/*
    Copyright (C) 2008, 2009 William Hart
    Copyright (C) 2012 Sebastian Pancratz
    Copyright (C) 2013 Mike Hansen

    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/>.
*/

#ifdef T

#include "templates.h"

void
_TEMPLATE3(T, poly_scalar_submul, T) (TEMPLATE(T, struct) * rop,
                                      const TEMPLATE(T, struct) * op, slong len,
                                      const TEMPLATE(T, t) x,
                                      const TEMPLATE(T, ctx_t) ctx)
{
    if (TEMPLATE(T, is_zero) (x, ctx))
        return;

    if (TEMPLATE(T, is_one) (x, ctx))
    {
        _TEMPLATE(T, poly_sub) (rop, rop, len, op, len, ctx);
    }
    else
    {
        slong i;
        TEMPLATE(T, t) t;

        TEMPLATE(T, init) (t, ctx);

        for (i = 0; i < len; i++)
        {
            TEMPLATE(T, mul) (t, op + i, x, ctx);
            TEMPLATE(T, sub) (rop + i, rop + i, t, ctx);
        }

        TEMPLATE(T, clear) (t, ctx);
    }
}

void
TEMPLATE3(T, poly_scalar_submul, T) (TEMPLATE(T, poly_t) rop,
                                     const TEMPLATE(T, poly_t) op,
                                     const TEMPLATE(T, t) x,
                                     const TEMPLATE(T, ctx_t) ctx)
{
    if (!
        (TEMPLATE(T, is_zero) (x, ctx) || TEMPLATE(T, poly_is_zero) (op, ctx)))
    {
        TEMPLATE(T, poly_fit_length) (rop, op->length, ctx);
        if (op->length > rop->length)
            _TEMPLATE(T, vec_zero) (rop->coeffs + rop->length,
			            op->length - rop->length, ctx);
        _TEMPLATE3(T, poly_scalar_submul, T) (rop->coeffs, op->coeffs,
                                              op->length, x, ctx);
        _TEMPLATE(T, poly_set_length) (rop, FLINT_MAX(rop->length, op->length),
                                       ctx);
        _TEMPLATE(T, poly_normalise) (rop, ctx);
    }
}


#endif
