use std::{fs::File, io::{BufReader, ErrorKind, Read}, path::Path};
use thiserror::Error;

#[derive(Debug, Error)]
pub enum ReadError {
    #[error("file not found")]
    FileNotFound,

    #[error("invalid file format")]
    InvalidFormat,

    #[error("unhandled read error")]
    Unhandled(ErrorKind),
}

pub fn read_file(path: &Path) -> Result<Vec<u8>, ReadError> {
    let file = File::open(path).map_err(|err| {
        match err.kind() {
            ErrorKind::NotFound => ReadError::FileNotFound,
            _ => ReadError::Unhandled( err.kind()),
        }
    })?;
    read_fh(&file)
}

pub fn read_fh(file: &File) -> Result<Vec<u8>, ReadError> {
    let mut content = Vec::new();
    let mut reader = BufReader::new(file);
    reader.read_to_end(&mut content).map_err(|err| ReadError::Unhandled(err.kind()))?;
    Ok(content)
}