import gettext

_ = gettext.gettext

import new

import copy

from . import _base

from html5lib.constants import voidElements

moduleCache = {}

def getETreeModule(ElementTreeImplementation):

name = "_" + ElementTreeImplementation.__name__+"builder"

if name in moduleCache:

return moduleCache[name]

else:

mod = new.module("_" + ElementTreeImplementation.__name__+"builder")

objs = getETreeBuilder(ElementTreeImplementation)

mod.__dict__.update(objs)

moduleCache[name] = mod

return mod

def getETreeBuilder(ElementTreeImplementation):

ElementTree = ElementTreeImplementation

class TreeWalker(_base.NonRecursiveTreeWalker):

"""Given the particular ElementTree representation, this implementation,

to avoid using recursion, returns "nodes" as tuples with the following

content:

1. The current element

2. The index of the element relative to its parent

3. A stack of ancestor elements

4. A flag "text", "tail" or None to indicate if the current node is a

text node; either the text or tail of the current element (1)

"""

def getNodeDetails(self, node):

if isinstance(node, tuple): # It might be the root Element

elt, key, parents, flag = node

if flag in ("text", "tail"):

return _base.TEXT, getattr(elt, flag)

else:

node = elt

if not(hasattr(node, "tag")):

node = node.getroot()

if node.tag in ("<DOCUMENT_ROOT>", "<DOCUMENT_FRAGMENT>"):

return (_base.DOCUMENT,)

elif node.tag == "<!DOCTYPE>":

return (_base.DOCTYPE, node.text,

node.get("publicId"), node.get("systemId"))

elif type(node.tag) == type(ElementTree.Comment):

return _base.COMMENT, node.text

else:

#This is assumed to be an ordinary element

return _base.ELEMENT, node.tag, list(node.attrib.items()), len(node) or node.text

def getFirstChild(self, node):

if isinstance(node, tuple):

element, key, parents, flag = node

else:

element, key, parents, flag = node, None, [], None

if flag in ("text", "tail"):

return None

else:

if element.text:

return element, key, parents, "text"

elif len(element):

parents.append(element)

return element[0], 0, parents, None

else:

return None

def getNextSibling(self, node):

if isinstance(node, tuple):

element, key, parents, flag = node

else:

return None

if flag == "text":

if len(element):

parents.append(element)

return element[0], 0, parents, None

else:

return None

else:

if element.tail and flag != "tail":

return element, key, parents, "tail"

elif key < len(parents[-1]) - 1:

return parents[-1][key+1], key+1, parents, None

else:

return None

def getParentNode(self, node):

if isinstance(node, tuple):

element, key, parents, flag = node

else:

return None

if flag == "text":

if not parents:

return element

else:

return element, key, parents, None

else:

parent = parents.pop()

if not parents:

return parent

else:

return parent, list(parents[-1]).index(parent), parents, None

return locals()