use std::{
    env,
    net::TcpStream,
    path::{Path, PathBuf},
    process::Command,
    thread::sleep,
    time::Duration,
};

type DynError = Box<dyn std::error::Error>;

fn main() {
    if let Err(e) = try_main() {
        eprintln!("{e}");
        std::process::exit(-1)
    }
}

fn try_main() -> Result<(), DynError> {
    let task = env::args().nth(1);
    match task.as_deref() {
        Some("local") => local()?,
        _ => print_help(),
    }
    Ok(())
}

fn print_help() {
    eprintln!(
        "Tasks:

local       runs the snake on a local game
"
    )
}

fn local() -> Result<(), DynError> {
    let cargo = env::var("CARGO").unwrap_or_else(|_| "cargo".to_string());

    let mut snake = Command::new(cargo)
        .current_dir(project_root())
        .args(
            ["run", "--bin", "battlesnake"]
                .map(str::to_string)
                .into_iter()
                .chain(env::args().skip(1)),
        )
        .spawn()?;

    while snake.try_wait()?.is_none() {
        // check if port 8000 has been opened. Only then the game can be started
        if TcpStream::connect(("127.0.0.1", 8000)).is_ok() {
            let _game = Command::new("./battlesnake-cli")
                .current_dir(project_root())
                .args([
                    "play",
                    "-W",
                    "11",
                    "-H",
                    "11",
                    "--name",
                    "local test",
                    "--url",
                    "http://localhost:8000",
                    "-g",
                    "solo",
                    "--browser",
                ])
                .status();
            break;
        } else {
            sleep(Duration::from_secs(1));
        }
    }

    snake.kill()?;
    Ok(())
}

fn project_root() -> PathBuf {
    Path::new(&env!("CARGO_MANIFEST_DIR"))
        .ancestors()
        .nth(1)
        .unwrap()
        .to_path_buf()
}