1use std::fmt;
  2
  3use backend::hal::{
  4    api::{FillUniform, Reset, VecZnxFillUniform, ZnxInfos, ZnxView, ZnxViewMut},
  5    layouts::{Backend, Data, DataMut, DataRef, Module, ReaderFrom, VecZnx, WriterTo},
  6};
  7use sampling::source::Source;
  8
  9use crate::{Decompress, Infos, LWECiphertext, SetMetaData};
 10
 11#[derive(PartialEq, Eq, Clone)]
 12pub struct LWECiphertextCompressed<D: Data> {
 13    pub(crate) data: VecZnx<D>,
 14    pub(crate) k: usize,
 15    pub(crate) basek: usize,
 16    pub(crate) seed: [u8; 32],
 17}
 18
 19impl<D: DataRef> fmt::Debug for LWECiphertextCompressed<D> {
 20    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
 21        write!(f, "{}", self)
 22    }
 23}
 24
 25impl<D: DataRef> fmt::Display for LWECiphertextCompressed<D> {
 26    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 27        write!(
 28            f,
 29            "LWECiphertextCompressed: basek={} k={} seed={:?}: {}",
 30            self.basek(),
 31            self.k(),
 32            self.seed,
 33            self.data
 34        )
 35    }
 36}
 37
 38impl<D: DataMut> Reset for LWECiphertextCompressed<D>
 39where
 40    VecZnx<D>: Reset,
 41{
 42    fn reset(&mut self) {
 43        self.data.reset();
 44        self.basek = 0;
 45        self.k = 0;
 46        self.seed = [0u8; 32];
 47    }
 48}
 49
 50impl<D: DataMut> FillUniform for LWECiphertextCompressed<D>
 51where
 52    VecZnx<D>: FillUniform,
 53{
 54    fn fill_uniform(&mut self, source: &mut Source) {
 55        self.data.fill_uniform(source);
 56    }
 57}
 58
 59impl LWECiphertextCompressed<Vec<u8>> {
 60    pub fn alloc(basek: usize, k: usize) -> Self {
 61        Self {
 62            data: VecZnx::alloc(1, 1, k.div_ceil(basek)),
 63            k: k,
 64            basek: basek,
 65            seed: [0u8; 32],
 66        }
 67    }
 68}
 69
 70impl<D: Data> Infos for LWECiphertextCompressed<D>
 71where
 72    VecZnx<D>: ZnxInfos,
 73{
 74    type Inner = VecZnx<D>;
 75
 76    fn n(&self) -> usize {
 77        &self.inner().n() - 1
 78    }
 79
 80    fn inner(&self) -> &Self::Inner {
 81        &self.data
 82    }
 83
 84    fn basek(&self) -> usize {
 85        self.basek
 86    }
 87
 88    fn k(&self) -> usize {
 89        self.k
 90    }
 91}
 92
 93impl<DataSelf: DataMut> SetMetaData for LWECiphertextCompressed<DataSelf> {
 94    fn set_k(&mut self, k: usize) {
 95        self.k = k
 96    }
 97
 98    fn set_basek(&mut self, basek: usize) {
 99        self.basek = basek
100    }
101}
102
103use byteorder::{LittleEndian, ReadBytesExt, WriteBytesExt};
104
105impl<D: DataMut> ReaderFrom for LWECiphertextCompressed<D> {
106    fn read_from<R: std::io::Read>(&mut self, reader: &mut R) -> std::io::Result<()> {
107        self.k = reader.read_u64::<LittleEndian>()? as usize;
108        self.basek = reader.read_u64::<LittleEndian>()? as usize;
109        reader.read(&mut self.seed)?;
110        self.data.read_from(reader)
111    }
112}
113
114impl<D: DataRef> WriterTo for LWECiphertextCompressed<D> {
115    fn write_to<W: std::io::Write>(&self, writer: &mut W) -> std::io::Result<()> {
116        writer.write_u64::<LittleEndian>(self.k as u64)?;
117        writer.write_u64::<LittleEndian>(self.basek as u64)?;
118        writer.write_all(&self.seed)?;
119        self.data.write_to(writer)
120    }
121}
122
123impl<D: DataMut, B: Backend, DR: DataRef> Decompress<B, LWECiphertextCompressed<DR>> for LWECiphertext<D> {
124    fn decompress(&mut self, module: &Module<B>, other: &LWECiphertextCompressed<DR>)
125    where
126        Module<B>: VecZnxFillUniform,
127    {
128        let mut source = Source::new(other.seed);
129        module.vec_znx_fill_uniform(other.basek(), &mut self.data, 0, other.k(), &mut source);
130        (0..self.size()).for_each(|i| {
131            self.data.at_mut(0, i)[0] = other.data.at(0, i)[0];
132        });
133    }
134}