def dup_sqf_part(f, K):
    """
    Returns square-free part of a polynomial in ``K[x]``.

    Examples
    ========

    >>> from sympy.polys import ring, ZZ
    >>> R, x = ring("x", ZZ)

    >>> R.dup_sqf_part(x**3 - 3*x - 2)
    x**2 - x - 2

    """
    if K.is_FiniteField:
        return dup_gf_sqf_part(f, K)

    if not f:
        return f

    if K.is_negative(dup_LC(f, K)):
        f = dup_neg(f, K)

    gcd = dup_gcd(f, dup_diff(f, 1, K), K)
    sqf = dup_quo(f, gcd, K)

    if K.has_Field:
        return dup_monic(sqf, K)
    else:
        return dup_primitive(sqf, K)[1]

def dup_sqf_part(f, K):
    """
    Returns square-free part of a polynomial in ``K[x]``.

    Examples
    ========

    >>> from sympy.polys.domains import ZZ
    >>> from sympy.polys.sqfreetools import dup_sqf_part

    >>> dup_sqf_part([ZZ(1), ZZ(0), -ZZ(3), -ZZ(2)], ZZ)
    [1, -1, -2]

    """
    if not K.has_CharacteristicZero:
        return dup_gf_sqf_part(f, K)

    if not f:
        return f

    if K.is_negative(dup_LC(f, K)):
        f = dup_neg(f, K)

    gcd = dup_gcd(f, dup_diff(f, 1, K), K)
    sqf = dup_quo(f, gcd, K)

    if K.has_Field or not K.is_Exact:
        return dup_monic(sqf, K)
    else:
        return dup_primitive(sqf, K)[1]

def dup_zz_factor_sqf(f, K):
    """Factor square-free (non-primitive) polyomials in `Z[x]`. """
    cont, g = dup_primitive(f, K)

    n = dup_degree(g)

    if dup_LC(g, K) < 0:
        cont, g = -cont, dup_neg(g, K)

    if n <= 0:
        return cont, []
    elif n == 1:
        return cont, [(g, 1)]

    if query('USE_IRREDUCIBLE_IN_FACTOR'):
        if dup_zz_irreducible_p(g, K):
            return cont, [(g, 1)]

    factors = None

    if query('USE_CYCLOTOMIC_FACTOR'):
        factors = dup_zz_cyclotomic_factor(g, K)

    if factors is None:
        factors = dup_zz_zassenhaus(g, K)

    return cont, _sort_factors(factors, multiple=False)

def _dup_rr_trivial_gcd(f, g, K):
    """Handle trivial cases in GCD algorithm over a ring. """
    if not (f or g):
        return [], [], []
    elif not f:
        if K.is_nonnegative(dup_LC(g, K)):
            return g, [], [K.one]
        else:
            return dup_neg(g, K), [], [-K.one]
    elif not g:
        if K.is_nonnegative(dup_LC(f, K)):
            return f, [K.one], []
        else:
            return dup_neg(f, K), [-K.one], []

    return None

def test_dup_neg():
    assert dup_neg([], ZZ) == []
    assert dup_neg([ZZ(1)], ZZ) == [ZZ(-1)]
    assert dup_neg([ZZ(-7)], ZZ) == [ZZ(7)]
    assert dup_neg([ZZ(-1),ZZ(2),ZZ(3)], ZZ) == [ZZ(1),ZZ(-2),ZZ(-3)]

    assert dup_neg([], QQ) == []
    assert dup_neg([QQ(1,2)], QQ) == [QQ(-1,2)]
    assert dup_neg([QQ(-7,9)], QQ) == [QQ(7,9)]
    assert dup_neg([QQ(-1,7),QQ(2,7),QQ(3,7)], QQ) == [QQ(1,7),QQ(-2,7),QQ(-3,7)]

def dup_sqf_list(f, K, all=False):
    """
    Return square-free decomposition of a polynomial in ``K[x]``.

    Examples
    ========

    >>> from sympy.polys.domains import ZZ
    >>> from sympy.polys.sqfreetools import dup_sqf_list

    >>> f = ZZ.map([2, 16, 50, 76, 56, 16])

    >>> dup_sqf_list(f, ZZ)
    (2, [([1, 1], 2), ([1, 2], 3)])

    >>> dup_sqf_list(f, ZZ, all=True)
    (2, [([1], 1), ([1, 1], 2), ([1, 2], 3)])

    """
    if not K.has_CharacteristicZero:
        return dup_gf_sqf_list(f, K, all=all)

    if K.has_Field or not K.is_Exact:
        coeff = dup_LC(f, K)
        f = dup_monic(f, K)
    else:
        coeff, f = dup_primitive(f, K)

        if K.is_negative(dup_LC(f, K)):
            f = dup_neg(f, K)
            coeff = -coeff

    if dup_degree(f) <= 0:
        return coeff, []

    result, i = [], 1

    h = dup_diff(f, 1, K)
    g, p, q = dup_inner_gcd(f, h, K)

    while True:
        d = dup_diff(p, 1, K)
        h = dup_sub(q, d, K)

        if not h:
            result.append((p, i))
            break

        g, p, q = dup_inner_gcd(p, h, K)

        if all or dup_degree(g) > 0:
            result.append((g, i))

        i += 1

    return coeff, result

def dup_sqf_list(f, K, all=False):
    """
    Return square-free decomposition of a polynomial in ``K[x]``.

    Examples
    ========

    >>> from sympy.polys import ring, ZZ
    >>> R, x = ring("x", ZZ)

    >>> f = 2*x**5 + 16*x**4 + 50*x**3 + 76*x**2 + 56*x + 16

    >>> R.dup_sqf_list(f)
    (2, [(x + 1, 2), (x + 2, 3)])
    >>> R.dup_sqf_list(f, all=True)
    (2, [(1, 1), (x + 1, 2), (x + 2, 3)])

    """
    if K.is_FiniteField:
        return dup_gf_sqf_list(f, K, all=all)

    if K.has_Field:
        coeff = dup_LC(f, K)
        f = dup_monic(f, K)
    else:
        coeff, f = dup_primitive(f, K)

        if K.is_negative(dup_LC(f, K)):
            f = dup_neg(f, K)
            coeff = -coeff

    if dup_degree(f) <= 0:
        return coeff, []

    result, i = [], 1

    h = dup_diff(f, 1, K)
    g, p, q = dup_inner_gcd(f, h, K)

    while True:
        d = dup_diff(p, 1, K)
        h = dup_sub(q, d, K)

        if not h:
            result.append((p, i))
            break

        g, p, q = dup_inner_gcd(p, h, K)

        if all or dup_degree(g) > 0:
            result.append((g, i))

        i += 1

    return coeff, result

def dmp_zz_wang_test_points(f, T, ct, A, u, K):
    """Wang/EEZ: Test evaluation points for suitability. """
    if not dmp_eval_tail(dmp_LC(f, K), A, u-1, K):
        raise EvaluationFailed('no luck')

    g = dmp_eval_tail(f, A, u, K)

    if not dup_sqf_p(g, K):
        raise EvaluationFailed('no luck')

    c, h = dup_primitive(g, K)

    if K.is_negative(dup_LC(h, K)):
        c, h = -c, dup_neg(h, K)

    v = u-1

    E = [ dmp_eval_tail(t, A, v, K) for t, _ in T ]
    D = dmp_zz_wang_non_divisors(E, c, ct, K)

    if D is not None:
        return c, h, E
    else:
        raise EvaluationFailed('no luck')

def dup_zz_factor_sqf(f, K, **args):
    """Factor square-free (non-primitive) polyomials in `Z[x]`. """
    cont, g = dup_primitive(f, K)

    n = dup_degree(g)

    if dup_LC(g, K) < 0:
        cont, g = -cont, dup_neg(g, K)

    if n <= 0:
        return cont, []

    if n == 1 or dup_zz_irreducible_p(g, K):
        return cont, [(g, 1)]

    factors = []

    if args.get('cyclotomic', True):
        factors = dup_zz_cyclotomic_factor(g, K)

    if factors is None:
        factors = dup_zz_zassenhaus(g, K)

    return cont, _sort_factors(factors, multiple=False)

def dup_zz_factor(f, K):
    """
    Factor (non square-free) polynomials in `Z[x]`.

    Given a univariate polynomial `f` in `Z[x]` computes its complete
    factorization `f_1, ..., f_n` into irreducibles over integers::

                f = content(f) f_1**k_1 ... f_n**k_n

    The factorization is computed by reducing the input polynomial
    into a primitive square-free polynomial and factoring it using
    Zassenhaus algorithm. Trial division is used to recover the
    multiplicities of factors.

    The result is returned as a tuple consisting of::

              (content(f), [(f_1, k_1), ..., (f_n, k_n))

    Consider polynomial `f = 2*x**4 - 2`::

        >>> from sympy.polys.factortools import dup_zz_factor
        >>> from sympy.polys.domains import ZZ

        >>> dup_zz_factor([2, 0, 0, 0, -2], ZZ)
        (2, [([1, -1], 1), ([1, 1], 1), ([1, 0, 1], 1)])

    In result we got the following factorization::

                 f = 2 (x - 1) (x + 1) (x**2 + 1)

    Note that this is a complete factorization over integers,
    however over Gaussian integers we can factor the last term.

    By default, polynomials `x**n - 1` and `x**n + 1` are factored
    using cyclotomic decomposition to speedup computations. To
    disable this behaviour set cyclotomic=False.

    **References**

    1. [Gathen99]_

    """
    cont, g = dup_primitive(f, K)

    n = dup_degree(g)

    if dup_LC(g, K) < 0:
        cont, g = -cont, dup_neg(g, K)

    if n <= 0:
        return cont, []
    elif n == 1:
        return cont, [(g, 1)]

    if query('USE_IRREDUCIBLE_IN_FACTOR'):
        if dup_zz_irreducible_p(g, K):
            return cont, [(g, 1)]

    g = dup_sqf_part(g, K)
    H, factors = None, []

    if query('USE_CYCLOTOMIC_FACTOR'):
        H = dup_zz_cyclotomic_factor(g, K)

    if H is None:
        H = dup_zz_zassenhaus(g, K)

    for h in H:
        k = 0

        while True:
            q, r = dup_div(f, h, K)

            if not r:
                f, k = q, k+1
            else:
                break

        factors.append((h, k))

    return cont, _sort_factors(factors)

def dup_zz_cyclotomic_p(f, K, irreducible=False):
    """
    Efficiently test if ``f`` is a cyclotomic polnomial.

    **Examples**

    >>> from sympy.polys.factortools import dup_zz_cyclotomic_p
    >>> from sympy.polys.domains import ZZ

    >>> f = [1, 0, 1, 0, 0, 0,-1, 0, 1, 0,-1, 0, 0, 0, 1, 0, 1]
    >>> dup_zz_cyclotomic_p(f, ZZ)
    False

    >>> g = [1, 0, 1, 0, 0, 0,-1, 0,-1, 0,-1, 0, 0, 0, 1, 0, 1]
    >>> dup_zz_cyclotomic_p(g, ZZ)
    True

    """
    if K.is_QQ:
        try:
            K0, K = K, K.get_ring()
            f = dup_convert(f, K0, K)
        except CoercionFailed:
            return False
    elif not K.is_ZZ:
        return False

    lc = dup_LC(f, K)
    tc = dup_TC(f, K)

    if lc != 1 or (tc != -1 and tc != 1):
        return False

    if not irreducible:
        coeff, factors = dup_factor_list(f, K)

        if coeff != K.one or factors != [(f, 1)]:
            return False

    n = dup_degree(f)
    g, h = [], []

    for i in xrange(n, -1, -2):
        g.insert(0, f[i])

    for i in xrange(n-1, -1, -2):
        h.insert(0, f[i])

    g = dup_sqr(dup_strip(g), K)
    h = dup_sqr(dup_strip(h), K)

    F = dup_sub(g, dup_lshift(h, 1, K), K)

    if K.is_negative(dup_LC(F, K)):
        F = dup_neg(F, K)

    if F == f:
        return True

    g = dup_mirror(f, K)

    if K.is_negative(dup_LC(g, K)):
        g = dup_neg(g, K)

    if F == g and dup_zz_cyclotomic_p(g, K):
        return True

    G = dup_sqf_part(F, K)

    if dup_sqr(G, K) == F and dup_zz_cyclotomic_p(G, K):
        return True

    return False

 def neg(f):
     return f.per(dup_neg(f.rep, f.dom))

def dup_zz_factor(f, K):
    """
    Factor (non square-free) polynomials in `Z[x]`.

    Given a univariate polynomial `f` in `Z[x]` computes its complete
    factorization `f_1, ..., f_n` into irreducibles over integers::

                f = content(f) f_1**k_1 ... f_n**k_n

    The factorization is computed by reducing the input polynomial
    into a primitive square-free polynomial and factoring it using
    Zassenhaus algorithm. Trial division is used to recover the
    multiplicities of factors.

    The result is returned as a tuple consisting of::

              (content(f), [(f_1, k_1), ..., (f_n, k_n))

    Consider polynomial `f = 2*x**4 - 2`::

        >>> from sympy.polys import ring, ZZ
        >>> R, x = ring("x", ZZ)

        >>> R.dup_zz_factor(2*x**4 - 2)
        (2, [(x - 1, 1), (x + 1, 1), (x**2 + 1, 1)])

    In result we got the following factorization::

                 f = 2 (x - 1) (x + 1) (x**2 + 1)

    Note that this is a complete factorization over integers,
    however over Gaussian integers we can factor the last term.

    By default, polynomials `x**n - 1` and `x**n + 1` are factored
    using cyclotomic decomposition to speedup computations. To
    disable this behaviour set cyclotomic=False.

    References
    ==========

    1. [Gathen99]_

    """
    cont, g = dup_primitive(f, K)

    n = dup_degree(g)

    if dup_LC(g, K) < 0:
        cont, g = -cont, dup_neg(g, K)

    if n <= 0:
        return cont, []
    elif n == 1:
        return cont, [(g, 1)]

    if query('USE_IRREDUCIBLE_IN_FACTOR'):
        if dup_zz_irreducible_p(g, K):
            return cont, [(g, 1)]

    g = dup_sqf_part(g, K)
    H = None

    if query('USE_CYCLOTOMIC_FACTOR'):
        H = dup_zz_cyclotomic_factor(g, K)

    if H is None:
        H = dup_zz_zassenhaus(g, K)

    factors = dup_trial_division(f, H, K)
    return cont, factors