//! MCP transport layer — manages child-process and HTTP-based transport
//! for connecting to MCP servers.

use std::process::{Child, Command, Stdio};

/// A running MCP server process connected via stdio.
pub struct McpTransport {
    process: Option<Child>,
}

impl McpTransport {
    pub fn start_child_process(command: &str, args: &[String]) -> anyhow::Result<Self> {
        let child = Command::new(command)
            .args(args)
            .stdin(Stdio::piped())
            .stdout(Stdio::piped())
            .stderr(Stdio::inherit())
            .spawn()?;
        Ok(McpTransport {
            process: Some(child),
        })
    }

    pub fn stop(&mut self) -> anyhow::Result<()> {
        if let Some(mut child) = self.process.take() {
            if let Err(e) = child.kill() {
                tracing::warn!("MCP transport kill error: {e}");
            }
            let _ = child.wait();
        }
        Ok(())
    }
}

impl Drop for McpTransport {
    fn drop(&mut self) {
        if let Some(mut child) = self.process.take() {
            if let Err(e) = child.kill() {
                tracing::warn!("MCP transport kill error: {e}");
            }
            let _ = child.wait();
        }
    }
}