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use alloc::vec::Vec;
use miden_core::Felt;
#[cfg(any(test, feature = "testing"))]
use miden_core::Word;
use miden_core::utils::bytes_to_packed_u32_elements;
use miden_protocol::utils::{HexParseError, hex_to_bytes};
// KECCAK256 OUTPUT
// ================================================================================================
/// Keccak256 output representation (32-byte hash)
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub struct Keccak256Output([u8; 32]);
impl Keccak256Output {
/// Creates a new Keccak256 output from a 32-byte array
pub fn new(bytes: [u8; 32]) -> Self {
Self(bytes)
}
/// Creates a [`Keccak256Output`] from a hex string (with or without "0x" prefix).
///
/// The hex string should represent 32 bytes (64 hex characters).
pub fn from_hex(hex_str: &str) -> Result<Self, HexParseError> {
let bytes: [u8; 32] = hex_to_bytes(hex_str)?;
Ok(Self(bytes))
}
/// Returns the inner 32-byte array
pub fn as_bytes(&self) -> &[u8; 32] {
&self.0
}
/// Converts the Keccak256 output to 8 Felt elements (32-byte value as 8 u32 values in
/// little-endian)
pub fn to_elements(&self) -> Vec<Felt> {
bytes_to_packed_u32_elements(&self.0)
}
/// Converts the Keccak256 output to two [`Word`]s: `[lo, hi]`.
///
/// - `lo` contains the first 4 u32-packed felts (bytes 0..16).
/// - `hi` contains the last 4 u32-packed felts (bytes 16..32).
#[cfg(any(test, feature = "testing"))]
pub fn to_words(&self) -> [Word; 2] {
let elements = self.to_elements();
let lo: [Felt; 4] = elements[0..4].try_into().expect("to_elements returns 8 felts");
let hi: [Felt; 4] = elements[4..8].try_into().expect("to_elements returns 8 felts");
[Word::new(lo), Word::new(hi)]
}
}
impl From<[u8; 32]> for Keccak256Output {
fn from(bytes: [u8; 32]) -> Self {
Self::new(bytes)
}
}