from types import MappingProxyType
from typing import Any, Mapping, Sequence, NamedTuple

from docutils import nodes
from docutils.parsers.rst.directives import class_option
from docutils.parsers.rst.states import Inliner
from sphinx.application import Sphinx
from sphinx.config import Config


class AutoLink(NamedTuple):
    class_name: str
    url_template: str
    title_template: str = "{}"
    options: Mapping[str, Any] = MappingProxyType({"class": class_option})

    def __call__(
        self,
        name: str,
        rawtext: str,
        text: str,
        lineno: int,
        inliner: Inliner,
        options: Mapping[str, Any] = MappingProxyType({}),
        content: Sequence[str] = (),
    ):
        url = self.url_template.format(text)
        title = self.title_template.format(text)
        options = {**dict(classes=[self.class_name]), **options}
        node = nodes.reference(rawtext, title, refuri=url, **options)
        return [node], []


def register_links(app: Sphinx, config: Config):
    gh_url = "https://github.com/{github_user}/{github_repo}".format_map(
        config.html_context
    )
    app.add_role("pr", AutoLink("pr", f"{gh_url}/pull/{{}}", "PR {}"))
    app.add_role("issue", AutoLink("issue", f"{gh_url}/issues/{{}}", "issue {}"))
    app.add_role("noteversion", AutoLink("noteversion", f"{gh_url}/releases/tag/{{}}"))
    # tutorial links
    tutorials_url = "https://anndata-tutorials.readthedocs.io/en/latest/"
    app.add_role(
        "tutorial",
        AutoLink("tutorial", f"{tutorials_url}{{}}.html", "→ tutorial: {}"),
    )


def setup(app: Sphinx):
    app.connect("config-inited", register_links)