from contextlib import ContextDecorator, ExitStack, contextmanager
from functools import wraps
from unittest.mock import patch

from .forms import get_permissions_forms
from .useracl import get_user_acl

__all__ = ["patch_user_acl"]


class patch_user_acl(ContextDecorator, ExitStack):
    """Testing utility that patches get_user_acl results

    Can be used as decorator or context manager.

    Patch should be a dict or callable.
    """

    _acl_patches = []

    def __init__(self, acl_patch):
        super().__init__()
        self.acl_patch = acl_patch

    def patched_get_user_acl(self, user, cache_versions):
        user_acl = get_user_acl(user, cache_versions)
        self.apply_acl_patches(user, user_acl)
        return user_acl

    def apply_acl_patches(self, user, user_acl):
        for acl_patch in self._acl_patches:
            self.apply_acl_patch(user, user_acl, acl_patch)

    def apply_acl_patch(self, user, user_acl, acl_patch):
        if callable(acl_patch):
            acl_patch(user, user_acl)
        else:
            user_acl.update(acl_patch)

    def __enter__(self):
        super().__enter__()
        self.enter_context(self.enable_acl_patch())
        self.enter_context(self.patch_user_acl())

    @contextmanager
    def enable_acl_patch(self):
        try:
            self._acl_patches.append(self.acl_patch)
            yield
        finally:
            self._acl_patches.pop(-1)

    def patch_user_acl(self):
        return patch(
            "misago.acl.useracl.get_user_acl",
            side_effect=self.patched_get_user_acl,
        )


def mock_form_data(model, data):
    """
    In order for form to don't fail submission, all permission fields need
    to receive values. This function populates data dict with default values
    for permissions, making form validation pass
    """
    for form in get_permissions_forms(model):
        for field in form:
            if field.value() is True:
                data[field.html_name] = 1
            elif field.value() is False:
                data[field.html_name] = 0
            else:
                data[field.html_name] = field.value()
    return data