path: root/cad/src/files/ios/printFunc.py

"""
printFunc.py: print method that can be called after populating DOM in order to
see the XML objects in human readable format.

Based on the original files from the pyXML 0.8.4 dom/ext module.

@author: Urmi
@version: $Id$
@copyright: 2004-2008 Nanorex, Inc.  See LICENSE file for details.
"""


from xml.dom import XMLNS_NAMESPACE, XML_NAMESPACE, XHTML_NAMESPACE
import string, re, sys
from xml.dom import Node
from Visitor import Visitor, WalkerInterface

ILLEGAL_LOW_CHARS = '[\x01-\x08\x0B-\x0C\x0E-\x1F]'
ILLEGAL_HIGH_CHARS = '\xEF\xBF[\xBE\xBF]'
XML_ILLEGAL_CHAR_PATTERN = re.compile('%s|%s'%(ILLEGAL_LOW_CHARS, ILLEGAL_HIGH_CHARS))



def PrettyPrint(root, stream=sys.stdout, encoding='UTF-8', indent=' ',
                preserveElements=None):
    """
    Prints the DOM object to stream
    """
    if not hasattr(root, "nodeType"):
        return
    #from xml.dom.ext import Printer
    nss_hints = SeekNss(root)
    preserveElements = preserveElements or []
    owner_doc = root.ownerDocument or root
    if hasattr(owner_doc, 'getElementsByName'):
        #We don't want to insert any whitespace into HTML inline elements
        #preserveElements = preserveElements + HTML_4_TRANSITIONAL_INLINE
        print "No provision for HTML Inline elements"
    visitor = PrintVisitor(stream, encoding, indent,
                           preserveElements, nss_hints)
    PrintWalker(visitor, root).run()
    stream.write('\n')
    return

def SeekNss(node, nss=None):
    """
    traverses the tree to seek an approximate set of defined namespaces
    """
    nss = nss or {}
    for child in node.childNodes:
        if child.nodeType == Node.ELEMENT_NODE:
            if child.namespaceURI:
                nss[child.prefix] = child.namespaceURI
            for attr in child.attributes.values():
                if attr.namespaceURI == XMLNS_NAMESPACE:
                    if attr.localName == 'xmlns':
                        nss[None] = attr.value
                    else:
                        nss[attr.localName] = attr.value
                elif attr.namespaceURI:
                    nss[attr.prefix] = attr.namespaceURI
            SeekNss(child, nss)
    return nss

def utf8_to_code(text, encoding):
    # support for UTF-8 only
    encoding = string.upper(encoding)
    if encoding == 'UTF-8':
        return text

def TranslateCdata(characters, encoding='UTF-8', prev_chars='', markupSafe=0,
                   charsetHandler=utf8_to_code):
    """
    charsetHandler is a function that takes a string or unicode object as the
    first argument, representing the string to be procesed, and an encoding
    specifier as the second argument.  It must return a string or unicode
    object
    """
    if not characters:
        return ''
    new_string = characters
    #Note: use decimal char entity rep because some browsers are broken
    #FIXME: This will bomb for high characters.  Should, for instance, detect
    #The UTF-8 for 0xFFFE and put out 
    if XML_ILLEGAL_CHAR_PATTERN.search(new_string):
        new_string = XML_ILLEGAL_CHAR_PATTERN.subn(
            lambda m: '&#%i;' % ord(m.group()),
            new_string)[0]
    new_string = charsetHandler(new_string, encoding)
    return new_string



def TranslateCdataAttr(characters):
    """
    Handles normalization and some intelligence about quoting
    """
    if not characters:
        return '', "'"
    if "'" in characters:
        delimiter = '"'
        new_chars = re.sub('"', '"', characters)
    else:
        delimiter = "'"
        new_chars = re.sub("'", ''', characters)
    #FIXME: There's more to normalization
    #Convert attribute new-lines to character entity
    # characters is possibly shorter than new_chars (no entities)
    if "\n" in characters:
        new_chars = re.sub('\n', '
', new_chars)
    return new_chars, delimiter


class PrintVisitor(Visitor):
    def __init__(self, stream, encoding, indent='', plainElements=None,
                 nsHints=None, isXhtml=0, force8bit=0):
        self.stream = stream
        self.encoding = encoding
        # Namespaces
        self._namespaces = [{}]
        self._nsHints = nsHints or {}
        # PrettyPrint
        self._indent = indent
        self._depth = 0
        self._inText = 0
        self._plainElements = plainElements or []
        # HTML support
        self._html = None
        self._isXhtml = isXhtml
        self.force8bit = force8bit
        return

    def visit(self, node):
        if self._html is None:
            # Set HTMLDocument flag here for speed
            #print " leave html tag to be None"
            self._html = hasattr(node.ownerDocument, 'getElementsByName')

        nodeType = node.nodeType
        if node.nodeType == Node.ELEMENT_NODE:
            return self.visitElement(node)

        elif node.nodeType == Node.ATTRIBUTE_NODE:
            return self.visitAttr(node)

        elif node.nodeType == Node.TEXT_NODE:
            return self.visitText(node)

        elif node.nodeType == Node.DOCUMENT_NODE:
            return self.visitDocument(node)

        elif node.nodeType == Node.DOCUMENT_TYPE_NODE:
            return self.visitDocumentType(node)


            # It has a node type, but we don't know how to handle it
        raise Exception("Unknown node type: %s" % repr(node))

    def _write(self, text):
        obj = utf8_to_code(text, self.encoding)
        self.stream.write(obj)
        return

    def _tryIndent(self):
        if not self._inText and self._indent:
            self._write('\n' + self._indent*self._depth)
        return

    def visitDocumentType(self, doctype):
        if not doctype.systemId and not doctype.publicId:
            return
        self._tryIndent()
        self._write('<!DOCTYPE %s' % doctype.name)
        if doctype.systemId and '"' in doctype.systemId:
            system = "'%s'" % doctype.systemId
        else:
            system = '"%s"' % doctype.systemId
        if doctype.publicId and '"' in doctype.publicId:
            # We should probably throw an error
            # Valid characters:  <space> | <newline> | <linefeed> |
            #                    [a-zA-Z0-9] | [-'()+,./:=?;!*#@$_%]
            public = "'%s'" % doctype.publicId
        else:
            public = '"%s"' % doctype.publicId
        if doctype.publicId and doctype.systemId:
            self._write(' PUBLIC %s %s' % (public, system))
        elif doctype.systemId:
            self._write(' SYSTEM %s' % system)
        if doctype.entities or doctype.notations:
            print "No support for entities"
        else:
            self._write('>')
        self._inText = 0
        return

    def visitProlog(self):
        self._write("<?xml version='1.0' encoding='%s'?>" % (
            self.encoding or 'utf-8'
        ))
        self._inText = 0
        return

    def visitNodeList(self, node, exclude=None):
        for curr in node:
            curr is not exclude and self.visit(curr)
        return

    def visitDocument(self, node):
        not self._html and self.visitProlog()
        node.doctype and self.visitDocumentType(node.doctype)
        self.visitNodeList(node.childNodes, exclude=node.doctype)
        return

    def visitText(self, node):
        text = node.data
        if self._indent:
            text = string.strip(text) and text
        if text:
            text = TranslateCdata(text, self.encoding)
            self.stream.write(text)
            self._inText = 1
        return

    def visitAttr(self, node):
        if node.namespaceURI == XMLNS_NAMESPACE:
            # Skip namespace declarations
            return
        self._write(' ' + node.name)
        value = node.value
        if value or not self._html:
            text = TranslateCdata(value, self.encoding)
            text, delimiter = TranslateCdataAttr(text)
            self.stream.write("=%s%s%s" % (delimiter, text, delimiter))
        return

    def GetAllNs(self,node):
        #The xml namespace is implicit
        nss = {'xml': XML_NAMESPACE}
        if node.nodeType == Node.ATTRIBUTE_NODE and node.ownerElement:
            return self.GetAllNs(node.ownerElement)
        if node.nodeType == Node.ELEMENT_NODE:
            if node.namespaceURI:
                nss[node.prefix] = node.namespaceURI
            for attr in node.attributes.values():
                if attr.namespaceURI == XMLNS_NAMESPACE:
                    if attr.localName == 'xmlns':
                        nss[None] = attr.value
                    else:
                        nss[attr.localName] = attr.value
                elif attr.namespaceURI:
                    nss[attr.prefix] = attr.namespaceURI
        if node.parentNode:
            #Inner NS/Prefix mappings take precedence over outer ones
            parent_nss = self.GetAllNs(node.parentNode)
            parent_nss.update(nss)
            nss = parent_nss
        return nss

    def visitElement(self, node):
        self._namespaces.append(self._namespaces[-1].copy())
        inline = node.tagName in self._plainElements
        not inline and self._tryIndent()
        self._write('<%s' % node.tagName)
        if self._isXhtml or not self._html:
            namespaces = ''
            if self._isXhtml:
                nss = {'xml': XML_NAMESPACE, None: XHTML_NAMESPACE}
            else:
                nss = self.GetAllNs(node)
            if self._nsHints:
                self._nsHints.update(nss)
                nss = self._nsHints
                self._nsHints = {}
            del nss['xml']
            for prefix in nss.keys():
                if not self._namespaces[-1].has_key(prefix) or self._namespaces[-1][prefix] != nss[prefix]:
                    nsuri, delimiter = TranslateCdataAttr(nss[prefix])
                    if prefix:

                        xmlns = " xmlns:%s=%s%s%s" % (prefix, delimiter,nsuri,delimiter)
                        namespaces = namespaces + xmlns
                    else:

                        xmlns = " xmlns=%s%s%s" % (delimiter,nsuri,delimiter)


                self._namespaces[-1][prefix] = nss[prefix]
            self._write(namespaces)
        for attr in node.attributes.values():
            self.visitAttr(attr)
        if len(node.childNodes):
            self._write('>')
            self._depth = self._depth + 1
            self.visitNodeList(node.childNodes)
            self._depth = self._depth - 1
            if not self._html or (node.tagName not in HTML_FORBIDDEN_END):
                not (self._inText and inline) and self._tryIndent()
                self._write('</%s>' % node.tagName)
        elif not self._html:
            self._write('/>')
        else:
            self._write('>')
        del self._namespaces[-1]
        self._inText = 0
        return


class PrintWalker(WalkerInterface):
    def __init__(self, visitor, startNode):
        WalkerInterface.__init__(self, visitor)
        self.start_node = startNode
        return

    def step(self):
        """
        There is really no step to printing.  It prints the whole thing
        """
        self.visitor.visit(self.start_node)
        return

    def run(self):
        return self.step()