use std::error::Error;
use std::fmt::{Display, Formatter};
use std::io;

#[derive(Debug)]
pub enum LoadErr {
    CantReadFile,
    Invalid,
    BufferTooShort,
    IO(io::Error),
}

impl From<io::Error> for LoadErr {
    fn from(err: io::Error) -> Self {
        if err.kind() == io::ErrorKind::UnexpectedEof {
            Self::BufferTooShort
        } else {
            Self::IO(err)
        }
    }
}

impl Display for LoadErr {
    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
        write!(f, "{self:?}")
    }
}

impl Error for LoadErr {}

// This should be a different enum per part of file. Either return a list of these or take a callback
// TODO: https://users.rust-lang.org/t/validation-monad/117894/6
//
// load was partially successful. These are the defects that are in the now loaded project
// #[derive(Debug, Clone, Copy)]
// #[non_exhaustive]
// pub enum LoadDefect {
//     /// deletes the effect
//     UnknownEffect,
//     /// replaced with empty text
//     InvalidText,
//     /// tries to replace with a sane default value
//     OutOfBoundsValue,
//     /// skips loading of the pointed to value
//     OutOfBoundsPtr,
// }