use crate::{
table::{Compress, Decompress},
DatabaseError,
};
use alloy_primitives::U256;
mod sealed {
pub trait Sealed {}
}
pub trait ScaleValue: sealed::Sealed {}
impl<T> Compress for T
where
T: ScaleValue + parity_scale_codec::Encode + Sync + Send + std::fmt::Debug,
{
type Compressed = Vec<u8>;
fn compress(self) -> Self::Compressed {
parity_scale_codec::Encode::encode(&self)
}
fn compress_to_buf<B: bytes::BufMut + AsMut<[u8]>>(self, buf: &mut B) {
parity_scale_codec::Encode::encode_to(&self, OutputCompat::wrap_mut(buf));
}
}
impl<T> Decompress for T
where
T: ScaleValue + parity_scale_codec::Decode + Sync + Send + std::fmt::Debug,
{
fn decompress(mut value: &[u8]) -> Result<T, DatabaseError> {
parity_scale_codec::Decode::decode(&mut value).map_err(|_| DatabaseError::Decode)
}
}
macro_rules! impl_compression_for_scale {
($($name:tt),+) => {
$(
impl ScaleValue for $name {}
impl sealed::Sealed for $name {}
)+
};
}
impl ScaleValue for Vec<u8> {}
impl sealed::Sealed for Vec<u8> {}
impl_compression_for_scale!(U256);
impl_compression_for_scale!(u8, u32, u16, u64);
#[repr(transparent)]
struct OutputCompat<B>(B);
impl<B> OutputCompat<B> {
fn wrap_mut(buf: &mut B) -> &mut Self {
unsafe { std::mem::transmute(buf) }
}
}
impl<B: bytes::BufMut> parity_scale_codec::Output for OutputCompat<B> {
fn write(&mut self, bytes: &[u8]) {
self.0.put_slice(bytes);
}
fn push_byte(&mut self, byte: u8) {
self.0.put_u8(byte);
}
}