1use poulpy_hal::{
  2    api::{
  3        ScratchAvailable, SvpApplyDftToDft, SvpApplyDftToDftInplace, SvpPPolAllocBytes, SvpPrepare, TakeScalarZnx, TakeVecZnx,
  4        TakeVecZnxBig, TakeVecZnxDft, VecZnxAddInplace, VecZnxAddNormal, VecZnxAddScalarInplace, VecZnxBigAllocBytes,
  5        VecZnxBigNormalize, VecZnxDftAllocBytes, VecZnxDftApply, VecZnxFillUniform, VecZnxIdftApplyConsume, VecZnxIdftApplyTmpA,
  6        VecZnxNormalize, VecZnxNormalizeInplace, VecZnxNormalizeTmpBytes, VecZnxSub, VecZnxSubInplace, VecZnxSwitchRing,
  7    },
  8    layouts::{Backend, DataMut, DataRef, Module, Scratch},
  9    source::Source,
 10};
 11
 12use crate::{
 13    TakeGLWESecret, TakeGLWESecretPrepared,
 14    layouts::{
 15        Degree, GGLWEInfos, GGLWESwitchingKey, GGLWETensorKey, GLWEInfos, GLWESecret, LWEInfos, Rank,
 16        prepared::{GLWESecretPrepared, Prepare},
 17    },
 18};
 19
 20impl GGLWETensorKey<Vec<u8>> {
 21    pub fn encrypt_sk_scratch_space<B: Backend, A>(module: &Module<B>, infos: &A) -> usize
 22    where
 23        A: GGLWEInfos,
 24        Module<B>:
 25            SvpPPolAllocBytes + VecZnxNormalizeTmpBytes + VecZnxDftAllocBytes + VecZnxNormalizeTmpBytes + VecZnxBigAllocBytes,
 26    {
 27        GLWESecretPrepared::alloc_bytes_with(module, infos.rank_out())
 28            + module.vec_znx_dft_alloc_bytes(infos.rank_out().into(), 1)
 29            + module.vec_znx_big_alloc_bytes(1, 1)
 30            + module.vec_znx_dft_alloc_bytes(1, 1)
 31            + GLWESecret::alloc_bytes_with(Degree(module.n() as u32), Rank(1))
 32            + GGLWESwitchingKey::encrypt_sk_scratch_space(module, infos)
 33    }
 34}
 35
 36impl<DataSelf: DataMut> GGLWETensorKey<DataSelf> {
 37    pub fn encrypt_sk<DataSk: DataRef, B: Backend>(
 38        &mut self,
 39        module: &Module<B>,
 40        sk: &GLWESecret<DataSk>,
 41        source_xa: &mut Source,
 42        source_xe: &mut Source,
 43        scratch: &mut Scratch<B>,
 44    ) where
 45        Module<B>: SvpApplyDftToDft<B>
 46            + VecZnxIdftApplyTmpA<B>
 47            + VecZnxAddScalarInplace
 48            + VecZnxDftAllocBytes
 49            + VecZnxBigNormalize<B>
 50            + VecZnxDftApply<B>
 51            + SvpApplyDftToDftInplace<B>
 52            + VecZnxIdftApplyConsume<B>
 53            + VecZnxNormalizeTmpBytes
 54            + VecZnxFillUniform
 55            + VecZnxSubInplace
 56            + VecZnxAddInplace
 57            + VecZnxNormalizeInplace<B>
 58            + VecZnxAddNormal
 59            + VecZnxNormalize<B>
 60            + VecZnxSub
 61            + SvpPrepare<B>
 62            + VecZnxSwitchRing
 63            + SvpPPolAllocBytes,
 64        Scratch<B>:
 65            TakeVecZnxDft<B> + ScratchAvailable + TakeVecZnx + TakeScalarZnx + TakeGLWESecretPrepared<B> + TakeVecZnxBig<B>,
 66    {
 67        #[cfg(debug_assertions)]
 68        {
 69            assert_eq!(self.rank_out(), sk.rank());
 70            assert_eq!(self.n(), sk.n());
 71        }
 72
 73        let n: Degree = sk.n();
 74        let rank: Rank = self.rank_out();
 75
 76        let (mut sk_dft_prep, scratch_1) = scratch.take_glwe_secret_prepared(n, rank);
 77        sk_dft_prep.prepare(module, sk, scratch_1);
 78
 79        let (mut sk_dft, scratch_2) = scratch_1.take_vec_znx_dft(n.into(), rank.into(), 1);
 80
 81        (0..rank.into()).for_each(|i| {
 82            module.vec_znx_dft_apply(1, 0, &mut sk_dft, i, &sk.data.as_vec_znx(), i);
 83        });
 84
 85        let (mut sk_ij_big, scratch_3) = scratch_2.take_vec_znx_big(n.into(), 1, 1);
 86        let (mut sk_ij, scratch_4) = scratch_3.take_glwe_secret(n, Rank(1));
 87        let (mut sk_ij_dft, scratch_5) = scratch_4.take_vec_znx_dft(n.into(), 1, 1);
 88
 89        (0..rank.into()).for_each(|i| {
 90            (i..rank.into()).for_each(|j| {
 91                module.svp_apply_dft_to_dft(&mut sk_ij_dft, 0, &sk_dft_prep.data, j, &sk_dft, i);
 92
 93                module.vec_znx_idft_apply_tmpa(&mut sk_ij_big, 0, &mut sk_ij_dft, 0);
 94                module.vec_znx_big_normalize(
 95                    self.base2k().into(),
 96                    &mut sk_ij.data.as_vec_znx_mut(),
 97                    0,
 98                    self.base2k().into(),
 99                    &sk_ij_big,
100                    0,
101                    scratch_5,
102                );
103
104                self.at_mut(i, j)
105                    .encrypt_sk(module, &sk_ij, sk, source_xa, source_xe, scratch_5);
106            });
107        })
108    }
109}