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// Copyright © 2026 Mikhail Hogrefe
//
// This file is part of Malachite.
//
// Malachite is free software: you can redistribute it and/or modify it under the terms of the GNU
// Lesser General Public License (LGPL) as published by the Free Software Foundation; either version
// 3 of the License, or (at your option) any later version. See <https://www.gnu.org/licenses/>.
use crate::num::arithmetic::traits::{
ModPowerOf2AbsSquared, ModPowerOf2AbsSquaredAssign, ModPowerOf2Square, ModPowerOf2SquareAssign,
};
macro_rules! impl_mod_power_of_2_abs_squared {
($t:ident) => {
impl ModPowerOf2AbsSquared for $t {
type Output = $t;
/// Computes the squared absolute value of a number modulo $2^k$, which for an unsigned
/// number is its square modulo $2^k$. The input must be already reduced modulo $2^k$.
///
/// $f(x, k) = y$, where $x, y < 2^k$ and $|x|^2 = x^2 \equiv y \mod 2^k$.
///
/// # Worst-case complexity
/// Constant time and additional memory.
///
/// # Panics
/// Panics if `pow` is greater than `Self::WIDTH` or if `self` is greater than or equal
/// to $2^k$.
///
/// # Examples
/// See [here](super::mod_power_of_2_abs_squared#mod_power_of_2_abs_squared).
#[inline]
fn mod_power_of_2_abs_squared(self, pow: u64) -> $t {
self.mod_power_of_2_square(pow)
}
}
impl ModPowerOf2AbsSquaredAssign for $t {
/// Replaces a number with its squared absolute value modulo $2^k$, which for an
/// unsigned number is its square modulo $2^k$. The input must be already reduced modulo
/// $2^k$.
///
/// $x \gets y$, where $x, y < 2^k$ and $|x|^2 = x^2 \equiv y \mod 2^k$.
///
/// # Worst-case complexity
/// Constant time and additional memory.
///
/// # Panics
/// Panics if `pow` is greater than `Self::WIDTH` or if `self` is greater than or equal
/// to $2^k$.
///
/// # Examples
/// See [here](super::mod_power_of_2_abs_squared#mod_power_of_2_abs_squared_assign).
#[inline]
fn mod_power_of_2_abs_squared_assign(&mut self, pow: u64) {
self.mod_power_of_2_square_assign(pow);
}
}
};
}
apply_to_unsigneds!(impl_mod_power_of_2_abs_squared);