/*
    Copyright (C) 2009 William Hart
    Copyright (C) 2010 Sebastian Pancratz

    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 3 of the License, or
    (at your option) any later version.  See <https://www.gnu.org/licenses/>.
*/

#include "test_helpers.h"
#include "fmpz.h"
#include "fmpz_poly.h"
#include "ulong_extras.h"

TEST_FUNCTION_START(fmpz_poly_scalar_submul_fmpz, state)
{
    int i, result;

    /* Check aliasing of a and b */
    for (i = 0; i < 1000 * flint_test_multiplier(); i++)
    {
        fmpz_poly_t a, b, c;
        fmpz_t x;

        fmpz_init(x);
        fmpz_poly_init(a);
        fmpz_poly_init(b);
        fmpz_poly_init(c);
        fmpz_randtest(x, state, n_randint(state, 100));
        fmpz_poly_randtest(a, state, n_randint(state, 100), 200);
        fmpz_poly_set(b, a);
        fmpz_poly_set(c, a);

        fmpz_poly_scalar_submul_fmpz(b, a, x);
        fmpz_poly_scalar_submul_fmpz(a, a, x);

        result = (fmpz_poly_equal(a, b));
        if (!result)
        {
            flint_printf("FAIL (1):\n");
            flint_printf("a = "), fmpz_poly_print(a), flint_printf("\n\n");
            flint_printf("b = "), fmpz_poly_print(b), flint_printf("\n\n");
            flint_printf("c = "), fmpz_poly_print(c), flint_printf("\n\n");
            flint_printf("x = "), fmpz_print(x), flint_printf("\n\n");
            fflush(stdout);
            flint_abort();
        }

        fmpz_clear(x);
        fmpz_poly_clear(a);
        fmpz_poly_clear(b);
        fmpz_poly_clear(c);
    }

    /* Check that b += x*a is the same as c = b + x*a */
    for (i = 0; i < 1000 * flint_test_multiplier(); i++)
    {
        fmpz_poly_t a, b, c;
        fmpz_t x;

        fmpz_init(x);
        fmpz_poly_init(a);
        fmpz_poly_init(b);
        fmpz_poly_init(c);
        fmpz_randtest(x, state, n_randint(state, 100));
        fmpz_poly_randtest(a, state, n_randint(state, 100), 200);
        fmpz_poly_randtest(b, state, n_randint(state, 100), 200);

        fmpz_poly_scalar_mul_fmpz(c, a, x);
        fmpz_poly_sub(c, b, c);

        fmpz_poly_scalar_submul_fmpz(b, a, x);

        result = (fmpz_poly_equal(b, c));
        if (!result)
        {
            flint_printf("FAIL (2):\n");
            flint_printf("a = "), fmpz_poly_print(a), flint_printf("\n\n");
            flint_printf("b = "), fmpz_poly_print(b), flint_printf("\n\n");
            flint_printf("c = "), fmpz_poly_print(c), flint_printf("\n\n");
            flint_printf("x = "), fmpz_print(x), flint_printf("\n\n");
            fflush(stdout);
            flint_abort();
        }

        fmpz_clear(x);
        fmpz_poly_clear(a);
        fmpz_poly_clear(b);
        fmpz_poly_clear(c);
    }

    TEST_FUNCTION_END(state);
}
