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use crate::util::*;
use bls12_381_plus::Scalar;
use ff::Field;
use rand_core::RngCore;
use serde::{Deserialize, Serialize};
use subtle::CtOption;
#[derive(Debug, Copy, Clone, Eq, PartialEq, Deserialize, Serialize)]
pub struct Message(pub Scalar);
impl Message {
pub const BYTES: usize = 32;
pub fn hash<B: AsRef<[u8]>>(data: B) -> Self {
Self(hash_to_scalar(data))
}
pub fn random(rng: impl RngCore) -> Self {
Self(Scalar::random(rng))
}
pub fn to_bytes(&self) -> [u8; Self::BYTES] {
scalar_to_bytes(self.0)
}
pub fn from_bytes(bytes: &[u8; Self::BYTES]) -> CtOption<Self> {
scalar_from_bytes(bytes).map(Self)
}
}
#[cfg(test)]
mod test {
use crate::lib::Message;
use rand::thread_rng;
#[test]
fn test_message() {
let h = [0_u8; 32];
let m = Message::hash(h);
let mr = Message::random(thread_rng());
assert_ne!(m, mr);
let mb = m.to_bytes();
let m2 = Message::from_bytes(&mb).unwrap();
assert_eq!(m, m2);
}
}