use std::collections::HashMap;
use std::fs;
use std::fs::{File, OpenOptions};
use std::io;
use std::io::Result;
use std::path::PathBuf;

pub struct Logger {
    log_dir: PathBuf,
    fds: HashMap<String, File>,
}

impl Logger {
    fn get_file(&mut self, target: &str) -> Result<&mut File> {
        if let Some(fd) = self.fds.get_mut(target) {
            return Ok(fd);
        }

        let mut file_path = self.log_dir.clone();
        file_path.push(&format!("{}.txt", target));
        let fd = OpenOptions::new().append(true).open(file_path)?;
        self.fds.insert(target.to_owned(), fd);
        self.get_file(target)
    }
}