# -*- coding: utf-8 -*-
"""
    sphinx.util.nodes
    ~~~~~~~~~~~~~~~~~

    Docutils node-related utility functions for Sphinx.

    :copyright: Copyright 2007-2015 by the Sphinx team, see AUTHORS.
    :license: BSD, see LICENSE for details.
"""

import re

from six import text_type
from docutils import nodes

from sphinx import addnodes
from sphinx.locale import pairindextypes


class WarningStream(object):

    def __init__(self, warnfunc):
        self.warnfunc = warnfunc
        self._re = re.compile(r'\((DEBUG|INFO|WARNING|ERROR|SEVERE)/[0-4]\)')

    def write(self, text):
        text = text.strip()
        if text:
            self.warnfunc(self._re.sub(r'\1:', text), None, '')


# \x00 means the "<" was backslash-escaped
explicit_title_re = re.compile(r'^(.+?)\s*(?<!\x00)<(.*?)>$', re.DOTALL)
caption_ref_re = explicit_title_re  # b/w compat alias


def apply_source_workaround(node):
    if node.source and node.rawsource:
        return

    # workaround: nodes.term doesn't have source, line and rawsource
    # (fixed in Docutils r7495)
    if isinstance(node, nodes.term):
        definition_list_item = node.parent
        if definition_list_item.line is not None:
            node.source = definition_list_item.source
            node.line = definition_list_item.line - 1
            node.rawsource = definition_list_item. \
                rawsource.split("\n", 2)[0]
            return

    # workaround: docutils-0.10.0 or older's nodes.caption for nodes.figure
    # and nodes.title for nodes.admonition doesn't have source, line.
    # this issue was filed to Docutils tracker:
    # sf.net/tracker/?func=detail&aid=3599485&group_id=38414&atid=422032
    # sourceforge.net/p/docutils/patches/108/
    if (isinstance(node, (
            nodes.caption,
            nodes.title,
            nodes.rubric,
            nodes.line,
    ))):
        node.source = find_source_node(node)
        node.line = 0  # need fix docutils to get `node.line`
        return


IGNORED_NODES = (
    nodes.Invisible,
    nodes.Inline,
    nodes.literal_block,
    nodes.doctest_block,
    # XXX there are probably more
)


def is_translatable(node):
    if isinstance(node, nodes.TextElement):
        apply_source_workaround(node)

        if not node.source:
            return False  # built-in message
        if isinstance(node, IGNORED_NODES) and 'translatable' not in node:
            return False
        # <field_name>orphan</field_name>
        # XXX ignore all metadata (== docinfo)
        if isinstance(node, nodes.field_name) and node.children[0] == 'orphan':
            return False
        return True

    if isinstance(node, nodes.image) and node.get('translatable'):
        return True

    return False


LITERAL_TYPE_NODES = (
    nodes.literal_block,
    nodes.doctest_block,
    nodes.raw,
)
IMAGE_TYPE_NODES = (
    nodes.image,
)


def extract_messages(doctree):
    """Extract translatable messages from a document tree."""
    for node in doctree.traverse(is_translatable):
        if isinstance(node, LITERAL_TYPE_NODES):
            msg = node.rawsource
            if not msg:
                msg = node.astext()
        elif isinstance(node, IMAGE_TYPE_NODES):
            msg = '.. image:: %s' % node['uri']
            if node.get('alt'):
                msg += '\n   :alt: %s' % node['alt']
        else:
            msg = node.rawsource.replace('\n', ' ').strip()

        # XXX nodes rendering empty are likely a bug in sphinx.addnodes
        if msg:
            yield node, msg


def find_source_node(node):
    for pnode in traverse_parent(node):
        if pnode.source:
            return pnode.source


def traverse_parent(node):
    while node:
        yield node
        node = node.parent


def traverse_translatable_index(doctree):
    """Traverse translatable index node from a document tree."""
    def is_block_index(node):
        return isinstance(node, addnodes.index) and  \
            node.get('inline') is False
    for node in doctree.traverse(is_block_index):
        if 'raw_entries' in node:
            entries = node['raw_entries']
        else:
            entries = node['entries']
        yield node, entries


def nested_parse_with_titles(state, content, node):
    """Version of state.nested_parse() that allows titles and does not require
    titles to have the same decoration as the calling document.

    This is useful when the parsed content comes from a completely different
    context, such as docstrings.
    """
    # hack around title style bookkeeping
    surrounding_title_styles = state.memo.title_styles
    surrounding_section_level = state.memo.section_level
    state.memo.title_styles = []
    state.memo.section_level = 0
    try:
        return state.nested_parse(content, 0, node, match_titles=1)
    finally:
        state.memo.title_styles = surrounding_title_styles
        state.memo.section_level = surrounding_section_level


def clean_astext(node):
    """Like node.astext(), but ignore images."""
    node = node.deepcopy()
    for img in node.traverse(nodes.image):
        img['alt'] = ''
    return node.astext()


def split_explicit_title(text):
    """Split role content into title and target, if given."""
    match = explicit_title_re.match(text)
    if match:
        return True, match.group(1), match.group(2)
    return False, text, text


indextypes = [
    'single', 'pair', 'double', 'triple', 'see', 'seealso',
]


def process_index_entry(entry, targetid):
    indexentries = []
    entry = entry.strip()
    oentry = entry
    main = ''
    if entry.startswith('!'):
        main = 'main'
        entry = entry[1:].lstrip()
    for type in pairindextypes:
        if entry.startswith(type+':'):
            value = entry[len(type)+1:].strip()
            value = pairindextypes[type] + '; ' + value
            indexentries.append(('pair', value, targetid, main))
            break
    else:
        for type in indextypes:
            if entry.startswith(type+':'):
                value = entry[len(type)+1:].strip()
                if type == 'double':
                    type = 'pair'
                indexentries.append((type, value, targetid, main))
                break
        # shorthand notation for single entries
        else:
            for value in oentry.split(','):
                value = value.strip()
                main = ''
                if value.startswith('!'):
                    main = 'main'
                    value = value[1:].lstrip()
                if not value:
                    continue
                indexentries.append(('single', value, targetid, main))
    return indexentries


def inline_all_toctrees(builder, docnameset, docname, tree, colorfunc):
    """Inline all toctrees in the *tree*.

    Record all docnames in *docnameset*, and output docnames with *colorfunc*.
    """
    tree = tree.deepcopy()
    for toctreenode in tree.traverse(addnodes.toctree):
        newnodes = []
        includefiles = map(text_type, toctreenode['includefiles'])
        for includefile in includefiles:
            try:
                builder.info(colorfunc(includefile) + " ", nonl=1)
                subtree = inline_all_toctrees(builder, docnameset, includefile,
                                              builder.env.get_doctree(includefile),
                                              colorfunc)
                docnameset.add(includefile)
            except Exception:
                builder.warn('toctree contains ref to nonexisting '
                             'file %r' % includefile,
                             builder.env.doc2path(docname))
            else:
                sof = addnodes.start_of_file(docname=includefile)
                sof.children = subtree.children
                for sectionnode in sof.traverse(nodes.section):
                    if 'docname' not in sectionnode:
                        sectionnode['docname'] = includefile
                newnodes.append(sof)
        toctreenode.parent.replace(toctreenode, newnodes)
    return tree


def make_refnode(builder, fromdocname, todocname, targetid, child, title=None):
    """Shortcut to create a reference node."""
    node = nodes.reference('', '', internal=True)
    if fromdocname == todocname:
        node['refid'] = targetid
    else:
        node['refuri'] = (builder.get_relative_uri(fromdocname, todocname) +
                          '#' + targetid)
    if title:
        node['reftitle'] = title
    node.append(child)
    return node


def set_source_info(directive, node):
    node.source, node.line = \
        directive.state_machine.get_source_and_line(directive.lineno)


def set_role_source_info(inliner, lineno, node):
    node.source, node.line = inliner.reporter.get_source_and_line(lineno)


# monkey-patch Element.copy to copy the rawsource

def _new_copy(self):
    return self.__class__(self.rawsource, **self.attributes)

nodes.Element.copy = _new_copy
