use async_trait::async_trait;
use bytes::{Bytes, BytesMut};
use std::env;
use std::io;
use std::process;
use tokio_hglib::{PipeClient, UiHandler};

struct BufferedUiHandler {
    buf: BytesMut,
}

#[async_trait]
impl UiHandler for BufferedUiHandler {
    async fn read_data(&mut self, _len: usize) -> io::Result<Bytes> {
        Ok(Bytes::new()) // EOF
    }

    async fn read_line(&mut self, _len: usize) -> io::Result<Bytes> {
        Ok(Bytes::new()) // EOF
    }

    async fn write_output(&mut self, data: Bytes) -> io::Result<()> {
        self.buf.extend(data);
        Ok(())
    }

    async fn write_error(&mut self, data: Bytes) -> io::Result<()> {
        self.buf.extend(data);
        Ok(())
    }
}

#[tokio::main(flavor = "current_thread")]
async fn run() -> io::Result<i32> {
    let mut handler = BufferedUiHandler {
        buf: BytesMut::new(),
    };
    let mut client = PipeClient::spawn_at(".").await?;
    let code = client
        .run_command(&mut handler, env::args().skip(1))
        .await?;
    println!("received:\n{:?}", handler.buf);
    Ok(code)
}

fn main() -> io::Result<()> {
    let code = run()?;
    process::exit(code);
}