use ark_ec::{
    models::CurveConfig,
    twisted_edwards::{Affine, MontCurveConfig, Projective, TECurveConfig},
};
use ark_ff::MontFp;

use crate::{fq::Fq, fr::Fr};

#[cfg(test)]
mod tests;

pub type EdwardsAffine = Affine<EdwardsConfig>;
pub type EdwardsProjective = Projective<EdwardsConfig>;

#[derive(Clone, Default, PartialEq, Eq)]
pub struct EdwardsConfig;

impl CurveConfig for EdwardsConfig {
    type BaseField = Fq;
    type ScalarField = Fr;

    /// COFACTOR = 4
    const COFACTOR: &'static [u64] = &[4];

    /// COFACTOR_INV =
    /// 527778859339273151515551558673846658209717731602102048798421311598680340096
    const COFACTOR_INV: Fr =
        MontFp!("527778859339273151515551558673846658209717731602102048798421311598680340096");
}

impl TECurveConfig for EdwardsConfig {
    /// COEFF_A = -1
    const COEFF_A: Fq = MontFp!("-1");

    /// COEFF_D = 3021
    const COEFF_D: Fq = MontFp!("3021");

    /// Generated randomly
    const GENERATOR: EdwardsAffine = EdwardsAffine::new_unchecked(GENERATOR_X, GENERATOR_Y);

    type MontCurveConfig = EdwardsConfig;

    /// Multiplication by `a` is just negation.
    /// Is `a` 1 or -1?
    #[inline(always)]
    fn mul_by_a(elem: Self::BaseField) -> Self::BaseField {
        -elem
    }
}

impl MontCurveConfig for EdwardsConfig {
    /// COEFF_A = 0x8D26E3FADA9010A26949031ECE3971B93952AD84D4753DDEDB748DA37E8F552
    ///         = 3990301581132929505568273333084066329187552697088022219156688740916631500114
    const COEFF_A: Fq =
        MontFp!("3990301581132929505568273333084066329187552697088022219156688740916631500114");

    /// COEFF_B = 0x9D8F71EEC83A44C3A1FBCEC6F5418E5C6154C2682B8AC231C5A3725C8170AAD
    ///         = 4454160168295440918680551605697480202188346638066041608778544715000777738925
    const COEFF_B: Fq =
        MontFp!("4454160168295440918680551605697480202188346638066041608778544715000777738925");

    type TECurveConfig = EdwardsConfig;
}

/// GENERATOR_X =
/// 4497879464030519973909970603271755437257548612157028181994697785683032656389,
pub const GENERATOR_X: Fq =
    MontFp!("4497879464030519973909970603271755437257548612157028181994697785683032656389");

/// GENERATOR_Y =
/// 4357141146396347889246900916607623952598927460421559113092863576544024487809
pub const GENERATOR_Y: Fq =
    MontFp!("4357141146396347889246900916607623952598927460421559113092863576544024487809");