#!/usr/bin/env python

# Copyright (c) 2017-present, Facebook, Inc.
# All rights reserved.
#
# This source code is licensed under the BSD-style license found in the
# LICENSE file in the root directory of this source tree. An additional grant
# of patent rights can be found in the PATENTS file in the same directory.

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
from __future__ import unicode_literals

from setuptools import setup, Extension
from setuptools.command.build_ext import build_ext
import sys
import setuptools
import os

__version__ = '0.0.2'
FASTTEXT_SRC = "src"

# Based on https://github.com/pybind/python_example

class get_pybind_include(object):
    """Helper class to determine the pybind11 include path
    The purpose of this class is to postpone importing pybind11
    until it is actually installed, so that the ``get_include()``
    method can be invoked. """

    def __init__(self, user=False):
        self.user = user

    def __str__(self):
        import pybind11
        return pybind11.get_include(self.user)


fasttext_src_files = map(str, os.listdir(FASTTEXT_SRC))
fasttext_src_cc = list(filter(lambda x: x.endswith('.cc'), fasttext_src_files))

fasttext_src_cc = list(
    map(lambda x: str(os.path.join(FASTTEXT_SRC, x)), fasttext_src_cc)
)

ext_modules = [
    Extension(
        str('fasttext_pybind'),
        [
            str('python/fastText/pybind/fasttext_pybind.cc'),
        ] + fasttext_src_cc,
        include_dirs=[
            # Path to pybind11 headers
            get_pybind_include(),
            get_pybind_include(user=True),
            # Path to fasttext source code
            FASTTEXT_SRC,
        ],
        language='c++',
        extra_compile_args=["-O3"],
    ),
]


# As of Python 3.6, CCompiler has a `has_flag` method.
# cf http://bugs.python.org/issue26689
def has_flag(compiler, flagname):
    """Return a boolean indicating whether a flag name is supported on
    the specified compiler.
    """
    import tempfile
    with tempfile.NamedTemporaryFile('w', suffix='.cpp') as f:
        f.write('int main (int argc, char **argv) { return 0; }')
        try:
            compiler.compile([f.name], extra_postargs=[flagname])
        except setuptools.distutils.errors.CompileError:
            return False
    return True


def cpp_flag(compiler):
    """Return the -std=c++[11/14] compiler flag.
    The c++14 is preferred over c++11 (when it is available).
    """
    if has_flag(compiler, '-std=c++14'):
        return '-std=c++14'
    elif has_flag(compiler, '-std=c++11'):
        return '-std=c++11'
    else:
        raise RuntimeError(
            'Unsupported compiler -- at least C++11 support '
            'is needed!'
        )


class BuildExt(build_ext):
    """A custom build extension for adding compiler-specific options."""
    c_opts = {
        'msvc': ['/EHsc'],
        'unix': [],
    }

    if sys.platform == 'darwin':
        c_opts['unix'] += ['-stdlib=libc++', '-mmacosx-version-min=10.7']

    def build_extensions(self):
        ct = self.compiler.compiler_type
        opts = self.c_opts.get(ct, [])
        if ct == 'unix':
            opts.append('-DVERSION_INFO="%s"' % self.distribution.get_version())
            opts.append(cpp_flag(self.compiler))
            if has_flag(self.compiler, '-fvisibility=hidden'):
                opts.append('-fvisibility=hidden')
        elif ct == 'msvc':
            opts.append(
                '/DVERSION_INFO=\\"%s\\"' % self.distribution.get_version()
            )
        for ext in self.extensions:
            ext.extra_compile_args = opts
        build_ext.build_extensions(self)


setup(
    name='fastTextpy',
    version=__version__,
    author='Christian Puhrsch',
    author_email='cpuhrsch@fb.com',
    description='fastText Python bindings',
    long_description='',
    ext_modules=ext_modules,
    url='https://github.com/facebookresearch/fastText',
    license='BSD',
    install_requires=['pybind11>=2.2', "setuptools >= 0.7.0"],
    cmdclass={'build_ext': BuildExt},
    packages=[str('fastText')],
    package_dir={str(''): str('python')},
    zip_safe=False
)