import sys
import os
import shutil
import pathlib
import multiprocessing

from math import ceil

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


PROJECT_NAME = "aidge_core"

SETUP_DIR = pathlib.Path(__file__).parent

class CMakeExtension(Extension):
    def __init__(self, name):
        super().__init__(name, sources=[])


class CMakeBuild(build_ext):
    def __init__(self, dist, *args, **kwargs):
        super().__init__(dist, *args, **kwargs)
        # Detect editable_mode for old versions of setuptools
        if not hasattr(self, "editable_mode"):
            if hasattr(dist, "commands"):
                self.editable_mode = "develop" in dist.commands
            else:
                self.editable_mode = False

    def run(self):
        # This lists the number of processors available on the machine
        # The compilation will use half of them
        max_jobs = str(ceil(multiprocessing.cpu_count() / 2))

        cwd = pathlib.Path().absolute()

        build_temp = cwd / "build"
        if not build_temp.exists():
            build_temp.mkdir(parents=True, exist_ok=True)

        build_lib = pathlib.Path(self.build_lib)
        if not build_lib.exists():
            build_lib.mkdir(parents=True, exist_ok=True)

        package_prefix = build_lib if not self.editable_mode else SETUP_DIR
        pybind_install_prefix = (package_prefix / PROJECT_NAME).absolute()

        os.chdir(str(build_temp))

        compile_type = os.environ.get("AIDGE_PYTHON_BUILD_TYPE", "Release")
        install_path = (
            os.path.join(sys.prefix, "lib", "libAidge")
            if "AIDGE_INSTALL" not in os.environ
            else os.environ["AIDGE_INSTALL"]
        )
        build_gen = os.environ.get("AIDGE_BUILD_GEN", "")
        build_gen_opts = (
            ["-G", build_gen]
            if build_gen
            else []
        )
        test_onoff = os.environ.get("AIDGE_BUILD_TEST", "OFF")

        self.spawn(
            [
                "cmake",
                *build_gen_opts,
                str(cwd),
                f"-DTEST={test_onoff}",
                f"-DCMAKE_INSTALL_PREFIX:PATH={install_path}",
                f"-DCMAKE_BUILD_TYPE={compile_type}",
                "-DPYBIND=ON",
                f"-DPYBIND_INSTALL_PREFIX:PATH={pybind_install_prefix}",
                "-DCMAKE_EXPORT_COMPILE_COMMANDS=ON",
                "-DCOVERAGE=OFF",
            ]
        )

        if not self.dry_run:
            self.spawn(
                ["cmake", "--build", ".", "--config", compile_type, "-j", max_jobs]
            )
            self.spawn(["cmake", "--install", ".", "--config", compile_type])
        os.chdir(str(cwd))


if __name__ == "__main__":
    setup(
        ext_modules=[CMakeExtension(PROJECT_NAME)],
        cmdclass={
            "build_ext": CMakeBuild,
        },
        zip_safe=False,
    )