#!/usr/bin/env python3
#
# Copyright (c)  2022  Xiaomi Corporation (author: Wei Kang)

import glob
import os
import re
import shutil
import sys

import setuptools
from setuptools.command.build_ext import build_ext

cur_dir = os.path.dirname(os.path.abspath(__file__))


def cmake_extension(name, *args, **kwargs) -> setuptools.Extension:
    kwargs["language"] = "c++"
    sources = []
    return setuptools.Extension(name, sources, *args, **kwargs)


class BuildExtension(build_ext):
    def build_extension(self, ext: setuptools.extension.Extension):
        # build/temp.linux-x86_64-3.8
        build_dir = self.build_temp
        os.makedirs(build_dir, exist_ok=True)

        # build/lib.linux-x86_64-3.8
        os.makedirs(self.build_lib, exist_ok=True)

        ft_dir = os.path.dirname(os.path.abspath(__file__))

        cmake_args = os.environ.get("FT_CMAKE_ARGS", "")
        make_args = os.environ.get("FT_MAKE_ARGS", "")
        system_make_args = os.environ.get("MAKEFLAGS", "")

        if cmake_args == "":
            cmake_args = "-DCMAKE_BUILD_TYPE=Release"

        if make_args == "" and system_make_args == "":
            print("For fast compilation, run:")
            print('export FT_MAKE_ARGS="-j"; python setup.py install')

        if "PYTHON_EXECUTABLE" not in cmake_args:
            print(f"Setting PYTHON_EXECUTABLE to {sys.executable}")
            cmake_args += f" -DPYTHON_EXECUTABLE={sys.executable}"

        build_cmd = f"""
            cd {self.build_temp}

            cmake {cmake_args} {ft_dir}

            make {make_args} _fast_rnnt
        """
        print(f"build command is:\n{build_cmd}")

        ret = os.system(build_cmd)
        if ret != 0:
            raise Exception(
                "\nBuild fast_rnnt failed. Please check the error "
                "message.\n"
                "You can ask for help by creating an issue on GitHub.\n"
                "\nClick:\n"
                "\thttps://github.com/danpovey/fast_rnnt/issues/new\n"  # noqa
            )
        lib_so = glob.glob(f"{build_dir}/lib/*.so*")
        for so in lib_so:
            print(f"Copying {so} to {self.build_lib}/")
            shutil.copy(f"{so}", f"{self.build_lib}/")

        # macos
        lib_so = glob.glob(f"{build_dir}/lib/*.dylib*")
        for so in lib_so:
            print(f"Copying {so} to {self.build_lib}/")
            shutil.copy(f"{so}", f"{self.build_lib}/")


def read_long_description():
    with open("README.md", encoding="utf8") as f:
        readme = f.read()
    return readme


def get_package_version():
    with open("CMakeLists.txt") as f:
        content = f.read()

    latest_version = re.search(r"set\(FT_VERSION (.*)\)", content).group(1)
    latest_version = latest_version.strip('"')
    return latest_version

def get_requirements():
    with open("requirements.txt", encoding="utf8") as f:
        requirements = f.read().splitlines()

    return requirements

package_name = "fast_rnnt"

with open(
    "fast_rnnt/python/fast_rnnt/__init__.py", "a"
) as f:
    f.write(f"__version__ = '{get_package_version()}'\n")

setuptools.setup(
    name=package_name,
    version=get_package_version(),
    author="Dan Povey",
    author_email="dpovey@gmail.com",
    package_dir={
        package_name: "fast_rnnt/python/fast_rnnt",
    },
    packages=[package_name],
    url="https://github.com/danpovey/fast_rnnt",
    description="Fast and memory-efficient RNN-T loss.",
    long_description=read_long_description(),
    long_description_content_type="text/markdown",
    install_requires=get_requirements(),
    ext_modules=[cmake_extension("_fast_rnnt")],
    cmdclass={"build_ext": BuildExtension},
    zip_safe=False,
    classifiers=[
        "Programming Language :: C++",
        "Programming Language :: Python",
        "Topic :: Scientific/Engineering :: Artificial Intelligence",
    ],
    license="Apache licensed, as found in the LICENSE file",
)