/*
    Copyright (C) 2015 Vladimir Glazachev

    This file is part of FLINT.

    FLINT is free software: you can redistribute it and/or modify it under
    the terms of the GNU Lesser General Public License (LGPL) as published
    by the Free Software Foundation; either version 2.1 of the License, or
    (at your option) any later version.  See <https://www.gnu.org/licenses/>.
*/

#include "aprcl.h"

void
unity_zp_sqr(unity_zp f, const unity_zp g)
{
    if (g->poly->length == 0)
    {
        fmpz_mod_poly_zero(f->poly, f->ctx);
        return;
    }

    fmpz_mod_poly_fit_length(f->poly, g->poly->length * 2 - 1, f->ctx);

    _fmpz_poly_sqr(f->poly->coeffs, g->poly->coeffs, g->poly->length);
    _fmpz_mod_poly_set_length(f->poly, 2 * g->poly->length - 1);

    _unity_zp_reduce_cyclotomic_divmod(f);
}

void
unity_zp_sqr_inplace(unity_zp f, const unity_zp g, fmpz_t * t)
{
    /* squaring for p^k = 4 */
    if (f->p == 2 && f->exp == 2)
    {
        unity_zp_sqr4(f, g, t);
        return;
    }

    /* squaring for p^k = 8 */
    if (f->p == 2 && f->exp == 3)
    {
        unity_zp_sqr8(f, g, t);
        return;
    }

    /* squaring for p^k = 16 */
    if (f->p == 2 && f->exp == 4)
    {
        unity_zp_sqr16(f, g, t);
        return;
    }

    /* squaring for p^k = 3 */
    if (f->p == 3 && f->exp == 1)
    {
        unity_zp_sqr3(f, g, t);
        return;
    }

    /* squaring for p^k = 9 */
    if (f->p == 3 && f->exp == 2)
    {
        unity_zp_sqr9(f, g, t);
        return;
    }

    /* squaring for p^k = 5 */
    if (f->p == 5 && f->exp == 1)
    {
        unity_zp_sqr5(f, g, t);
        return;
    }

    /* squaring for p^k = 7 */
    if (f->p == 7 && f->exp == 1)
    {
        unity_zp_sqr7(f, g, t);
        return;
    }

    /* squaring for p^k = 11 */
    if (f->p == 11 && f->exp == 1)
    {
        unity_zp_sqr11(f, g, t);
        return;
    }

    /* traditional squaring */
    unity_zp_sqr(f, g);      
}