#!/usr/bin/env python3

import multiprocessing
import os
import shutil

import common

class LinuxComponent(common.Component):
    def add_parser_arguments(self, parser):
        parser.add_argument(
            'extra_make_args',
            default=[],
            metavar='extra-make-args',
            nargs='*'
        )

    def do_build(self, args):
        build_dir = self.get_build_dir(args)
        os.makedirs(build_dir, exist_ok=True)
        common.cp(
            os.path.join(common.linux_config_dir, 'buildroot-{}'.format(args.arch)),
            os.path.join(build_dir, '.config'),
        )
        tool = 'gcc'
        gcc = common.get_toolchain_tool(tool)
        prefix = gcc[:-len(tool)]
        common_args = {
            'cwd': common.linux_src_dir,
        }
        ccache = shutil.which('ccache')
        if ccache is not None:
            cc = '{} {}'.format(ccache, gcc)
        else:
            cc = gcc
        common_make_args = [
            'ARCH={}'.format(common.linux_arch),
            'CROSS_COMPILE={}'.format(prefix),
            'CC={}'.format(cc),
            'O={}'.format(build_dir),
        ]
        if args.verbose:
            verbose = ['V=1']
        else:
            verbose = []
        assert common.run_cmd(
            [
                os.path.join(common.linux_src_dir, 'scripts', 'kconfig', 'merge_config.sh'),
                '-m',
                '-O', build_dir,
                os.path.join(build_dir, '.config'),
                os.path.join(common.linux_config_dir, 'min'),
                os.path.join(common.linux_config_dir, 'default'),
            ],
        ) == 0
        assert common.run_cmd(
            (
                [
                    'make',
                    '-j', str(multiprocessing.cpu_count()),
                ] +
                common_make_args +
                [
                    'olddefconfig',
                ]
            ),
            **common_args,
        ) == 0
        assert common.run_cmd(
            (
                [
                    'make',
                    '-j', str(multiprocessing.cpu_count()),
                ] +
                common_make_args +
                verbose +
                args.extra_make_args
            ),
            **common_args,
        ) == 0

    def get_argparse_args(self):
        return {
                'description': '''\
Build the Linux kernel.
'''
        }

    def get_build_dir(self, args):
        return common.linux_build_dir

LinuxComponent().build()