import pathlib
import warnings
from typing import Any, Callable, Dict, Optional, Sequence, Tuple, Type, Union

__all__ = (
    "Types",
    "SYSTEMD_SERVICE_CONFIG",
    "SYSTEMD_NETWORK_CONFIG",
    "SYSTEMD_CONFIG_ROOT",
    "systemdbool",
    "AnsibleParameter",
)


SYSTEMD_CONFIG_ROOT = pathlib.Path("/etc/systemd")
SYSTEMD_NETWORK_CONFIG = SYSTEMD_CONFIG_ROOT / "network"
SYSTEMD_SERVICE_CONFIG = SYSTEMD_CONFIG_ROOT / "system"

AnsibleParameter = Dict[str, Any]


def wrap_func(func, **updates):
    def wrapper(*args, **kwargs):
        return func(*args, **kwargs)

    attrs = frozenset(
        ('__module__', '__name__', '__qualname__', '__doc__', '__annotations__', '__type_params__')
    ) - frozenset(updates.keys())
    for attr in attrs:
        try:
            value = getattr(func, attr)
        except AttributeError:
            pass
        else:
            setattr(wrapper, attr, value)
    for attr, value in updates.items():
        setattr(wrapper, attr, value)
    wrapper.__dict__.update(func.__dict__)
    setattr(wrapper, "__wrapped__", func)
    return wrapper


GENERIC_DOC = """Returns an dictionary for the Ansible {type} type."""


def default(name: str):
    def wrapped(
        required: bool = False,
        help: Optional[str] = None,
        choices: Optional[Sequence] = None,
        default: Optional[Any] = None,
    ) -> AnsibleParameter:
        option: AnsibleParameter = dict(type=name, required=required)
        if choices is not None:
            option["choices"] = choices
        if default is not None:
            option["default"] = default
        if help is not None:
            option["description"] = help.split("\n")
        return option

    return wrapped


class meta(type):
    def __new__(cls, clsname, bases, attrs):
        types = frozenset(
            (
                "str",
                "bool",
                "int",
                "float",
                "path",
                "raw",
                "jsonarg",
                "json",
                "bytes",
                "dict",
                "list",
                "bits",
            )
        )
        for attr in types - set(attrs.keys()):
            attrs[attr] = wrap_func(
                default(attr), __doc__=GENERIC_DOC.format(type=attr), __name__=attr, __qualname__=f"{clsname}.{attr}"
            )
        attrs["__slots__"] = ()
        return super().__new__(cls, clsname, bases, attrs)


class Types(metaclass=meta):

    def list(  # type: ignore[misc]
        elements: Union[Type[object], str, AnsibleParameter],
        required: bool = False,
        help: Optional[str] = None,
    ) -> AnsibleParameter:
        """Wrapper for the Ansible list type

        Args:
            elements: The type of the elements
            required: if the item is absolutly required
            help: an helptext for the ansible-doc
        """
        option: AnsibleParameter = dict(type="list", required=required)
        if not isinstance(elements, (str, dict)):
            option["elements"] = elements.__name__
        elif isinstance(elements, dict):
            option["elements"] = elements["type"]
            if elements["type"] == "dict":
                option["options"] = dict()
                for name, value in elements["option"].items():
                    option["options"][name] = value
                    if "description" not in option["options"][name]:
                        warnings.warn(  # pragma: nocover
                            f"helptext of option {name} is unset."
                            " Ansible requires suboptions to have an documentation"
                        )
        if help is not None:
            option["description"] = help.split("\n")
        return option

    def dict(required: bool = False, help: Optional[str] = None, **options: AnsibleParameter) -> AnsibleParameter:  # type: ignore[misc]
        """Wrapper for the Ansible dict type

        Args:
            required: if the item is absolutly required
            help: an helptext for the ansible-doc
            options: The individual options that this parameter has
        """
        option: AnsibleParameter = dict(type="dict", required=required)
        option["options"] = options
        if help is not None:
            option["description"] = help.split("\n")
        return option


def systemdbool(b: Union[bool, str]) -> str:
    """Converts values into things systemd can parse"""
    if b is True:
        return "yes"
    elif b is False:
        return "no"
    return b


def modspec(
    argument_spec: Dict[str, Dict[str, Any]],
    mutually_exclusive: Sequence[Tuple[str, ...]] = (),
    required_together: Sequence[Tuple[str, ...]] = (),
    required_one_of: Sequence[Tuple[str, ...]] = (),
    required_if: Sequence[Union[Tuple[str, Any, Tuple[str, ...]], Tuple[str, Any, Tuple[str, ...], bool]]] = (),
    required_by: Dict[str, Union[str, Tuple[str, ...]]] = {},
) -> Dict[str, Any]:  # pragma: nocover
    return dict(
        argument_spec=argument_spec,
        mutually_exclusive=mutually_exclusive,
        required_together=required_together,
        required_one_of=required_one_of,
        required_if=required_if,
        required_by=required_by,
    )


def joindict(*items: dict) -> dict:
    """merges one or more dictionaries into one"""
    odict = dict()
    for item in items:
        for key, value in item.items():
            odict[key] = value
    return odict