# Tests that require installed backends go into
# sympy/test_external/test_autowrap

import os
import tempfile
import shutil
import warnings
import tempfile

from sympy.core import symbols, Eq
from sympy.core.compatibility import StringIO
from sympy.utilities.exceptions import SymPyDeprecationWarning
from sympy.utilities.pytest import raises
from sympy.utilities.autowrap import (autowrap, binary_function,
            CythonCodeWrapper, ufuncify, UfuncifyCodeWrapper, CodeWrapper)
from sympy.utilities.codegen import (
    CCodeGen, C99CodeGen, CodeGenArgumentListError, make_routine
)


def get_string(dump_fn, routines, prefix="file", **kwargs):
    """Wrapper for dump_fn. dump_fn writes its results to a stream object and
       this wrapper returns the contents of that stream as a string. This
       auxiliary function is used by many tests below.

       The header and the empty lines are not generator to facilitate the
       testing of the output.
    """
    output = StringIO()
    dump_fn(routines, output, prefix, **kwargs)
    source = output.getvalue()
    output.close()
    return source


def test_cython_wrapper_scalar_function():
    x, y, z = symbols('x,y,z')
    expr = (x + y)*z
    routine = make_routine("test", expr)
    with warnings.catch_warnings():
        warnings.filterwarnings('ignore', category=SymPyDeprecationWarning)
        code_gen = CythonCodeWrapper(CCodeGen())
        source = get_string(code_gen.dump_pyx, [routine])

    expected = (
        "cdef extern from 'file.h':\n"
        "    double test(double x, double y, double z)\n"
        "\n"
        "def test_c(double x, double y, double z):\n"
        "\n"
        "    return test(x, y, z)")
    assert source == expected


def test_cython_wrapper_outarg():
    from sympy import Equality
    x, y, z = symbols('x,y,z')
    code_gen = CythonCodeWrapper(C99CodeGen())

    routine = make_routine("test", Equality(z, x + y))
    source = get_string(code_gen.dump_pyx, [routine])
    expected = (
        "cdef extern from 'file.h':\n"
        "    void test(double x, double y, double *z)\n"
        "\n"
        "def test_c(double x, double y):\n"
        "\n"
        "    cdef double z = 0\n"
        "    test(x, y, &z)\n"
        "    return z")
    assert source == expected


def test_cython_wrapper_inoutarg():
    from sympy import Equality
    x, y, z = symbols('x,y,z')
    code_gen = CythonCodeWrapper(C99CodeGen())
    routine = make_routine("test", Equality(z, x + y + z))
    source = get_string(code_gen.dump_pyx, [routine])
    expected = (
        "cdef extern from 'file.h':\n"
        "    void test(double x, double y, double *z)\n"
        "\n"
        "def test_c(double x, double y, double z):\n"
        "\n"
        "    test(x, y, &z)\n"
        "    return z")
    assert source == expected


def test_cython_wrapper_compile_flags():
    from sympy import Equality
    x, y, z = symbols('x,y,z')
    routine = make_routine("test", Equality(z, x + y))

    code_gen = CythonCodeWrapper(CCodeGen())

    expected = """\
try:
    from setuptools import setup
    from setuptools import Extension
except ImportError:
    from distutils.core import setup
    from distutils.extension import Extension
from Cython.Build import cythonize
cy_opts = {}

ext_mods = [Extension(
    'wrapper_module_%(num)s', ['wrapper_module_%(num)s.pyx', 'wrapped_code_%(num)s.c'],
    include_dirs=[],
    library_dirs=[],
    libraries=[],
    extra_compile_args=['-std=c99'],
    extra_link_args=[]
)]
setup(ext_modules=cythonize(ext_mods, **cy_opts))
""" % {'num': CodeWrapper._module_counter}

    temp_dir = tempfile.mkdtemp()
    setup_file_path = os.path.join(temp_dir, 'setup.py')

    code_gen._prepare_files(routine, build_dir=temp_dir)
    with open(setup_file_path) as f:
        setup_text = f.read()
    assert setup_text == expected

    code_gen = CythonCodeWrapper(CCodeGen(),
                                 include_dirs=['/usr/local/include', '/opt/booger/include'],
                                 library_dirs=['/user/local/lib'],
                                 libraries=['thelib', 'nilib'],
                                 extra_compile_args=['-slow-math'],
                                 extra_link_args=['-lswamp', '-ltrident'],
                                 cythonize_options={'compiler_directives': {'boundscheck': False}}
                                 )
    expected = """\
try:
    from setuptools import setup
    from setuptools import Extension
except ImportError:
    from distutils.core import setup
    from distutils.extension import Extension
from Cython.Build import cythonize
cy_opts = {'compiler_directives': {'boundscheck': False}}

ext_mods = [Extension(
    'wrapper_module_%(num)s', ['wrapper_module_%(num)s.pyx', 'wrapped_code_%(num)s.c'],
    include_dirs=['/usr/local/include', '/opt/booger/include'],
    library_dirs=['/user/local/lib'],
    libraries=['thelib', 'nilib'],
    extra_compile_args=['-slow-math', '-std=c99'],
    extra_link_args=['-lswamp', '-ltrident']
)]
setup(ext_modules=cythonize(ext_mods, **cy_opts))
""" % {'num': CodeWrapper._module_counter}

    code_gen._prepare_files(routine, build_dir=temp_dir)
    with open(setup_file_path) as f:
        setup_text = f.read()
    assert setup_text == expected

    expected = """\
try:
    from setuptools import setup
    from setuptools import Extension
except ImportError:
    from distutils.core import setup
    from distutils.extension import Extension
from Cython.Build import cythonize
cy_opts = {'compiler_directives': {'boundscheck': False}}
import numpy as np

ext_mods = [Extension(
    'wrapper_module_%(num)s', ['wrapper_module_%(num)s.pyx', 'wrapped_code_%(num)s.c'],
    include_dirs=['/usr/local/include', '/opt/booger/include', np.get_include()],
    library_dirs=['/user/local/lib'],
    libraries=['thelib', 'nilib'],
    extra_compile_args=['-slow-math', '-std=c99'],
    extra_link_args=['-lswamp', '-ltrident']
)]
setup(ext_modules=cythonize(ext_mods, **cy_opts))
""" % {'num': CodeWrapper._module_counter}

    code_gen._need_numpy = True
    code_gen._prepare_files(routine, build_dir=temp_dir)
    with open(setup_file_path) as f:
        setup_text = f.read()
    assert setup_text == expected

def test_autowrap_dummy():
    x, y, z = symbols('x y z')

    # Uses DummyWrapper to test that codegen works as expected

    f = autowrap(x + y, backend='dummy')
    assert f() == str(x + y)
    assert f.args == "x, y"
    assert f.returns == "nameless"
    f = autowrap(Eq(z, x + y), backend='dummy')
    assert f() == str(x + y)
    assert f.args == "x, y"
    assert f.returns == "z"
    f = autowrap(Eq(z, x + y + z), backend='dummy')
    assert f() == str(x + y + z)
    assert f.args == "x, y, z"
    assert f.returns == "z"


def test_autowrap_args():
    x, y, z = symbols('x y z')

    raises(CodeGenArgumentListError, lambda: autowrap(Eq(z, x + y),
           backend='dummy', args=[x]))
    f = autowrap(Eq(z, x + y), backend='dummy', args=[y, x])
    assert f() == str(x + y)
    assert f.args == "y, x"
    assert f.returns == "z"

    raises(CodeGenArgumentListError, lambda: autowrap(Eq(z, x + y + z),
           backend='dummy', args=[x, y]))
    f = autowrap(Eq(z, x + y + z), backend='dummy', args=[y, x, z])
    assert f() == str(x + y + z)
    assert f.args == "y, x, z"
    assert f.returns == "z"

    f = autowrap(Eq(z, x + y + z), backend='dummy', args=(y, x, z))
    assert f() == str(x + y + z)
    assert f.args == "y, x, z"
    assert f.returns == "z"


def test_autowrap_store_files():
    x, y = symbols('x y')
    tmp = tempfile.mkdtemp()
    try:
        f = autowrap(x + y, backend='dummy', tempdir=tmp)
        assert f() == str(x + y)
        assert os.access(tmp, os.F_OK)
    finally:
        shutil.rmtree(tmp)


def test_binary_function():
    x, y = symbols('x y')
    f = binary_function('f', x + y, backend='dummy')
    assert f._imp_() == str(x + y)


def test_ufuncify_source():
    x, y, z = symbols('x,y,z')
    code_wrapper = UfuncifyCodeWrapper(C99CodeGen("ufuncify"))
    CodeWrapper._module_counter = 0
    routine = make_routine("test", x + y + z)
    source = get_string(code_wrapper.dump_c, [routine])
    expected = """\
#include "Python.h"
#include "math.h"
#include "numpy/ndarraytypes.h"
#include "numpy/ufuncobject.h"
#include "numpy/halffloat.h"
#include "file.h"

static PyMethodDef wrapper_module_0Methods[] = {
        {NULL, NULL, 0, NULL}
};

static void test_ufunc(char **args, npy_intp *dimensions, npy_intp* steps, void* data)
{
    npy_intp i;
    npy_intp n = dimensions[0];
    char *in0 = args[0];
    char *in1 = args[1];
    char *in2 = args[2];
    char *out0 = args[3];
    npy_intp in0_step = steps[0];
    npy_intp in1_step = steps[1];
    npy_intp in2_step = steps[2];
    npy_intp out0_step = steps[3];
    for (i = 0; i < n; i++) {
        *((double *)out0) = test(*(double *)in0, *(double *)in1, *(double *)in2);
        in0 += in0_step;
        in1 += in1_step;
        in2 += in2_step;
        out0 += out0_step;
    }
}
PyUFuncGenericFunction test_funcs[1] = {&test_ufunc};
static char test_types[4] = {NPY_DOUBLE, NPY_DOUBLE, NPY_DOUBLE, NPY_DOUBLE};
static void *test_data[1] = {NULL};

#if PY_VERSION_HEX >= 0x03000000
static struct PyModuleDef moduledef = {
    PyModuleDef_HEAD_INIT,
    "wrapper_module_0",
    NULL,
    -1,
    wrapper_module_0Methods,
    NULL,
    NULL,
    NULL,
    NULL
};

PyMODINIT_FUNC PyInit_wrapper_module_0(void)
{
    PyObject *m, *d;
    PyObject *ufunc0;
    m = PyModule_Create(&moduledef);
    if (!m) {
        return NULL;
    }
    import_array();
    import_umath();
    d = PyModule_GetDict(m);
    ufunc0 = PyUFunc_FromFuncAndData(test_funcs, test_data, test_types, 1, 3, 1,
            PyUFunc_None, "wrapper_module_0", "Created in SymPy with Ufuncify", 0);
    PyDict_SetItemString(d, "test", ufunc0);
    Py_DECREF(ufunc0);
    return m;
}
#else
PyMODINIT_FUNC initwrapper_module_0(void)
{
    PyObject *m, *d;
    PyObject *ufunc0;
    m = Py_InitModule("wrapper_module_0", wrapper_module_0Methods);
    if (m == NULL) {
        return;
    }
    import_array();
    import_umath();
    d = PyModule_GetDict(m);
    ufunc0 = PyUFunc_FromFuncAndData(test_funcs, test_data, test_types, 1, 3, 1,
            PyUFunc_None, "wrapper_module_0", "Created in SymPy with Ufuncify", 0);
    PyDict_SetItemString(d, "test", ufunc0);
    Py_DECREF(ufunc0);
}
#endif"""
    assert source == expected


def test_ufuncify_source_multioutput():
    x, y, z = symbols('x,y,z')
    var_symbols = (x, y, z)
    expr = x + y**3 + 10*z**2
    code_wrapper = UfuncifyCodeWrapper(C99CodeGen("ufuncify"))
    CodeWrapper._module_counter = 0
    routines = [make_routine("func{}".format(i), expr.diff(var_symbols[i]), var_symbols) for i in range(len(var_symbols))]
    source = get_string(code_wrapper.dump_c, routines, funcname='multitest')
    expected = """\
#include "Python.h"
#include "math.h"
#include "numpy/ndarraytypes.h"
#include "numpy/ufuncobject.h"
#include "numpy/halffloat.h"
#include "file.h"

static PyMethodDef wrapper_module_0Methods[] = {
        {NULL, NULL, 0, NULL}
};

static void multitest_ufunc(char **args, npy_intp *dimensions, npy_intp* steps, void* data)
{
    npy_intp i;
    npy_intp n = dimensions[0];
    char *in0 = args[0];
    char *in1 = args[1];
    char *in2 = args[2];
    char *out0 = args[3];
    char *out1 = args[4];
    char *out2 = args[5];
    npy_intp in0_step = steps[0];
    npy_intp in1_step = steps[1];
    npy_intp in2_step = steps[2];
    npy_intp out0_step = steps[3];
    npy_intp out1_step = steps[4];
    npy_intp out2_step = steps[5];
    for (i = 0; i < n; i++) {
        *((double *)out0) = func0(*(double *)in0, *(double *)in1, *(double *)in2);
        *((double *)out1) = func1(*(double *)in0, *(double *)in1, *(double *)in2);
        *((double *)out2) = func2(*(double *)in0, *(double *)in1, *(double *)in2);
        in0 += in0_step;
        in1 += in1_step;
        in2 += in2_step;
        out0 += out0_step;
        out1 += out1_step;
        out2 += out2_step;
    }
}
PyUFuncGenericFunction multitest_funcs[1] = {&multitest_ufunc};
static char multitest_types[6] = {NPY_DOUBLE, NPY_DOUBLE, NPY_DOUBLE, NPY_DOUBLE, NPY_DOUBLE, NPY_DOUBLE};
static void *multitest_data[1] = {NULL};

#if PY_VERSION_HEX >= 0x03000000
static struct PyModuleDef moduledef = {
    PyModuleDef_HEAD_INIT,
    "wrapper_module_0",
    NULL,
    -1,
    wrapper_module_0Methods,
    NULL,
    NULL,
    NULL,
    NULL
};

PyMODINIT_FUNC PyInit_wrapper_module_0(void)
{
    PyObject *m, *d;
    PyObject *ufunc0;
    m = PyModule_Create(&moduledef);
    if (!m) {
        return NULL;
    }
    import_array();
    import_umath();
    d = PyModule_GetDict(m);
    ufunc0 = PyUFunc_FromFuncAndData(multitest_funcs, multitest_data, multitest_types, 1, 3, 3,
            PyUFunc_None, "wrapper_module_0", "Created in SymPy with Ufuncify", 0);
    PyDict_SetItemString(d, "multitest", ufunc0);
    Py_DECREF(ufunc0);
    return m;
}
#else
PyMODINIT_FUNC initwrapper_module_0(void)
{
    PyObject *m, *d;
    PyObject *ufunc0;
    m = Py_InitModule("wrapper_module_0", wrapper_module_0Methods);
    if (m == NULL) {
        return;
    }
    import_array();
    import_umath();
    d = PyModule_GetDict(m);
    ufunc0 = PyUFunc_FromFuncAndData(multitest_funcs, multitest_data, multitest_types, 1, 3, 3,
            PyUFunc_None, "wrapper_module_0", "Created in SymPy with Ufuncify", 0);
    PyDict_SetItemString(d, "multitest", ufunc0);
    Py_DECREF(ufunc0);
}
#endif"""
    assert source == expected
