import os
import re
import shutil
import stat
import tempfile
from contextlib import contextmanager
from pathlib import Path
from typing import Any
from typing import Callable
from typing import Dict
from typing import Iterator
from typing import List
from typing import Optional

from pkm_main.config.config import Config
from pkm_buildsys.packages.package import Package

try:
    from collections.abc import Mapping
except ImportError:
    from collections import Mapping

_canonicalize_regex = re.compile("[-_]+")


def canonicalize_name(name: str) -> str:
    return _canonicalize_regex.sub("-", name).lower()


def module_name(name: str) -> str:
    return canonicalize_name(name).replace(".", "_").replace("-", "_")


def _del_ro(action: Callable, name: str, exc: Exception) -> None:
    os.chmod(name, stat.S_IWRITE)
    os.remove(name)


@contextmanager
def temporary_directory(*args: Any, **kwargs: Any) -> Iterator[str]:
    name = tempfile.mkdtemp(*args, **kwargs)

    yield name

    shutil.rmtree(name, onerror=_del_ro)


def get_cert(config: Config, repository_name: str) -> Optional[Path]:
    cert = config.get(f"certificates.{repository_name}.cert")
    if cert:
        return Path(cert)
    else:
        return None


def get_client_cert(config: Config, repository_name: str) -> Optional[Path]:
    client_cert = config.get(f"certificates.{repository_name}.client-cert")
    if client_cert:
        return Path(client_cert)
    else:
        return None


def _on_rm_error(func: Callable, path: str, exc_info: Exception) -> None:
    if not os.path.exists(path):
        return

    os.chmod(path, stat.S_IWRITE)
    func(path)


def safe_rmtree(path: str) -> None:
    if Path(path).is_symlink():
        return os.unlink(str(path))

    shutil.rmtree(path, onerror=_on_rm_error)


def merge_dicts(d1: Dict, d2: Dict) -> None:
    for k in d2.keys():
        if k in d1 and isinstance(d1[k], dict) and isinstance(d2[k], Mapping):
            merge_dicts(d1[k], d2[k])
        else:
            d1[k] = d2[k]


# def download_file(
#         url: str,
#         dest: str,
#         session: Optional[requests.Session] = None,
#         chunk_size: int = 1024,
# ) -> None:
#     get = requests.get if not session else session.get
#
#     with get(url, stream=True) as response:
#         response.raise_for_status()
#
#         with open(dest, "wb") as f:
#             for chunk in response.iter_content(chunk_size=chunk_size):
#                 if chunk:
#                     f.write(chunk)
#

def get_package_version_display_string(
        package: Package, root: Optional[Path] = None
) -> str:
    if package.source_type in ["file", "directory", "sibling"] and root:
        return "{} {}".format(
            package.version,
            Path(os.path.relpath(package.source_url, root.as_posix())).as_posix(),
        )

    return package.full_pretty_version


def paths_csv(paths: List[Path]) -> str:
    return ", ".join('"{}"'.format(str(c)) for c in paths)


def is_dir_writable(path: Path, create: bool = False) -> bool:
    try:
        if not path.exists():
            if not create:
                return False
            path.mkdir(parents=True, exist_ok=True)

        with tempfile.TemporaryFile(dir=str(path)):
            pass
    except OSError:
        return False
    else:
        return True
