live-cli/src/command.rs

use crate::event::EventMessage;
use crate::CommandOptions;
use anyhow::bail;
use anyhow::Context;
use anyhow::Result;
use crossbeam::channel::Receiver;
use crossbeam::channel::Sender;
use parking_lot::RwLock;
use ropey::Rope;
use std::sync::Arc;
use std::{
    io::Write,
    process::{Command, Stdio},
};

pub type CommandRequest = (Arc<RwLock<CommandOptions>>, Arc<String>);

#[derive(Debug)]
pub enum CommandCompleted {
    Success(CommandResult),
    Failure(Rope),
}

#[derive(Debug)]
pub struct CommandResult {
    pub status_success: bool,
    pub stdout: Rope,
    pub stderr: Rope,
}

pub fn command_event_loop(
    command_request_receiver: Receiver<CommandRequest>,
    event_sender: Sender<EventMessage>,
) -> Result<()> {
    loop {
        match command_request_receiver.recv() {
        // TODO: Drain the command request channel so we only run the command once with the latest value
        // Could use https://docs.rs/single_value_channel/latest/single_value_channel/
            Ok(command_request) => {
                event_sender.send(EventMessage::CommandCompleted(
                    match run_inner(&command_request) {
                        Ok(c) => {
                            // If there was no stdout and the command failed, don't touch stdout
                            if !c.status_success && c.stdout.len_bytes() == 0 {
                                CommandCompleted::Failure(c.stderr)
                            } else {
                                CommandCompleted::Success(c)
                            }
                        }
                        Err(e) => CommandCompleted::Failure(Rope::from_str(&e.to_string())),
                    },
                ))?;
            }
            Err(e) => {
                event_sender.send(EventMessage::CommandLoopStopped)?;
                bail!("Crossterm read error: {}", e);
            }
        }
    }
}

fn run_inner(command_request: &CommandRequest) -> Result<CommandResult> {
    // Spawn the child
    let mut child = {
        let request = command_request.0.read();

        let mut command = Command::new(&request.command);
        command
            .stdin(Stdio::piped())
            .stdout(Stdio::piped())
            .stderr(Stdio::piped())
            .args(&request.hidden_options);

        if request.wordsplit {
            match shellwords::split(&request.cmdline) {
                Ok(a) => {
                    command.args(a);
                }
                Err(e) => {
                    bail!("Argument error: {e:?}");
                }
            }
        } else {
            // TODO: Avoid cloning here
            command.arg(&request.cmdline);
        }

        std::mem::drop(request);

        command.spawn()
    }?;

    let mut stdin = child.stdin.take().context("Could not take stdin")?;
    let text_orig_clone = command_request.1.clone();
    std::thread::spawn(move || {
        let _result = stdin.write_all(text_orig_clone.as_bytes());
    });

    // Collect the output
    let output = child.wait_with_output()?;

    Ok(CommandResult {
        status_success: output.status.success(),
        stdout: Rope::from_reader(&output.stdout[..])?,
        stderr: Rope::from_reader(&output.stderr[..])?,
    })
}