use std::path::PathBuf;

#[derive(Debug)]
pub enum SandboxError {
    HomeNotSet,
    BwrapNotFound,
    CommandNotFound(PathBuf),
    CommandNotExecutable(PathBuf),
    RwPathMissing(PathBuf),
    RoPathMissing(PathBuf),
    ChdirMissing(PathBuf),
    CurrentDirUnavailable(std::io::Error),
    GlobPattern(glob::PatternError),
    Io(std::io::Error),
}

impl std::fmt::Display for SandboxError {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        match self {
            Self::HomeNotSet => write!(
                f,
                "$HOME is not set; cannot determine which paths to protect"
            ),
            Self::BwrapNotFound => write!(
                f,
                "bwrap not found; install bubblewrap (e.g. `apt install bubblewrap` or `pacman -S bubblewrap`)"
            ),
            Self::CommandNotFound(p) => write!(f, "command not found: {}", p.display()),
            Self::CommandNotExecutable(p) => {
                write!(f, "command is not executable: {}", p.display())
            }
            Self::RwPathMissing(p) => write!(f, "--rw path does not exist: {}", p.display()),
            Self::RoPathMissing(p) => write!(f, "--ro path does not exist: {}", p.display()),
            Self::ChdirMissing(p) => write!(f, "--chdir path does not exist: {}", p.display()),
            Self::CurrentDirUnavailable(e) => write!(f, "cannot determine current directory: {e}"),
            Self::GlobPattern(e) => write!(f, "invalid glob pattern: {e}"),
            Self::Io(e) => write!(f, "I/O error: {e}"),
        }
    }
}

impl std::error::Error for SandboxError {
    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
        match self {
            Self::CurrentDirUnavailable(e) => Some(e),
            Self::GlobPattern(e) => Some(e),
            Self::Io(e) => Some(e),
            _ => None,
        }
    }
}

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

impl From<glob::PatternError> for SandboxError {
    fn from(e: glob::PatternError) -> Self {
        Self::GlobPattern(e)
    }
}