# MIT License
#
# Copyright (c) 2020 Brett Graves
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.

import xml.etree.cElementTree as ET


def shouldIgnore(s):
    """Should we ignore the key s?
    (Right now, returns true if s takes the form
    "__xxxxx...", prepended by two '_' chars
    """
    return len(s) > 1 and s[:2] == "__"


def woodChipper(tree):
    """Given a tree structure,
    sort out the leaves from the subtrees (and also aggregate all the other junk)
    """
    leaves = []
    trees = []

    for k, v in tree.items():

        if not shouldIgnore(k):

            # Pull out the subtrees
            if isinstance(v, dict):
                trees.append((k, v))

            # Pull out the leaves
            else:
                leaves.append((k, str(v)))

    return leaves, trees


def _transposeTreeHelper(tree, name="unnamed_tree", work=None):
    """Recursive steps of vvvv"""

    # Sort all this stuff out
    leaves, trees = woodChipper(tree)

    # Create this current object
    root = ET.SubElement(work, name, attrib=dict(leaves))

    # Now add all of our branches
    for name, subtree in trees:

        # Now pass this root object off to the helper
        _transposeTreeHelper(subtree, name=name, work=root)


def transposeTree(
    tree,
    name="unnamed_tree",
    stringify=True,
):
    """Give me a nested dictionary structure, where at each level:

    - Leaves should become XML attributes
    - Subtrees become subtags
    """

    # Sort all this stuff out
    leaves, trees = woodChipper(tree)

    # Create the root element, and add any needed leaves
    root = ET.Element(name, attrib=dict(leaves))

    # Now add all of our branches
    for name, subtree in trees:

        # Now pass this root object off to the helper
        _transposeTreeHelper(subtree, name=name, work=root)

    # And return the new tree
    if stringify:
        return ET.tostring(root)

    # Return raw tree
    else:
        return root


def fixTag(tag):
    return tag.split("}", 1)[-1]


def parseTree(tree):

    if isinstance(tree, str):
        tree = ET.fromstring(tree)

    if tree is None:
        return {}

    x = tree.attrib

    for child in tree:
        x = {**x, **parseTree(child)}

    return {fixTag(tree.tag): x}
