"""
    sphinx.domains.changeset
    ~~~~~~~~~~~~~~~~~~~~~~~~

    The changeset domain.

    :copyright: Copyright 2007-2020 by the Sphinx team, see AUTHORS.
    :license: BSD, see LICENSE for details.
"""

from typing import Any, Dict, List, NamedTuple
from typing import cast

from docutils import nodes
from docutils.nodes import Node

from sphinx import addnodes
from sphinx.domains import Domain
from sphinx.locale import _
from sphinx.util.docutils import SphinxDirective


if False:
    # For type annotation
    from sphinx.application import Sphinx
    from sphinx.environment import BuildEnvironment


versionlabels = {
    'versionadded':   _('New in version %s'),
    'versionchanged': _('Changed in version %s'),
    'deprecated':     _('Deprecated since version %s'),
}

versionlabel_classes = {
    'versionadded':     'added',
    'versionchanged':   'changed',
    'deprecated':       'deprecated',
}


class ChangeSet(NamedTuple):
    type: str
    docname: str
    lineno: int
    module: str
    descname: str
    content: str


class VersionChange(SphinxDirective):
    """
    Directive to describe a change/addition/deprecation in a specific version.
    """
    has_content = True
    required_arguments = 1
    optional_arguments = 1
    final_argument_whitespace = True
    option_spec = {}  # type: Dict

    def run(self) -> List[Node]:
        node = addnodes.versionmodified()
        node.document = self.state.document
        self.set_source_info(node)
        node['type'] = self.name
        node['version'] = self.arguments[0]
        text = versionlabels[self.name] % self.arguments[0]
        if len(self.arguments) == 2:
            inodes, messages = self.state.inline_text(self.arguments[1],
                                                      self.lineno + 1)
            para = nodes.paragraph(self.arguments[1], '', *inodes, translatable=False)
            self.set_source_info(para)
            node.append(para)
        else:
            messages = []
        if self.content:
            self.state.nested_parse(self.content, self.content_offset, node)
        classes = ['versionmodified', versionlabel_classes[self.name]]
        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, translatable=False))

            para = cast(nodes.paragraph, node[0])
            para.insert(0, nodes.inline('', '%s: ' % text, classes=classes))
        else:
            para = nodes.paragraph('', '',
                                   nodes.inline('', '%s.' % text,
                                                classes=classes),
                                   translatable=False)
            node.append(para)

        domain = cast(ChangeSetDomain, self.env.get_domain('changeset'))
        domain.note_changeset(node)

        ret = [node]  # type: List[Node]
        ret += messages
        return ret


class ChangeSetDomain(Domain):
    """Domain for changesets."""

    name = 'changeset'
    label = 'changeset'

    initial_data = {
        'changes': {},      # version -> list of ChangeSet
    }  # type: Dict

    @property
    def changesets(self) -> Dict[str, List[ChangeSet]]:
        return self.data.setdefault('changes', {})  # version -> list of ChangeSet

    def note_changeset(self, node: addnodes.versionmodified) -> None:
        version = node['version']
        module = self.env.ref_context.get('py:module')
        objname = self.env.temp_data.get('object')
        changeset = ChangeSet(node['type'], self.env.docname, node.line,
                              module, objname, node.astext())
        self.changesets.setdefault(version, []).append(changeset)

    def clear_doc(self, docname: str) -> None:
        for version, changes in self.changesets.items():
            for changeset in changes[:]:
                if changeset.docname == docname:
                    changes.remove(changeset)

    def merge_domaindata(self, docnames: List[str], otherdata: Dict) -> None:
        # XXX duplicates?
        for version, otherchanges in otherdata['changes'].items():
            changes = self.changesets.setdefault(version, [])
            for changeset in otherchanges:
                if changeset.docname in docnames:
                    changes.append(changeset)

    def process_doc(self, env: "BuildEnvironment", docname: str, document: nodes.document) -> None:  # NOQA
        pass  # nothing to do here. All changesets are registered on calling directive.

    def get_changesets_for(self, version: str) -> List[ChangeSet]:
        return self.changesets.get(version, [])


def setup(app: "Sphinx") -> Dict[str, Any]:
    app.add_domain(ChangeSetDomain)
    app.add_directive('deprecated', VersionChange)
    app.add_directive('versionadded', VersionChange)
    app.add_directive('versionchanged', VersionChange)

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