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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::{
ModAbsSquared, ModAbsSquaredAssign, ModSquare, ModSquareAssign,
};
macro_rules! impl_mod_abs_squared {
($t:ident) => {
impl ModAbsSquared for $t {
type Output = $t;
/// Computes the squared absolute value of a number modulo another number $m$, which for
/// an unsigned number is its square modulo $m$. The input must be already reduced
/// modulo $m$.
///
/// $f(x, m) = y$, where $x, y < m$ and $|x|^2 = x^2 \equiv y \mod m$.
///
/// # Worst-case complexity
/// Constant time and additional memory.
///
/// # Panics
/// Panics if `self` is greater than or equal to `m`.
///
/// # Examples
/// See [here](super::mod_abs_squared#mod_abs_squared).
#[inline]
fn mod_abs_squared(self, m: $t) -> $t {
self.mod_square(m)
}
}
impl ModAbsSquaredAssign for $t {
/// Replaces a number with its squared absolute value modulo another number $m$, which
/// for an unsigned number is its square modulo $m$. The input must be already reduced
/// modulo $m$.
///
/// $x \gets y$, where $x, y < m$ and $|x|^2 = x^2 \equiv y \mod m$.
///
/// # Worst-case complexity
/// Constant time and additional memory.
///
/// # Panics
/// Panics if `self` is greater than or equal to `m`.
///
/// # Examples
/// See [here](super::mod_abs_squared#mod_abs_squared_assign).
#[inline]
fn mod_abs_squared_assign(&mut self, m: $t) {
self.mod_square_assign(m);
}
}
};
}
apply_to_unsigneds!(impl_mod_abs_squared);