use std::fmt::Display;

const ROOT_INO: u64 = 1;

#[derive(Clone, Debug, Eq, PartialEq, Hash, Copy)]
pub struct Ino(u64);

impl Ino {
    pub fn new() -> Self {
        Self(ROOT_INO)
    }

    pub fn next(&mut self) -> &Self {
        self.0 += 1;
        self
    }

    pub fn prev(&mut self) {
        self.0 -= 1;
    }
}

impl From<Ino> for u64 {
    fn from(ino: Ino) -> Self {
        ino.0
    }
}

impl From<u64> for Ino {
    fn from(ino: u64) -> Self {
        Self(ino)
    }
}

impl From<u32> for Ino {
    fn from(ino: u32) -> Self {
        Self(u64::from(ino))
    }
}

impl Display for Ino {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        self.0.fmt(f)
    }
}

impl Default for Ino {
    fn default() -> Self {
        Self::new()
    }
}