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#![allow(unused)]

use std::cmp::Ordering;
use std::fmt;
use std::fmt::Debug;
use std::hash::Hash;
use std::hash::Hasher;

use anyhow::Result;

use generic_array::ArrayLength;
use generic_array::GenericArray;

use crate::semirings::{
    DivideType, Semiring, SemiringProperties, WeaklyDivisibleSemiring, WeightQuantize,
};

/// Cartesian power semiring: W ^ n.
pub struct PowerWeight<W, N>
where
    W: Semiring,
    N: ArrayLength<W>,
{
    weights: GenericArray<W, N>,
}

impl<W, N> fmt::Display for PowerWeight<W, N>
where
    W: Semiring,
    N: ArrayLength<W>,
{
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        self.weights.as_slice().fmt(f)
    }
}

impl<W, N> fmt::Debug for PowerWeight<W, N>
where
    W: Semiring,
    N: ArrayLength<W>,
{
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        self.weights.as_slice().fmt(f)
    }
}

impl<W, N> Hash for PowerWeight<W, N>
where
    W: Semiring,
    N: ArrayLength<W>,
{
    fn hash<H: Hasher>(&self, state: &mut H) {
        self.weights.as_slice().hash(state);
    }
}

impl<W, N> Clone for PowerWeight<W, N>
where
    W: Semiring,
    N: ArrayLength<W>,
{
    fn clone(&self) -> Self {
        PowerWeight {
            weights: self.weights.clone(),
        }
    }
}

impl<W, N> PartialOrd for PowerWeight<W, N>
where
    W: Semiring,
    N: ArrayLength<W>,
{
    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
        self.weights.partial_cmp(&other.weights)
    }
}

impl<W, N> PartialEq for PowerWeight<W, N>
where
    W: Semiring,
    N: ArrayLength<W>,
{
    fn eq(&self, other: &Self) -> bool {
        self.weights.eq(&other.weights)
    }
}

impl<W, N> AsRef<Self> for PowerWeight<W, N>
where
    W: Semiring,
    N: ArrayLength<W>,
{
    fn as_ref(&self) -> &PowerWeight<W, N> {
        self
    }
}

impl<W, N> Eq for PowerWeight<W, N>
where
    W: Semiring,
    N: ArrayLength<W>,
{
}

//impl<W, N> Semiring for PowerWeight<W, N>
//where
//    W: Semiring,
//    N: ArrayLength<W>,
//{
//    type Type = GenericArray<W, N>;
//    type ReverseSemiring<P> = PowerWeight<W::ReverseSemiring, P>;
//
//    fn zero() -> Self {
//        Self {
//            weights: GenericArray::clone_from_slice(&[W::zero()]),
//        }
//    }
//
//    fn one() -> Self {
//        Self {
//            weights: GenericArray::clone_from_slice(&[W::one()]),
//        }
//    }
//
//    fn new(value: <Self as Semiring>::Type) -> Self {
//        Self { weights: value }
//    }
//
//    fn plus_assign<P: AsRef<Self>>(&mut self, rhs: P) -> Result<()> {
//        for i in 0..self.weights.len() {
//            self.weights[i].plus_assign(&rhs.as_ref().weights[i])?;
//        }
//        Ok(())
//    }
//
//    fn times_assign<P: AsRef<Self>>(&mut self, rhs: P) -> Result<()> {
//        for i in 0..self.weights.len() {
//            self.weights[i].times_assign(&rhs.as_ref().weights[i])?;
//        }
//        Ok(())
//    }
//
//    fn value(&self) -> <Self as Semiring>::Type {
//        self.weights.clone()
//    }
//
//    fn set_value(&mut self, value: <Self as Semiring>::Type) {
//        self.weights = value;
//    }
//
//    fn reverse(&self) -> Self::ReverseSemiring {
//        let mut rw = Vec::with_capacity(self.weights.len());
//        for i in 0..self.weights.len() {
//            rw.push(self.weights[i].reverse());
//        }
//        PowerWeight::new(GenericArray::clone_from(rw))
//    }
//
//    fn properties() -> SemiringProperties {
//        W::properties()
//            & (SemiringProperties::LEFT_SEMIRING
//                | SemiringProperties::RIGHT_SEMIRING
//                | SemiringProperties::COMMUTATIVE
//                | SemiringProperties::IDEMPOTENT)
//    }
//}
//
//impl<W, N> WeaklyDivisibleSemiring for PowerWeight<W, N>
//where
//    W: WeaklyDivisibleSemiring,
//    N: ArrayLength<W>,
//{
//    fn divide(&self, rhs: &Self, divide_type: DivideType) -> Result<Self> {
//        let mut mul = self.clone();
//        for i in 0..self.weights.len() {
//            mul.weights[i] = self.weights[i].divide(&rhs.weights[i], divide_type)?;
//        }
//        Ok(mul)
//    }
//}
//
//impl<W, N> WeightQuantize for PowerWeight<W, N>
//where
//    W: WeightQuantize,
//    N: ArrayLength<W>,
//{
//    fn quantize_assign(&mut self, delta: f32) -> Result<()> {
//        for i in 0..self.weights.len() {
//            unsafe { self.weights.get_unchecked_mut(i).quantize_assign(delta)? };
//        }
//        Ok(())
//    }
//}