use std::fmt;
use std::io;

#[derive(Debug)]
pub enum GitError {
    Io(io::Error),
    InvalidObjectId(String),
    InvalidObject(String),
    ObjectNotFound(String),
    InvalidRef(String),
    RefNotFound(String),
    InvalidIndex(String),
    CorruptPack(String),
}

impl fmt::Display for GitError {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            GitError::Io(e) => write!(f, "IO error: {}", e),
            GitError::InvalidObjectId(s) => write!(f, "invalid object id: {}", s),
            GitError::InvalidObject(s) => write!(f, "invalid object: {}", s),
            GitError::ObjectNotFound(s) => write!(f, "object not found: {}", s),
            GitError::InvalidRef(s) => write!(f, "invalid ref: {}", s),
            GitError::RefNotFound(s) => write!(f, "ref not found: {}", s),
            GitError::InvalidIndex(s) => write!(f, "invalid index: {}", s),
            GitError::CorruptPack(s) => write!(f, "corrupt pack: {}", s),
        }
    }
}

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

impl From<io::Error> for GitError {
    fn from(e: io::Error) -> Self {
        GitError::Io(e)
    }
}