use std::hash::{Hash, Hasher};

use serde::{Deserialize, Deserializer, Serialize};

#[derive(Clone, Copy, Debug, Serialize)]
#[serde(transparent)]
pub struct OrderedFloat(f64);

impl OrderedFloat {
	#[inline]
	pub fn new(t: f64) -> Self {
		debug_assert!(!t.is_nan());
		Self(t)
	}

	#[inline]
	pub const fn get(&self) -> f64 { self.0 }
}

impl Hash for OrderedFloat {
	fn hash<H: Hasher>(&self, state: &mut H) { self.0.to_bits().hash(state) }
}

impl PartialEq for OrderedFloat {
	fn eq(&self, other: &Self) -> bool { self.0.to_bits() == other.0.to_bits() }
}

impl Eq for OrderedFloat {}

impl<'de> Deserialize<'de> for OrderedFloat {
	fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
	where
		D: Deserializer<'de>,
	{
		let f = f64::deserialize(deserializer)?;
		if f.is_nan() {
			Err(serde::de::Error::custom("NaN is not a valid OrderedFloat"))
		} else {
			Ok(Self::new(f))
		}
	}
}