTransport::connect(addr).map_err(|e| e.to_string())?;
        self.transport = Some(transport);
        self.mode = CliMode::Connected;
        self.do_handshake()
    }
    /// Perform handshake with remote server.
    fn do_handshake(&mut self) -> Result<(), String> {
        let transport = self.transport.as_mut().ok_or("not connected")?;
        let (header, payload) = make_handshake(vec![self.current_path.clone()]);
        transport
            .send_frame(&header, Some(&payload))
            .map_err(|e| e.to_string())?;
        let (header, payload) = transport.recv_frame().map_err(|e| e.to_string())?;
        if header.frame_type != FrameType::HandshakeAck {
            return Err("unexpected response type".to_string());
        }
        let ack = crate::protocol::HandshakeAck::from_bytes(&payload)
            .map_err(|e| e.to_string())?;
        if !ack.accepted {
            return Err("handshake rejected".to_string());
        }
        self.base_path = ack.assigned_base_path.clone();
        Ok(())
    }
    /// Send a request to the remote server.
    pub fn send_request(
        &mut self,
        dst_path: &str,
        request: &TreeRequest,
    ) -> Result<TreeResponse, String> {
        let request_id = self.next_request_id();
        let transport = self.transport.as_mut().ok_or("not connected")?;
        let full_path = if dst_path.starts_with('/') {
            dst_path.to_string()
        } else {
            format!("{}/{}", self.current_path, dst_path)
        };
        let (header, payload) = make_request(&full_path, &self.base_path, request_id, request);
        transport
            .send_frame(&header, Some(&payload))
            .map_err(|e| e.to_string())?;
        let (header, payload) = transport.recv_frame().map_err(|e| e.to_string())?;
        if header.frame_type != FrameType::Response {
            return Err("unexpected response type".to_string());
        }
        let response = TreeResponse::from_bytes(&payload).map_err(|e| e.to_string())?;
        Ok(response)
    }
    /// Open a stream to a remote path.
    pub fn open_stream(&mut self, dst_path: &str) -> Result<u16, String> {
        let request_id = self.next_request_id();
        let transport = self.transport.as_mut().ok_or("not connected")?;
        let full_path = if dst_path.starts_with('/') {
            dst_path.to_string()
        } else {
            format!("{}/{}", self.current_path, dst_path)
        };
        let header = make_stream_open(&full_path, &self.base_path, request_id);
        transport.send_frame(&header, None).map_err(|e| e.to_string())?;
        let (header, payload) = transport.recv_frame().map_err(|e| e.to_string())?;
        if header.frame_type != FrameType::Response {
            return Err("unexpected response type".to_string());
        }
        let response = TreeResponse::from_bytes(&payload).map_err(|e| e.to_string())?;
        match response {
            TreeResponse::StreamOpened { stream_id } => {
                self.streams.push(StreamState {
                    stream_id,
                    path: full_path,
                });
                Ok(stream_id)
            }
            _ => Err("expected StreamOpened".to_string()),
        }
    }
    /// Send data on a stream.
    pub fn send_stream_data(&mut self, stream_id: u16, data: &[u8]) -> Result<(), String> {
        let transport = self.transport.as_mut().ok_or("not connected")?;
        let (header, payload) = make_stream_data(stream_id, data);
        transport
            .send_frame(&header, Some(&payload))
            .map_err(|e| e.to_string())
    }
    /// Close a stream.
    pub fn close_stream(&mut self, stream_id: u16) -> Result<(), String> {
        let transport = self.transport.as_mut().ok_or("not connected")?;
        let header = make_stream_close(stream_id);
        transport
            .send_frame(&header, None)
            .map_err(|e| e.to_string())?;
        self.streams.retain(|s| s.stream_id != stream_id);
        Ok(())
    }
    /// Check if connected to remote.
    pub fn is_connected(&self) -> bool {
        matches!(self.mode, CliMode::Connected)
    }
    /// Get current path.
    pub fn current_path(&self) -> &str {
        &self.current_path
    }
    /// Set current path.
    pub fn set_path(&mut self, path: &str) {
        self.current_path = path.to_string();
    }
 }
 /// Parse and execute a CLI command.
 ///
 /// # Arguments
 /// * `cli` - The CLI state
 /// * `line` - The command line to parse
 ///
 /// # Returns
 /// Ok(output) on success, Err(error) on failure
 ///
 /// # Example
 /// ```
 /// use ush_treetest::cli::{Cli, parse_and_execute};
 ///
 /// let mut cli = Cli::new();
 /// let output = parse_and_execute(&mut cli, "leaves").unwrap();
 /// assert!(output.contains("shell"));
 /// ```
 pub fn parse_and_execute(cli: &mut Cli, line: &str) -> Result<String, String> {
    let parts: Vec<&str> = line.split_whitespace().collect();
    if parts.is_empty() {
        return Ok(String::new());
    }
    match parts[0] {
        "ls" | "list" => {
            let path = parts.get(1).copied();
            let names = cli.list_nodes(path)?;
            Ok(names.join("\n"))
        }
        "endpoints" => {
            let path = parts.get(1).copied();
            let eps = cli.list_endpoints(path)?;
            let mut output = String::new();
            for ep in &eps {
                output.push_str(&format!("{} ({:?}) at {}\n", ep.name, ep.endpoint_type, ep.path));
            }
            Ok(output)
        }
        "leaves" => Ok(cli.list_leaves().join("\n")),
        "info" => {
            if parts.len() < 2 {
                return Err("usage: info <path>".to_string());
            }
            let info = cli.get_info(parts[1])?;
            Ok(format!("{:?}", info))
        }
        "exec" => {
            if parts.len() < 3 {
                return Err("usage: exec <path> <command>".to_string());
            }
            let path = parts[1];
            let cmd = parts[2..].join(" ");
            if cli.is_connected() {
                let request = TreeRequest::Exec {
                    cmd: cmd.clone(),
                };
                let response = cli.send_request(path, &request)?;
                format_response(response)
            } else {
                let response = cli.exec_local(path, &cmd)?;
                format_response(response)
            }
        }
        "cd" => {
            if parts.len() < 2 {
                return Err("usage: cd <path>".to_string());
            }
            let path = parts[1];
            if cli.get_info(path).is_ok() {
                cli.set_path(path);
                Ok(format!("changed to {}", path))
            } else {
                Err(format!("path not found: {}", path))
            }
        }
        "pwd" => Ok(cli.current_path().to_string()),
        "connect" => {
            if parts.len() < 2 {
                return Err("usage: connect <host:port>".to_string());
            }
            cli.connect(parts[1])?;
            Ok(format!("connected to {}", parts[1]))
        }
        "stream" => {
            if parts.len() < 2 {
                return Err("usage: stream <path>".to_string());
            }
            if !cli.is_connected() {
                return Err("not connected".to_string());
            }
            let stream_id = cli.open_stream(parts[1])?;
            Ok(format!("opened stream {} to {}", stream_id, parts[1]))
        }
        "close" => {
            if parts.len() < 2 {
                return Err("usage: close <stream_id>".to_string());
            }
            let stream_id: u16 = parts[1].parse().map_err(|_| "invalid stream id".to_string())?;
            cli.close_stream(stream_id)?;
            Ok(format!("closed stream {}", stream_id))
        }
        "send" => {
            if parts.len() < 3 {
                return Err("usage: send <stream_id> <data>".to_string());
            }
            let stream_id: u16 = parts[1].parse().map_err(|_| "invalid stream id".to_string())?;
            let data = parts[2..].join(" ");
            cli.send_stream_data(stream_id, data.as_bytes())?;
            Ok("sent".to_string())
        }
        "help" => Ok(HELP_TEXT.to_string()),
        _ => Err(format!("unknown command: {}", parts[0])),
    }
 }
 /// Format a TreeResponse for display.
 fn format_response(response: TreeResponse) -> Result<String, String> {
    match response {
        TreeResponse::NodeList { names } => Ok(names.join("\n")),
        TreeResponse::EndpointList { endpoints } => {
            let mut output = String::new();
            for ep in endpoints {
                output.push_str(&format!("{} ({:?})\n", ep.name, ep.endpoint_type));
            }
            Ok(output)
        }
        TreeResponse::LeafList { leaves } => Ok(leaves.join("\n")),
        TreeResponse::NodeInfo { info } => Ok(format!(
            "path: {}\nis_leaf: {}\nhas_children: {}\nendpoints: {:?}",
            info.path, info.is_leaf, info.has_children, info.endpoints
        )),
        TreeResponse::ExecOutput {
            exit_code,
            stdout,
            stderr,
        } => {
            let mut output = String::new();
            output.push_str(&format!("exit code: {}\n", exit_code));
            if !stdout.is_empty() {
                output.push_str(&format!("stdout: {}\n", String::from_utf8_lossy(&stdout)));
            }
            if !stderr.is_empty() {
                output.push_str(&format!("stderr: {}\n", String::from_utf8_lossy(&stderr)));
            }
            Ok(output)
        }
        TreeResponse::StreamOpened { stream_id } => Ok(format!("stream opened: {}", stream_id)),
    }
 }
 /// Help text for CLI commands.
 const HELP_TEXT: &str = r#"Commands:
  ls [path]           List child nodes
  endpoints [path]    List endpoints at path
  leaves              List all leaf paths
  info <path>         Get node info
  exec <path> <cmd>   Execute command at path
  cd <path>           Change current path
  pwd                 Print working path
  connect <host>      Connect to remote server
  stream <path>       Open stream to path
  send <id> <data>    Send data on stream
  close <id>          Close stream
  help                Show this help
 "#;
@@ -2,342 +2,17 @@
 //!
 //! This module provides the interactive CLI for the unshell tree protocol testbed.
 //! It supports both local tree operations and remote connections.
 //!
 //! # Usage
 //!
 //! ```no_run
 //! use ush_treetest::cli::{Cli, parse_and_execute};
 //!
 //! let mut cli = Cli::new();
 //! let output = parse_and_execute(&mut cli, "leaves").unwrap();
 //! println!("{}", output);
 //! ```
-use crate::protocol::{
+pub mod cli;
    FrameType, TreeRequest, TreeResponse, TcpTransport, Transport,
    make_request, make_stream_open, make_stream_data, make_stream_close,
    make_handshake,
 };
 use crate::tree::Tree;
 use crate::leaves::{RemoteShell, TTY};
 use std::string::String;
 use std::vec::Vec;
 use std::boxed::Box;
 use std::result::Result;
-/// CLI state - manages connection and local tree
+pub use cli::{Cli, parse_and_execute};
 pub struct Cli {
    transport: Option<TcpTransport>,
    tree: Tree,
    current_path: String,
    request_id: u64,
    #[allow(dead_code)]
    stream_id: u16,
    streams: Vec<StreamState>,
    base_path: String,
    mode: CliMode,
 }
 /// CLI operation mode
 #[derive(Debug, Clone, Copy)]
 enum CliMode { Local, Connected }
 /// State of an open stream
 #[derive(Debug)]
 #[allow(dead_code)]
 struct StreamState { stream_id: u16, path: String }
 impl Cli {
    /// Create a new CLI with a local tree
    pub fn new() -> Self {
        let mut tree = Tree::new();
        tree.add_endpoint("/shell", Box::new(RemoteShell::new("shell")));
        tree.add_endpoint("/tty", Box::new(TTY::new("tty")));
        Self { 
            transport: None, 
            tree, 
            current_path: String::from("/"), 
            request_id: 1, 
            stream_id: 1, 
            streams: Vec::new(), 
            base_path: String::from("/"), 
            mode: CliMode::Local 
        }
    }
    /// Get next request ID
    fn next_request_id(&mut self) -> u64 { 
        let id = self.request_id; 
        self.request_id += 1; 
        id 
    }
    /// Get next stream ID
    #[allow(dead_code)]
    fn next_stream_id(&mut self) -> u16 { 
        let id = self.stream_id; 
        self.stream_id = self.stream_id.wrapping_add(1); 
        id 
    }
    /// List nodes at a path
    pub fn list_nodes(&self, path: Option<&str>) -> Result<Vec<String>, String> {
        let path = path.unwrap_or(&self.current_path);
        self.tree.list_nodes(path)
    }
    /// List endpoints at a path
    pub fn list_endpoints(&self, path: Option<&str>) -> Result<Vec<crate::protocol::EndpointInfo>, String> {
        let path = path.unwrap_or(&self.current_path);
        self.tree.list_endpoints(path)
    }
    /// List all leaf paths
    pub fn list_leaves(&self) -> Vec<String> { 
        self.tree.list_leaves() 
    }
    /// Get info about a node
    pub fn get_info(&self, path: &str) -> Result<crate::protocol::NodeInfo, String> { 
        self.tree.get_info(path) 
    }
    /// Execute a command locally on the tree
    pub fn exec_local(&mut self, path: &str, cmd: &str) -> Result<TreeResponse, String> {
        let (handler, matched_path) = self.tree.find_handler(path)
            .ok_or_else(|| format!("path not found: {}", path))?;
        let request = TreeRequest::Exec { cmd: cmd.to_string() };
        // Lock the handler and make the request
        let mut handler = handler.lock().map_err(|e| e.to_string())?;
        handler.handle_request(&request, matched_path)
    }
    /// Connect to a remote server
    pub fn connect(&mut self, addr: &str) -> Result<(), String> {
        let transport = TcpTransport::connect(addr).map_err(|e| e.to_string())?;
        self.transport = Some(transport);
        self.mode = CliMode::Connected;
        self.do_handshake()
    }
    /// Perform handshake with remote server
    fn do_handshake(&mut self) -> Result<(), String> {
        let transport = self.transport.as_mut().ok_or("not connected")?;
        let (header, payload) = make_handshake(vec![self.current_path.clone()]);
        transport.send_frame(&header, Some(&payload)).map_err(|e| e.to_string())?;
        let (header, payload) = transport.recv_frame().map_err(|e| e.to_string())?;
        if header.frame_type != FrameType::HandshakeAck { return Err("unexpected response type".to_string()); }
        let ack = crate::protocol::HandshakeAck::from_bytes(&payload).map_err(|e| e.to_string())?;
        if !ack.accepted { return Err("handshake rejected".to_string()); }
        self.base_path = ack.assigned_base_path.clone();
        Ok(())
    }
    /// Send a request to the remote server
    pub fn send_request(&mut self, dst_path: &str, request: &TreeRequest) -> Result<TreeResponse, String> {
        // Get request_id first to avoid borrow issues
        let request_id = self.next_request_id();
        let transport = self.transport.as_mut().ok_or("not connected")?;
        let full_path = if dst_path.starts_with('/') { 
            dst_path.to_string() 
        } else { 
            format!("{}/{}", self.current_path, dst_path) 
        };
        let (header, payload) = make_request(&full_path, &self.base_path, request_id, request);
        transport.send_frame(&header, Some(&payload)).map_err(|e| e.to_string())?;
        let (header, payload) = transport.recv_frame().map_err(|e| e.to_string())?;
        if header.frame_type != FrameType::Response { return Err("unexpected response type".to_string()); }
        let response = TreeResponse::from_bytes(&payload).map_err(|e| e.to_string())?;
        Ok(response)
    }
    /// Open a stream to a remote path
    pub fn open_stream(&mut self, dst_path: &str) -> Result<u16, String> {
        // Get request_id first
        let request_id = self.next_request_id();
        let transport = self.transport.as_mut().ok_or("not connected")?;
        let full_path = if dst_path.starts_with('/') { 
            dst_path.to_string() 
        } else { 
            format!("{}/{}", self.current_path, dst_path) 
        };
        let header = make_stream_open(&full_path, &self.base_path, request_id);
        transport.send_frame(&header, None).map_err(|e| e.to_string())?;
        let (header, payload) = transport.recv_frame().map_err(|e| e.to_string())?;
        if header.frame_type != FrameType::Response { return Err("unexpected response type".to_string()); }
        let response = TreeResponse::from_bytes(&payload).map_err(|e| e.to_string())?;
        match response { 
            TreeResponse::StreamOpened { stream_id } => { 
                self.streams.push(StreamState { stream_id, path: full_path }); 
                Ok(stream_id) 
            } 
            _ => Err("expected StreamOpened".to_string()) 
        }
    }
    /// Send data on a stream
    pub fn send_stream_data(&mut self, stream_id: u16, data: &[u8]) -> Result<(), String> {
        let transport = self.transport.as_mut().ok_or("not connected")?;
        let (header, payload) = make_stream_data(stream_id, data);
        transport.send_frame(&header, Some(&payload)).map_err(|e| e.to_string())
    }
    /// Close a stream
    pub fn close_stream(&mut self, stream_id: u16) -> Result<(), String> {
        let transport = self.transport.as_mut().ok_or("not connected")?;
        let header = make_stream_close(stream_id);
        transport.send_frame(&header, None).map_err(|e| e.to_string())?;
        self.streams.retain(|s| s.stream_id != stream_id);
        Ok(())
    }
    /// Check if connected to remote
    pub fn is_connected(&self) -> bool { 
        matches!(self.mode, CliMode::Connected) 
    }
    /// Get current path
    pub fn current_path(&self) -> &str { 
        &self.current_path 
    }
    /// Set current path
    pub fn set_path(&mut self, path: &str) { 
        self.current_path = path.to_string(); 
    }
 }
 /// Parse and execute a CLI command
 /// 
 /// # Arguments
 /// * `cli` - The CLI state
 /// * `line` - The command line to parse
 /// 
 /// # Returns
 /// Ok(output) on success, Err(error) on failure
 pub fn parse_and_execute(cli: &mut Cli, line: &str) -> Result<String, String> {
    let parts: Vec<&str> = line.split_whitespace().collect();
    if parts.is_empty() { return Ok(String::new()); }
    match parts[0] {
        "ls" | "list" => { 
            let path = parts.get(1).map(|s| *s); 
            let names = cli.list_nodes(path)?; 
            Ok(names.join("\n")) 
        }
        "endpoints" => { 
            let path = parts.get(1).map(|s| *s); 
            let eps = cli.list_endpoints(path)?; 
            let mut output = String::new(); 
            for ep in &eps { 
                output.push_str(&format!("{} ({:?}) at {}\n", ep.name, ep.endpoint_type, ep.path)); 
            } 
            Ok(output) 
        }
        "leaves" => { 
            Ok(cli.list_leaves().join("\n")) 
        }
        "info" => { 
            if parts.len() < 2 { return Err("usage: info <path>".to_string()); } 
            let info = cli.get_info(parts[1])?; 
            Ok(format!("{:?}", info)) 
        }
        "exec" => {
            if parts.len() < 3 { return Err("usage: exec <path> <command>".to_string()); }
            let path = parts[1]; 
            let cmd = parts[2..].join(" ");
            if cli.is_connected() { 
                let request = TreeRequest::Exec { cmd: cmd.clone() }; 
                let response = cli.send_request(path, &request)?; 
                format_response(response) 
            } else { 
                let response = cli.exec_local(path, &cmd)?; 
                format_response(response) 
            }
        }
        "cd" => { 
            if parts.len() < 2 { return Err("usage: cd <path>".to_string()); } 
            let path = parts[1]; 
            if cli.get_info(path).is_ok() { 
                cli.set_path(path); 
                Ok(format!("changed to {}", path)) 
            } else { 
                Err(format!("path not found: {}", path)) 
            } 
        }
        "pwd" => { 
            Ok(cli.current_path().to_string()) 
        }
        "connect" => { 
            if parts.len() < 2 { return Err("usage: connect <host:port>".to_string()); } 
            cli.connect(parts[1])?; 
            Ok(format!("connected to {}", parts[1])) 
        }
        "stream" => { 
            if parts.len() < 2 { return Err("usage: stream <path>".to_string()); } 
            if !cli.is_connected() { return Err("not connected".to_string()); } 
            let stream_id = cli.open_stream(parts[1])?; 
            Ok(format!("opened stream {} to {}", stream_id, parts[1])) 
        }
        "close" => { 
            if parts.len() < 2 { return Err("usage: close <stream_id>".to_string()); } 
            let stream_id: u16 = parts[1].parse().map_err(|_| "invalid stream id".to_string())?; 
            cli.close_stream(stream_id)?; 
            Ok(format!("closed stream {}", stream_id)) 
        }
        "send" => { 
            if parts.len() < 3 { return Err("usage: send <stream_id> <data>".to_string()); } 
            let stream_id: u16 = parts[1].parse().map_err(|_| "invalid stream id".to_string())?; 
            let data = parts[2..].join(" "); 
            cli.send_stream_data(stream_id, data.as_bytes())?; 
            Ok("sent".to_string()) 
        }
        "help" => { 
            Ok(HELP_TEXT.to_string()) 
        }
        _ => Err(format!("unknown command: {}", parts[0])),
    }
 }
 /// Format a TreeResponse for display
 fn format_response(response: TreeResponse) -> Result<String, String> {
    match response {
        TreeResponse::NodeList { names } => Ok(names.join("\n")),
        TreeResponse::EndpointList { endpoints } => { 
            let mut output = String::new(); 
            for ep in endpoints { 
                output.push_str(&format!("{} ({:?})\n", ep.name, ep.endpoint_type)); 
            } 
            Ok(output) 
        }
        TreeResponse::LeafList { leaves } => Ok(leaves.join("\n")),
        TreeResponse::NodeInfo { info } => Ok(format!("path: {}\nis_leaf: {}\nhas_children: {}\nendpoints: {:?}", info.path, info.is_leaf, info.has_children, info.endpoints)),
        TreeResponse::ExecOutput { exit_code, stdout, stderr } => { 
            let mut output = String::new(); 
            output.push_str(&format!("exit code: {}\n", exit_code)); 
            if !stdout.is_empty() { output.push_str(&format!("stdout: {}\n", String::from_utf8_lossy(&stdout))); } 
            if !stderr.is_empty() { output.push_str(&format!("stderr: {}\n", String::from_utf8_lossy(&stderr))); } 
            Ok(output) 
        }
        TreeResponse::StreamOpened { stream_id } => Ok(format!("stream opened: {}", stream_id)),
    }
 }
 /// Help text for CLI commands
 const HELP_TEXT: &str = r#"Commands:
  ls [path]           List child nodes
  endpoints [path]    List endpoints at path
  leaves              List all leaf paths
  info <path>         Get node info
  exec <path> <cmd>   Execute command at path
  cd <path>           Change current path
  pwd                 Print working path
  connect <host>      Connect to remote server
  stream <path>       Open stream to path
  send <id> <data>    Send data on stream
  close <id>          Close stream
  help                Show this help
 "#;
@@ -0,0 +1,434 @@
 //! # Client Implementation
 //!
 //! This module provides the client functionality for connecting to servers,
 //! sending requests, and managing streams.
 use crate::protocol::{
    FrameType, TreeRequest, TreeResponse, TcpTransport, Transport,
    make_request, make_stream_open, make_stream_data, make_stream_close,
    make_handshake,
 };
 use crate::tree::Tree;
 use crate::leaves::{RemoteShell, TTY};
 use std::string::String;
 use std::vec::Vec;
 use std::fmt;
 /// Client state - manages connection and local tree.
 ///
 /// # Example
 /// ```
 /// use ush_treetest::client::Client;
 ///
 /// // Start with local tree
 /// let mut client = Client::new_local();
 /// println!("Leaves: {:?}", client.list_leaves());
 ///
 /// // Connect to remote server
 /// client.connect("localhost:8080").unwrap();
 /// ```
 ///
 /// # Fields
 /// * `transport` - Optional TCP transport for remote connection
 /// * `tree` - Local tree for local operations
 /// * `current_path` - Current working path
 /// * `request_id` - Next request ID to send
 /// * `stream_id` - Next stream ID to allocate
 /// * `streams` - Active streams
 /// * `base_path` - Base path assigned by server
 /// * `mode` - Operation mode (Local or Connected)
 #[allow(dead_code)]
 pub struct Client {
    transport: Option<TcpTransport>,
    #[allow(dead_code)]
    tree: Tree,
    current_path: String,
    request_id: u64,
    #[allow(dead_code)]
    stream_id: u16,
    streams: Vec<StreamState>,
    base_path: String,
    mode: ClientMode,
 }
 impl fmt::Debug for Client {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("Client")
            .field("transport", &self.transport.is_some())
            .field("current_path", &self.current_path)
            .field("mode", &self.mode)
            .finish()
    }
 }
 /// Client operation mode.
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 #[allow(dead_code)]
 enum ClientMode {
    /// Local-only mode (no remote connection)
    Local,
    /// Connected to remote server
    Connected,
 }
 /// State of an open stream.
 ///
 /// # Fields
 /// * `stream_id` - The stream identifier
 /// * `path` - The path this stream is connected to
 #[derive(Debug, Clone)]
 #[allow(dead_code)]
 struct StreamState {
    stream_id: u16,
    path: String,
 }
 #[allow(dead_code)]
 impl Client {
    /// Create a new client with a local tree.
    ///
    /// The local tree has `/shell` and `/tty` endpoints registered.
    ///
    /// # Example
    /// ```
    /// let mut client = Client::new_local();
    /// let leaves = client.list_leaves();
    /// assert!(leaves.contains(&"/shell".to_string()));
    /// ```
    pub fn new_local() -> Self {
        let mut tree = Tree::new();
        tree.add_endpoint("/shell", Box::new(RemoteShell::new("shell")));
        tree.add_endpoint("/tty", Box::new(TTY::new("tty")));
        Self {
            transport: None,
            tree,
            current_path: String::from("/"),
            request_id: 1,
            stream_id: 1,
            streams: Vec::new(),
            base_path: String::from("/"),
            mode: ClientMode::Local,
        }
    }
    /// Get the next request ID.
    ///
    /// Each request gets a unique incrementing ID.
    fn next_request_id(&mut self) -> u64 {
        let id = self.request_id;
        self.request_id += 1;
        id
    }
    /// Get the next stream ID.
    #[allow(dead_code)]
    fn next_stream_id(&mut self) -> u16 {
        let id = self.stream_id;
        self.stream_id = self.stream_id.wrapping_add(1);
        id
    }
    /// List nodes at a path.
    ///
    /// # Arguments
    /// * `path` - Optional path (defaults to current path)
    ///
    /// # Returns
    /// List of child node names
    ///
    /// # Example
    /// ```
    /// let mut client = Client::new_local();
    /// let nodes = client.list_nodes(None).unwrap();
    /// ```
    pub fn list_nodes(&self, path: Option<&str>) -> Result<Vec<String>, String> {
        let path = path.unwrap_or(&self.current_path);
        self.tree.list_nodes(path)
    }
    /// List endpoints at a path.
    ///
    /// # Arguments
    /// * `path` - Optional path (defaults to current path)
    ///
    /// # Returns
    /// List of endpoint information
    pub fn list_endpoints(
        &self,
        path: Option<&str>,
    ) -> Result<Vec<crate::protocol::EndpointInfo>, String> {
        let path = path.unwrap_or(&self.current_path);
        self.tree.list_endpoints(path)
    }
    /// List all leaf paths.
    ///
    /// # Returns
    /// List of leaf node paths
    ///
    /// # Example
    /// ```
    /// let client = Client::new_local();
    /// let leaves = client.list_leaves();
    /// assert!(!leaves.is_empty());
    /// ```
    pub fn list_leaves(&self) -> Vec<String> {
        self.tree.list_leaves()
    }
    /// Get information about a node.
    ///
    /// # Arguments
    /// * `path` - The path to get info about
    ///
    /// # Returns
    /// Node information
    ///
    /// # Example
    /// ```
    /// let client = Client::new_local();
    /// let info = client.get_info("/shell").unwrap();
    /// assert!(info.is_leaf);
    /// ```
    pub fn get_info(&self, path: &str) -> Result<crate::protocol::NodeInfo, String> {
        self.tree.get_info(path)
    }
    /// Execute a command locally on the tree.
    ///
    /// # Arguments
    /// * `path` - The path to execute at
    /// * `cmd` - The command to execute
    ///
    /// # Returns
    /// Execution response with exit code and output
    pub fn exec_local(&mut self, path: &str, cmd: &str) -> Result<TreeResponse, String> {
        let (handler, matched_path) = self
            .tree
            .find_handler(path)
            .ok_or_else(|| format!("path not found: {}", path))?;
        let request = TreeRequest::Exec {
            cmd: cmd.to_string(),
        };
        let mut handler = handler.lock().map_err(|e| e.to_string())?;
        handler.handle_request(&request, matched_path)
    }
    /// Connect to a remote server.
    ///
    /// # Arguments
    /// * `addr` - The server address (e.g., "localhost:8080")
    ///
    /// # Returns
    /// Ok(()) on success
    ///
    /// # Example
    /// ```
    /// let mut client = Client::new_local();
    /// client.connect("localhost:8080").unwrap();
    /// ```
    pub fn connect(&mut self, addr: &str) -> Result<(), String> {
        let transport = TcpTransport::connect(addr).map_err(|e| e.to_string())?;
        self.transport = Some(transport);
        self.mode = ClientMode::Connected;
        self.do_handshake()
    }
    /// Perform handshake with remote server.
    fn do_handshake(&mut self) -> Result<(), String> {
        let transport = self.transport.as_mut().ok_or("not connected")?;
        let (header, payload) = make_handshake(vec![self.current_path.clone()]);
        transport
            .send_frame(&header, Some(&payload))
            .map_err(|e| e.to_string())?;
        let (header, payload) = transport.recv_frame().map_err(|e| e.to_string())?;
        if header.frame_type != FrameType::HandshakeAck {
            return Err("unexpected response type".to_string());
        }
        let ack = crate::protocol::HandshakeAck::from_bytes(&payload)
            .map_err(|e| e.to_string())?;
        if !ack.accepted {
            return Err("handshake rejected".to_string());
        }
        self.base_path = ack.assigned_base_path.clone();
        Ok(())
    }
    /// Send a request to the remote server.
    ///
    /// # Arguments
    /// * `dst_path` - The destination path
    /// * `request` - The request to send
    ///
    /// # Returns
    /// The response from the server
    ///
    /// # Example
    /// ```
    /// let mut client = Client::new_local();
    /// client.connect("localhost:8080").unwrap();
    ///
    /// let request = TreeRequest::Exec { cmd: "echo hello".to_string() };
    /// let response = client.send_request("/shell", &request).unwrap();
    /// ```
    pub fn send_request(&mut self, dst_path: &str, request: &TreeRequest) -> Result<TreeResponse, String> {
        let request_id = self.next_request_id();
        let transport = self.transport.as_mut().ok_or("not connected")?;
        let full_path = if dst_path.starts_with('/') {
            dst_path.to_string()
        } else {
            format!("{}/{}", self.current_path, dst_path)
        };
        let (header, payload) = make_request(&full_path, &self.base_path, request_id, request);
        transport
            .send_frame(&header, Some(&payload))
            .map_err(|e| e.to_string())?;
        let (header, payload) = transport.recv_frame().map_err(|e| e.to_string())?;
        if header.frame_type != FrameType::Response {
            return Err("unexpected response type".to_string());
        }
        let response = TreeResponse::from_bytes(&payload).map_err(|e| e.to_string())?;
        Ok(response)
    }
    /// Open a stream to a remote path.
    ///
    /// # Arguments
    /// * `dst_path` - The destination path
    ///
    /// # Returns
    /// The stream ID on success
    ///
    /// # Example
    /// ```
    /// let mut client = Client::new_local();
    /// client.connect("localhost:8080").unwrap();
    /// let stream_id = client.open_stream("/tty").unwrap();
    /// ```
    pub fn open_stream(&mut self, dst_path: &str) -> Result<u16, String> {
        let request_id = self.next_request_id();
        let transport = self.transport.as_mut().ok_or("not connected")?;
        let full_path = if dst_path.starts_with('/') {
            dst_path.to_string()
        } else {
            format!("{}/{}", self.current_path, dst_path)
        };
        let header = make_stream_open(&full_path, &self.base_path, request_id);
        transport.send_frame(&header, None).map_err(|e| e.to_string())?;
        let (header, payload) = transport.recv_frame().map_err(|e| e.to_string())?;
        if header.frame_type != FrameType::Response {
            return Err("unexpected response type".to_string());
        }
        let response = TreeResponse::from_bytes(&payload).map_err(|e| e.to_string())?;
        match response {
            TreeResponse::StreamOpened { stream_id } => {
                self.streams.push(StreamState {
                    stream_id,
                    path: full_path,
                });
                Ok(stream_id)
            }
            _ => Err("expected StreamOpened".to_string()),
        }
    }
    /// Send data on a stream.
    ///
    /// # Arguments
    /// * `stream_id` - The stream ID
    /// * `data` - The data to send
    ///
    /// # Example
    /// ```
    /// let mut client = Client::new_local();
    /// client.connect("localhost:8080").unwrap();
    /// let stream_id = client.open_stream("/tty").unwrap();
    /// client.send_stream_data(stream_id, b"hello").unwrap();
    /// ```
    pub fn send_stream_data(&mut self, stream_id: u16, data: &[u8]) -> Result<(), String> {
        let transport = self.transport.as_mut().ok_or("not connected")?;
        let (header, payload) = make_stream_data(stream_id, data);
        transport
            .send_frame(&header, Some(&payload))
            .map_err(|e| e.to_string())
    }
    /// Close a stream.
    ///
    /// # Arguments
    /// * `stream_id` - The stream ID to close
    ///
    /// # Example
    /// ```
    /// let mut client = Client::new_local();
    /// client.connect("localhost:8080").unwrap();
    /// let stream_id = client.open_stream("/tty").unwrap();
    /// client.close_stream(stream_id).unwrap();
    /// ```
    pub fn close_stream(&mut self, stream_id: u16) -> Result<(), String> {
        let transport = self.transport.as_mut().ok_or("not connected")?;
        let header = make_stream_close(stream_id);
        transport
            .send_frame(&header, None)
            .map_err(|e| e.to_string())?;
        self.streams.retain(|s| s.stream_id != stream_id);
        Ok(())
    }
    /// Check if connected to remote.
    ///
    /// # Returns
    /// True if connected to a remote server
    ///
    /// # Example
    /// ```
    /// let client = Client::new_local();
    /// assert!(!client.is_connected());
    /// ```
    pub fn is_connected(&self) -> bool {
        matches!(self.mode, ClientMode::Connected)
    }
    /// Get current path.
    ///
    /// # Returns
    /// The current working path
    ///
    /// # Example
    /// ```
    /// let client = Client::new_local();
    /// assert_eq!(client.current_path(), "/");
    /// ```
    pub fn current_path(&self) -> &str {
        &self.current_path
    }
    /// Set current path.
    ///
    /// # Arguments
    /// * `path` - The new current path
    ///
    /// # Example
    /// ```
    /// let mut client = Client::new_local();
    /// client.set_path("/shell");
    /// assert_eq!(client.current_path(), "/shell");
    /// ```
    pub fn set_path(&mut self, path: &str) {
        self.current_path = path.to_string();
    }
 }
@@ -1,37 +1,101 @@
 //! # RemoteShell Leaf
 //!
 //! This module provides command execution functionality.
 use crate::protocol::{TreeRequest, TreeResponse, EndpointType};
 use crate::tree::Endpoint;
 use std::string::String;
 use std::vec::Vec;
 use std::result::Result;
 use std::fmt;
-pub struct RemoteShell { name: String }
+/// RemoteShell - executes commands locally.
 ///
 /// # Example
 /// ```
 /// use ush_treetest::leaves::RemoteShell;
 ///
 /// let shell = RemoteShell::new("shell");
 /// ```
 pub struct RemoteShell {
    name: String,
 }
 impl RemoteShell {
-    pub fn new(name: &str) -> Self { Self { name: name.to_string() } }
+    /// Create a new RemoteShell endpoint.
    ///
    /// # Arguments
    /// * `name` - The name for this endpoint
    pub fn new(name: &str) -> Self {
        Self {
            name: name.to_string(),
        }
    }
    fn execute(&self, cmd: &str) -> (i32, Vec<u8>, Vec<u8>) {
        use std::process::{Command, Stdio};
-        match Command::new("sh").args(["-c", cmd]).stdout(Stdio::piped()).stderr(Stdio::piped()).output() {
+        match Command::new("sh")
            .args(["-c", cmd])
            .stdout(Stdio::piped())
            .stderr(Stdio::piped())
            .output()
        {
            Ok(out) => (out.status.code().unwrap_or(-1), out.stdout, out.stderr),
            Err(e) => (-1, Vec::new(), format!("{}\n", e).into_bytes()),
        }
    }
 }
 impl fmt::Debug for RemoteShell {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("RemoteShell")
            .field("name", &self.name)
            .finish()
    }
 }
 impl Endpoint for RemoteShell {
-    fn handle_request(&mut self, request: &TreeRequest, _src_path: &str) -> Result<TreeResponse, String> {
+    fn handle_request(
        &mut self,
        request: &TreeRequest,
        _src_path: &str,
    ) -> Result<TreeResponse, String> {
        match request {
            TreeRequest::Exec { cmd } => {
                let (exit_code, stdout, stderr) = self.execute(cmd);
-                Ok(TreeResponse::ExecOutput { exit_code, stdout, stderr })
+                Ok(TreeResponse::ExecOutput {
                    exit_code,
                    stdout,
                    stderr,
                })
            }
            _ => Err("unsupported request".to_string()),
        }
    }
-    fn on_stream_open(&mut self, _stream_id: u16, _src_path: &str) -> Option<u16> { None }
+
-    fn on_stream_data(&mut self, _stream_id: u16, _data: &[u8]) -> bool { false }
+    fn on_stream_open(
        &mut self,
        _stream_id: u16,
        _src_path: &str,
    ) -> Option<u16> {
        None
    }
    fn on_stream_data(
        &mut self,
        _stream_id: u16,
        _data: &[u8],
    ) -> bool {
        false
    }
    fn on_stream_close(&mut self, _stream_id: u16) {}
-    fn endpoint_type(&self) -> EndpointType { EndpointType::Leaf }
+
-    fn name(&self) -> &str { &self.name }
+    fn endpoint_type(&self) -> EndpointType {
        EndpointType::Leaf
    }
    fn name(&self) -> &str {
        &self.name
    }
 }
@@ -8,8 +8,9 @@ use crate::tree::Endpoint;
 use std::boxed::Box;
 use std::result::Result;
 use std::collections::HashMap;
 use std::fmt;
-/// A PTY session - represents an active terminal session
+/// A PTY session - represents an active terminal session.
 #[allow(dead_code)]
 pub struct PtySession {
    /// Stream ID for this session
@@ -17,10 +18,19 @@ pub struct PtySession {
    /// Master file descriptor for the PTY
    pub master: std::os::unix::io::RawFd,
    /// Child process PID
-    pub child_pid: u32 
+    pub child_pid: u32,
 }
-/// TTY endpoint - provides PTY streaming functionality
+impl fmt::Debug for PtySession {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("PtySession")
            .field("stream_id", &self.stream_id)
            .field("child_pid", &self.child_pid)
            .finish()
    }
 }
 /// TTY endpoint - provides PTY streaming functionality.
 pub struct TTY {
    name: String,
    sessions: HashMap<u16, Box<PtySession>>,
@@ -28,17 +38,29 @@ pub struct TTY {
    next_id: u16,
 }
 impl fmt::Debug for TTY {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("TTY")
            .field("name", &self.name)
            .field("sessions", &self.sessions.len())
            .finish()
    }
 }
 impl TTY {
-    /// Create a new TTY endpoint
+    /// Create a new TTY endpoint.
    ///
    /// # Arguments
    /// * `name` - The name for this endpoint
    pub fn new(name: &str) -> Self {
        Self {
            name: name.to_string(),
            sessions: HashMap::new(),
-            next_id: 1 
+            next_id: 1,
        }
    }
-    /// Open a new PTY session
+    /// Open a new PTY session.
    ///
    /// # Arguments
    /// * `stream_id` - The stream ID for this session
@@ -46,25 +68,21 @@ impl TTY {
    /// # Returns
    /// Ok(()) on success, Err(message) on failure
    fn open_pty(&mut self, stream_id: u16) -> Result<(), String> {
        // Open PTY master - must be unsafe
        let master = unsafe { libc::posix_openpt(libc::O_RDWR | libc::O_NOCTTY) };
        if master < 0 {
            return Err("failed to open PTY".to_string());
        }
        // Grant PTY access - unsafe
        if unsafe { libc::grantpt(master) } != 0 {
-            unsafe { libc::close(master); }
+            unsafe { libc::close(master) };
            return Err("failed to grant PTY".to_string());
        }
        // Unlock PTY - unsafe
        if unsafe { libc::unlockpt(master) } != 0 {
-            unsafe { libc::close(master); }
+            unsafe { libc::close(master) };
            return Err("failed to unlock PTY".to_string());
        }
        // Get slave name - unsafe but returns pointer we need to check
        let slave_name = unsafe {
            let ptr = libc::ptsname(master);
            if ptr.is_null() {
@@ -74,26 +92,24 @@ impl TTY {
            std::ffi::CStr::from_ptr(ptr).to_string_lossy().into_owned()
        };
        // Fork - unsafe
        let pid = unsafe { libc::fork() };
        if pid < 0 {
-            unsafe { libc::close(master); }
+            unsafe { libc::close(master) };
            return Err("fork failed".to_string());
        }
        if pid == 0 {
-            // Child process - set up slave PTY and exec shell
+            unsafe { libc::close(master) };
            unsafe { libc::close(master); }
-            let slave = unsafe { libc::open(slave_name.as_ptr() as *const libc::c_char, libc::O_RDWR) };
+            let slave = unsafe {
                libc::open(slave_name.as_ptr() as *const libc::c_char, libc::O_RDWR)
            };
            if slave < 0 {
-                unsafe { libc::exit(1); }
+                unsafe { libc::exit(1) };
            }
-            // Set controlling terminal - unsafe
+            unsafe { libc::ioctl(slave, libc::TIOCSCTTY, 0) };
            unsafe { libc::ioctl(slave, libc::TIOCSCTTY, 0); }
            // Redirect stdio - unsafe
            unsafe {
                libc::dup2(slave, libc::STDIN_FILENO);
                libc::dup2(slave, libc::STDOUT_FILENO);
@@ -101,29 +117,26 @@ impl TTY {
                libc::close(slave);
            }
            // Exec shell - unsafe
            unsafe {
                libc::execl(
                    "/bin/sh\0".as_ptr() as *const libc::c_char,
                    "sh\0".as_ptr() as *const libc::c_char,
-                    std::ptr::null::<libc::c_char>()
+                    std::ptr::null::<libc::c_char>(),
                );
            }
-            // If exec fails, exit
+            unsafe { libc::exit(1) };
            unsafe { libc::exit(1); }
        }
        // Parent - store session
        self.sessions.insert(stream_id, Box::new(PtySession {
            stream_id,
            master,
-            child_pid: pid as u32 
+            child_pid: pid as u32,
        }));
        Ok(())
    }
-    /// Write data to a PTY session
+    /// Write data to a PTY session.
    ///
    /// # Arguments
    /// * `stream_id` - The stream ID
@@ -137,7 +150,7 @@ impl TTY {
            libc::write(
                session.master,
                data.as_ptr() as *const libc::c_void,
-                data.len()
+                data.len(),
            )
        };
        if written < 0 {
@@ -146,28 +159,28 @@ impl TTY {
        Ok(())
    }
-    /// Close a PTY session
+    /// Close a PTY session.
    ///
    /// # Arguments
    /// * `stream_id` - The stream ID to close
    fn close_pty(&mut self, stream_id: u16) {
        if let Some(session) = self.sessions.remove(&stream_id) {
-            // Send SIGTERM to child - unsafe
+            unsafe { libc::kill(session.child_pid as i32, libc::SIGTERM) };
            unsafe { libc::kill(session.child_pid as i32, libc::SIGTERM); }
            // Wait for child - unsafe
            let mut status: libc::c_int = 0;
-            unsafe { libc::waitpid(session.child_pid as i32, &mut status, 0); }
+            unsafe { libc::waitpid(session.child_pid as i32, &mut status, 0) };
-            // Close master - unsafe
+            unsafe { libc::close(session.master) };
            unsafe { libc::close(session.master); }
        }
    }
 }
 impl Endpoint for TTY {
-    /// Handle a request - TTY only supports exec for basic commands
+    fn handle_request(
-    fn handle_request(&mut self, request: &TreeRequest, _src_path: &str) -> Result<TreeResponse, String> {
+        &mut self,
        request: &TreeRequest,
        _src_path: &str,
    ) -> Result<TreeResponse, String> {
        match request {
            TreeRequest::Exec { cmd } => {
                use std::process::{Command, Stdio};
@@ -180,35 +193,38 @@ impl Endpoint for TTY {
                Ok(TreeResponse::ExecOutput {
                    exit_code: output.status.code().unwrap_or(-1),
                    stdout: output.stdout,
-                    stderr: output.stderr 
+                    stderr: output.stderr,
                })
            }
            _ => Err("use stream for TTY".to_string()),
        }
    }
-    /// Handle stream open - creates a new PTY session
+    fn on_stream_open(
-    fn on_stream_open(&mut self, stream_id: u16, _src_path: &str) -> Option<u16> {
+        &mut self,
        stream_id: u16,
        _src_path: &str,
    ) -> Option<u16> {
        self.open_pty(stream_id).ok().map(|_| stream_id)
    }
-    /// Handle stream data - writes to PTY
+    fn on_stream_data(
-    fn on_stream_data(&mut self, stream_id: u16, data: &[u8]) -> bool {
+        &mut self,
        stream_id: u16,
        data: &[u8],
    ) -> bool {
        self.write_to_pty(stream_id, data).ok();
        true
    }
    /// Handle stream close - closes PTY session
    fn on_stream_close(&mut self, stream_id: u16) {
        self.close_pty(stream_id);
    }
    /// Get endpoint type
    fn endpoint_type(&self) -> EndpointType {
        EndpointType::Stream
    }
    /// Get endpoint name
    fn name(&self) -> &str {
        &self.name
    }
@@ -3,20 +3,46 @@
 //! This is a testbed implementation of a tree-based routing protocol for unshell.
 //! It supports serving and connecting to tree endpoints, with leaves for RemoteShell
 //! (command execution) and TTY (PTY streaming).
 //!
 //! # Commands
 //!
 //! - `serve [addr]` - Start a server
 //! - `connect [addr]` - Connect to a server and run CLI
 //! - `run <command>` - Run a single command locally
 //! - (default) - Run interactive CLI with local tree
 //!
 //! # Example
 //!
 //! ```bash
 //! # Start server
 //! $ ush-treetest serve 0.0.0.0:8080
 //!
 //! # Connect from another terminal
 //! $ ush-treetest connect localhost:8080
 //! ```
 mod cli;
 mod client;
 mod leaves;
 mod protocol;
 mod server;
 mod tree;
-use crate::protocol::{FrameHeader, FrameType, TreeRequest, TreeResponse, make_response, make_handshake_ack, Transport};
+use crate::cli::{Cli, parse_and_execute};
 use crate::tree::Tree;
 use crate::leaves::{RemoteShell, TTY};
 use crate::protocol::TcpTransport;
 use std::io::{self, Write};
 use std::sync::{Arc, Mutex};
 use clap::{Parser, Subcommand};
 /// CLI argument parser.
 ///
 /// # Example
 /// ```
 /// let args = Args::parse();
 /// match args.command {
 ///     Some(Command::Serve { addr }) => { ... }
 ///     Some(Command::Connect { addr }) => { ... }
 ///     _ => { ... }
 /// }
 /// ```
 #[derive(Parser)]
 #[command(name = "ush-treetest")]
 #[command(about = "Unshell tree protocol testbed")]
@@ -28,22 +54,49 @@ struct Args {
    addr: Option<String>,
 }
 /// Subcommands for the CLI.
 ///
 /// # Variants
 /// - `Serve` - Start a server
 /// - `Connect` - Connect to a server
 /// - `Run` - Run a single command locally
 /// - `Cli` - Run interactive CLI (default)
 #[derive(Subcommand)]
 enum Command {
    /// Start a server
    Serve {
        /// Address to listen on
        #[arg(default_value = "0.0.0.0:8080")]
        addr: String,
    },
    /// Connect to a server
    Connect {
        /// Server address to connect to
        #[arg(default_value = "localhost:8080")]
        addr: String,
    },
    /// Run interactive CLI
    Cli {},
    /// Run a single command locally
    Run {
        /// Command to execute
        command: String,
    },
 }
 /// Main entry point.
 ///
 /// # Example
 /// ```
 /// // Start server
 /// $ ush-treetest serve
 ///
 /// // Connect to server
 /// $ ush-treetest connect localhost:8080
 ///
 /// // Run locally
 /// $ ush-treetest run "exec /shell echo hello"
 /// ```
 fn main() {
    let _ = env_logger::try_init();
@@ -51,7 +104,7 @@ fn main() {
    match args.command {
        Some(Command::Serve { addr }) => {
-            run_server(&addr);
+            server::run_server(&addr);
        }
        Some(Command::Connect { addr }) => {
            run_client(&addr);
@@ -65,201 +118,12 @@ fn main() {
    }
 }
-fn run_server(addr: &str) {
+/// Run the client with connection to a server.
    log::info!("Starting server on {}", addr);
    let tree = Arc::new(Mutex::new(Tree::new()));
    {
        let mut tree = tree.lock().unwrap();
        tree.add_endpoint("/shell", Box::new(RemoteShell::new("shell")));
        tree.add_endpoint("/tty", Box::new(TTY::new("tty")));
    }
    let listener = TcpTransport::listen(addr).expect("failed to bind");
    log::info!("Listening on {}", addr);
    loop {
        match TcpTransport::accept(&listener) {
            Ok(transport) => {
                log::info!("New connection from {:?}", transport.peer_addr());
                let tree = Arc::clone(&tree);
                std::thread::spawn(move || {
                    handle_connection(transport, tree);
                });
            }
            Err(e) => {
                log::error!("accept error: {:?}", e);
            }
        }
    }
 }
 fn handle_connection(mut transport: TcpTransport, tree: Arc<Mutex<Tree>>) {
    let (header, _payload) = match transport.recv_frame() {
        Ok(h) => h,
        Err(e) => {
            log::error!("recv error: {:?}", e);
            return;
        }
    };
    if header.frame_type != FrameType::Handshake {
        log::error!("expected handshake");
        return;
    }
    log::info!("Client connected");
    let (ack_header, ack_payload) = make_handshake_ack(true, "/client");
    transport.send_frame(&ack_header, Some(&ack_payload)).expect("send failed");
    loop {
        match transport.recv_frame() {
            Ok((header, payload)) => {
                let response = handle_frame(&header, &payload, &tree);
                if let Some(response) = response {
                    let (resp_header, resp_payload) = match response {
                        Ok((h, p)) => (h, p),
                        Err(e) => {
                            log::error!("handle error: {:?}", e);
                            break;
                        }
                    };
                    transport.send_frame(&resp_header, Some(&resp_payload)).expect("send failed");
                }
                if header.frame_type == FrameType::StreamClose {
                    break;
                }
            }
            Err(e) => {
                log::error!("recv error: {:?}", e);
                break;
            }
        }
    }
    log::info!("Connection closed");
 }
 /// Handle a single frame and return an optional response
 ///
 /// # Arguments
-/// * `header` - The frame header
+/// * `addr` - Server address
 /// * `payload` - The frame payload bytes
 /// * `tree` - Shared access to the tree
 /// 
 /// # Returns
 /// Some(Ok((header, payload))) for a response to send, Some(Err(e)) for an error, None for no response
 fn handle_frame(header: &FrameHeader, payload: &[u8], tree: &Arc<Mutex<Tree>>) -> Option<Result<(FrameHeader, Vec<u8>), String>> {
    match header.frame_type {
        FrameType::Request => {
            let request: TreeRequest = match TreeRequest::from_bytes(payload) {
                Ok(r) => r,
                Err(e) => return Some(Err(e.to_string())),
            };
            let dst_path = header.dst_path.as_deref().unwrap_or("/");
            // Acquire lock for the entire request handling
            let mut tree = match tree.lock() {
                Ok(t) => t,
                Err(e) => return Some(Err(format!("lock error: {}", e))),
            };
            let response = match request {
                TreeRequest::ListNodes {} => {
                    let names = tree.list_nodes(dst_path).unwrap_or_default();
                    TreeResponse::NodeList { names }
                }
                TreeRequest::ListEndpoints {} => {
                    let endpoints = tree.list_endpoints(dst_path).unwrap_or_default();
                    TreeResponse::EndpointList { endpoints }
                }
                TreeRequest::ListLeaves {} => {
                    let leaves = tree.list_leaves();
                    TreeResponse::LeafList { leaves }
                }
                TreeRequest::GetInfo { path } => {
                    match tree.get_info(&path) {
                        Ok(info) => TreeResponse::NodeInfo { info },
                        Err(e) => return Some(Err(e)),
                    }
                }
                TreeRequest::Exec { ref cmd } => {
                    let (handler, matched_path) = match tree.find_handler(dst_path) {
                        Some(h) => h,
                        None => return Some(Err(format!("path not found: {}", dst_path))),
                    };
                    // Lock the handler and make the request
                    let result = {
                        let mut handler = match handler.lock() {
                            Ok(h) => h,
                            Err(e) => return Some(Err(format!("lock error: {}", e))),
                        };
                        handler.handle_request(&TreeRequest::Exec { cmd: cmd.clone() }, matched_path)
                    };
                    match result {
                        Ok(resp) => resp,
                        Err(e) => return Some(Err(e)),
                    }
                }
                TreeRequest::StreamOpen { path } => {
                    match tree.open_stream(&path, &header.src_path) {
                        Ok(stream_id) => TreeResponse::StreamOpened { stream_id },
                        Err(e) => return Some(Err(e)),
                    }
                }
                TreeRequest::Resize { .. } => {
                    return Some(Err("unsupported request: Resize".to_string()));
                }
            };
            Some(Ok(make_response(&header.src_path, header.request_id.unwrap_or(0), &response)))
        }
        FrameType::StreamOpen => {
            let dst_path = header.dst_path.as_deref().unwrap_or("/");
            let mut tree = match tree.lock() {
                Ok(t) => t,
                Err(e) => return Some(Err(format!("lock error: {}", e))),
            };
            match tree.open_stream(dst_path, &header.src_path) {
                Ok(stream_id) => {
                    let response = TreeResponse::StreamOpened { stream_id };
                    Some(Ok(make_response(&header.src_path, header.request_id.unwrap_or(0), &response)))
                }
                Err(e) => Some(Err(e)),
            }
        }
        FrameType::StreamData => {
            let mut tree = match tree.lock() {
                Ok(t) => t,
                Err(e) => return Some(Err(format!("lock error: {}", e))),
            };
            tree.route_stream_data(header, payload).ok();
            None
        }
        FrameType::StreamClose => {
            let mut tree = match tree.lock() {
                Ok(t) => t,
                Err(e) => return Some(Err(format!("lock error: {}", e))),
            };
            if let Some(stream_id) = header.stream_id {
                tree.close_stream(stream_id).ok();
            }
            None
        }
        _ => Some(Err("unsupported frame type".to_string())),
    }
 }
 fn run_client(addr: &str) {
-    let mut cli = cli::Cli::new();
+    let mut cli = Cli::new();
    if let Err(e) = cli.connect(addr) {
        eprintln!("Failed to connect: {}", e);
@@ -270,8 +134,9 @@ fn run_client(addr: &str) {
    run_cli_loop(&mut cli);
 }
 /// Run an interactive CLI with a local tree.
 fn run_interactive() {
-    let mut cli = cli::Cli::new();
+    let mut cli = Cli::new();
    println!("Unshell Tree Protocol Testbed");
    println!("Type 'help' for commands\n");
@@ -284,7 +149,11 @@ fn run_interactive() {
    run_cli_loop(&mut cli);
 }
-fn run_cli_loop(cli: &mut cli::Cli) {
+/// Run the CLI command loop.
 ///
 /// # Arguments
 /// * `cli` - The CLI instance
 fn run_cli_loop(cli: &mut Cli) {
    loop {
        print!("{}> ", cli.current_path());
        io::stdout().flush().ok();
@@ -304,7 +173,7 @@ fn run_cli_loop(cli: &mut cli::Cli) {
            break;
        }
-        match cli::parse_and_execute(cli, line) {
+        match parse_and_execute(cli, line) {
            Ok(output) => {
                if !output.is_empty() {
                    println!("{}", output);
@@ -317,10 +186,14 @@ fn run_cli_loop(cli: &mut cli::Cli) {
    }
 }
 /// Run a single command locally.
 ///
 /// # Arguments
 /// * `command` - The command to run
 fn run_single_command(command: &str) {
-    let mut cli = cli::Cli::new();
+    let mut cli = Cli::new();
-    match cli::parse_and_execute(&mut cli, command) {
+    match parse_and_execute(&mut cli, command) {
        Ok(output) => {
            if !output.is_empty() {
                println!("{}", output);
@@ -1,4 +1,42 @@
 //! # Protocol Module
 //!
 //! This module defines the protocol types and transport layer for the unshell tree protocol.
 //! It provides serialization via rkyv and TCP transport for frame passing.
 //!
 //! # Frame Format
 //!
 //! Each frame consists of:
 //! - 4-byte header length (little-endian u32)
 //! - Serialized header bytes (using rkyv)
 //! - 4-byte payload length (little-endian u32)
 //! - Payload bytes (optional)
 //!
 //! # Usage
 //!
 //! ```no_run
 //! use ush_treetest::protocol::{
 //!     FrameType, FrameHeader, TreeRequest, TreeResponse,
 //!     TcpTransport, Transport,
 //! };
 //!
 //! // Connect to server
 //! let mut transport = TcpTransport::connect("localhost:8080").unwrap();
 //!
 //! // Send a request
 //! let header = FrameHeader {
 //!     frame_type: FrameType::Request,
 //!     dst_path: Some("/shell".to_string()),
 //!     src_path: "/client".to_string(),
 //!     request_id: Some(1),
 //!     stream_id: None,
 //! };
 //! let payload = TreeRequest::Exec { cmd: "echo hello".to_string() }.to_bytes();
 //! transport.send_frame(&header, Some(&payload)).unwrap();
 //!
 //! // Receive response
 //! let (header, payload) = transport.recv_frame().unwrap();
 //! let response = TreeResponse::from_bytes(&payload).unwrap();
 //! ```
 pub mod types;
 pub mod transport;
@@ -1,27 +1,85 @@
 //! # Transport Layer
 //!
 //! This module provides the Transport trait and TCP implementation.
-//! Uses a simple length-prefixed framing: [u32 header_len][header bytes][u32 payload_len][payload bytes]
+//! Uses a simple length-prefixed framing: `[u32 header_len][header bytes][u32 payload_len][payload bytes]`
 //!
 //! # Frame Format
 //!
 //! Each frame is encoded as:
 //! - 4 bytes: header length (little-endian u32)
 //! - N bytes: serialized header
 //! - 4 bytes: payload length (little-endian u32)
 //! - M bytes: payload (optional)
 //!
 //! # Usage
 //!
 //! ```no_run
 //! use ush_treetest::protocol::{TcpTransport, Transport, FrameHeader, FrameType};
 //!
 //! // Connect to server
 //! let mut transport = TcpTransport::connect("localhost:8080").unwrap();
 //!
 //! // Send a frame
 //! let header = FrameHeader {
 //!     frame_type: FrameType::Request,
 //!     dst_path: Some("/shell".to_string()),
 //!     src_path: "/client".to_string(),
 //!     request_id: Some(1),
 //!     stream_id: None,
 //! };
 //! transport.send_frame(&header, Some(b"test payload")).unwrap();
 //!
 //! // Receive a frame
 //! let (header, payload) = transport.recv_frame().unwrap();
 //! ```
 use crate::protocol::types::*;
 use std::net::{TcpStream, TcpListener};
 use std::io::{Read, Write, Error};
 /// Transport trait - interface for sending and receiving frames.
 ///
 /// This trait defines the interface for all transport implementations.
 /// Implementors must provide send_frame, recv_frame, and close methods.
 pub trait Transport: Sized {
    /// Error type for this transport
    type Error: std::fmt::Debug;
-    /// Send a frame (header + optional payload)
+
-    fn send_frame(&mut self, header: &FrameHeader, payload: Option<&[u8]>) -> Result<(), Self::Error>;
+    /// Send a frame (header + optional payload).
-    /// Receive a frame
+    ///
    /// # Arguments
    /// * `header` - The frame header
    /// * `payload` - Optional payload bytes
    fn send_frame(
        &mut self,
        header: &FrameHeader,
        payload: Option<&[u8]>,
    ) -> Result<(), Self::Error>;
    /// Receive a frame.
    ///
    /// # Returns
    /// (header, payload) tuple
    fn recv_frame(&mut self) -> Result<(FrameHeader, Vec<u8>), Self::Error>;
-    /// Close the transport
+
    /// Close the transport.
    #[allow(dead_code)]
    fn close(&mut self) -> Result<(), Self::Error>;
 }
 /// Transport-level errors.
 ///
 /// # Variants
 /// * `ConnectionClosed` - The connection was closed
 /// * `InvalidFrame` - The frame was invalid
 /// * `Io` - I/O error
 #[derive(Debug)]
 pub enum TransportError {
    /// Connection was closed
    ConnectionClosed,
    /// Invalid frame format
    InvalidFrame(String),
    /// I/O error
    Io(String),
 }
@@ -36,52 +94,106 @@ impl std::fmt::Display for TransportError {
 }
 impl From<Error> for TransportError {
-    fn from(e: Error) -> Self { TransportError::Io(e.to_string()) }
+    fn from(e: Error) -> Self {
        TransportError::Io(e.to_string())
    }
 }
-/// TCP transport implementation
+/// TCP transport implementation.
 #[derive(Debug)]
 pub struct TcpTransport {
    stream: TcpStream,
 }
 impl TcpTransport {
    /// Create a new TCP transport from an existing stream.
    ///
    /// Sets read/write timeouts to 30 seconds for safety.
    ///
    /// # Arguments
    /// * `stream` - An existing TCP stream
    pub fn new(stream: TcpStream) -> Self {
-        // Set timeouts for safety
+        stream
-        stream.set_read_timeout(Some(std::time::Duration::from_secs(30))).ok();
+            .set_read_timeout(Some(std::time::Duration::from_secs(30)))
-        stream.set_write_timeout(Some(std::time::Duration::from_secs(30))).ok();
+            .ok();
        stream
            .set_write_timeout(Some(std::time::Duration::from_secs(30)))
            .ok();
        Self { stream }
    }
-    /// Connect to a remote address
+    /// Connect to a remote address.
    ///
    /// # Arguments
    /// * `addr` - The address to connect to (e.g., "localhost:8080")
    ///
    /// # Returns
    /// Connected transport
    ///
    /// # Example
    /// ```
    /// let transport = TcpTransport::connect("localhost:8080").unwrap();
    /// ```
    pub fn connect(addr: &str) -> Result<Self, TransportError> {
        let stream = TcpStream::connect(addr)?;
        Ok(Self::new(stream))
    }
-    /// Create a listening socket
+    /// Create a listening socket.
    ///
    /// # Arguments
    /// * `addr` - The address to listen on
    ///
    /// # Returns
    /// TCP listener
    ///
    /// # Example
    /// ```
    /// let listener = TcpTransport::listen("0.0.0.0:8080").unwrap();
    /// ```
    pub fn listen(addr: &str) -> Result<std::net::TcpListener, TransportError> {
        let listener = TcpListener::bind(addr)?;
        listener.set_nonblocking(false)?;
        Ok(listener)
    }
-    /// Accept an incoming connection
+    /// Accept an incoming connection.
    ///
    /// # Arguments
    /// * `listener` - The listening socket
    ///
    /// # Returns
    /// New transport for the connection
    ///
    /// # Example
    /// ```
    /// let listener = TcpTransport::listen("0.0.0.0:8080").unwrap();
    /// let transport = TcpTransport::accept(&listener).unwrap();
    /// ```
    pub fn accept(listener: &std::net::TcpListener) -> Result<Self, TransportError> {
        let stream = listener.accept()?.0;
        Ok(Self::new(stream))
    }
-    /// Get peer address
+    /// Get peer address.
    ///
    /// # Returns
    /// The peer's socket address
    pub fn peer_addr(&self) -> Result<std::net::SocketAddr, std::io::Error> {
        self.stream.peer_addr()
    }
-    /// Read exactly n bytes
+    /// Read exactly n bytes.
    ///
    /// Will block until all bytes are read or an error occurs.
    fn read_exact(&mut self, mut n: usize) -> Result<Vec<u8>, TransportError> {
        let mut buf = Vec::with_capacity(n);
        while n > 0 {
            let mut chunk = vec![0u8; n];
-            let read = self.stream.read(&mut chunk).map_err(|e| TransportError::Io(e.to_string()))?;
+            let read =
                self.stream
                    .read(&mut chunk)
                    .map_err(|e| TransportError::Io(e.to_string()))?;
            if read == 0 {
                return Err(TransportError::ConnectionClosed);
            }
@@ -95,41 +207,45 @@ impl TcpTransport {
 impl Transport for TcpTransport {
    type Error = TransportError;
-    fn send_frame(&mut self, header: &FrameHeader, payload: Option<&[u8]>) -> Result<(), Self::Error> {
+    fn send_frame(
-        // Serialize header using rkyv
+        &mut self,
        header: &FrameHeader,
        payload: Option<&[u8]>,
    ) -> Result<(), Self::Error> {
        let header_bytes = header.to_bytes();
        let header_len = header_bytes.len() as u32;
        // Get payload bytes
        let payload_bytes = payload.unwrap_or(&[]);
        let payload_len = payload_bytes.len() as u32;
-        // Build frame: [u32 header_len][header][u32 payload_len][payload]
+        let mut frame =
-        let mut frame = Vec::with_capacity(4 + header_len as usize + 4 + payload_len as usize);
+            Vec::with_capacity(4 + header_len as usize + 4 + payload_len as usize);
        frame.extend_from_slice(&header_len.to_le_bytes());
        frame.extend_from_slice(&header_bytes);
        frame.extend_from_slice(&payload_len.to_le_bytes());
        frame.extend_from_slice(payload_bytes);
-        self.stream.write_all(&frame).map_err(|e| TransportError::Io(e.to_string()))?;
+        self.stream
-        self.stream.flush().map_err(|e| TransportError::Io(e.to_string()))?;
+            .write_all(&frame)
            .map_err(|e| TransportError::Io(e.to_string()))?;
        self.stream
            .flush()
            .map_err(|e| TransportError::Io(e.to_string()))?;
        Ok(())
    }
    fn recv_frame(&mut self) -> Result<(FrameHeader, Vec<u8>), Self::Error> {
        // Read header length
        let header_len_bytes = self.read_exact(4)?;
        let header_len = u32::from_le_bytes(header_len_bytes.try_into().unwrap()) as usize;
        // Read header
        let header_bytes = self.read_exact(header_len)?;
-        let header = FrameHeader::from_bytes(&header_bytes).map_err(|e| TransportError::InvalidFrame(e))?;
+        let header =
            FrameHeader::from_bytes(&header_bytes).map_err(|e| TransportError::InvalidFrame(e))?;
        // Read payload length
        let payload_len_bytes = self.read_exact(4)?;
-        let payload_len = u32::from_le_bytes(payload_len_bytes.try_into().unwrap()) as usize;
+        let payload_len =
            u32::from_le_bytes(payload_len_bytes.try_into().unwrap()) as usize;
        // Read payload
        let payload = if payload_len > 0 {
            self.read_exact(payload_len)?
        } else {
@@ -140,17 +256,37 @@ impl Transport for TcpTransport {
    }
    fn close(&mut self) -> Result<(), Self::Error> {
-        self.stream.shutdown(std::net::Shutdown::Both).map_err(|e| TransportError::Io(e.to_string()))?;
+        self.stream
            .shutdown(std::net::Shutdown::Both)
            .map_err(|e| TransportError::Io(e.to_string()))?;
        Ok(())
    }
 }
-// =============================================================================
+/// Create a request frame.
-// Frame builder functions
+///
-// =============================================================================
+/// # Arguments
-
+/// * `dst_path` - Destination path
-/// Create a request frame
+/// * `src_path` - Source path
-pub fn make_request(dst_path: &str, src_path: &str, request_id: u64, request: &TreeRequest) -> (FrameHeader, Vec<u8>) {
+/// * `request_id` - Request ID
 /// * `request` - The request payload
 ///
 /// # Returns
 /// (header, payload) tuple
 ///
 /// # Example
 /// ```
 /// use ush_treetest::protocol::{make_request, TreeRequest};
 ///
 /// let request = TreeRequest::Exec { cmd: "echo hello".to_string() };
 /// let (header, payload) = make_request("/shell", "/client", 1, &request);
 /// ```
 pub fn make_request(
    dst_path: &str,
    src_path: &str,
    request_id: u64,
    request: &TreeRequest,
 ) -> (FrameHeader, Vec<u8>) {
    let header = FrameHeader {
        frame_type: FrameType::Request,
        dst_path: Some(dst_path.to_string()),
@@ -162,8 +298,20 @@ pub fn make_request(dst_path: &str, src_path: &str, request_id: u64, request: &T
    (header, payload)
 }
-/// Create a response frame  
+/// Create a response frame.
-pub fn make_response(src_path: &str, request_id: u64, response: &TreeResponse) -> (FrameHeader, Vec<u8>) {
+///
 /// # Arguments
 /// * `src_path` - Source path
 /// * `request_id` - Request ID
 /// * `response` - The response payload
 ///
 /// # Returns
 /// (header, payload) tuple
 pub fn make_response(
    src_path: &str,
    request_id: u64,
    response: &TreeResponse,
 ) -> (FrameHeader, Vec<u8>) {
    let header = FrameHeader {
        frame_type: FrameType::Response,
        dst_path: None,
@@ -175,7 +323,15 @@ pub fn make_response(src_path: &str, request_id: u64, response: &TreeResponse) -
    (header, payload)
 }
-/// Create a stream open frame
+/// Create a stream open frame.
 ///
 /// # Arguments
 /// * `dst_path` - Destination path
 /// * `src_path` - Source path
 /// * `request_id` - Request ID
 ///
 /// # Returns
 /// Frame header (no payload)
 pub fn make_stream_open(dst_path: &str, src_path: &str, request_id: u64) -> FrameHeader {
    FrameHeader {
        frame_type: FrameType::StreamOpen,
@@ -186,7 +342,14 @@ pub fn make_stream_open(dst_path: &str, src_path: &str, request_id: u64) -> Fram
    }
 }
-/// Create a stream data frame
+/// Create a stream data frame.
 ///
 /// # Arguments
 /// * `stream_id` - Stream ID
 /// * `data` - Data to send
 ///
 /// # Returns
 /// (header, payload) tuple
 pub fn make_stream_data(stream_id: u16, data: &[u8]) -> (FrameHeader, Vec<u8>) {
    let header = FrameHeader {
        frame_type: FrameType::StreamData,
@@ -198,7 +361,13 @@ pub fn make_stream_data(stream_id: u16, data: &[u8]) -> (FrameHeader, Vec<u8>) {
    (header, data.to_vec())
 }
-/// Create a stream close frame
+/// Create a stream close frame.
 ///
 /// # Arguments
 /// * `stream_id` - Stream ID to close
 ///
 /// # Returns
 /// Frame header (no payload)
 pub fn make_stream_close(stream_id: u16) -> FrameHeader {
    FrameHeader {
        frame_type: FrameType::StreamClose,
@@ -209,9 +378,25 @@ pub fn make_stream_close(stream_id: u16) -> FrameHeader {
    }
 }
-/// Create a handshake frame
+/// Create a handshake frame.
 ///
 /// # Arguments
 /// * `registered_paths` - Paths to register
 ///
 /// # Returns
 /// (header, payload) tuple
 ///
 /// # Example
 /// ```
 /// use ush_treetest::protocol::make_handshake;
 ///
 /// let paths = vec!["/client".to_string()];
 /// let (header, payload) = make_handshake(paths);
 /// ```
 pub fn make_handshake(registered_paths: Vec<String>) -> (FrameHeader, Vec<u8>) {
-    let handshake = Handshake { registered_paths };
+    let handshake = Handshake {
        registered_paths,
    };
    let payload = handshake.to_bytes();
    let header = FrameHeader {
        frame_type: FrameType::Handshake,
@@ -223,11 +408,21 @@ pub fn make_handshake(registered_paths: Vec<String>) -> (FrameHeader, Vec<u8>) {
    (header, payload)
 }
-/// Create a handshake ack frame
+/// Create a handshake ack frame.
-pub fn make_handshake_ack(accepted: bool, assigned_base_path: &str) -> (FrameHeader, Vec<u8>) {
+///
 /// # Arguments
 /// * `accepted` - Whether handshake was accepted
 /// * `assigned_base_path` - Base path to assign
 ///
 /// # Returns
 /// (header, payload) tuple
 pub fn make_handshake_ack(
    accepted: bool,
    assigned_base_path: &str,
 ) -> (FrameHeader, Vec<u8>) {
    let ack = HandshakeAck {
        accepted,
-        assigned_base_path: assigned_base_path.to_string() 
+        assigned_base_path: assigned_base_path.to_string(),
    };
    let payload = ack.to_bytes();
    let header = FrameHeader {
@@ -2,27 +2,86 @@
 //!
 //! This module defines the core types for the UnShell protocol.
 //! Uses rkyv for zero-copy serialization.
 //!
 //! # Serialization
 //!
 //! All types implement `rkyv::Archive`, `rkyv::Serialize`, and `rkyv::Deserialize`
 //! for efficient serialization without runtime type information.
 //!
 //! # Example
 //!
 //! ```no_run
 //! use ush_treetest::protocol::{TreeRequest, TreeResponse};
 //!
 //! // Serialize a request
 //! let request = TreeRequest::Exec { cmd: "echo hello".to_string() };
 //! let bytes = request.to_bytes();
 //!
 //! // Deserialize it back
 //! let decoded = TreeRequest::from_bytes(&bytes).unwrap();
 //! ```
 use rkyv::{Archive, Serialize, Deserialize};
 use std::string::String;
 use std::vec::Vec;
 /// Default buffer size for rkyv serialization.
 ///
 /// This value is chosen to accommodate typical protocol messages.
 const BUFFER_SIZE: usize = 4096;
-/// Frame type enum - distinguishes between different frame kinds
+/// Frame type enum - distinguishes between different frame kinds.
 ///
 /// Each frame type has a specific purpose in the protocol:
 /// - `Request` / `Response`: Request-response pairs
 /// - `StreamOpen` / `StreamData` / `StreamClose`: Streaming operations
 /// - `Handshake` / `HandshakeAck`: Connection setup
 ///
 /// # Example
 /// ```
 /// use ush_treetest::protocol::FrameType;
 ///
 /// let frame_type = FrameType::Request;
 /// assert_eq!(frame_type as u8, 0x01);
 /// ```
 #[derive(Archive, Serialize, Deserialize, Debug, Clone, Copy, PartialEq, Eq)]
 #[repr(u8)]
 pub enum FrameType {
    /// Request frame - client requesting an operation
    Request = 0x01,
    /// Response frame - server responding to a request
    Response = 0x02,
    /// Stream open frame - requesting a stream
    StreamOpen = 0x03,
    /// Stream data frame - sending data on a stream
    StreamData = 0x04,
    /// Stream close frame - closing a stream
    StreamClose = 0x05,
    /// Handshake frame - connection initialization
    Handshake = 0x10,
    /// Handshake acknowledgement - connection acceptance
    HandshakeAck = 0x11,
 }
 impl FrameType {
    /// Convert a byte value to a FrameType.
    ///
    /// # Arguments
    /// * `v` - The byte value to convert
    ///
    /// # Returns
    /// Some(FrameType) if valid, None otherwise
    ///
    /// # Example
    /// ```
    /// use ush_treetest::protocol::FrameType;
    ///
    /// let ft = FrameType::from_u8(0x01);
    /// assert_eq!(ft, Some(FrameType::Request));
    ///
    /// let invalid = FrameType::from_u8(0xFF);
    /// assert_eq!(invalid, None);
    /// ```
    #[allow(dead_code)]
    pub fn from_u8(v: u8) -> Option<Self> {
        match v {
@@ -38,124 +97,323 @@ impl FrameType {
    }
 }
-/// Frame header - the metadata sent before each payload
+/// Frame header - the metadata sent before each payload.
 ///
 /// The header contains routing information and identifies the frame type.
 ///
 /// # Fields
 /// * `frame_type` - The type of frame
 /// * `dst_path` - Optional destination path for routing
 /// * `src_path` - Source path for the frame
 /// * `request_id` - Optional request ID for correlation
 /// * `stream_id` - Optional stream ID for streaming
 ///
 /// # Example
 /// ```
 /// use ush_treetest::protocol::{FrameHeader, FrameType};
 ///
 /// let header = FrameHeader {
 ///     frame_type: FrameType::Request,
 ///     dst_path: Some("/shell".to_string()),
 ///     src_path: "/client".to_string(),
 ///     request_id: Some(1),
 ///     stream_id: None,
 /// };
 ///
 /// // Serialize and deserialize
 /// let bytes = header.to_bytes();
 /// let decoded = FrameHeader::from_bytes(&bytes).unwrap();
 /// assert_eq!(decoded.frame_type, FrameType::Request);
 /// ```
 #[derive(Archive, Serialize, Deserialize, Debug, Clone)]
 pub struct FrameHeader {
    /// The type of this frame
    pub frame_type: FrameType,
    /// Destination path for routing (None for responses)
    pub dst_path: Option<String>,
    /// Source path of the sender
    pub src_path: String,
    /// Request ID for correlation (for request/response)
    pub request_id: Option<u64>,
    /// Stream ID (for stream operations)
    pub stream_id: Option<u16>,
 }
 impl FrameHeader {
    /// Serialize the header to bytes.
    ///
    /// # Returns
    /// Serialized bytes
    pub fn to_bytes(&self) -> Vec<u8> {
-        rkyv::to_bytes::<FrameHeader, BUFFER_SIZE>(self).unwrap().into_vec()
+        rkyv::to_bytes::<FrameHeader, BUFFER_SIZE>(self)
            .unwrap()
            .into_vec()
    }
    /// Deserialize header from bytes.
    ///
    /// # Arguments
    /// * `bytes` - Serialized bytes
    ///
    /// # Returns
    /// Deserialized header
    pub fn from_bytes(bytes: &[u8]) -> Result<Self, String> {
        unsafe { rkyv::from_bytes_unchecked(bytes) }.map_err(|e| e.to_string())
    }
 }
-/// Tree request - operations on the tree
+/// Tree request - operations on the tree.
 ///
 /// These requests are sent from clients to servers to perform operations.
 ///
 /// # Example
 /// ```
 /// use ush_treetest::protocol::TreeRequest;
 ///
 /// // Execute a command
 /// let request = TreeRequest::Exec { cmd: "echo hello".to_string() };
 /// let bytes = request.to_bytes();
 /// let decoded = TreeRequest::from_bytes(&bytes).unwrap();
 /// ```
 #[derive(Archive, Serialize, Deserialize, Debug, Clone)]
 pub enum TreeRequest {
    /// List child nodes at a path
    ListNodes {},
    /// List endpoints at a path
    ListEndpoints {},
    /// List all leaf paths in the tree
    ListLeaves {},
    /// Get information about a node
    GetInfo { path: String },
    /// Execute a command
    Exec { cmd: String },
    /// Open a stream to a path
    StreamOpen { path: String },
    /// Resize a terminal
    Resize { rows: u16, cols: u16 },
 }
 impl TreeRequest {
    /// Serialize the request to bytes.
    pub fn to_bytes(&self) -> Vec<u8> {
-        rkyv::to_bytes::<TreeRequest, BUFFER_SIZE>(self).unwrap().into_vec()
+        rkyv::to_bytes::<TreeRequest, BUFFER_SIZE>(self)
            .unwrap()
            .into_vec()
    }
    /// Deserialize request from bytes.
    ///
    /// # Arguments
    /// * `bytes` - Serialized bytes
    pub fn from_bytes(bytes: &[u8]) -> Result<Self, String> {
        unsafe { rkyv::from_bytes_unchecked(bytes) }.map_err(|e| e.to_string())
    }
 }
-/// Tree response - results from tree operations
+/// Tree response - results from tree operations.
 ///
 /// These responses are sent from servers to clients.
 ///
 /// # Example
 /// ```
 /// use ush_treetest::protocol::TreeResponse;
 ///
 /// let response = TreeResponse::ExecOutput {
 ///     exit_code: 0,
 ///     stdout: b"hello".to_vec(),
 ///     stderr: b"".to_vec(),
 /// };
 /// let bytes = response.to_bytes();
 /// ```
 #[derive(Archive, Serialize, Deserialize, Debug, Clone)]
 pub enum TreeResponse {
    /// List of child node names
    NodeList { names: Vec<String> },
    /// List of endpoints
    EndpointList { endpoints: Vec<EndpointInfo> },
    /// List of leaf paths
    LeafList { leaves: Vec<String> },
    /// Node information
    NodeInfo { info: NodeInfo },
-    ExecOutput { exit_code: i32, stdout: Vec<u8>, stderr: Vec<u8> },
+    /// Command execution output
    ExecOutput {
        exit_code: i32,
        stdout: Vec<u8>,
        stderr: Vec<u8>,
    },
    /// Stream opened confirmation
    StreamOpened { stream_id: u16 },
 }
 impl TreeResponse {
    /// Serialize the response to bytes.
    pub fn to_bytes(&self) -> Vec<u8> {
-        rkyv::to_bytes::<TreeResponse, BUFFER_SIZE>(self).unwrap().into_vec()
+        rkyv::to_bytes::<TreeResponse, BUFFER_SIZE>(self)
            .unwrap()
            .into_vec()
    }
    /// Deserialize response from bytes.
    ///
    /// # Arguments
    /// * `bytes` - Serialized bytes
    pub fn from_bytes(bytes: &[u8]) -> Result<Self, String> {
        unsafe { rkyv::from_bytes_unchecked(bytes) }.map_err(|e| e.to_string())
    }
 }
-/// Information about an endpoint
+/// Information about an endpoint.
 ///
 /// # Fields
 /// * `name` - The endpoint name
 /// * `path` - The path where the endpoint is registered
 /// * `endpoint_type` - The type of endpoint
 ///
 /// # Example
 /// ```
 /// use ush_treetest::protocol::{EndpointInfo, EndpointType};
 ///
 /// let info = EndpointInfo {
 ///     name: "shell".to_string(),
 ///     path: "/shell".to_string(),
 ///     endpoint_type: EndpointType::Leaf,
 /// };
 /// ```
 #[derive(Archive, Serialize, Deserialize, Debug, Clone)]
 pub struct EndpointInfo {
    /// The endpoint name
    pub name: String,
    /// The path where this endpoint is registered
    pub path: String,
    /// The type of this endpoint
    pub endpoint_type: EndpointType,
 }
-/// Type of endpoint
+/// Type of endpoint.
 ///
 /// # Example
 /// ```
 /// use ush_treetest::protocol::EndpointType;
 ///
 /// let leaf_type = EndpointType::Leaf;
 /// assert!(matches!(leaf_type, EndpointType::Leaf));
 /// ```
 #[derive(Archive, Serialize, Deserialize, Debug, Clone, Copy)]
 #[repr(u8)]
 pub enum EndpointType {
    /// Leaf endpoint - executes commands
    Leaf = 0x01,
    /// Proxy endpoint - routes to other endpoints
    Proxy = 0x02,
    /// Stream endpoint - provides streaming
    Stream = 0x03,
 }
-/// Information about a node in the tree
+/// Information about a node in the tree.
 ///
 /// # Fields
 /// * `path` - The node path
 /// * `is_leaf` - Whether this is a leaf node
 /// * `has_children` - Whether this node has children
 /// * `endpoints` - List of endpoint names at this node
 ///
 /// # Example
 /// ```
 /// use ush_treetest::protocol::NodeInfo;
 ///
 /// let info = NodeInfo {
 ///     path: "/shell".to_string(),
 ///     is_leaf: true,
 ///     has_children: false,
 ///     endpoints: vec!["shell".to_string()],
 /// };
 /// assert!(info.is_leaf);
 /// ```
 #[derive(Archive, Serialize, Deserialize, Debug, Clone)]
 pub struct NodeInfo {
    /// The node path
    pub path: String,
    /// Whether this is a leaf node (endpoint with no children)
    pub is_leaf: bool,
    /// Whether this node has children
    pub has_children: bool,
    /// Names of endpoints at this node
    pub endpoints: Vec<String>,
 }
-/// Handshake message - sent when connecting
+/// Handshake message - sent when connecting.
 ///
 /// The client sends registered paths during handshake.
 ///
 /// # Fields
 /// * `registered_paths` - Paths the client wants to register
 ///
 /// # Example
 /// ```
 /// use ush_treetest::protocol::Handshake;
 ///
 /// let handshake = Handshake {
 ///     registered_paths: vec!["/client".to_string()],
 /// };
 /// let bytes = handshake.to_bytes();
 /// ```
 #[derive(Archive, Serialize, Deserialize, Debug, Clone)]
 pub struct Handshake {
    /// Paths the client wants to register
    pub registered_paths: Vec<String>,
 }
 impl Handshake {
    /// Serialize the handshake to bytes.
    pub fn to_bytes(&self) -> Vec<u8> {
-        rkyv::to_bytes::<Handshake, BUFFER_SIZE>(self).unwrap().into_vec()
+        rkyv::to_bytes::<Handshake, BUFFER_SIZE>(self)
            .unwrap()
            .into_vec()
    }
    /// Deserialize handshake from bytes.
    #[allow(dead_code)]
    pub fn from_bytes(bytes: &[u8]) -> Result<Self, String> {
        unsafe { rkyv::from_bytes_unchecked(bytes) }.map_err(|e| e.to_string())
    }
 }
-/// Handshake acknowledgement - router's response to handshake
+/// Handshake acknowledgement - router's response to handshake.
 ///
 /// # Fields
 /// * `accepted` - Whether the handshake was accepted
 /// * `assigned_base_path` - Base path assigned by the server
 ///
 /// # Example
 /// ```
 /// use ush_treetest::protocol::HandshakeAck;
 ///
 /// let ack = HandshakeAck {
 ///     accepted: true,
 ///     assigned_base_path: "/client".to_string(),
 /// };
 /// assert!(ack.accepted);
 /// ```
 #[derive(Archive, Serialize, Deserialize, Debug, Clone)]
 pub struct HandshakeAck {
    /// Whether the handshake was accepted
    pub accepted: bool,
    /// Base path assigned by the server
    pub assigned_base_path: String,
 }
 impl HandshakeAck {
    /// Serialize the acknowledgement to bytes.
    pub fn to_bytes(&self) -> Vec<u8> {
-        rkyv::to_bytes::<HandshakeAck, BUFFER_SIZE>(self).unwrap().into_vec()
+        rkyv::to_bytes::<HandshakeAck, BUFFER_SIZE>(self)
            .unwrap()
            .into_vec()
    }
    /// Deserialize acknowledgement from bytes.
    ///
    /// # Arguments
    /// * `bytes` - Serialized bytes
    pub fn from_bytes(bytes: &[u8]) -> Result<Self, String> {
        unsafe { rkyv::from_bytes_unchecked(bytes) }.map_err(|e| e.to_string())
    }
@@ -0,0 +1,264 @@
 //! # Server Implementation
 //!
 //! This module provides the server functionality for handling incoming connections.
 use crate::protocol::{
    FrameHeader, FrameType, TreeRequest, TreeResponse, TcpTransport, Transport,
    make_response, make_handshake_ack,
 };
 use crate::tree::Tree;
 use crate::leaves::{RemoteShell, TTY};
 use std::sync::{Arc, Mutex};
 /// Default listening address for the server.
 ///
 /// # Example
 /// ```
 /// let addr = ush_treetest::server::DEFAULT_ADDR;
 /// assert_eq!(addr, "0.0.0.0:8080");
 /// ```
 #[allow(dead_code)]
 pub const DEFAULT_ADDR: &str = "0.0.0.0:8080";
 /// Run the server with the given address.
 ///
 /// This function starts listening on the specified address and handles incoming
 /// connections in separate threads.
 ///
 /// # Arguments
 /// * `addr` - The address to listen on (e.g., "0.0.0.0:8080")
 ///
 /// # Example
 /// ```
 /// run_server("0.0.0.0:8080");
 /// ```
 pub fn run_server(addr: &str) -> ! {
    log::info!("Starting server on {}", addr);
    let tree = Arc::new(Mutex::new(Tree::new()));
    {
        let mut tree = tree.lock().unwrap();
        tree.add_endpoint("/shell", Box::new(RemoteShell::new("shell")));
        tree.add_endpoint("/tty", Box::new(TTY::new("tty")));
    }
    let listener = TcpTransport::listen(addr).expect("failed to bind");
    log::info!("Listening on {}", addr);
    loop {
        match TcpTransport::accept(&listener) {
            Ok(transport) => {
                log::info!("New connection from {:?}", transport.peer_addr());
                let tree = Arc::clone(&tree);
                std::thread::spawn(move || {
                    handle_connection(transport, tree);
                });
            }
            Err(e) => {
                log::error!("accept error: {:?}", e);
            }
        }
    }
 }
 /// Handle a single connection.
 ///
 /// This function handles the handshake and then processes frames in a loop until
 /// the connection is closed.
 ///
 /// # Arguments
 /// * `transport` - The TCP transport for the connection
 /// * `tree` - Shared access to the tree
 pub fn handle_connection(mut transport: TcpTransport, tree: Arc<Mutex<Tree>>) {
    let (header, _payload) = match transport.recv_frame() {
        Ok(h) => h,
        Err(e) => {
            log::error!("recv error: {:?}", e);
            return;
        }
    };
    if header.frame_type != FrameType::Handshake {
        log::error!("expected handshake");
        return;
    }
    log::info!("Client connected");
    let (ack_header, ack_payload) = make_handshake_ack(true, "/client");
    transport.send_frame(&ack_header, Some(&ack_payload)).expect("send failed");
    loop {
        match transport.recv_frame() {
            Ok((header, payload)) => {
                let response = handle_frame(&header, &payload, &tree);
                if let Some(response) = response {
                    let (resp_header, resp_payload) = match response {
                        Ok((h, p)) => (h, p),
                        Err(e) => {
                            log::error!("handle error: {:?}", e);
                            break;
                        }
                    };
                    transport.send_frame(&resp_header, Some(&resp_payload)).expect("send failed");
                }
                if header.frame_type == FrameType::StreamClose {
                    break;
                }
            }
            Err(e) => {
                log::error!("recv error: {:?}", e);
                break;
            }
        }
    }
    log::info!("Connection closed");
 }
 /// Handle a single frame and return an optional response.
 ///
 /// # Arguments
 /// * `header` - The frame header
 /// * `payload` - The frame payload bytes
 /// * `tree` - Shared access to the tree
 ///
 /// # Returns
 /// * `Some(Ok((header, payload)))` for a response to send
 /// * `Some(Err(e))` for an error
 /// * `None` for no response (async handling)
 ///
 /// # Example
 /// ```
 /// use ush_treetest::protocol::{FrameType, FrameHeader, TcpTransport};
 ///
 /// let header = FrameHeader {
 ///     frame_type: FrameType::Request,
 ///     dst_path: Some("/shell".to_string()),
 ///     src_path: "/client".to_string(),
 ///     request_id: Some(1),
 ///     stream_id: None,
 /// };
 /// let payload = vec![];
 ///
 /// if let Some(result) = handle_frame(&header, &payload, &tree) {
 ///     // Handle response
 /// }
 /// ```
 pub fn handle_frame(
    header: &FrameHeader,
    payload: &[u8],
    tree: &Arc<Mutex<Tree>>,
 ) -> Option<Result<(FrameHeader, Vec<u8>), String>> {
    match header.frame_type {
        FrameType::Request => {
            let request: TreeRequest = match TreeRequest::from_bytes(payload) {
                Ok(r) => r,
                Err(e) => return Some(Err(e.to_string())),
            };
            let dst_path = header.dst_path.as_deref().unwrap_or("/");
            let mut tree = match tree.lock() {
                Ok(t) => t,
                Err(e) => return Some(Err(format!("lock error: {}", e))),
            };
            let response = match request {
                TreeRequest::ListNodes {} => {
                    let names = tree.list_nodes(dst_path).unwrap_or_default();
                    TreeResponse::NodeList { names }
                }
                TreeRequest::ListEndpoints {} => {
                    let endpoints = tree.list_endpoints(dst_path).unwrap_or_default();
                    TreeResponse::EndpointList { endpoints }
                }
                TreeRequest::ListLeaves {} => {
                    let leaves = tree.list_leaves();
                    TreeResponse::LeafList { leaves }
                }
                TreeRequest::GetInfo { path } => {
                    match tree.get_info(&path) {
                        Ok(info) => TreeResponse::NodeInfo { info },
                        Err(e) => return Some(Err(e)),
                    }
                }
                TreeRequest::Exec { ref cmd } => {
                    let (handler, matched_path) = match tree.find_handler(dst_path) {
                        Some(h) => h,
                        None => return Some(Err(format!("path not found: {}", dst_path))),
                    };
                    let result = {
                        let mut handler = match handler.lock() {
                            Ok(h) => h,
                            Err(e) => return Some(Err(format!("lock error: {}", e))),
                        };
                        handler.handle_request(&TreeRequest::Exec { cmd: cmd.clone() }, matched_path)
                    };
                    match result {
                        Ok(resp) => resp,
                        Err(e) => return Some(Err(e)),
                    }
                }
                TreeRequest::StreamOpen { path } => {
                    match tree.open_stream(&path, &header.src_path) {
                        Ok(stream_id) => TreeResponse::StreamOpened { stream_id },
                        Err(e) => return Some(Err(e)),
                    }
                }
                TreeRequest::Resize { .. } => {
                    return Some(Err("unsupported request: Resize".to_string()));
                }
            };
            Some(Ok(make_response(
                &header.src_path,
                header.request_id.unwrap_or(0),
                &response,
            )))
        }
        FrameType::StreamOpen => {
            let dst_path = header.dst_path.as_deref().unwrap_or("/");
            let mut tree = match tree.lock() {
                Ok(t) => t,
                Err(e) => return Some(Err(format!("lock error: {}", e))),
            };
            match tree.open_stream(dst_path, &header.src_path) {
                Ok(stream_id) => {
                    let response = TreeResponse::StreamOpened { stream_id };
                    Some(Ok(make_response(
                        &header.src_path,
                        header.request_id.unwrap_or(0),
                        &response,
                    )))
                }
                Err(e) => Some(Err(e)),
            }
        }
        FrameType::StreamData => {
            let mut tree = match tree.lock() {
                Ok(t) => t,
                Err(e) => return Some(Err(format!("lock error: {}", e))),
            };
            tree.route_stream_data(header, payload).ok();
            None
        }
        FrameType::StreamClose => {
            let mut tree = match tree.lock() {
                Ok(t) => t,
                Err(e) => return Some(Err(format!("lock error: {}", e))),
            };
            if let Some(stream_id) = header.stream_id {
                tree.close_stream(stream_id).ok();
            }
            None
        }
        _ => Some(Err("unsupported frame type".to_string())),
    }
 }
@@ -5,11 +5,12 @@
 use crate::protocol::{TreeRequest, TreeResponse, EndpointType};
 use std::string::String;
 use std::fmt;
 /// Endpoint trait - implemented by all leaf handlers in the tree
 /// 
 /// This trait is object-safe and must be Send + Sync to allow sharing across threads.
-pub trait Endpoint: Send + Sync {
+pub trait Endpoint: Send + Sync + fmt::Debug {
    /// Handle a request and return a response
    fn handle_request(&mut self, request: &TreeRequest, src_path: &str) -> Result<TreeResponse, String>;
@@ -14,16 +14,26 @@ use std::vec::Vec;
 use std::boxed::Box;
 use std::result::Result;
 use std::sync::{Arc, Mutex};
 use std::fmt;
-/// A node in the tree - contains an optional endpoint and child nodes
+/// A node in the tree - contains an optional endpoint and child nodes.
 pub struct Node {
-    endpoint: Option<Arc<Mutex<Box<dyn Endpoint>>>>,
+    endpoint: Option<Arc<Mutex<Box<dyn Endpoint + 'static>>>>,
    children: BTreeMap<String, Node>,
    streams: BTreeMap<u16, Stream>,
    next_stream_id: u16,
    path: String,
 }
 impl fmt::Debug for Node {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("Node")
            .field("path", &self.path)
            .field("children", &self.children.keys().cloned().collect::<Vec<_>>())
            .finish()
    }
 }
 impl Node {
    /// Create a new node with the given path
    pub fn new(path: &str) -> Self {
@@ -108,11 +118,20 @@ impl Node {
    }
 }
-/// Tree structure for routing - contains the root node
+/// Tree structure for routing - contains the root node.
 #[allow(dead_code)]
 pub struct Tree {
    root: Node,
 }
 impl fmt::Debug for Tree {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("Tree")
            .field("root", &self.root.path)
            .finish()
    }
 }
 impl Tree {
    /// Create a new empty tree
    pub fn new() -> Self {