1use poulpy_hal::{
  2    api::{VecZnxCopy, VecZnxFillUniform},
  3    layouts::{Backend, Data, DataMut, DataRef, FillUniform, Module, ReaderFrom, VecZnx, WriterTo, ZnxInfos},
  4    source::Source,
  5};
  6
  7use crate::layouts::{Base2K, Degree, GLWECiphertext, GLWEInfos, LWEInfos, Rank, TorusPrecision, compressed::Decompress};
  8use byteorder::{LittleEndian, ReadBytesExt, WriteBytesExt};
  9use std::fmt;
 10
 11#[derive(PartialEq, Eq, Clone)]
 12pub struct GLWECiphertextCompressed<D: Data> {
 13    pub(crate) data: VecZnx<D>,
 14    pub(crate) base2k: Base2K,
 15    pub(crate) k: TorusPrecision,
 16    pub(crate) rank: Rank,
 17    pub(crate) seed: [u8; 32],
 18}
 19
 20impl<D: Data> LWEInfos for GLWECiphertextCompressed<D> {
 21    fn base2k(&self) -> Base2K {
 22        self.base2k
 23    }
 24
 25    fn k(&self) -> TorusPrecision {
 26        self.k
 27    }
 28
 29    fn size(&self) -> usize {
 30        self.data.size()
 31    }
 32
 33    fn n(&self) -> Degree {
 34        Degree(self.data.n() as u32)
 35    }
 36}
 37impl<D: Data> GLWEInfos for GLWECiphertextCompressed<D> {
 38    fn rank(&self) -> Rank {
 39        self.rank
 40    }
 41}
 42
 43impl<D: DataRef> fmt::Debug for GLWECiphertextCompressed<D> {
 44    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
 45        write!(f, "{self}")
 46    }
 47}
 48
 49impl<D: DataRef> fmt::Display for GLWECiphertextCompressed<D> {
 50    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 51        write!(
 52            f,
 53            "GLWECiphertextCompressed: base2k={} k={} rank={} seed={:?}: {}",
 54            self.base2k(),
 55            self.k(),
 56            self.rank(),
 57            self.seed,
 58            self.data
 59        )
 60    }
 61}
 62
 63impl<D: DataMut> FillUniform for GLWECiphertextCompressed<D> {
 64    fn fill_uniform(&mut self, log_bound: usize, source: &mut Source) {
 65        self.data.fill_uniform(log_bound, source);
 66    }
 67}
 68
 69impl GLWECiphertextCompressed<Vec<u8>> {
 70    pub fn alloc<A>(infos: &A) -> Self
 71    where
 72        A: GLWEInfos,
 73    {
 74        Self::alloc_with(infos.n(), infos.base2k(), infos.k(), infos.rank())
 75    }
 76
 77    pub fn alloc_with(n: Degree, base2k: Base2K, k: TorusPrecision, rank: Rank) -> Self {
 78        Self {
 79            data: VecZnx::alloc(n.into(), 1, k.0.div_ceil(base2k.0) as usize),
 80            base2k,
 81            k,
 82            rank,
 83            seed: [0u8; 32],
 84        }
 85    }
 86
 87    pub fn alloc_bytes<A>(infos: &A) -> usize
 88    where
 89        A: GLWEInfos,
 90    {
 91        Self::alloc_bytes_with(infos.n(), infos.base2k(), infos.k())
 92    }
 93
 94    pub fn alloc_bytes_with(n: Degree, base2k: Base2K, k: TorusPrecision) -> usize {
 95        VecZnx::alloc_bytes(n.into(), 1, k.0.div_ceil(base2k.0) as usize)
 96    }
 97}
 98
 99impl<D: DataMut> ReaderFrom for GLWECiphertextCompressed<D> {
100    fn read_from<R: std::io::Read>(&mut self, reader: &mut R) -> std::io::Result<()> {
101        self.k = TorusPrecision(reader.read_u32::<LittleEndian>()?);
102        self.base2k = Base2K(reader.read_u32::<LittleEndian>()?);
103        self.rank = Rank(reader.read_u32::<LittleEndian>()?);
104        reader.read_exact(&mut self.seed)?;
105        self.data.read_from(reader)
106    }
107}
108
109impl<D: DataRef> WriterTo for GLWECiphertextCompressed<D> {
110    fn write_to<W: std::io::Write>(&self, writer: &mut W) -> std::io::Result<()> {
111        writer.write_u32::<LittleEndian>(self.k.into())?;
112        writer.write_u32::<LittleEndian>(self.base2k.into())?;
113        writer.write_u32::<LittleEndian>(self.rank.into())?;
114        writer.write_all(&self.seed)?;
115        self.data.write_to(writer)
116    }
117}
118
119impl<D: DataMut, B: Backend, DR: DataRef> Decompress<B, GLWECiphertextCompressed<DR>> for GLWECiphertext<D>
120where
121    Module<B>: VecZnxFillUniform + VecZnxCopy,
122{
123    fn decompress(&mut self, module: &Module<B>, other: &GLWECiphertextCompressed<DR>) {
124        #[cfg(debug_assertions)]
125        {
126            assert_eq!(
127                self.n(),
128                other.n(),
129                "invalid receiver: self.n()={} != other.n()={}",
130                self.n(),
131                other.n()
132            );
133            assert_eq!(
134                self.size(),
135                other.size(),
136                "invalid receiver: self.size()={} != other.size()={}",
137                self.size(),
138                other.size()
139            );
140            assert_eq!(
141                self.rank(),
142                other.rank(),
143                "invalid receiver: self.rank()={} != other.rank()={}",
144                self.rank(),
145                other.rank()
146            );
147        }
148
149        let mut source: Source = Source::new(other.seed);
150        self.decompress_internal(module, other, &mut source);
151    }
152}
153
154impl<D: DataMut> GLWECiphertext<D> {
155    pub(crate) fn decompress_internal<DataOther, B: Backend>(
156        &mut self,
157        module: &Module<B>,
158        other: &GLWECiphertextCompressed<DataOther>,
159        source: &mut Source,
160    ) where
161        DataOther: DataRef,
162        Module<B>: VecZnxCopy + VecZnxFillUniform,
163    {
164        #[cfg(debug_assertions)]
165        {
166            assert_eq!(self.rank(), other.rank());
167            debug_assert_eq!(self.size(), other.size());
168        }
169
170        module.vec_znx_copy(&mut self.data, 0, &other.data, 0);
171        (1..(other.rank() + 1).into()).for_each(|i| {
172            module.vec_znx_fill_uniform(other.base2k.into(), &mut self.data, i, source);
173        });
174
175        self.base2k = other.base2k;
176        self.k = other.k;
177    }
178}