1use poulpy_hal::{
  2    api::{ModuleN, ScratchAvailable, ScratchTakeBasic, SvpPrepare, VecZnxSwitchRing},
  3    layouts::{Backend, DataMut, Module, ScalarZnx, Scratch},
  4    source::Source,
  5};
  6
  7use crate::{
  8    ScratchTakeCore,
  9    encryption::gglwe_ct::GGLWEEncryptSk,
 10    layouts::{
 11        GGLWEInfos, GGLWEToMut, GLWEInfos, GLWESecret, GLWESecretToRef, GLWESwitchingKey, GLWESwitchingKeyDegreesMut, LWEInfos,
 12        prepared::GLWESecretPreparedAlloc,
 13    },
 14};
 15
 16impl GLWESwitchingKey<Vec<u8>> {
 17    pub fn encrypt_sk_tmp_bytes<M, A, BE: Backend>(module: &M, infos: &A) -> usize
 18    where
 19        A: GGLWEInfos,
 20        M: GLWESwitchingKeyEncryptSk<BE>,
 21    {
 22        module.glwe_switching_key_encrypt_sk_tmp_bytes(infos)
 23    }
 24
 25    pub fn encrypt_pk_tmp_bytes<M, A, BE: Backend>(module: &M, infos: &A) -> usize
 26    where
 27        A: GGLWEInfos,
 28        M: GLWESwitchingKeyEncryptPk<BE>,
 29    {
 30        module.glwe_switching_key_encrypt_pk_tmp_bytes(infos)
 31    }
 32}
 33
 34impl<DataSelf: DataMut> GLWESwitchingKey<DataSelf> {
 35    pub fn encrypt_sk<M, S1, S2, BE: Backend>(
 36        &mut self,
 37        module: &M,
 38        sk_in: &S1,
 39        sk_out: &S2,
 40        source_xa: &mut Source,
 41        source_xe: &mut Source,
 42        scratch: &mut Scratch<BE>,
 43    ) where
 44        S1: GLWESecretToRef,
 45        S2: GLWESecretToRef,
 46        M: GLWESwitchingKeyEncryptSk<BE>,
 47        Scratch<BE>: ScratchTakeCore<BE>,
 48    {
 49        module.glwe_switching_key_encrypt_sk(self, sk_in, sk_out, source_xa, source_xe, scratch);
 50    }
 51}
 52
 53pub trait GLWESwitchingKeyEncryptSk<BE: Backend> {
 54    fn glwe_switching_key_encrypt_sk_tmp_bytes<A>(&self, infos: &A) -> usize
 55    where
 56        A: GGLWEInfos;
 57
 58    fn glwe_switching_key_encrypt_sk<R, S1, S2>(
 59        &self,
 60        res: &mut R,
 61        sk_in: &S1,
 62        sk_out: &S2,
 63        source_xa: &mut Source,
 64        source_xe: &mut Source,
 65        scratch: &mut Scratch<BE>,
 66    ) where
 67        R: GGLWEToMut + GLWESwitchingKeyDegreesMut + GGLWEInfos,
 68        S1: GLWESecretToRef,
 69        S2: GLWESecretToRef;
 70}
 71
 72impl<BE: Backend> GLWESwitchingKeyEncryptSk<BE> for Module<BE>
 73where
 74    Self: ModuleN + GGLWEEncryptSk<BE> + GLWESecretPreparedAlloc<BE> + VecZnxSwitchRing + SvpPrepare<BE>,
 75    Scratch<BE>: ScratchTakeCore<BE>,
 76{
 77    fn glwe_switching_key_encrypt_sk_tmp_bytes<A>(&self, infos: &A) -> usize
 78    where
 79        A: GGLWEInfos,
 80    {
 81        self.gglwe_encrypt_sk_tmp_bytes(infos)
 82            .max(ScalarZnx::bytes_of(self.n(), 1))
 83            + ScalarZnx::bytes_of(self.n(), infos.rank_in().into())
 84            + self.bytes_of_glwe_secret_prepared_from_infos(infos)
 85    }
 86
 87    fn glwe_switching_key_encrypt_sk<R, S1, S2>(
 88        &self,
 89        res: &mut R,
 90        sk_in: &S1,
 91        sk_out: &S2,
 92        source_xa: &mut Source,
 93        source_xe: &mut Source,
 94        scratch: &mut Scratch<BE>,
 95    ) where
 96        R: GGLWEToMut + GLWESwitchingKeyDegreesMut + GGLWEInfos,
 97        S1: GLWESecretToRef,
 98        S2: GLWESecretToRef,
 99    {
100        let sk_in: &GLWESecret<&[u8]> = &sk_in.to_ref();
101        let sk_out: &GLWESecret<&[u8]> = &sk_out.to_ref();
102
103        assert!(sk_in.n().0 <= self.n() as u32);
104        assert!(sk_out.n().0 <= self.n() as u32);
105        assert!(
106            scratch.available() >= self.glwe_switching_key_encrypt_sk_tmp_bytes(res),
107            "scratch.available()={} < GLWESwitchingKey::encrypt_sk_tmp_bytes={}",
108            scratch.available(),
109            self.glwe_switching_key_encrypt_sk_tmp_bytes(res)
110        );
111
112        let (mut sk_in_tmp, scratch_1) = scratch.take_scalar_znx(self, sk_in.rank().into());
113        for i in 0..sk_in.rank().into() {
114            self.vec_znx_switch_ring(
115                &mut sk_in_tmp.as_vec_znx_mut(),
116                i,
117                &sk_in.data.as_vec_znx(),
118                i,
119            );
120        }
121
122        let (mut sk_out_tmp, scratch_2) = scratch_1.take_glwe_secret_prepared(self, sk_out.rank());
123        {
124            let (mut tmp, _) = scratch_2.take_scalar_znx(self, 1);
125            for i in 0..sk_out.rank().into() {
126                self.vec_znx_switch_ring(&mut tmp.as_vec_znx_mut(), 0, &sk_out.data.as_vec_znx(), i);
127                self.svp_prepare(&mut sk_out_tmp.data, i, &tmp, 0);
128            }
129        }
130
131        self.gglwe_encrypt_sk(
132            res,
133            &sk_in_tmp,
134            &sk_out_tmp,
135            source_xa,
136            source_xe,
137            scratch_2,
138        );
139
140        *res.input_degree() = sk_in.n();
141        *res.output_degree() = sk_out.n();
142    }
143}
144
145pub trait GLWESwitchingKeyEncryptPk<BE: Backend> {
146    fn glwe_switching_key_encrypt_pk_tmp_bytes<A>(&self, infos: &A) -> usize
147    where
148        A: GGLWEInfos;
149}
150
151impl<BE: Backend> GLWESwitchingKeyEncryptPk<BE> for Module<BE> {
152    fn glwe_switching_key_encrypt_pk_tmp_bytes<A>(&self, _infos: &A) -> usize
153    where
154        A: GGLWEInfos,
155    {
156        unimplemented!()
157    }
158}