use crate::prelude::*;

use std::fs::{File, OpenOptions};
use std::io::Write;

pub type FileOpenFn = Box<dyn Fn(&str) -> Result<File>>;

pub type FileAppendLineFn = Box<dyn Fn(&str, &str) -> Result<()>>;

pub struct FileEnv {
    pub open: FileOpenFn,
    pub append_line: FileAppendLineFn,
}
impl FileEnv {
    pub fn create(directory: String) -> Self {
        let open_dir = directory.clone();
        let append_dir = directory.clone();
        Self {
            open: Box::new(move |file_name| {
                let path = format!("{}/{}", &open_dir, file_name);
                let file = File::open(&path)?;
                Ok(file)
            }),
            append_line: Box::new(move |file_name, line| {
                let path = format!("{}/{}", &append_dir, file_name);
                let mut file = OpenOptions::new()
                    .write(true)
                    .append(true)
                    .create(true)
                    .open(&path)
                    .unwrap();
                writeln!(file, "{}", line)?;
                Ok(())
            }),
        }
    }
}