use crate::bytes::Bytes32;
use crate::chik_error;
use crate::streamable::Streamable;
use crate::streamable_struct;
use chik_streamable_macro::Streamable;
use sha2::{Digest, Sha256};
use std::convert::TryInto;
#[cfg(feature = "py-bindings")]
use crate::from_json_dict::FromJsonDict;
#[cfg(feature = "py-bindings")]
use crate::to_json_dict::ToJsonDict;
#[cfg(feature = "py-bindings")]
use chik_py_streamable_macro::PyStreamable;
#[cfg(feature = "py-bindings")]
use pyo3::prelude::*;
#[cfg(feature = "py-bindings")]
use pyo3::types::PyBytes;
streamable_struct!(Coin {
parent_coin_info: Bytes32,
puzzle_hash: Bytes32,
amount: u64,
});
impl Coin {
pub fn coin_id(&self) -> [u8; 32] {
let mut hasher = Sha256::new();
hasher.update(self.parent_coin_info);
hasher.update(self.puzzle_hash);
let amount_bytes = self.amount.to_be_bytes();
if self.amount >= 0x8000000000000000_u64 {
hasher.update([0_u8]);
hasher.update(amount_bytes);
} else {
let start = match self.amount {
n if n >= 0x80000000000000_u64 => 0,
n if n >= 0x800000000000_u64 => 1,
n if n >= 0x8000000000_u64 => 2,
n if n >= 0x80000000_u64 => 3,
n if n >= 0x800000_u64 => 4,
n if n >= 0x8000_u64 => 5,
n if n >= 0x80_u64 => 6,
n if n > 0 => 7,
_ => 8,
};
hasher.update(&amount_bytes[start..]);
}
hasher.finalize().as_slice().try_into().unwrap()
}
}
#[cfg(feature = "py-bindings")]
#[cfg_attr(feature = "py-bindings", pymethods)]
impl Coin {
fn name<'p>(&self, py: Python<'p>) -> PyResult<&'p PyBytes> {
Ok(PyBytes::new(py, &self.coin_id()))
}
}
#[cfg(test)]
mod tests {
use super::*;
use rstest::rstest;
#[rstest]
#[case(0, &[])]
#[case(1, &[1])]
#[case(0xff, &[0, 0xff])]
#[case(0xffff, &[0, 0xff, 0xff])]
#[case(0xffffff, &[0, 0xff, 0xff, 0xff])]
#[case(0xffffffff, &[0, 0xff, 0xff, 0xff, 0xff])]
#[case(0xffffffffff, &[0, 0xff, 0xff, 0xff, 0xff, 0xff])]
#[case(0xffffffffffffffff, &[0, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff])]
#[case(0x7f, &[0x7f])]
#[case(0x7fff, &[0x7f, 0xff])]
#[case(0x7fffff, &[0x7f, 0xff, 0xff])]
#[case(0x7fffffff, &[0x7f, 0xff, 0xff, 0xff])]
#[case(0x7fffffffff, &[0x7f, 0xff, 0xff, 0xff, 0xff])]
#[case(0x7fffffffffffffff, &[0x7f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff])]
#[case(0x80, &[0, 0x80])]
#[case(0x8000, &[0, 0x80, 0x00])]
#[case(0x800000, &[0, 0x80, 0x00, 0x00])]
#[case(0x80000000, &[0, 0x80, 0x00, 0x00, 0x00])]
#[case(0x8000000000, &[0, 0x80, 0x00, 0x00, 0x00, 0x00])]
#[case(0x8000000000000000, &[0, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00])]
fn coin_id(#[case] amount: u64, #[case] bytes: &[u8]) {
let parent_coin = b"---foo--- ";
let puzzle_hash = b"---bar--- ";
let c = Coin::new(parent_coin.into(), puzzle_hash.into(), amount);
let mut sha256 = Sha256::new();
sha256.update(parent_coin);
sha256.update(puzzle_hash);
sha256.update(bytes);
assert_eq!(c.coin_id(), &sha256.finalize() as &[u8]);
}
}