use std::{

    fs::{File, OpenOptions},

    io::{Read, Write, Result, Error, ErrorKind}

};

pub trait HWServerIO {

    fn write_file(&mut self, name: &str, content: &str) -> Result<()>;

    fn read_file(&mut self, name: &str) -> Result<String>;

}

pub struct EmptyServerIO {}

impl EmptyServerIO {

    pub fn new() -> Self {

        Self {}

    }

}

impl HWServerIO for EmptyServerIO {

    fn write_file(&mut self, _name: &str, _content: &str) -> Result<()> {

        Ok(())

    }

    fn read_file(&mut self, _name: &str) -> Result<String> {

        Ok("".to_string())

    }

}

pub struct FileServerIO {}

impl FileServerIO {

    pub fn new() -> Self {

        Self {}

    }

}

impl HWServerIO for FileServerIO {

    fn write_file(&mut self, name: &str, content: &str) -> Result<()> {

        let mut writer = OpenOptions::new().create(true).write(true).open(name)?;

        writer.write_all(content.as_bytes())

    }

    fn read_file(&mut self, name: &str) -> Result<String> {

        let mut reader = File::open(name)?;

        let mut result = String::new();

        reader.read_to_string(&mut result)?;

        Ok(result)

    }

}