1use std::collections::HashMap;
  2
  3use backend::{FFT64, FillUniform, Module, ScratchOwned, Stats, VecZnxOps, ZnxView, ZnxViewMut};
  4use sampling::source::Source;
  5
  6use crate::{
  7    automorphism::AutomorphismKey,
  8    elem::Infos,
  9    glwe_ciphertext::GLWECiphertext,
 10    glwe_plaintext::GLWEPlaintext,
 11    keys::{SecretKey, SecretKeyFourier},
 12    test_fft64::gglwe::var_noise_gglwe_product,
 13};
 14
 15#[test]
 16fn trace_inplace() {
 17    (1..4).for_each(|rank| {
 18        println!("test trace_inplace rank: {}", rank);
 19        test_trace_inplace(11, 8, 54, 3.2, rank);
 20    });
 21}
 22
 23fn test_trace_inplace(log_n: usize, basek: usize, k: usize, sigma: f64, rank: usize) {
 24    let module: Module<FFT64> = Module::<FFT64>::new(1 << log_n);
 25
 26    let k_autokey: usize = k + basek;
 27
 28    let rows: usize = (k + basek - 1) / basek;
 29
 30    let mut ct: GLWECiphertext<Vec<u8>> = GLWECiphertext::alloc(&module, basek, k, rank);
 31    let mut pt_want: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::alloc(&module, basek, k);
 32    let mut pt_have: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::alloc(&module, basek, k);
 33
 34    let mut source_xs: Source = Source::new([0u8; 32]);
 35    let mut source_xe: Source = Source::new([0u8; 32]);
 36    let mut source_xa: Source = Source::new([0u8; 32]);
 37
 38    let mut scratch: ScratchOwned = ScratchOwned::new(
 39        GLWECiphertext::encrypt_sk_scratch_space(&module, ct.size())
 40            | GLWECiphertext::decrypt_scratch_space(&module, ct.size())
 41            | AutomorphismKey::generate_from_sk_scratch_space(&module, rank, k_autokey)
 42            | GLWECiphertext::trace_inplace_scratch_space(&module, ct.size(), k_autokey, rank),
 43    );
 44
 45    let mut sk: SecretKey<Vec<u8>> = SecretKey::alloc(&module, rank);
 46    sk.fill_ternary_prob(0.5, &mut source_xs);
 47
 48    let mut sk_dft: SecretKeyFourier<Vec<u8>, FFT64> = SecretKeyFourier::alloc(&module, rank);
 49    sk_dft.dft(&module, &sk);
 50
 51    let mut data_want: Vec<i64> = vec![0i64; module.n()];
 52
 53    data_want
 54        .iter_mut()
 55        .for_each(|x| *x = source_xa.next_i64() & 0xFF);
 56
 57    pt_have
 58        .data
 59        .fill_uniform(basek, 0, pt_have.size(), &mut source_xa);
 60
 61    ct.encrypt_sk(
 62        &module,
 63        &pt_have,
 64        &sk_dft,
 65        &mut source_xa,
 66        &mut source_xe,
 67        sigma,
 68        scratch.borrow(),
 69    );
 70
 71    let mut auto_keys: HashMap<i64, AutomorphismKey<Vec<u8>, FFT64>> = HashMap::new();
 72    let gal_els: Vec<i64> = GLWECiphertext::trace_galois_elements(&module);
 73    gal_els.iter().for_each(|gal_el| {
 74        let mut key: AutomorphismKey<Vec<u8>, FFT64> = AutomorphismKey::alloc(&module, basek, k_autokey, rows, rank);
 75        key.generate_from_sk(
 76            &module,
 77            *gal_el,
 78            &sk,
 79            &mut source_xa,
 80            &mut source_xe,
 81            sigma,
 82            scratch.borrow(),
 83        );
 84        auto_keys.insert(*gal_el, key);
 85    });
 86
 87    ct.trace_inplace(&module, 0, 5, &auto_keys, scratch.borrow());
 88    ct.trace_inplace(&module, 5, log_n, &auto_keys, scratch.borrow());
 89
 90    (0..pt_want.size()).for_each(|i| pt_want.data.at_mut(0, i)[0] = pt_have.data.at(0, i)[0]);
 91
 92    ct.decrypt(&module, &mut pt_have, &sk_dft, scratch.borrow());
 93
 94    module.vec_znx_sub_ab_inplace(&mut pt_want.data, 0, &pt_have.data, 0);
 95    module.vec_znx_normalize_inplace(basek, &mut pt_want.data, 0, scratch.borrow());
 96
 97    let noise_have = pt_want.data.std(0, basek).log2();
 98
 99    let mut noise_want: f64 = var_noise_gglwe_product(
100        module.n() as f64,
101        basek,
102        0.5,
103        0.5,
104        1.0 / 12.0,
105        sigma * sigma,
106        0.0,
107        rank as f64,
108        k,
109        k_autokey,
110    );
111    noise_want += sigma * sigma * (-2.0 * (k) as f64).exp2();
112    noise_want += module.n() as f64 * 1.0 / 12.0 * 0.5 * rank as f64 * (-2.0 * (k) as f64).exp2();
113    noise_want = noise_want.sqrt().log2();
114
115    assert!((noise_have - noise_want).abs() < 1.0);
116}