use std::num::NonZeroU64;

#[allow(unused_imports)]
use crate::prelude::*;


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

/// Constructors.
impl Line {
    pub const fn from_index(index: u64) -> Self {
        Self(index)
    }

    pub const fn from_linenr(linenr: NonZeroU64) -> Self {
        Self(linenr.get() - 1)
    }

    pub const fn next(self) -> Self {
        Self::from_index(self.index() + 1)
    }

    /// Panics if self is line index 0.
    pub const fn prev(self) -> Self {
        Self::from_index(self.index() - 1)
    }
}

/// Getters.
impl Line {
    /// 0-indexed
    pub const fn index(self) -> u64 {
        self.0
    }

    /// 1-indexed
    pub const fn linenr(self) -> u64 {
        self.0 + 1
    }
}

pub struct Lines(Vec<Line>);