fetch

#! /usr/bin/env -S python3 -u

# Copyright (c) 2023, Eugene Gershnik
# SPDX-License-Identifier: GPL-3.0-or-later

# pylint: disable=wrong-import-position

import sys
if sys.version_info < (3, 11):
    raise RuntimeError('Python 3.11 or greater is required to build this project')

import shutil
import subprocess
import json
from pathlib import Path
from urllib.request import urlretrieve

components = {
    'objc-helpers': {
        'ver': 'v3.8.0',
        'url': 'https://github.com/gershnik/objc-helpers/tarball/{ver}',
        'unpacker': {
            'type': 'tar',
            'strip': 1
        },
        'dir': 'objc-helpers',
        'verFile': 'VERSION',
        'generateVerFile': True
    },
    'isptr': {
        'ver': 'v1.13',
        'url': 'https://github.com/gershnik/intrusive_shared_ptr/tarball/{ver}',
        'unpacker': {
            'type': 'tar',
            'strip': 1
        },
        'dir': 'isptr',
        'verFile': 'VERSION',
        'generateVerFile': True
    }
}


MYDIR = Path(__file__).parent
EXTERNAL_DIR = MYDIR / 'External'


def ver_to_list(ver):
    return [i for i in ver.split('.')]
    
def get_version_from_file(path):
    existing_ver = None
    if path.is_file():
        existing_ver = ver_to_list(path.read_text().rstrip())
    return existing_ver

def check_up_to_date(name, component):
    directory = EXTERNAL_DIR / component['dir']
    up_to_date = False
    
    if component.get('verFile'):
        ver_file = directory / component['verFile']
        required_ver = ver_to_list(component['ver'])
        existing_ver = get_version_from_file(ver_file)
        if existing_ver == required_ver:
            up_to_date = True
    else:
        print(f"Dont know how to detect version of {name}", file=sys.stderr)
        sys.exit(1)
        
    if not up_to_date:
        print(f'{name} not up to date, required {required_ver}, existing {existing_ver}')
    else:
        print(f'{name} is up to date')
    return up_to_date
    
def untar(name, component, archive):
    directory = EXTERNAL_DIR / component.get('dir', name)
    if archive.suffix in ('.tgz', '.gz'):
        comp = 'z'
    elif archive.suffix in ('.tbz', '.bz'):
        comp = 'j'
    else:
        comp = ''

    command = ['/usr/bin/tar', '-C', directory, f'-x{comp}f', archive]
    subst = component['unpacker'].get('subst')
    if subst is not None:
        command += ['-s', subst]
    strip = component['unpacker'].get('strip')
    if strip is not None:
        command += ['--strip-components', str(strip)]

    subprocess.run(command, check=True)

def fetch_url(name, component, unpacker):
    directory = EXTERNAL_DIR / component['dir']
    
    shutil.rmtree(directory, ignore_errors=True)
    if directory.exists():
        print(f'Unable to remove {name} directory', file=sys.stderr)
        sys.exit(1)
    directory.mkdir()
    url = component['url'].format(ver = component['ver'])
    path, _ = urlretrieve(url)
    try:
        unpacker(name, component, Path(path))
        print(f'Installed {name}')
    finally:
        Path(path).unlink()
    generate_ver_file = component.get('generateVerFile', False)
    if generate_ver_file:
        ver_file = directory / component['verFile']
        ver_file.write_text(component['ver'])


def get_fetcher(name, component):
    if component.get('url'):
        return fetch_url
    
    print(f"Dont know how to download {name}", file=sys.stderr)
    sys.exit(1)
        
def get_unpacker(name, component):
    component_type = component['unpacker']['type']
    if component_type == 'tar':
        return untar
    
    print(f"Dont know how to unpack {name}", file=sys.stderr)
    sys.exit(1)

def main():
    local_xcconfig = MYDIR / 'Local.xcconfig'

    if not local_xcconfig.exists():
        min_ver = ''
        try:
            sdk = subprocess.run(['xcrun', '--sdk', 'macosx', '--show-sdk-path'], stdout=subprocess.PIPE,
                                encoding='utf-8', check=True).stdout.strip()
            with open(f'{sdk}/SDKSettings.json', 'rb') as f:
                data = json.load(f)
            min_ver = str(data['SupportedTargets']['macosx']['MinimumDeploymentTarget'])
        except (subprocess.SubprocessError, OSError, json.JSONDecodeError, UnicodeDecodeError, KeyError):
            pass
        local_xcconfig.write_text(f'''\
// Local configuration settings. Do not commit to source control
//
// Configuration settings file format documentation can be found at:
// https://help.apple.com/xcode/#/dev745c5c974
//
// To create signed and notarized installer from Xcode do this:
//TRANSLIT_SIGN_PACKAGE=true
//NOTARIZE_USER=...
//NOTARIZE_PWD=...
//CODE_SIGN_INJECT_BASE_ENTITLEMENTS=NO

// Uncomment the following to set min supported macOS version different from the default
//MACOSX_DEPLOYMENT_TARGET = {min_ver}
''')

    EXTERNAL_DIR.mkdir(parents=True, exist_ok=True)
    for name, component in components.items():
        if check_up_to_date(name, component):
            continue
        fetcher = get_fetcher(name, component)
        unpacker = get_unpacker(name, component)
        fetcher(name, component, unpacker)


if __name__ == '__main__':
    main()