"""
    sphinx.domains.rst
    ~~~~~~~~~~~~~~~~~~

    The reStructuredText domain.

    :copyright: Copyright 2007-2019 by the Sphinx team, see AUTHORS.
    :license: BSD, see LICENSE for details.
"""

import re
from typing import cast

from docutils.parsers.rst import directives

from sphinx import addnodes
from sphinx.directives import ObjectDescription
from sphinx.domains import Domain, ObjType
from sphinx.locale import _, __
from sphinx.roles import XRefRole
from sphinx.util import logging
from sphinx.util.nodes import make_refnode

if False:
    # For type annotation
    from typing import Any, Dict, Iterator, List, Tuple  # NOQA
    from docutils import nodes  # NOQA
    from sphinx.application import Sphinx  # NOQA
    from sphinx.builders import Builder  # NOQA
    from sphinx.environment import BuildEnvironment  # NOQA


logger = logging.getLogger(__name__)

dir_sig_re = re.compile(r'\.\. (.+?)::(.*)$')


class ReSTMarkup(ObjectDescription):
    """
    Description of generic reST markup.
    """

    def add_target_and_index(self, name, sig, signode):
        # type: (str, str, addnodes.desc_signature) -> None
        targetname = self.objtype + '-' + name
        if targetname not in self.state.document.ids:
            signode['names'].append(targetname)
            signode['ids'].append(targetname)
            signode['first'] = (not self.names)
            self.state.document.note_explicit_target(signode)

            domain = cast(ReSTDomain, self.env.get_domain('rst'))
            domain.note_object(self.objtype, name, location=(self.env.docname, self.lineno))

        indextext = self.get_index_text(self.objtype, name)
        if indextext:
            self.indexnode['entries'].append(('single', indextext,
                                              targetname, '', None))

    def get_index_text(self, objectname, name):
        # type: (str, str) -> str
        return ''


def parse_directive(d):
    # type: (str) -> Tuple[str, str]
    """Parse a directive signature.

    Returns (directive, arguments) string tuple.  If no arguments are given,
    returns (directive, '').
    """
    dir = d.strip()
    if not dir.startswith('.'):
        # Assume it is a directive without syntax
        return (dir, '')
    m = dir_sig_re.match(dir)
    if not m:
        return (dir, '')
    parsed_dir, parsed_args = m.groups()
    if parsed_args.strip():
        return (parsed_dir.strip(), ' ' + parsed_args.strip())
    else:
        return (parsed_dir.strip(), '')


class ReSTDirective(ReSTMarkup):
    """
    Description of a reST directive.
    """
    def handle_signature(self, sig, signode):
        # type: (str, addnodes.desc_signature) -> str
        name, args = parse_directive(sig)
        desc_name = '.. %s::' % name
        signode += addnodes.desc_name(desc_name, desc_name)
        if len(args) > 0:
            signode += addnodes.desc_addname(args, args)
        return name

    def get_index_text(self, objectname, name):
        # type: (str, str) -> str
        return _('%s (directive)') % name

    def before_content(self):
        # type: () -> None
        if self.names:
            directives = self.env.ref_context.setdefault('rst:directives', [])
            directives.append(self.names[0])

    def after_content(self):
        # type: () -> None
        directives = self.env.ref_context.setdefault('rst:directives', [])
        if directives:
            directives.pop()


class ReSTDirectiveOption(ReSTMarkup):
    """
    Description of an option for reST directive.
    """
    option_spec = ReSTMarkup.option_spec.copy()
    option_spec.update({
        'type': directives.unchanged,
    })

    def handle_signature(self, sig, signode):
        # type: (str, addnodes.desc_signature) -> str
        try:
            name, argument = re.split(r'\s*:\s+', sig.strip(), 1)
        except ValueError:
            name, argument = sig, None

        signode += addnodes.desc_name(':%s:' % name, ':%s:' % name)
        if argument:
            signode += addnodes.desc_annotation(' ' + argument, ' ' + argument)
        if self.options.get('type'):
            text = ' (%s)' % self.options['type']
            signode += addnodes.desc_annotation(text, text)
        return name

    def add_target_and_index(self, name, sig, signode):
        # type: (str, str, addnodes.desc_signature) -> None
        directive_name = self.current_directive
        targetname = '-'.join([self.objtype, self.current_directive, name])
        if targetname not in self.state.document.ids:
            signode['names'].append(targetname)
            signode['ids'].append(targetname)
            signode['first'] = (not self.names)
            self.state.document.note_explicit_target(signode)

            objname = ':'.join(filter(None, [directive_name, name]))
            domain = cast(ReSTDomain, self.env.get_domain('rst'))
            domain.note_object(self.objtype, objname, location=(self.env.docname, self.lineno))

        if directive_name:
            key = name[0].upper()
            pair = [_('%s (directive)') % directive_name,
                    _(':%s: (directive option)') % name]
            self.indexnode['entries'].append(('pair', '; '.join(pair), targetname, '', key))
        else:
            key = name[0].upper()
            text = _(':%s: (directive option)') % name
            self.indexnode['entries'].append(('single', text, targetname, '', key))

    @property
    def current_directive(self):
        # type: () -> str
        directives = self.env.ref_context.get('rst:directives')
        if directives:
            return directives[-1]
        else:
            return ''


class ReSTRole(ReSTMarkup):
    """
    Description of a reST role.
    """
    def handle_signature(self, sig, signode):
        # type: (str, addnodes.desc_signature) -> str
        signode += addnodes.desc_name(':%s:' % sig, ':%s:' % sig)
        return sig

    def get_index_text(self, objectname, name):
        # type: (str, str) -> str
        return _('%s (role)') % name


class ReSTDomain(Domain):
    """ReStructuredText domain."""
    name = 'rst'
    label = 'reStructuredText'

    object_types = {
        'directive':        ObjType(_('directive'), 'dir'),
        'directive:option': ObjType(_('directive-option'), 'dir'),
        'role':             ObjType(_('role'),      'role'),
    }
    directives = {
        'directive': ReSTDirective,
        'directive:option': ReSTDirectiveOption,
        'role':      ReSTRole,
    }
    roles = {
        'dir':  XRefRole(),
        'role': XRefRole(),
    }
    initial_data = {
        'objects': {},  # fullname -> docname, objtype
    }  # type: Dict[str, Dict[Tuple[str, str], str]]

    @property
    def objects(self):
        # type: () -> Dict[Tuple[str, str], str]
        return self.data.setdefault('objects', {})  # (objtype, fullname) -> docname

    def note_object(self, objtype, name, location=None):
        # type: (str, str, Any) -> None
        if (objtype, name) in self.objects:
            docname = self.objects[objtype, name]
            logger.warning(__('duplicate description of %s %s, other instance in %s') %
                           (objtype, name, docname), location=location)

        self.objects[objtype, name] = self.env.docname

    def clear_doc(self, docname):
        # type: (str) -> None
        for (typ, name), doc in list(self.objects.items()):
            if doc == docname:
                del self.objects[typ, name]

    def merge_domaindata(self, docnames, otherdata):
        # type: (List[str], Dict) -> None
        # XXX check duplicates
        for (typ, name), doc in otherdata['objects'].items():
            if doc in docnames:
                self.objects[typ, name] = doc

    def resolve_xref(self, env, fromdocname, builder, typ, target, node, contnode):
        # type: (BuildEnvironment, str, Builder, str, str, addnodes.pending_xref, nodes.Element) -> nodes.Element  # NOQA
        objtypes = self.objtypes_for_role(typ)
        for objtype in objtypes:
            todocname = self.objects.get((objtype, target))
            if todocname:
                return make_refnode(builder, fromdocname, todocname,
                                    objtype + '-' + target,
                                    contnode, target + ' ' + objtype)
        return None

    def resolve_any_xref(self, env, fromdocname, builder, target, node, contnode):
        # type: (BuildEnvironment, str, Builder, str, addnodes.pending_xref, nodes.Element) -> List[Tuple[str, nodes.Element]]  # NOQA
        results = []  # type: List[Tuple[str, nodes.Element]]
        for objtype in self.object_types:
            todocname = self.objects.get((objtype, target))
            if todocname:
                results.append(('rst:' + self.role_for_objtype(objtype),
                                make_refnode(builder, fromdocname, todocname,
                                             objtype + '-' + target,
                                             contnode, target + ' ' + objtype)))
        return results

    def get_objects(self):
        # type: () -> Iterator[Tuple[str, str, str, str, str, int]]
        for (typ, name), docname in self.data['objects'].items():
            yield name, name, typ, docname, typ + '-' + name, 1


def setup(app):
    # type: (Sphinx) -> Dict[str, Any]
    app.add_domain(ReSTDomain)

    return {
        'version': 'builtin',
        'env_version': 1,
        'parallel_read_safe': True,
        'parallel_write_safe': True,
    }
