# -*- coding: utf-8 -*-
"""
    pyspecific.py
    ~~~~~~~~~~~~~

    Sphinx extension with Python doc-specific markup.

    :copyright: 2008-2014 by Georg Brandl.
    :license: Python license.
"""

import re
import io
from os import path
from time import asctime
from pprint import pformat
from docutils.io import StringOutput
from docutils.parsers.rst import Directive
from docutils.utils import new_document

from docutils import nodes, utils

from sphinx import addnodes
from sphinx.builders import Builder
from sphinx.locale import translators
from sphinx.util.nodes import split_explicit_title
from sphinx.writers.html import HTMLTranslator
from sphinx.writers.text import TextWriter
from sphinx.writers.latex import LaTeXTranslator
from sphinx.domains.python import PyModulelevel, PyClassmember

# Support for checking for suspicious markup

import suspicious


ISSUE_URI = 'https://bugs.python.org/issue%s'
SOURCE_URI = 'https://github.com/python/cpython/tree/master/%s'

# monkey-patch reST parser to disable alphabetic and roman enumerated lists
from docutils.parsers.rst.states import Body
Body.enum.converters['loweralpha'] = \
    Body.enum.converters['upperalpha'] = \
    Body.enum.converters['lowerroman'] = \
    Body.enum.converters['upperroman'] = lambda x: None

# monkey-patch HTML and LaTeX translators to keep doctest blocks in the
# doctest docs themselves
orig_visit_literal_block = HTMLTranslator.visit_literal_block
orig_depart_literal_block = LaTeXTranslator.depart_literal_block


def new_visit_literal_block(self, node):
    meta = self.builder.env.metadata[self.builder.current_docname]
    old_trim_doctest_flags = self.highlighter.trim_doctest_flags
    if 'keepdoctest' in meta:
        self.highlighter.trim_doctest_flags = False
    try:
        orig_visit_literal_block(self, node)
    finally:
        self.highlighter.trim_doctest_flags = old_trim_doctest_flags


def new_depart_literal_block(self, node):
    meta = self.builder.env.metadata[self.curfilestack[-1]]
    old_trim_doctest_flags = self.highlighter.trim_doctest_flags
    if 'keepdoctest' in meta:
        self.highlighter.trim_doctest_flags = False
    try:
        orig_depart_literal_block(self, node)
    finally:
        self.highlighter.trim_doctest_flags = old_trim_doctest_flags


HTMLTranslator.visit_literal_block = new_visit_literal_block
LaTeXTranslator.depart_literal_block = new_depart_literal_block


# Support for marking up and linking to bugs.python.org issues

def issue_role(typ, rawtext, text, lineno, inliner, options={}, content=[]):
    issue = utils.unescape(text)
    text = 'bpo-' + issue
    refnode = nodes.reference(text, text, refuri=ISSUE_URI % issue)
    return [refnode], []


# Support for linking to Python source files easily

def source_role(typ, rawtext, text, lineno, inliner, options={}, content=[]):
    has_t, title, target = split_explicit_title(text)
    title = utils.unescape(title)
    target = utils.unescape(target)
    refnode = nodes.reference(title, title, refuri=SOURCE_URI % target)
    return [refnode], []


# Support for marking up implementation details

class ImplementationDetail(Directive):

    has_content = True
    required_arguments = 0
    optional_arguments = 1
    final_argument_whitespace = True

    # This text is copied to templates/dummy.html
    label_text = 'CPython implementation detail:'

    def run(self):
        pnode = nodes.compound(classes=['impl-detail'])
        label = translators['sphinx'].gettext(self.label_text)
        content = self.content
        add_text = nodes.strong(label, label)
        if self.arguments:
            n, m = self.state.inline_text(self.arguments[0], self.lineno)
            pnode.append(nodes.paragraph('', '', *(n + m)))
        self.state.nested_parse(content, self.content_offset, pnode)
        if pnode.children and isinstance(pnode[0], nodes.paragraph):
            content = nodes.inline(pnode[0].rawsource, translatable=True)
            content.source = pnode[0].source
            content.line = pnode[0].line
            content += pnode[0].children
            pnode[0].replace_self(nodes.paragraph('', '', content,
                                                  translatable=False))
            pnode[0].insert(0, add_text)
            pnode[0].insert(1, nodes.Text(' '))
        else:
            pnode.insert(0, nodes.paragraph('', '', add_text))
        return [pnode]


# Support for documenting decorators

class PyDecoratorMixin(object):
    def handle_signature(self, sig, signode):
        ret = super(PyDecoratorMixin, self).handle_signature(sig, signode)
        signode.insert(0, addnodes.desc_addname('@', '@'))
        return ret

    def needs_arglist(self):
        return False


class PyDecoratorFunction(PyDecoratorMixin, PyModulelevel):
    def run(self):
        # a decorator function is a function after all
        self.name = 'py:function'
        return PyModulelevel.run(self)


class PyDecoratorMethod(PyDecoratorMixin, PyClassmember):
    def run(self):
        self.name = 'py:method'
        return PyClassmember.run(self)


class PyCoroutineMixin(object):
    def handle_signature(self, sig, signode):
        ret = super(PyCoroutineMixin, self).handle_signature(sig, signode)
        signode.insert(0, addnodes.desc_annotation('coroutine ', 'coroutine '))
        return ret


class PyCoroutineFunction(PyCoroutineMixin, PyModulelevel):
    def run(self):
        self.name = 'py:function'
        return PyModulelevel.run(self)


class PyCoroutineMethod(PyCoroutineMixin, PyClassmember):
    def run(self):
        self.name = 'py:method'
        return PyClassmember.run(self)


class PyAbstractMethod(PyClassmember):

    def handle_signature(self, sig, signode):
        ret = super(PyAbstractMethod, self).handle_signature(sig, signode)
        signode.insert(0, addnodes.desc_annotation('abstractmethod ',
                                                   'abstractmethod '))
        return ret

    def run(self):
        self.name = 'py:method'
        return PyClassmember.run(self)


# Support for documenting version of removal in deprecations

class DeprecatedRemoved(Directive):
    has_content = True
    required_arguments = 2
    optional_arguments = 1
    final_argument_whitespace = True
    option_spec = {}

    _label = 'Deprecated since version %s, will be removed in version %s'

    def run(self):
        node = addnodes.versionmodified()
        node.document = self.state.document
        node['type'] = 'deprecated-removed'
        version = (self.arguments[0], self.arguments[1])
        node['version'] = version
        text = self._label % version
        if len(self.arguments) == 3:
            inodes, messages = self.state.inline_text(self.arguments[2],
                                                      self.lineno+1)
            para = nodes.paragraph(self.arguments[2], '', *inodes)
            node.append(para)
        else:
            messages = []
        if self.content:
            self.state.nested_parse(self.content, self.content_offset, node)
        if len(node):
            if isinstance(node[0], nodes.paragraph) and node[0].rawsource:
                content = nodes.inline(node[0].rawsource, translatable=True)
                content.source = node[0].source
                content.line = node[0].line
                content += node[0].children
                node[0].replace_self(nodes.paragraph('', '', content))
            node[0].insert(0, nodes.inline('', '%s: ' % text,
                                           classes=['versionmodified']))
        else:
            para = nodes.paragraph('', '',
                                   nodes.inline('', '%s.' % text,
                                                classes=['versionmodified']))
            node.append(para)
        env = self.state.document.settings.env
        env.note_versionchange('deprecated', version[0], node, self.lineno)
        return [node] + messages


# Support for including Misc/NEWS

issue_re = re.compile('(?:[Ii]ssue #|bpo-)([0-9]+)')
whatsnew_re = re.compile(r"(?im)^what's new in (.*?)\??$")


class MiscNews(Directive):
    has_content = False
    required_arguments = 1
    optional_arguments = 0
    final_argument_whitespace = False
    option_spec = {}

    def run(self):
        fname = self.arguments[0]
        source = self.state_machine.input_lines.source(
            self.lineno - self.state_machine.input_offset - 1)
        source_dir = path.dirname(path.abspath(source))
        fpath = path.join(source_dir, fname)
        self.state.document.settings.record_dependencies.add(fpath)
        try:
            with io.open(fpath, encoding='utf-8') as fp:
                content = fp.read()
        except Exception:
            text = 'The NEWS file is not available.'
            node = nodes.strong(text, text)
            return [node]
        content = issue_re.sub(r'`bpo-\1 <https://bugs.python.org/issue\1>`__',
                               content)
        content = whatsnew_re.sub(r'\1', content)
        # remove first 3 lines as they are the main heading
        lines = ['.. default-role:: obj', ''] + content.splitlines()[3:]
        self.state_machine.insert_input(lines, fname)
        return []


# Support for building "topic help" for pydoc

pydoc_topic_labels = [
    'assert', 'assignment', 'atom-identifiers', 'atom-literals',
    'attribute-access', 'attribute-references', 'augassign', 'binary',
    'bitwise', 'bltin-code-objects', 'bltin-ellipsis-object',
    'bltin-null-object', 'bltin-type-objects', 'booleans',
    'break', 'callable-types', 'calls', 'class', 'comparisons', 'compound',
    'context-managers', 'continue', 'conversions', 'customization', 'debugger',
    'del', 'dict', 'dynamic-features', 'else', 'exceptions', 'execmodel',
    'exprlists', 'floating', 'for', 'formatstrings', 'function', 'global',
    'id-classes', 'identifiers', 'if', 'imaginary', 'import', 'in', 'integers',
    'lambda', 'lists', 'naming', 'nonlocal', 'numbers', 'numeric-types',
    'objects', 'operator-summary', 'pass', 'power', 'raise', 'return',
    'sequence-types', 'shifting', 'slicings', 'specialattrs', 'specialnames',
    'string-methods', 'strings', 'subscriptions', 'truth', 'try', 'types',
    'typesfunctions', 'typesmapping', 'typesmethods', 'typesmodules',
    'typesseq', 'typesseq-mutable', 'unary', 'while', 'with', 'yield'
]


class PydocTopicsBuilder(Builder):
    name = 'pydoc-topics'

    def init(self):
        self.topics = {}

    def get_outdated_docs(self):
        return 'all pydoc topics'

    def get_target_uri(self, docname, typ=None):
        return ''  # no URIs

    def write(self, *ignored):
        writer = TextWriter(self)
        for label in self.status_iterator(pydoc_topic_labels,
                                          'building topics... ',
                                          length=len(pydoc_topic_labels)):
            if label not in self.env.domaindata['std']['labels']:
                self.warn('label %r not in documentation' % label)
                continue
            docname, labelid, sectname = self.env.domaindata['std']['labels'][label]
            doctree = self.env.get_and_resolve_doctree(docname, self)
            document = new_document('<section node>')
            document.append(doctree.ids[labelid])
            destination = StringOutput(encoding='utf-8')
            writer.write(document, destination)
            self.topics[label] = writer.output

    def finish(self):
        f = open(path.join(self.outdir, 'topics.py'), 'wb')
        try:
            f.write('# -*- coding: utf-8 -*-\n'.encode('utf-8'))
            f.write(('# Autogenerated by Sphinx on %s\n' % asctime()).encode('utf-8'))
            f.write(('topics = ' + pformat(self.topics) + '\n').encode('utf-8'))
        finally:
            f.close()


# Support for documenting Opcodes

opcode_sig_re = re.compile(r'(\w+(?:\+\d)?)(?:\s*\((.*)\))?')


def parse_opcode_signature(env, sig, signode):
    """Transform an opcode signature into RST nodes."""
    m = opcode_sig_re.match(sig)
    if m is None:
        raise ValueError
    opname, arglist = m.groups()
    signode += addnodes.desc_name(opname, opname)
    if arglist is not None:
        paramlist = addnodes.desc_parameterlist()
        signode += paramlist
        paramlist += addnodes.desc_parameter(arglist, arglist)
    return opname.strip()


# Support for documenting pdb commands

pdbcmd_sig_re = re.compile(r'([a-z()!]+)\s*(.*)')

# later...
# pdbargs_tokens_re = re.compile(r'''[a-zA-Z]+  |  # identifiers
#                                   [.,:]+     |  # punctuation
#                                   [\[\]()]   |  # parens
#                                   \s+           # whitespace
#                                   ''', re.X)


def parse_pdb_command(env, sig, signode):
    """Transform a pdb command signature into RST nodes."""
    m = pdbcmd_sig_re.match(sig)
    if m is None:
        raise ValueError
    name, args = m.groups()
    fullname = name.replace('(', '').replace(')', '')
    signode += addnodes.desc_name(name, name)
    if args:
        signode += addnodes.desc_addname(' '+args, ' '+args)
    return fullname


def setup(app):
    app.add_role('issue', issue_role)
    app.add_role('source', source_role)
    app.add_directive('impl-detail', ImplementationDetail)
    app.add_directive('deprecated-removed', DeprecatedRemoved)
    app.add_builder(PydocTopicsBuilder)
    app.add_builder(suspicious.CheckSuspiciousMarkupBuilder)
    app.add_description_unit('opcode', 'opcode', '%s (opcode)',
                             parse_opcode_signature)
    app.add_description_unit('pdbcommand', 'pdbcmd', '%s (pdb command)',
                             parse_pdb_command)
    app.add_description_unit('2to3fixer', '2to3fixer', '%s (2to3 fixer)')
    app.add_directive_to_domain('py', 'decorator', PyDecoratorFunction)
    app.add_directive_to_domain('py', 'decoratormethod', PyDecoratorMethod)
    app.add_directive_to_domain('py', 'coroutinefunction', PyCoroutineFunction)
    app.add_directive_to_domain('py', 'coroutinemethod', PyCoroutineMethod)
    app.add_directive_to_domain('py', 'abstractmethod', PyAbstractMethod)
    app.add_directive('miscnews', MiscNews)
    return {'version': '1.0', 'parallel_read_safe': True}
