use serde::Deserialize;

use std::io;

use std::path::Path;

use anyhow::{Context, Result};

use crate::utils::utils;

#[derive(Clone, Debug, Deserialize, Eq, PartialEq, Default)]

pub struct FallbackSettings {

pub default_toolchain: Option<String>,

}

impl FallbackSettings {

pub(crate) fn new<P: AsRef<Path>>(path: P) -> Result<Option<Self>> {

// Users cannot fix issues with missing/unreadable/invalid centralised files, but logging isn't setup early so

// we can't simply trap all errors and log diagnostics. Ideally we would, and then separate these into different

// sorts of issues, logging messages about errors that should be fixed. Instead we trap some conservative errors

// that hopefully won't lead to too many tickets.

match utils::read_file("fallback settings", path.as_ref()) {

Err(e) => match e.downcast_ref::<io::Error>() {

Some(io_err) => match io_err.kind() {

io::ErrorKind::NotFound | io::ErrorKind::PermissionDenied => Ok(None),

_ => Err(e),

},

None => Err(e),

},

Ok(file_contents) => Ok(Some(

toml::from_str(&file_contents).context("error parsing settings")?,

)),

}

}

}