use base2k::{
    Decoding, Encoding, FFT64, FillUniform, Module, ScalarZnx, ScalarZnxAlloc, ScratchOwned, Stats, VecZnxOps, VecZnxToMut,
    ZnxViewMut, ZnxZero,
};
use itertools::izip;
use sampling::source::Source;

use crate::{
    elem::Infos,
    ggsw_ciphertext::GGSWCiphertext,
    glwe_ciphertext::GLWECiphertext,
    glwe_ciphertext_fourier::GLWECiphertextFourier,
    glwe_plaintext::GLWEPlaintext,
    keys::{GLWEPublicKey, SecretKey, SecretKeyFourier},
    keyswitch_key::GLWESwitchingKey,
    test_fft64::{gglwe::noise_grlwe_rlwe_product, ggsw::noise_rgsw_product},
};

#[test]
fn encrypt_sk() {
    let module: Module<FFT64> = Module::<FFT64>::new(32);
    let log_base2k: usize = 8;
    let log_k_ct: usize = 54;
    let log_k_pt: usize = 30;
    let rank: usize = 1;

    let sigma: f64 = 3.2;
    let bound: f64 = sigma * 6.0;

    let mut ct: GLWECiphertext<Vec<u8>> = GLWECiphertext::new(&module, log_base2k, log_k_ct, rank);
    let mut pt: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::new(&module, log_base2k, log_k_pt);

    let mut source_xs: Source = Source::new([0u8; 32]);
    let mut source_xe: Source = Source::new([0u8; 32]);
    let mut source_xa: Source = Source::new([0u8; 32]);

    let mut scratch: ScratchOwned = ScratchOwned::new(
        GLWECiphertext::encrypt_sk_scratch_space(&module, rank, ct.size())
            | GLWECiphertext::decrypt_scratch_space(&module, ct.size()),
    );

    let mut sk: SecretKey<Vec<u8>> = SecretKey::new(&module, rank);
    sk.fill_ternary_prob(0.5, &mut source_xs);

    let mut sk_dft: SecretKeyFourier<Vec<u8>, FFT64> = SecretKeyFourier::new(&module, rank);
    sk_dft.dft(&module, &sk);

    let mut data_want: Vec<i64> = vec![0i64; module.n()];

    data_want
        .iter_mut()
        .for_each(|x| *x = source_xa.next_i64() & 0xFF);

    pt.data
        .encode_vec_i64(0, log_base2k, log_k_pt, &data_want, 10);

    ct.encrypt_sk(
        &module,
        &pt,
        &sk_dft,
        &mut source_xa,
        &mut source_xe,
        sigma,
        bound,
        scratch.borrow(),
    );

    pt.data.zero();

    ct.decrypt(&module, &mut pt, &sk_dft, scratch.borrow());

    let mut data_have: Vec<i64> = vec![0i64; module.n()];

    pt.data
        .decode_vec_i64(0, log_base2k, pt.size() * log_base2k, &mut data_have);

    // TODO: properly assert the decryption noise through std(dec(ct) - pt)
    let scale: f64 = (1 << (pt.size() * log_base2k - log_k_pt)) as f64;
    izip!(data_want.iter(), data_have.iter()).for_each(|(a, b)| {
        let b_scaled = (*b as f64) / scale;
        assert!(
            (*a as f64 - b_scaled).abs() < 0.1,
            "{} {}",
            *a as f64,
            b_scaled
        )
    });
}

#[test]
fn encrypt_zero_sk() {
    let module: Module<FFT64> = Module::<FFT64>::new(1024);
    let log_base2k: usize = 8;
    let log_k_ct: usize = 55;
    let rank: usize = 1;

    let sigma: f64 = 3.2;
    let bound: f64 = sigma * 6.0;

    let mut pt: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::new(&module, log_base2k, log_k_ct);

    let mut source_xs: Source = Source::new([0u8; 32]);
    let mut source_xe: Source = Source::new([1u8; 32]);
    let mut source_xa: Source = Source::new([0u8; 32]);

    let mut sk: SecretKey<Vec<u8>> = SecretKey::new(&module, rank);
    sk.fill_ternary_prob(0.5, &mut source_xs);
    let mut sk_dft: SecretKeyFourier<Vec<u8>, FFT64> = SecretKeyFourier::new(&module, rank);
    sk_dft.dft(&module, &sk);

    let mut ct_dft: GLWECiphertextFourier<Vec<u8>, FFT64> = GLWECiphertextFourier::new(&module, log_base2k, log_k_ct, rank);

    let mut scratch: ScratchOwned = ScratchOwned::new(
        GLWECiphertextFourier::decrypt_scratch_space(&module, ct_dft.size())
            | GLWECiphertextFourier::encrypt_sk_scratch_space(&module, rank, ct_dft.size()),
    );

    ct_dft.encrypt_zero_sk(
        &module,
        &sk_dft,
        &mut source_xa,
        &mut source_xe,
        sigma,
        bound,
        scratch.borrow(),
    );
    ct_dft.decrypt(&module, &mut pt, &sk_dft, scratch.borrow());

    assert!((sigma - pt.data.std(0, log_base2k) * (log_k_ct as f64).exp2()) <= 0.2);
}

#[test]
fn encrypt_pk() {
    let module: Module<FFT64> = Module::<FFT64>::new(32);
    let log_base2k: usize = 8;
    let log_k_ct: usize = 54;
    let log_k_pk: usize = 64;
    let rank: usize = 1;

    let sigma: f64 = 3.2;
    let bound: f64 = sigma * 6.0;

    let mut ct: GLWECiphertext<Vec<u8>> = GLWECiphertext::new(&module, log_base2k, log_k_ct, rank);
    let mut pt_want: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::new(&module, log_base2k, log_k_ct);

    let mut source_xs: Source = Source::new([0u8; 32]);
    let mut source_xe: Source = Source::new([0u8; 32]);
    let mut source_xa: Source = Source::new([0u8; 32]);
    let mut source_xu: Source = Source::new([0u8; 32]);

    let mut sk: SecretKey<Vec<u8>> = SecretKey::new(&module, rank);
    sk.fill_ternary_prob(0.5, &mut source_xs);
    let mut sk_dft: SecretKeyFourier<Vec<u8>, FFT64> = SecretKeyFourier::new(&module, rank);
    sk_dft.dft(&module, &sk);

    let mut pk: GLWEPublicKey<Vec<u8>, FFT64> = GLWEPublicKey::new(&module, log_base2k, log_k_pk, rank);
    pk.generate(
        &module,
        &sk_dft,
        &mut source_xa,
        &mut source_xe,
        sigma,
        bound,
    );

    let mut scratch: ScratchOwned = ScratchOwned::new(
        GLWECiphertext::encrypt_sk_scratch_space(&module, rank, ct.size())
            | GLWECiphertext::decrypt_scratch_space(&module, ct.size())
            | GLWECiphertext::encrypt_pk_scratch_space(&module, rank, pk.size()),
    );

    let mut data_want: Vec<i64> = vec![0i64; module.n()];

    data_want
        .iter_mut()
        .for_each(|x| *x = source_xa.next_i64() & 0);

    pt_want
        .data
        .encode_vec_i64(0, log_base2k, log_k_ct, &data_want, 10);

    ct.encrypt_pk(
        &module,
        &pt_want,
        &pk,
        &mut source_xu,
        &mut source_xe,
        sigma,
        bound,
        scratch.borrow(),
    );

    let mut pt_have: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::new(&module, log_base2k, log_k_ct);

    ct.decrypt(&module, &mut pt_have, &sk_dft, scratch.borrow());

    module.vec_znx_sub_ab_inplace(&mut pt_want, 0, &pt_have, 0);

    assert!(((1.0f64 / 12.0).sqrt() - pt_want.data.std(0, log_base2k) * (log_k_ct as f64).exp2()).abs() < 0.2);
}

#[test]
fn keyswitch() {
    let module: Module<FFT64> = Module::<FFT64>::new(2048);
    let log_base2k: usize = 12;
    let log_k_grlwe: usize = 60;
    let log_k_rlwe_in: usize = 45;
    let log_k_rlwe_out: usize = 60;
    let rows: usize = (log_k_rlwe_in + log_base2k - 1) / log_base2k;
    let rank: usize = 1;

    let sigma: f64 = 3.2;
    let bound: f64 = sigma * 6.0;

    let mut ct_grlwe: GLWESwitchingKey<Vec<u8>, FFT64> =
        GLWESwitchingKey::new(&module, log_base2k, log_k_grlwe, rows, rank, rank);
    let mut ct_rlwe_in: GLWECiphertext<Vec<u8>> = GLWECiphertext::new(&module, log_base2k, log_k_rlwe_in, rank);
    let mut ct_rlwe_out: GLWECiphertext<Vec<u8>> = GLWECiphertext::new(&module, log_base2k, log_k_rlwe_out, rank);
    let mut pt_want: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::new(&module, log_base2k, log_k_rlwe_in);
    let mut pt_have: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::new(&module, log_base2k, log_k_rlwe_out);

    let mut source_xs: Source = Source::new([0u8; 32]);
    let mut source_xe: Source = Source::new([0u8; 32]);
    let mut source_xa: Source = Source::new([0u8; 32]);

    // Random input plaintext
    pt_want
        .data
        .fill_uniform(log_base2k, 0, pt_want.size(), &mut source_xa);

    let mut scratch: ScratchOwned = ScratchOwned::new(
        GLWESwitchingKey::encrypt_sk_scratch_space(&module, rank, ct_grlwe.size())
            | GLWECiphertext::decrypt_scratch_space(&module, ct_rlwe_out.size())
            | GLWECiphertext::encrypt_sk_scratch_space(&module, rank, ct_rlwe_in.size())
            | GLWECiphertext::keyswitch_scratch_space(
                &module,
                ct_rlwe_out.size(),
                ct_rlwe_in.size(),
                ct_grlwe.size(),
            ),
    );

    let mut sk0: SecretKey<Vec<u8>> = SecretKey::new(&module, rank);
    sk0.fill_ternary_prob(0.5, &mut source_xs);

    let mut sk0_dft: SecretKeyFourier<Vec<u8>, FFT64> = SecretKeyFourier::new(&module, rank);
    sk0_dft.dft(&module, &sk0);

    let mut sk1: SecretKey<Vec<u8>> = SecretKey::new(&module, rank);
    sk1.fill_ternary_prob(0.5, &mut source_xs);

    let mut sk1_dft: SecretKeyFourier<Vec<u8>, FFT64> = SecretKeyFourier::new(&module, rank);
    sk1_dft.dft(&module, &sk1);

    ct_grlwe.encrypt_sk(
        &module,
        &sk0.data,
        &sk1_dft,
        &mut source_xa,
        &mut source_xe,
        sigma,
        bound,
        scratch.borrow(),
    );

    ct_rlwe_in.encrypt_sk(
        &module,
        &pt_want,
        &sk0_dft,
        &mut source_xa,
        &mut source_xe,
        sigma,
        bound,
        scratch.borrow(),
    );

    ct_rlwe_out.keyswitch(&module, &ct_rlwe_in, &ct_grlwe, scratch.borrow());

    ct_rlwe_out.decrypt(&module, &mut pt_have, &sk1_dft, scratch.borrow());

    module.vec_znx_sub_ab_inplace(&mut pt_have, 0, &pt_want, 0);

    let noise_have: f64 = pt_have.data.std(0, log_base2k).log2();
    let noise_want: f64 = noise_grlwe_rlwe_product(
        module.n() as f64,
        log_base2k,
        0.5,
        0.5,
        0f64,
        sigma * sigma,
        0f64,
        log_k_rlwe_in,
        log_k_grlwe,
    );

    assert!(
        (noise_have - noise_want).abs() <= 0.1,
        "{} {}",
        noise_have,
        noise_want
    );
}

#[test]
fn keyswich_inplace() {
    let module: Module<FFT64> = Module::<FFT64>::new(2048);
    let log_base2k: usize = 12;
    let log_k_grlwe: usize = 60;
    let log_k_rlwe: usize = 45;
    let rows: usize = (log_k_rlwe + log_base2k - 1) / log_base2k;
    let rank: usize = 1;

    let sigma: f64 = 3.2;
    let bound: f64 = sigma * 6.0;

    let mut ct_grlwe: GLWESwitchingKey<Vec<u8>, FFT64> =
        GLWESwitchingKey::new(&module, log_base2k, log_k_grlwe, rows, rank, rank);
    let mut ct_rlwe: GLWECiphertext<Vec<u8>> = GLWECiphertext::new(&module, log_base2k, log_k_rlwe, rank);
    let mut pt_want: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::new(&module, log_base2k, log_k_rlwe);
    let mut pt_have: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::new(&module, log_base2k, log_k_rlwe);

    let mut source_xs: Source = Source::new([0u8; 32]);
    let mut source_xe: Source = Source::new([0u8; 32]);
    let mut source_xa: Source = Source::new([0u8; 32]);

    // Random input plaintext
    pt_want
        .data
        .fill_uniform(log_base2k, 0, pt_want.size(), &mut source_xa);

    let mut scratch: ScratchOwned = ScratchOwned::new(
        GLWESwitchingKey::encrypt_sk_scratch_space(&module, rank, ct_grlwe.size())
            | GLWECiphertext::decrypt_scratch_space(&module, ct_rlwe.size())
            | GLWECiphertext::encrypt_sk_scratch_space(&module, rank, ct_rlwe.size())
            | GLWECiphertext::keyswitch_inplace_scratch_space(&module, ct_rlwe.size(), ct_grlwe.size()),
    );

    let mut sk0: SecretKey<Vec<u8>> = SecretKey::new(&module, rank);
    sk0.fill_ternary_prob(0.5, &mut source_xs);

    let mut sk0_dft: SecretKeyFourier<Vec<u8>, FFT64> = SecretKeyFourier::new(&module, rank);
    sk0_dft.dft(&module, &sk0);

    let mut sk1: SecretKey<Vec<u8>> = SecretKey::new(&module, rank);
    sk1.fill_ternary_prob(0.5, &mut source_xs);

    let mut sk1_dft: SecretKeyFourier<Vec<u8>, FFT64> = SecretKeyFourier::new(&module, rank);
    sk1_dft.dft(&module, &sk1);

    ct_grlwe.encrypt_sk(
        &module,
        &sk0.data,
        &sk1_dft,
        &mut source_xa,
        &mut source_xe,
        sigma,
        bound,
        scratch.borrow(),
    );

    ct_rlwe.encrypt_sk(
        &module,
        &pt_want,
        &sk0_dft,
        &mut source_xa,
        &mut source_xe,
        sigma,
        bound,
        scratch.borrow(),
    );

    ct_rlwe.keyswitch_inplace(&module, &ct_grlwe, scratch.borrow());

    ct_rlwe.decrypt(&module, &mut pt_have, &sk1_dft, scratch.borrow());

    module.vec_znx_sub_ab_inplace(&mut pt_have, 0, &pt_want, 0);

    let noise_have: f64 = pt_have.data.std(0, log_base2k).log2();
    let noise_want: f64 = noise_grlwe_rlwe_product(
        module.n() as f64,
        log_base2k,
        0.5,
        0.5,
        0f64,
        sigma * sigma,
        0f64,
        log_k_rlwe,
        log_k_grlwe,
    );

    assert!(
        (noise_have - noise_want).abs() <= 0.1,
        "{} {}",
        noise_have,
        noise_want
    );
}

#[test]
fn external_product() {
    let module: Module<FFT64> = Module::<FFT64>::new(2048);
    let log_base2k: usize = 12;
    let log_k_grlwe: usize = 60;
    let log_k_rlwe_in: usize = 45;
    let log_k_rlwe_out: usize = 60;
    let rows: usize = (log_k_rlwe_in + log_base2k - 1) / log_base2k;
    let rank: usize = 1;

    let sigma: f64 = 3.2;
    let bound: f64 = sigma * 6.0;

    let mut ct_rgsw: GGSWCiphertext<Vec<u8>, FFT64> = GGSWCiphertext::new(&module, log_base2k, log_k_grlwe, rows, rank);
    let mut ct_rlwe_in: GLWECiphertext<Vec<u8>> = GLWECiphertext::new(&module, log_base2k, log_k_rlwe_in, rank);
    let mut ct_rlwe_out: GLWECiphertext<Vec<u8>> = GLWECiphertext::new(&module, log_base2k, log_k_rlwe_out, rank);
    let mut pt_rgsw: ScalarZnx<Vec<u8>> = module.new_scalar_znx(1);
    let mut pt_want: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::new(&module, log_base2k, log_k_rlwe_in);
    let mut pt_have: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::new(&module, log_base2k, log_k_rlwe_out);

    let mut source_xs: Source = Source::new([0u8; 32]);
    let mut source_xe: Source = Source::new([0u8; 32]);
    let mut source_xa: Source = Source::new([0u8; 32]);

    // Random input plaintext
    pt_want
        .data
        .fill_uniform(log_base2k, 0, pt_want.size(), &mut source_xa);

    pt_want.to_mut().at_mut(0, 0)[1] = 1;

    let k: usize = 1;

    pt_rgsw.raw_mut()[k] = 1; // X^{k}

    let mut scratch: ScratchOwned = ScratchOwned::new(
        GGSWCiphertext::encrypt_sk_scratch_space(&module, rank, ct_rgsw.size())
            | GLWECiphertext::decrypt_scratch_space(&module, ct_rlwe_out.size())
            | GLWECiphertext::encrypt_sk_scratch_space(&module, rank, ct_rlwe_in.size())
            | GLWECiphertext::external_product_scratch_space(
                &module,
                ct_rlwe_out.size(),
                ct_rlwe_in.size(),
                ct_rgsw.size(),
            ),
    );

    let mut sk: SecretKey<Vec<u8>> = SecretKey::new(&module, rank);
    sk.fill_ternary_prob(0.5, &mut source_xs);

    let mut sk_dft: SecretKeyFourier<Vec<u8>, FFT64> = SecretKeyFourier::new(&module, rank);
    sk_dft.dft(&module, &sk);

    ct_rgsw.encrypt_sk(
        &module,
        &pt_rgsw,
        &sk_dft,
        &mut source_xa,
        &mut source_xe,
        sigma,
        bound,
        scratch.borrow(),
    );

    ct_rlwe_in.encrypt_sk(
        &module,
        &pt_want,
        &sk_dft,
        &mut source_xa,
        &mut source_xe,
        sigma,
        bound,
        scratch.borrow(),
    );

    ct_rlwe_out.external_product(&module, &ct_rlwe_in, &ct_rgsw, scratch.borrow());

    ct_rlwe_out.decrypt(&module, &mut pt_have, &sk_dft, scratch.borrow());

    module.vec_znx_rotate_inplace(k as i64, &mut pt_want, 0);

    module.vec_znx_sub_ab_inplace(&mut pt_have, 0, &pt_want, 0);

    let noise_have: f64 = pt_have.data.std(0, log_base2k).log2();

    let var_gct_err_lhs: f64 = sigma * sigma;
    let var_gct_err_rhs: f64 = 0f64;

    let var_msg: f64 = 1f64 / module.n() as f64; // X^{k}
    let var_a0_err: f64 = sigma * sigma;
    let var_a1_err: f64 = 1f64 / 12f64;

    let noise_want: f64 = noise_rgsw_product(
        module.n() as f64,
        log_base2k,
        0.5,
        var_msg,
        var_a0_err,
        var_a1_err,
        var_gct_err_lhs,
        var_gct_err_rhs,
        log_k_rlwe_in,
        log_k_grlwe,
    );

    assert!(
        (noise_have - noise_want).abs() <= 0.1,
        "{} {}",
        noise_have,
        noise_want
    );
}

#[test]
fn external_product_inplace() {
    let module: Module<FFT64> = Module::<FFT64>::new(2048);
    let log_base2k: usize = 12;
    let log_k_grlwe: usize = 60;
    let log_k_rlwe_in: usize = 45;
    let log_k_rlwe_out: usize = 60;
    let rows: usize = (log_k_rlwe_in + log_base2k - 1) / log_base2k;
    let rank: usize = 1;

    let sigma: f64 = 3.2;
    let bound: f64 = sigma * 6.0;

    let mut ct_rgsw: GGSWCiphertext<Vec<u8>, FFT64> = GGSWCiphertext::new(&module, log_base2k, log_k_grlwe, rows, rank);
    let mut ct_rlwe: GLWECiphertext<Vec<u8>> = GLWECiphertext::new(&module, log_base2k, log_k_rlwe_in, rank);
    let mut pt_rgsw: ScalarZnx<Vec<u8>> = module.new_scalar_znx(1);
    let mut pt_want: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::new(&module, log_base2k, log_k_rlwe_in);
    let mut pt_have: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::new(&module, log_base2k, log_k_rlwe_out);

    let mut source_xs: Source = Source::new([0u8; 32]);
    let mut source_xe: Source = Source::new([0u8; 32]);
    let mut source_xa: Source = Source::new([0u8; 32]);

    // Random input plaintext
    pt_want
        .data
        .fill_uniform(log_base2k, 0, pt_want.size(), &mut source_xa);

    pt_want.to_mut().at_mut(0, 0)[1] = 1;

    let k: usize = 1;

    pt_rgsw.raw_mut()[k] = 1; // X^{k}

    let mut scratch: ScratchOwned = ScratchOwned::new(
        GGSWCiphertext::encrypt_sk_scratch_space(&module, rank, ct_rgsw.size())
            | GLWECiphertext::decrypt_scratch_space(&module, ct_rlwe.size())
            | GLWECiphertext::encrypt_sk_scratch_space(&module, rank, ct_rlwe.size())
            | GLWECiphertext::external_product_inplace_scratch_space(&module, ct_rlwe.size(), ct_rgsw.size()),
    );

    let mut sk: SecretKey<Vec<u8>> = SecretKey::new(&module, rank);
    sk.fill_ternary_prob(0.5, &mut source_xs);

    let mut sk_dft: SecretKeyFourier<Vec<u8>, FFT64> = SecretKeyFourier::new(&module, rank);
    sk_dft.dft(&module, &sk);

    ct_rgsw.encrypt_sk(
        &module,
        &pt_rgsw,
        &sk_dft,
        &mut source_xa,
        &mut source_xe,
        sigma,
        bound,
        scratch.borrow(),
    );

    ct_rlwe.encrypt_sk(
        &module,
        &pt_want,
        &sk_dft,
        &mut source_xa,
        &mut source_xe,
        sigma,
        bound,
        scratch.borrow(),
    );

    ct_rlwe.external_product_inplace(&module, &ct_rgsw, scratch.borrow());

    ct_rlwe.decrypt(&module, &mut pt_have, &sk_dft, scratch.borrow());

    module.vec_znx_rotate_inplace(k as i64, &mut pt_want, 0);

    module.vec_znx_sub_ab_inplace(&mut pt_have, 0, &pt_want, 0);

    let noise_have: f64 = pt_have.data.std(0, log_base2k).log2();

    let var_gct_err_lhs: f64 = sigma * sigma;
    let var_gct_err_rhs: f64 = 0f64;

    let var_msg: f64 = 1f64 / module.n() as f64; // X^{k}
    let var_a0_err: f64 = sigma * sigma;
    let var_a1_err: f64 = 1f64 / 12f64;

    let noise_want: f64 = noise_rgsw_product(
        module.n() as f64,
        log_base2k,
        0.5,
        var_msg,
        var_a0_err,
        var_a1_err,
        var_gct_err_lhs,
        var_gct_err_rhs,
        log_k_rlwe_in,
        log_k_grlwe,
    );

    assert!(
        (noise_have - noise_want).abs() <= 0.1,
        "{} {}",
        noise_have,
        noise_want
    );
}