""" Dual ParserNode implementation """
from typing import Any
from typing import Generic
from typing import Iterable
from typing import List
from typing import Optional
from typing import Set
from typing import Tuple
from typing import Type
from typing import TYPE_CHECKING
from typing import TypeVar

from certbot_apache._internal import apacheparser
from certbot_apache._internal import assertions
from certbot_apache._internal import augeasparser
from certbot_apache._internal import interfaces

if TYPE_CHECKING:
    from certbot_apache._internal.apacheparser import ApacheParserNode  # pragma: no cover
    from certbot_apache._internal.augeasparser import AugeasParserNode  # pragma: no cover

GenericAugeasParserNode = TypeVar("GenericAugeasParserNode", bound="AugeasParserNode")
GenericApacheParserNode = TypeVar("GenericApacheParserNode", bound="ApacheParserNode")
GenericDualNode = TypeVar("GenericDualNode", bound="DualNodeBase")


class DualNodeBase(Generic[GenericAugeasParserNode, GenericApacheParserNode]):
    """ Dual parser interface for in development testing. This is used as the
    base class for dual parser interface classes. This class handles runtime
    attribute value assertions."""

    def __init__(self, primary: GenericAugeasParserNode,
                 secondary: GenericApacheParserNode) -> None:
        self.primary = primary
        self.secondary = secondary

    def save(self, msg: str) -> None:  # pragma: no cover
        """ Call save for both parsers """
        self.primary.save(msg)
        self.secondary.save(msg)

    def __getattr__(self, aname: str) -> Any:
        """ Attribute value assertion """
        firstval = getattr(self.primary, aname)
        secondval = getattr(self.secondary, aname)
        exclusions = [
            # Metadata will inherently be different, as ApacheParserNode does
            # not have Augeas paths and so on.
            aname == "metadata",
            callable(firstval)
        ]
        if not any(exclusions):
            assertions.assertEqualSimple(firstval, secondval)
        return firstval

    def find_ancestors(self, name: str) -> List["DualNodeBase"]:
        """ Traverses the ancestor tree and returns ancestors matching name """
        return self._find_helper(DualBlockNode, "find_ancestors", name)

    def _find_helper(self, nodeclass: Type[GenericDualNode], findfunc: str, search: str,
                     **kwargs: Any) -> List[GenericDualNode]:
        """A helper for find_* functions. The function specific attributes should
        be passed as keyword arguments.

        :param interfaces.ParserNode nodeclass: The node class for results.
        :param str findfunc: Name of the find function to call
        :param str search: The search term
        """

        primary_res = getattr(self.primary, findfunc)(search, **kwargs)
        secondary_res = getattr(self.secondary, findfunc)(search, **kwargs)

        # The order of search results for Augeas implementation cannot be
        # assured.

        pass_primary = assertions.isPassNodeList(primary_res)
        pass_secondary = assertions.isPassNodeList(secondary_res)
        new_nodes = []

        if pass_primary and pass_secondary:
            # Both unimplemented
            new_nodes.append(nodeclass(primary=primary_res[0],
                                       secondary=secondary_res[0]))  # pragma: no cover
        elif pass_primary:
            for c in secondary_res:
                new_nodes.append(nodeclass(primary=primary_res[0],
                                           secondary=c))
        elif pass_secondary:
            for c in primary_res:
                new_nodes.append(nodeclass(primary=c,
                                           secondary=secondary_res[0]))
        else:
            assert len(primary_res) == len(secondary_res)
            matches = self._create_matching_list(primary_res, secondary_res)
            for p, s in matches:
                new_nodes.append(nodeclass(primary=p, secondary=s))

        return new_nodes


class DualCommentNode(DualNodeBase[augeasparser.AugeasCommentNode,
                                   apacheparser.ApacheCommentNode]):
    """ Dual parser implementation of CommentNode interface """

    def __init__(self, **kwargs: Any) -> None:
        """ This initialization implementation allows ordinary initialization
        of CommentNode objects as well as creating a DualCommentNode object
        using precreated or fetched CommentNode objects if provided as optional
        arguments primary and secondary.

        Parameters other than the following are from interfaces.CommentNode:

        :param CommentNode primary: Primary pre-created CommentNode, mainly
            used when creating new DualParser nodes using add_* methods.
        :param CommentNode secondary: Secondary pre-created CommentNode
        """

        kwargs.setdefault("primary", None)
        kwargs.setdefault("secondary", None)
        primary = kwargs.pop("primary")
        secondary = kwargs.pop("secondary")

        if primary or secondary:
            assert primary and secondary
            super().__init__(primary, secondary)
        else:
            super().__init__(augeasparser.AugeasCommentNode(**kwargs),
                             apacheparser.ApacheCommentNode(**kwargs))

        assertions.assertEqual(self.primary, self.secondary)


class DualDirectiveNode(DualNodeBase[augeasparser.AugeasDirectiveNode,
                                     apacheparser.ApacheDirectiveNode]):
    """ Dual parser implementation of DirectiveNode interface """

    parameters: str

    def __init__(self, **kwargs: Any) -> None:
        """ This initialization implementation allows ordinary initialization
        of DirectiveNode objects as well as creating a DualDirectiveNode object
        using precreated or fetched DirectiveNode objects if provided as optional
        arguments primary and secondary.

        Parameters other than the following are from interfaces.DirectiveNode:

        :param DirectiveNode primary: Primary pre-created DirectiveNode, mainly
            used when creating new DualParser nodes using add_* methods.
        :param DirectiveNode secondary: Secondary pre-created DirectiveNode
        """

        kwargs.setdefault("primary", None)
        kwargs.setdefault("secondary", None)
        primary = kwargs.pop("primary")
        secondary = kwargs.pop("secondary")

        if primary or secondary:
            assert primary and secondary
            super().__init__(primary, secondary)
        else:
            super().__init__(augeasparser.AugeasDirectiveNode(**kwargs),
                             apacheparser.ApacheDirectiveNode(**kwargs))

        assertions.assertEqual(self.primary, self.secondary)

    def set_parameters(self, parameters: Iterable[str]) -> None:
        """ Sets parameters and asserts that both implementation successfully
        set the parameter sequence """

        self.primary.set_parameters(parameters)
        self.secondary.set_parameters(parameters)
        assertions.assertEqual(self.primary, self.secondary)


class DualBlockNode(DualNodeBase[augeasparser.AugeasBlockNode,
                                 apacheparser.ApacheBlockNode]):
    """ Dual parser implementation of BlockNode interface """

    def __init__(self, **kwargs: Any) -> None:
        """ This initialization implementation allows ordinary initialization
        of BlockNode objects as well as creating a DualBlockNode object
        using precreated or fetched BlockNode objects if provided as optional
        arguments primary and secondary.

        Parameters other than the following are from interfaces.BlockNode:

        :param BlockNode primary: Primary pre-created BlockNode, mainly
            used when creating new DualParser nodes using add_* methods.
        :param BlockNode secondary: Secondary pre-created BlockNode
        """

        kwargs.setdefault("primary", None)
        kwargs.setdefault("secondary", None)
        primary: Optional[augeasparser.AugeasBlockNode] = kwargs.pop("primary")
        secondary: Optional[apacheparser.ApacheBlockNode] = kwargs.pop("secondary")

        if primary or secondary:
            assert primary and secondary
            super().__init__(primary, secondary)
        else:
            super().__init__(augeasparser.AugeasBlockNode(**kwargs),
                             apacheparser.ApacheBlockNode(**kwargs))

        assertions.assertEqual(self.primary, self.secondary)

    def add_child_block(self, name: str, parameters: Optional[List[str]] = None,
                        position: Optional[int] = None) -> "DualBlockNode":
        """ Creates a new child BlockNode, asserts that both implementations
        did it in a similar way, and returns a newly created DualBlockNode object
        encapsulating both of the newly created objects """

        primary_new = self.primary.add_child_block(name, parameters, position)
        secondary_new = self.secondary.add_child_block(name, parameters, position)
        assertions.assertEqual(primary_new, secondary_new)
        return DualBlockNode(primary=primary_new, secondary=secondary_new)

    def add_child_directive(self, name: str, parameters: Optional[List[str]] = None,
                            position: Optional[int] = None) -> DualDirectiveNode:
        """ Creates a new child DirectiveNode, asserts that both implementations
        did it in a similar way, and returns a newly created DualDirectiveNode
        object encapsulating both of the newly created objects """

        primary_new = self.primary.add_child_directive(name, parameters, position)
        secondary_new = self.secondary.add_child_directive(name, parameters, position)
        assertions.assertEqual(primary_new, secondary_new)
        return DualDirectiveNode(primary=primary_new, secondary=secondary_new)

    def add_child_comment(self, comment: str = "",
                          position: Optional[int] = None) -> DualCommentNode:
        """ Creates a new child CommentNode, asserts that both implementations
        did it in a similar way, and returns a newly created DualCommentNode
        object encapsulating both of the newly created objects """

        primary_new = self.primary.add_child_comment(comment=comment, position=position)
        secondary_new = self.secondary.add_child_comment(name=comment, position=position)
        assertions.assertEqual(primary_new, secondary_new)
        return DualCommentNode(primary=primary_new, secondary=secondary_new)

    def _create_matching_list(self, primary_list: Iterable[interfaces.ParserNode],
                              secondary_list: Iterable[interfaces.ParserNode]
                              ) -> List[Tuple[interfaces.ParserNode, interfaces.ParserNode]]:
        """ Matches the list of primary_list to a list of secondary_list and
        returns a list of tuples. This is used to create results for find_
        methods.

        This helper function exists, because we cannot ensure that the list of
        search results returned by primary.find_* and secondary.find_* are ordered
        in a same way. The function pairs the same search results from both
        implementations to a list of tuples.
        """

        matched = []
        for p in primary_list:
            match = None
            for s in secondary_list:
                try:
                    assertions.assertEqual(p, s)
                    match = s
                    break
                except AssertionError:
                    continue
            if match:
                matched.append((p, match))
            else:
                raise AssertionError("Could not find a matching node.")
        return matched

    def find_blocks(self, name: str, exclude: bool = True) -> List["DualBlockNode"]:
        """
        Performs a search for BlockNodes using both implementations and does simple
        checks for results. This is built upon the assumption that unimplemented
        find_* methods return a list with a single assertion passing object.
        After the assertion, it creates a list of newly created DualBlockNode
        instances that encapsulate the pairs of returned BlockNode objects.
        """

        return self._find_helper(DualBlockNode, "find_blocks", name,
                                 exclude=exclude)

    def find_directives(self, name: str, exclude: bool = True) -> List[DualDirectiveNode]:
        """
        Performs a search for DirectiveNodes using both implementations and
        checks the results. This is built upon the assumption that unimplemented
        find_* methods return a list with a single assertion passing object.
        After the assertion, it creates a list of newly created DualDirectiveNode
        instances that encapsulate the pairs of returned DirectiveNode objects.
        """

        return self._find_helper(DualDirectiveNode, "find_directives", name,
                                 exclude=exclude)

    def find_comments(self, comment: str) -> List[DualCommentNode]:
        """
        Performs a search for CommentNodes using both implementations and
        checks the results. This is built upon the assumption that unimplemented
        find_* methods return a list with a single assertion passing object.
        After the assertion, it creates a list of newly created DualCommentNode
        instances that encapsulate the pairs of returned CommentNode objects.
        """

        return self._find_helper(DualCommentNode, "find_comments", comment)

    def delete_child(self, child: "DualBlockNode") -> None:
        """Deletes a child from the ParserNode implementations. The actual
        ParserNode implementations are used here directly in order to be able
        to match a child to the list of children."""

        self.primary.delete_child(child.primary)
        self.secondary.delete_child(child.secondary)

    def unsaved_files(self) -> Set[str]:
        """ Fetches the list of unsaved file paths and asserts that the lists
        match """
        primary_files = self.primary.unsaved_files()
        secondary_files = self.secondary.unsaved_files()
        assertions.assertEqualSimple(primary_files, secondary_files)

        return primary_files

    def parsed_paths(self) -> List[str]:
        """
        Returns a list of file paths that have currently been parsed into the parser
        tree. The returned list may include paths with wildcard characters, for
        example: ['/etc/apache2/conf.d/*.load']

        This is typically called on the root node of the ParserNode tree.

        :returns: list of file paths of files that have been parsed
        """

        primary_paths = self.primary.parsed_paths()
        secondary_paths = self.secondary.parsed_paths()
        assertions.assertEqualPathsList(primary_paths, secondary_paths)
        return primary_paths
