zellij/src/client/mod.rs

pub mod boundaries;
pub mod layout;
pub mod pane_resizer;
pub mod panes;
pub mod tab;

use std::env::current_exe;
use std::io::{self, Write};
use std::path::Path;
use std::process::Command;
use std::sync::mpsc;
use std::thread;

use crate::cli::CliArgs;
use crate::common::{
    command_is_executing::CommandIsExecuting,
    errors::ContextType,
    input::config::Config,
    input::handler::input_loop,
    input::options::Options,
    ipc::{ClientToServerMsg, ServerToClientMsg},
    os_input_output::ClientOsApi,
    thread_bus::{SenderType, SenderWithContext, SyncChannelWithContext},
    utils::consts::ZELLIJ_IPC_PIPE,
};

/// Instructions related to the client-side application and sent from server to client
#[derive(Debug, Clone)]
pub enum ClientInstruction {
    Error(String),
    Render(Option<String>),
    UnblockInputThread,
    Exit,
    ServerError(String),
}

impl From<ServerToClientMsg> for ClientInstruction {
    fn from(instruction: ServerToClientMsg) -> Self {
        match instruction {
            ServerToClientMsg::Exit => ClientInstruction::Exit,
            ServerToClientMsg::Render(buffer) => ClientInstruction::Render(buffer),
            ServerToClientMsg::UnblockInputThread => ClientInstruction::UnblockInputThread,
            ServerToClientMsg::ServerError(backtrace) => ClientInstruction::ServerError(backtrace),
        }
    }
}

fn spawn_server(socket_path: &Path) -> io::Result<()> {
    let status = Command::new(current_exe()?)
        .arg("--server")
        .arg(socket_path)
        .status()?;
    if status.success() {
        Ok(())
    } else {
        let msg = "Process returned non-zero exit code";
        let err_msg = match status.code() {
            Some(c) => format!("{}: {}", msg, c),
            None => msg.to_string(),
        };
        Err(io::Error::new(io::ErrorKind::Other, err_msg))
    }
}

pub fn start_client(mut os_input: Box<dyn ClientOsApi>, opts: CliArgs, config: Config) {
    let clear_client_terminal_attributes = "\u{1b}[?1l\u{1b}=\u{1b}[r\u{1b}12l\u{1b}[?1000l\u{1b}[?1002l\u{1b}[?1003l\u{1b}[?1005l\u{1b}[?1006l\u{1b}[?12l";
    let take_snapshot = "\u{1b}[?1049h";
    let bracketed_paste = "\u{1b}[?2004h";
    os_input.unset_raw_mode(0);
    let _ = os_input
        .get_stdout_writer()
        .write(take_snapshot.as_bytes())
        .unwrap();
    let _ = os_input
        .get_stdout_writer()
        .write(clear_client_terminal_attributes.as_bytes())
        .unwrap();
    std::env::set_var(&"ZELLIJ", "0");

    #[cfg(not(test))]
    spawn_server(&*ZELLIJ_IPC_PIPE).unwrap();

    let mut command_is_executing = CommandIsExecuting::new();

    let config_options = Options::from_cli(&config.options, opts.option.clone());

    let full_screen_ws = os_input.get_terminal_size_using_fd(0);
    os_input.connect_to_server(&*ZELLIJ_IPC_PIPE);
    os_input.send_to_server(ClientToServerMsg::NewClient(
        full_screen_ws,
        opts,
        config_options,
    ));
    os_input.set_raw_mode(0);
    let _ = os_input
        .get_stdout_writer()
        .write(bracketed_paste.as_bytes())
        .unwrap();

    let (send_client_instructions, receive_client_instructions): SyncChannelWithContext<
        ClientInstruction,
    > = mpsc::sync_channel(50);
    let send_client_instructions =
        SenderWithContext::new(SenderType::SyncSender(send_client_instructions));

    #[cfg(not(test))]
    std::panic::set_hook({
        use crate::errors::handle_panic;
        let send_client_instructions = send_client_instructions.clone();
        Box::new(move |info| {
            handle_panic(info, &send_client_instructions);
        })
    });

    let _stdin_thread = thread::Builder::new()
        .name("stdin_handler".to_string())
        .spawn({
            let send_client_instructions = send_client_instructions.clone();
            let command_is_executing = command_is_executing.clone();
            let os_input = os_input.clone();
            move || {
                input_loop(
                    os_input,
                    config,
                    command_is_executing,
                    send_client_instructions,
                )
            }
        });

    let _signal_thread = thread::Builder::new()
        .name("signal_listener".to_string())
        .spawn({
            let os_input = os_input.clone();
            move || {
                os_input.receive_sigwinch(Box::new({
                    let os_api = os_input.clone();
                    move || {
                        os_api.send_to_server(ClientToServerMsg::TerminalResize(
                            os_api.get_terminal_size_using_fd(0),
                        ));
                    }
                }));
            }
        })
        .unwrap();

    let router_thread = thread::Builder::new()
        .name("router".to_string())
        .spawn({
            let os_input = os_input.clone();
            let mut should_break = false;
            move || loop {
                let (instruction, err_ctx) = os_input.recv_from_server();
                err_ctx.update_thread_ctx();
                match instruction {
                    ServerToClientMsg::Exit | ServerToClientMsg::ServerError(_) => {
                        should_break = true;
                    }
                    _ => {}
                }
                send_client_instructions.send(instruction.into()).unwrap();
                if should_break {
                    break;
                }
            }
        })
        .unwrap();

    let handle_error = |backtrace: String| {
        os_input.unset_raw_mode(0);
        let goto_start_of_last_line = format!("\u{1b}[{};{}H", full_screen_ws.rows, 1);
        let restore_snapshot = "\u{1b}[?1049l";
        let error = format!(
            "{}\n{}{}",
            goto_start_of_last_line, restore_snapshot, backtrace
        );
        let _ = os_input
            .get_stdout_writer()
            .write(error.as_bytes())
            .unwrap();
        std::process::exit(1);
    };

    loop {
        let (client_instruction, mut err_ctx) = receive_client_instructions
            .recv()
            .expect("failed to receive app instruction on channel");

        err_ctx.add_call(ContextType::Client((&client_instruction).into()));
        match client_instruction {
            ClientInstruction::Exit => break,
            ClientInstruction::Error(backtrace) => {
                let _ = os_input.send_to_server(ClientToServerMsg::ClientExit);
                handle_error(backtrace);
            }
            ClientInstruction::ServerError(backtrace) => {
                handle_error(backtrace);
            }
            ClientInstruction::Render(output) => {
                if output.is_none() {
                    break;
                }
                let mut stdout = os_input.get_stdout_writer();
                stdout
                    .write_all(&output.unwrap().as_bytes())
                    .expect("cannot write to stdout");
                stdout.flush().expect("could not flush");
            }
            ClientInstruction::UnblockInputThread => {
                command_is_executing.unblock_input_thread();
            }
        }
    }

    let _ = os_input.send_to_server(ClientToServerMsg::ClientExit);
    router_thread.join().unwrap();

    // cleanup();
    let reset_style = "\u{1b}[m";
    let show_cursor = "\u{1b}[?25h";
    let restore_snapshot = "\u{1b}[?1049l";
    let goto_start_of_last_line = format!("\u{1b}[{};{}H", full_screen_ws.rows, 1);
    let goodbye_message = format!(
        "{}\n{}{}{}Bye from Zellij!\n",
        goto_start_of_last_line, restore_snapshot, reset_style, show_cursor
    );

    os_input.unset_raw_mode(0);
    let mut stdout = os_input.get_stdout_writer();
    let _ = stdout.write(goodbye_message.as_bytes()).unwrap();
    stdout.flush().unwrap();
}