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

from distutils.spawn import find_executable
from distutils import sysconfig, log
import setuptools
import setuptools.command.build_py
import setuptools.command.develop
import setuptools.command.build_ext

from collections import namedtuple
import os
import shlex
import subprocess
import sys
from textwrap import dedent

TOP_DIR = os.path.realpath(os.path.dirname(__file__))
SRC_DIR = os.path.join(TOP_DIR, 'caffe2')

install_requires = []
setup_requires = []
tests_require = []

################################################################################
# Pre Check
################################################################################

assert find_executable('cmake'), 'Could not find "cmake" executable!'
assert find_executable('make'), 'Could not find "make" executable!'

################################################################################
# Version
################################################################################

try:
    git_version = subprocess.check_output(['git', 'describe', '--tags', 'HEAD'],
                                          cwd=TOP_DIR).decode('ascii').strip()
except subprocess.CalledProcessError:
    git_version = None

with open(os.path.join(TOP_DIR, 'VERSION_NUMBER')) as version_file:
    VersionInfo = namedtuple('VersionInfo', ['version', 'git_version'])(
        version=version_file.read().strip(),
        git_version=git_version
    )

################################################################################
# Customized commands
################################################################################


class Caffe2Command(setuptools.Command):
    user_options = []

    def initialize_options(self):
        pass

    def finalize_options(self):
        pass


class create_version(Caffe2Command):
    def run(self):
        with open(os.path.join(SRC_DIR, 'version.py'), 'w') as f:
            f.write(dedent('''
            version = '{version}'
            git_version = '{git_version}'
            '''.format(**dict(VersionInfo._asdict()))))


class build_py(setuptools.command.build_py.build_py):
    def run(self):
        self.run_command('create_version')
        setuptools.command.build_py.build_py.run(self)


class develop(setuptools.command.develop.develop):
    def run(self):
        raise RuntimeError('develop mode is not supported!')


class build_ext(setuptools.command.build_ext.build_ext):
    def _build_with_cmake(self):
        build_temp = os.path.realpath(self.build_temp)
        build_lib = os.path.realpath(self.build_lib)

        if 'CMAKE_INSTALL_DIR' not in os.environ:
            cmake_install_dir = os.path.join(build_temp, 'cmake_install')

            py_exe = sys.executable
            py_inc = sysconfig.get_python_inc()

            if 'CMAKE_ARGS' in os.environ:
                cmake_args = shlex.split(os.environ['CMAKE_ARGS'])
                # prevent crossfire with downstream scripts
                del os.environ['CMAKE_ARGS']
            else:
                cmake_args = []
            log.info('CMAKE_ARGS: {}'.format(cmake_args))

            self.compiler.spawn([
                os.path.join(TOP_DIR, 'scripts', 'build_local.sh'),
                '-DBUILD_SHARED_LIBS=OFF',
                # TODO: Investigate why BUILD_SHARED_LIBS=OFF USE_GLOO=ON
                # will cause error 'target "gloo" that is not in the
                # export set' in cmake.
                '-DUSE_GLOO=OFF',
                '-DCMAKE_INSTALL_PREFIX:PATH={}'.format(cmake_install_dir),
                '-DPYTHON_EXECUTABLE:FILEPATH={}'.format(py_exe),
                '-DPYTHON_INCLUDE_DIR={}'.format(py_inc),
                '-DBUILD_TEST=OFF',
                '-BUILD_BENCHMARK=OFF',
                '-DBUILD_BINARY=OFF',
                TOP_DIR
            ] + cmake_args)
            # This is assuming build_local.sh will use TOP_DIR/build
            # as the cmake build directory
            self.compiler.spawn([
                'make',
                '-C', os.path.join(TOP_DIR, 'build'),
                'install'
            ])
        else:
            cmake_install_dir = os.environ['CMAKE_INSTALL_DIR']

        for d in ['caffe', 'caffe2']:
            self.copy_tree(os.path.join(cmake_install_dir, d),
                           os.path.join(build_lib, d))

    def get_outputs(self):
        return [os.path.join(self.build_lib, d)
                for d in ['caffe', 'caffe2']]

    def build_extensions(self):
        assert len(self.extensions) == 1
        self._build_with_cmake()


cmdclass = {
    'create_version': create_version,
    'build_py': build_py,
    'develop': develop,
    'build_ext': build_ext,
}

################################################################################
# Extensions
################################################################################

ext_modules = [setuptools.Extension(str('caffe2-ext'), [])]

################################################################################
# Packages
################################################################################

packages = []

install_requires.extend(['protobuf',
                         'numpy',
                         'flask',
                         'future',
                         'graphviz',
                         'hypothesis',
                         'jupyter',
                         'matplotlib',
                         'pydot',
                         'python-nvd3',
                         'pyyaml',
                         'requests',
                         'scikit-image',
                         'scipy',
                         'setuptools',
                         'six',
                         'tornado'])

################################################################################
# Test
################################################################################

setup_requires.append('pytest-runner')
tests_require.extend(['pytest-cov', 'hypothesis'])

################################################################################
# Final
################################################################################

setuptools.setup(
    name='caffe2',
    version=VersionInfo.version,
    description='Caffe2',
    ext_modules=ext_modules,
    cmdclass=cmdclass,
    packages=packages,
    install_requires=install_requires,
    setup_requires=setup_requires,
    tests_require=tests_require,
    author='jiayq',
    author_email='jiayq@fb.com',
    url='https://caffe2.ai',
)