use std::{fs, path::PathBuf, process, env};

fn find_target_dir(path: PathBuf) -> Result<bool, std::io::Error> {
    for entry in fs::read_dir(path)? {
        let entry = entry?;
        let p = entry.path();
        if p.is_dir() && p.ends_with("target") {
            return Ok(true);
        }
    }
    Ok(false)
}

fn execute_clean(path: PathBuf) -> Result<(), std::io::Error> {
    let _cmd = process::Command::new("cargo")
        .current_dir(path)
        .arg("clean")
        .status()?;
    Ok(())
}

fn clean_in_dir(path: PathBuf) -> Result<u64, std::io::Error> {
    let mut cleaned: u64 = 0;
    for entry in fs::read_dir(path)? {
        let entry = entry?;
        let p = entry.path();
        if p.is_dir() {
            let needed = find_target_dir(p.clone())?;
            if needed {
                println!(" => {}", p.display());
                execute_clean(p)?;
                cleaned += 1;
            }
        }
    }
    Ok(cleaned)
}

fn main() -> Result<(), std::io::Error> {
    println!("Rust Pan");
    let cwd = env::current_dir()?;
    let cleand = clean_in_dir(cwd)?;
    println!("Cleaned {} crates", cleand);
    Ok(())
}