import json
import logging
from pathlib import Path
import shlex
import subprocess
import sys
from typing import Sequence

_project_root = Path('.').absolute()

def get_project_root() -> Path:
    return _project_root

def set_project_root(path: Path) -> None:
    global _project_root
    _project_root = path

def get_config_cache() -> dict:
    cache_file = get_project_root() / 'cache' / 'config_cache.json'
    if not cache_file.exists():
        return {}

    try:
        with cache_file.open('r') as f:
            cache = json.load(f)
            if not isinstance(cache, dict):
                logging.warning('Config cache is not a dictionary, ignoring it.')
                return {}
            return cache
    except Exception as e:
        logging.error(f'Error while reading config cache: {e}.')
        return {}

def require_project_file() -> None:
    if not (get_project_root() / 'SConstruct').exists():
        logging.error('This command has to be run inside an existing S++ project folder. Exiting.')
        sys.exit(1)

def exec_checked(args: Sequence[str], **kwargs) -> None:
    logging.debug('exec_checked: "%s"', shlex.join(args))
    subprocess.run(args, stdout=sys.stdout, stderr=sys.stderr, check=True, **kwargs)

def exec_get_output(args: Sequence[str], **kwargs) -> str:
    logging.debug('exec_get_output: "%s"', shlex.join(args))
    return subprocess.run(args, text=True, check=True, capture_output=True, **kwargs).stdout

def exec_spp(args: Sequence[str], **kwargs):
    full_cmd = ('scons', '-s', '--disable_auto_update', *args)
    exec_checked(full_cmd, **kwargs)