use std::fmt;

use std::time::Duration;

use http::HeaderValue;

use crate::util::IterExt;

use crate::Error;

#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]

pub(crate) struct Seconds(Duration);

impl Seconds {

    pub(crate) fn from_val(val: &HeaderValue) -> Option<Self> {

        let secs = val.to_str().ok()?.parse().ok()?;

        Some(Self::from_secs(secs))

    }

    pub(crate) fn from_secs(secs: u64) -> Self {

        Self::from(Duration::from_secs(secs))

    }

    pub(crate) fn as_u64(&self) -> u64 {

        self.0.as_secs()

    }

}

impl super::TryFromValues for Seconds {

    fn try_from_values<'i, I>(values: &mut I) -> Result<Self, Error>

    where

        I: Iterator<Item = &'i HeaderValue>,

    {

        values

            .just_one()

            .and_then(Seconds::from_val)

            .ok_or_else(Error::invalid)

    }

}

impl<'a> From<&'a Seconds> for HeaderValue {

    fn from(secs: &'a Seconds) -> HeaderValue {

        secs.0.as_secs().into()

    }

}

impl From<Duration> for Seconds {

    fn from(dur: Duration) -> Seconds {

        debug_assert!(dur.subsec_nanos() == 0);

        Seconds(dur)

    }

}

impl From<Seconds> for Duration {

    fn from(secs: Seconds) -> Duration {

        secs.0

    }

}

impl fmt::Debug for Seconds {

    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {

        write!(f, "{}s", self.0.as_secs())

    }

}

impl fmt::Display for Seconds {

    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {

        fmt::Display::fmt(&self.0.as_secs(), f)

    }

}