//! This file implements the error type for the crate.

use graph::error::Error as GError;

use std::fmt::{Display, Formatter};

#[derive(Debug, Clone, Eq, PartialEq, Ord, PartialOrd)]
pub enum Error {
    UnknownNode(usize),
    UnsupportedOperation,
    Graph(GError),
}

impl Display for Error {
    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
        match self {
            Error::UnknownNode(id) => write!(f, "unknown node: {id}"),
            Error::UnsupportedOperation => write!(f, "unsupported operation"),
            Error::Graph(e) => write!(f, "graph error: {e}"),
        }
    }
}

impl std::error::Error for Error {}

impl From<GError> for Error {
    fn from(e: GError) -> Self {
        Self::Graph(e)
    }
}