import decimal
import random
from decimal import Decimal
from fractions import Fraction

import pytest

from mpmath import iv, mp, mpc, mpf, mpi, mpmathify, sqrt
from mpmath.libmp import (fhalf, from_float, from_rational, from_str,
                          round_ceiling, round_floor, round_nearest,
                          to_rational, to_str)


def test_basic_string():
    """
    Test basic string conversion
    """
    assert mpf('3') == mpf('3.0') == mpf('0003.') == mpf('0.03e2') == mpf(3.0)
    assert mpf('30') == mpf('30.0') == mpf('00030.') == mpf(30.0)
    for i in range(10):
        for j in range(10):
            assert mpf('%ie%i' % (i,j)) == i * 10**j
    assert str(mpf('25000.0')) == '25000.0'
    assert str(mpf('2500.0')) == '2500.0'
    assert str(mpf('250.0')) == '250.0'
    assert str(mpf('25.0')) == '25.0'
    assert str(mpf('2.5')) == '2.5'
    assert str(mpf('0.25')) == '0.25'
    assert str(mpf('0.025')) == '0.025'
    assert str(mpf('0.0025')) == '0.0025'
    assert str(mpf('0.00025')) == '0.00025'
    assert str(mpf('0.000025')) == '2.5e-5'
    assert str(mpf(0)) == '0.0'
    assert str(mpf('2.5e1000000000000000000000')) == '2.5e+1000000000000000000000'
    assert str(mpf('2.6e-1000000000000000000000')) == '2.6e-1000000000000000000000'
    assert str(mpf(1.23402834e-15)) == '1.23402834e-15'
    assert str(mpf(-1.23402834e-15)) == '-1.23402834e-15'
    assert str(mpf(-1.2344e-15)) == '-1.2344e-15'
    assert repr(mpf(-1.2344e-15)) == "mpf('-1.2343999999999999e-15')"
    assert str(mpf("2163048125L")) == '2163048125.0'
    assert str(mpf("-2163048125l")) == '-2163048125.0'
    assert str(mpf("-2163048125L/1088391168")) == '-1.98738118113799'
    assert str(mpf("2163048125/1088391168l")) == '1.98738118113799'
    assert str(mpf('inf')) == '+inf'

    # issue 613
    assert str(mpf('2_5_0_0.0')) == '2500.0'
    # issue 377
    assert to_str(from_str('1_234.567891', 80), 24) == '1234.567891'
    assert to_str(from_str('1_234.567_891', 80), 24) == '1234.567891'
    assert to_str(from_str('1_234.567_8_9_1', 80), 24) == '1234.567891'
    assert to_str(from_str('1.0_0', 80), 24) == '1.0'
    assert to_str(from_str('.000', 80), 24) == '0.0'

def test_from_str():
    assert mpf(from_str('ABC.ABC', base=16)) == mpf(float.fromhex('ABC.ABC'))
    assert mpf(from_str('0xABC.ABC')) == mpf(float.fromhex('ABC.ABC'))
    assert mpf(from_str('0x3.a7p10')) == mpf(float.fromhex('0x3.a7p10'))
    assert mpf(from_str('0x1.4ace478p+33')) == mpf(float.fromhex('0x1.4ace478p+33'))
    assert mpf(from_str('0x1.4ace478@+33')) == mpf('7.0354608312666732e+39')
    assert mpf(from_str('0b1101.100101')) == mpf('13.578125')
    assert mpf(from_str('0o1101.100101')) == mpf('577.12524795532227')

def test_eps_repr():
    mp.dps = 24
    assert repr(mp.eps) == '<epsilon of working precision: 2.06795e-25~>'

def test_pretty():
    mp.pretty = True
    assert repr(mpf(2.5)) == '2.5'
    assert repr(mpc(2.5,3.5)) == '(2.5 + 3.5j)'
    iv.pretty = True
    assert repr(mpi(2.5,3.5)) == '[2.5, 3.5]'

def test_str_whitespace():
    assert mpf('1.26 ') == 1.26

def test_str_format():
    assert to_str(from_float(0.1),15,strip_zeros=False) == '0.100000000000000'
    assert to_str(from_float(0.0),15,show_zero_exponent=True) == '0.0e+0'
    assert to_str(from_float(0.0),0,show_zero_exponent=True) == '.0e+0'
    assert to_str(from_float(0.0),0,show_zero_exponent=False) == '.0'
    assert to_str(from_float(0.0),1,show_zero_exponent=True) == '0.0e+0'
    assert to_str(from_float(0.0),1,show_zero_exponent=False) == '0.0'
    assert to_str(from_float(1.23),3,show_zero_exponent=True) == '1.23e+0'
    assert to_str(from_float(1.23456789000000e-2),15,strip_zeros=False,min_fixed=0,max_fixed=0) == '1.23456789000000e-2'
    assert to_str(from_float(1.23456789000000e+2),15,strip_zeros=False,min_fixed=0,max_fixed=0) == '1.23456789000000e+2'
    assert to_str(from_float(2.1287e14), 15, max_fixed=1000) == '212870000000000.0'
    assert to_str(from_float(2.1287e15), 15, max_fixed=1000) == '2128700000000000.0'
    assert to_str(from_float(2.1287e16), 15, max_fixed=1000) == '21287000000000000.0'
    assert to_str(from_float(2.1287e30), 15, max_fixed=1000) == '2128700000000000000000000000000.0'

def test_tight_string_conversion():
    # In an old version, '0.5' wasn't recognized as representing
    # an exact binary number and was erroneously rounded up or down
    assert from_str('0.5', 10, round_floor) == fhalf
    assert from_str('0.5', 10, round_ceiling) == fhalf

def test_eval_repr_invariant():
    """Test that eval(repr(x)) == x"""
    random.seed(123)
    for dps in [10, 15, 20, 50, 100]:
        mp.dps = dps
        for i in range(1000):
            a = mpf(random.random())**0.5 * 10**random.randint(-100, 100)
            assert eval(repr(a)) == a

def test_str_bugs():
    # Decimal rounding used to give the wrong exponent in some cases
    assert str(mpf('1e600')) == '1.0e+600'
    assert str(mpf('1e10000')) == '1.0e+10000'

def test_str_prec0():
    assert to_str(from_float(1.234), 0) == '.0e+0'
    assert to_str(from_float(1e-15), 0) == '.0e-15'
    assert to_str(from_float(1e+15), 0) == '.0e+15'
    assert to_str(from_float(-1e-15), 0) == '-.0e-15'
    assert to_str(from_float(-1e+15), 0) == '-.0e+15'

def test_convert_rational():
    assert from_rational(30, 5, 53, round_nearest) == (0, 3, 1, 2)
    assert from_rational(-7, 4, 53, round_nearest) == (1, 7, -2, 3)
    assert to_rational((0, 1, -1, 1)) == (1, 2)
    assert to_rational((0, 1, 0, 1)) == (1, 1)
    pytest.raises(ValueError, lambda: to_rational(mpf('nan')._mpf_))
    pytest.raises(OverflowError, lambda: to_rational(mpf('inf')._mpf_))
    pytest.raises(OverflowError, lambda: to_rational(mpf('-inf')._mpf_))

def test_custom_class():
    class mympf:
        @property
        def _mpf_(self):
            return mpf(3.5)._mpf_
    class mympc:
        @property
        def _mpc_(self):
            return mpf(3.5)._mpf_, mpf(2.5)._mpf_
    assert mpf(2) + mympf() == 5.5
    assert mympf() + mpf(2) == 5.5
    assert mpf(mympf()) == 3.5
    assert mympc() + mpc(2) == mpc(5.5, 2.5)
    assert mpc(2) + mympc() == mpc(5.5, 2.5)
    assert mpc(mympc()) == (3.5+2.5j)
    assert mpmathify(mympf()) == mpf(3.5)
    assert mpmathify(mympc()) == mpc(3.5, 2.5)

def test_conversion_methods():
    class SomethingRandom:
        pass
    class SomethingReal:
        def _mpmath_(self, prec, rounding):
            return mp.make_mpf(from_str('1.3', prec, rounding))
    class SomethingComplex:
        def _mpmath_(self, prec, rounding):
            return mp.make_mpc((from_str('1.3', prec, rounding), \
                from_str('1.7', prec, rounding)))
    x = mpf(3)
    z = mpc(3)
    a = SomethingRandom()
    y = SomethingReal()
    w = SomethingComplex()
    for d in [15, 45]:
        mp.dps = d
        assert (x+y).ae(mpf('4.3'))
        assert (y+x).ae(mpf('4.3'))
        assert (x+w).ae(mpc('4.3', '1.7'))
        assert (w+x).ae(mpc('4.3', '1.7'))
        assert (z+y).ae(mpc('4.3'))
        assert (y+z).ae(mpc('4.3'))
        assert (z+w).ae(mpc('4.3', '1.7'))
        assert (w+z).ae(mpc('4.3', '1.7'))
        x-y; y-x; x-w; w-x; z-y; y-z; z-w; w-z
        x*y; y*x; x*w; w*x; z*y; y*z; z*w; w*z
        x/y; y/x; x/w; w/x; z/y; y/z; z/w; w/z
        x**y; y**x; x**w; w**x; z**y; y**z; z**w; w**z
        x==y; y==x; x==w; w==x; z==y; y==z; z==w; w==z
    mp.dps = 15
    assert x.__add__(a) is NotImplemented
    assert x.__radd__(a) is NotImplemented
    assert x.__lt__(a) is NotImplemented
    assert x.__gt__(a) is NotImplemented
    assert x.__le__(a) is NotImplemented
    assert x.__ge__(a) is NotImplemented
    assert x.__eq__(a) is NotImplemented
    assert x.__ne__(a) is NotImplemented
    assert x.__sub__(a) is NotImplemented
    assert x.__rsub__(a) is NotImplemented
    assert x.__mul__(a) is NotImplemented
    assert x.__rmul__(a) is NotImplemented
    assert x.__truediv__(a) is NotImplemented
    assert x.__rtruediv__(a) is NotImplemented
    assert x.__mod__(a) is NotImplemented
    assert x.__rmod__(a) is NotImplemented
    assert x.__pow__(a) is NotImplemented
    assert x.__rpow__(a) is NotImplemented
    assert z.__add__(a) is NotImplemented
    assert z.__radd__(a) is NotImplemented
    assert z.__eq__(a) is NotImplemented
    assert z.__ne__(a) is NotImplemented
    assert z.__sub__(a) is NotImplemented
    assert z.__rsub__(a) is NotImplemented
    assert z.__mul__(a) is NotImplemented
    assert z.__rmul__(a) is NotImplemented
    assert z.__truediv__(a) is NotImplemented
    assert z.__rtruediv__(a) is NotImplemented
    assert z.__pow__(a) is NotImplemented
    assert z.__rpow__(a) is NotImplemented

def test_mpmathify():
    assert mpmathify('1/2') == 0.5
    assert mpmathify('(1.0+1.0j)') == mpc(1, 1)
    assert mpmathify('(1.2e-10 - 3.4e5j)') == mpc('1.2e-10', '-3.4e5')
    assert mpmathify('1j') == mpc(1j)

def test_issue548():
    try:
        # This expression is invalid, but may trigger the ReDOS vulnerability
        # in the regular expression for parsing complex numbers.
        mpmathify('(' + '1' * 5000 + '!j')
    except:
        return
    # The expression is invalid and should raise an exception.
    assert False

def test_compatibility():
    np = pytest.importorskip("numpy")
    # numpy types
    for nptype in np.core.numerictypes.typeDict.values():
        if issubclass(nptype, np.complexfloating):
            x = nptype(complex(0.5, -0.5))
        elif issubclass(nptype, np.floating):
            x = nptype(0.5)
        elif issubclass(nptype, np.integer):
            x = nptype(2)
        # Handle the weird types
        try: diff = np.abs(type(np.sqrt(x))(sqrt(x)) - np.sqrt(x))
        except: continue
        assert diff < 2.0**-53
    # issues 382 and 539
    assert mp.sqrt(np.int64(1)) == mpf('1.0')
    assert mpf(np.int64(1)) == mpf('1.0')
    #Fraction and Decimal
    oldprec = mp.prec
    mp.prec = 1000
    decimal.getcontext().prec = mp.dps
    assert sqrt(Fraction(2, 3)).ae(sqrt(mpf('2/3')))
    assert sqrt(Decimal(2)/Decimal(3)).ae(sqrt(mpf('2/3')))
    mp.prec = oldprec
    pytest.raises(TypeError, lambda: mpmathify(np.array(1)))

def test_issue465():
    assert mpf(Fraction(1, 3)) == mpf('0.33333333333333331')
