import pytest

from diofant import (Derivative, Eq, Function, Ge, Gt, Integral, Le, Lt,
                     Matrix, Ne, Rational, Symbol, cbrt, exp, limit, log, oo,
                     pi, root, sin, sqrt)
from diofant.abc import x, y
from diofant.printing.python import python


__all__ = ()


def test_python_basic():
    # Simple numbers/symbols
    assert python(-Rational(1, 2)) == "e = Rational(-1, 2)"
    assert python(-Rational(13, 22)) == "e = Rational(-13, 22)"
    assert python(oo) == "e = oo"

    # Powers
    assert python((x**2)) == "x = Symbol(\'x\')\ne = x**2"
    assert python(1/x) == "x = Symbol('x')\ne = 1/x"
    assert python(y*x**-2) == "y = Symbol('y')\nx = Symbol('x')\ne = y/x**2"
    assert python(
        x**Rational(-5, 2)) == "x = Symbol('x')\ne = x**Rational(-5, 2)"

    # Sums of terms
    assert python((x**2 + x + 1)) in [
        "x = Symbol('x')\ne = 1 + x + x**2",
        "x = Symbol('x')\ne = x + x**2 + 1",
        "x = Symbol('x')\ne = x**2 + x + 1", ]
    assert python(1 - x) in [
        "x = Symbol('x')\ne = 1 - x",
        "x = Symbol('x')\ne = -x + 1"]
    assert python(1 - 2*x) in [
        "x = Symbol('x')\ne = 1 - 2*x",
        "x = Symbol('x')\ne = -2*x + 1"]
    assert python(1 - Rational(3, 2)*y/x) in [
        "y = Symbol('y')\nx = Symbol('x')\ne = 1 - 3/2*y/x",
        "y = Symbol('y')\nx = Symbol('x')\ne = -3/2*y/x + 1",
        "y = Symbol('y')\nx = Symbol('x')\ne = 1 - 3*y/(2*x)"]

    # Multiplication
    assert python(x/y) == "x = Symbol('x')\ny = Symbol('y')\ne = x/y"
    assert python(-x/y) == "x = Symbol('x')\ny = Symbol('y')\ne = -x/y"
    assert python((x + 2)/y) in [
        "y = Symbol('y')\nx = Symbol('x')\ne = 1/y*(2 + x)",
        "y = Symbol('y')\nx = Symbol('x')\ne = 1/y*(x + 2)",
        "x = Symbol('x')\ny = Symbol('y')\ne = 1/y*(2 + x)",
        "x = Symbol('x')\ny = Symbol('y')\ne = (2 + x)/y",
        "x = Symbol('x')\ny = Symbol('y')\ne = (x + 2)/y"]
    assert python((1 + x)*y) in [
        "y = Symbol('y')\nx = Symbol('x')\ne = y*(1 + x)",
        "y = Symbol('y')\nx = Symbol('x')\ne = y*(x + 1)", ]

    # Check for proper placement of negative sign
    assert python(-5*x/(x + 10)) == "x = Symbol('x')\ne = -5*x/(x + 10)"
    assert python(1 - Rational(3, 2)*(x + 1)) in [
        "x = Symbol('x')\ne = Rational(-3, 2)*x + Rational(-1, 2)",
        "x = Symbol('x')\ne = -3*x/2 + Rational(-1, 2)",
        "x = Symbol('x')\ne = -3*x/2 + Rational(-1, 2)"
    ]


def test_python_keyword_symbol_name_escaping():
    # Check for escaping of keywords
    assert python(
        5*Symbol("lambda")) == "lambda_ = Symbol('lambda')\ne = 5*lambda_"
    assert (python(5*Symbol("lambda") + 7*Symbol("lambda_")) ==
            "lambda__ = Symbol('lambda')\nlambda_ = Symbol('lambda_')\ne = 7*lambda_ + 5*lambda__")
    assert (python(5*Symbol("for") + Function("for_")(8)) ==
            "for__ = Symbol('for')\nfor_ = Function('for_')\ne = 5*for__ + for_(8)")
    assert (python(5*Symbol("for_") + Function("for")(8)) ==
            "for_ = Symbol('for_')\nfor__ = Function('for')\ne = 5*for_ + for__(8)")


def test_python_keyword_function_name_escaping():
    assert python(
        5*Function("for")(8)) == "for_ = Function('for')\ne = 5*for_(8)"


def test_python_relational():
    assert python(Eq(x, y)) == "e = Eq(x, y)"
    assert python(Ge(x, y)) == "x = Symbol('x')\ny = Symbol('y')\ne = x >= y"
    assert python(Le(x, y)) == "x = Symbol('x')\ny = Symbol('y')\ne = x <= y"
    assert python(Gt(x, y)) == "x = Symbol('x')\ny = Symbol('y')\ne = x > y"
    assert python(Lt(x, y)) == "x = Symbol('x')\ny = Symbol('y')\ne = x < y"
    assert python(Ne(x/(y + 1), y**2)) in ["e = Ne(x/(1 + y), y**2)", "e = Ne(x/(y + 1), y**2)"]


def test_python_functions():
    # Simple
    assert python((2*x + exp(x))) in "x = Symbol('x')\ne = E**x + 2*x"
    assert python(sqrt(2)) == 'e = sqrt(2)'
    assert python(cbrt(2)) == 'e = 2**Rational(1, 3)'
    assert python(sqrt(2 + pi)) == 'e = sqrt(2 + pi)'
    assert python(cbrt(2 + pi)) == 'e = (2 + pi)**Rational(1, 3)'
    assert python(root(2, 4)) == 'e = 2**Rational(1, 4)'
    assert python(abs(x)) == "x = Symbol('x')\ne = Abs(x)"
    assert python(
        abs(x/(x**2 + 1))) in ["x = Symbol('x')\ne = Abs(x/(1 + x**2))",
                               "x = Symbol('x')\ne = Abs(x/(x**2 + 1))"]

    # Univariate/Multivariate functions
    f = Function('f')
    assert python(f(x)) == "x = Symbol('x')\nf = Function('f')\ne = f(x)"
    assert python(f(x, y)) == "x = Symbol('x')\ny = Symbol('y')\nf = Function('f')\ne = f(x, y)"
    assert python(f(x/(y + 1), y)) in [
        "x = Symbol('x')\ny = Symbol('y')\nf = Function('f')\ne = f(x/(1 + y), y)",
        "x = Symbol('x')\ny = Symbol('y')\nf = Function('f')\ne = f(x/(y + 1), y)"]

    # Nesting of square roots
    assert python(sqrt((sqrt(x + 1)) + 1)) in [
        "x = Symbol('x')\ne = sqrt(1 + sqrt(1 + x))",
        "x = Symbol('x')\ne = sqrt(sqrt(x + 1) + 1)"]

    # Nesting of powers
    assert python(cbrt(cbrt(x + 1) + 1)) in [
        "x = Symbol('x')\ne = (1 + (1 + x)**Rational(1, 3))**Rational(1, 3)",
        "x = Symbol('x')\ne = ((x + 1)**Rational(1, 3) + 1)**Rational(1, 3)"]

    # Function powers
    assert python(sin(x)**2) == "x = Symbol('x')\ne = sin(x)**2"


def test_python_derivatives():
    # Simple
    f_1 = Derivative(log(x), x, evaluate=False)
    assert python(f_1) == "x = Symbol('x')\ne = Derivative(log(x), x)"

    f_2 = Derivative(log(x), x, evaluate=False) + x
    assert python(f_2) == "x = Symbol('x')\ne = x + Derivative(log(x), x)"

    # Multiple symbols
    f_3 = Derivative(log(x) + x**2, x, y, evaluate=False)
    assert python(f_3) == \
        "x = Symbol('x')\ny = Symbol('y')\ne = Derivative(x**2 + log(x), x, y)"

    f_4 = Derivative(2*x*y, y, x, evaluate=False) + x**2
    assert python(f_4) in [
        "x = Symbol('x')\ny = Symbol('y')\ne = x**2 + Derivative(2*x*y, y, x)",
        "x = Symbol('x')\ny = Symbol('y')\ne = Derivative(2*x*y, y, x) + x**2"]


def test_python_integrals():
    # Simple
    f_1 = Integral(log(x), x)
    assert python(f_1) == "x = Symbol('x')\ne = Integral(log(x), x)"

    f_2 = Integral(x**2, x)
    assert python(f_2) == "x = Symbol('x')\ne = Integral(x**2, x)"

    # Double nesting of pow
    f_3 = Integral(x**(2**x), x)
    assert python(f_3) == "x = Symbol('x')\ne = Integral(x**(2**x), x)"

    # Definite integrals
    f_4 = Integral(x**2, (x, 1, 2))
    assert python(f_4) == "x = Symbol('x')\ne = Integral(x**2, (x, 1, 2))"

    f_5 = Integral(x**2, (x, Rational(1, 2), 10))
    assert python(
        f_5) == "x = Symbol('x')\ne = Integral(x**2, (x, Rational(1, 2), 10))"

    # Nested integrals
    f_6 = Integral(x**2*y**2, x, y)
    assert python(f_6) == "x = Symbol('x')\ny = Symbol('y')\ne = Integral(x**2*y**2, x, y)"


def test_python_matrix():
    p = python(Matrix([[x**2+1, 1], [y, x+y]]))
    s = "x = Symbol('x')\ny = Symbol('y')\ne = MutableDenseMatrix([[x**2 + 1, 1], [y, x + y]])"
    assert p == s


def test_python_limits():
    assert python(limit(x, x, oo)) == 'e = oo'
    assert python(limit(x**2, x, 0)) == 'e = 0'


def test_settings():
    pytest.raises(TypeError, lambda: python(x, method="garbage"))
