use std::{fmt, time};

use humantime::format_duration;

use crate::{progress::Step, unit::DisplayValue};

/// A marker for formatting numbers as duration in renderers, as in `7d4h20m10s`.
#[derive(Copy, Clone, Default, Eq, PartialEq, Ord, PartialOrd, Debug)]
pub struct Duration;

impl DisplayValue for Duration {
    fn display_current_value(&self, w: &mut dyn fmt::Write, value: Step, _upper: Option<Step>) -> fmt::Result {
        w.write_str(&format_duration(time::Duration::new(value as u64, 0)).to_string())
    }
    fn separator(&self, w: &mut dyn fmt::Write, _value: Step, _upper: Option<Step>) -> fmt::Result {
        w.write_str(" of ")
    }
    fn display_upper_bound(&self, w: &mut dyn fmt::Write, upper_bound: Step, _value: Step) -> fmt::Result {
        w.write_str(&format_duration(time::Duration::new(upper_bound as u64, 0)).to_string())
    }

    fn dyn_hash(&self, state: &mut dyn std::hash::Hasher) {
        state.write(&[])
    }

    fn display_unit(&self, _w: &mut dyn fmt::Write, _value: Step) -> fmt::Result {
        Ok(())
    }
}