# Configuration file for the Sphinx documentation builder.
# https://www.sphinx-doc.org/en/master/usage/configuration.html

import ast
import importlib
import inspect
import sys
import typing
from pathlib import Path

import git
import tomli
from sphinx.application import Sphinx

# -- Project information -----------------------------------------------------

project = "Bot Core"
copyright = "2021, Python Discord"
author = "Python Discord"

PROJECT_ROOT = Path(__file__).parent.parent
REPO_LINK = "https://github.com/python-discord/bot-core"
SOURCE_FILE_LINK = f"{REPO_LINK}/blob/{git.Repo(PROJECT_ROOT).commit().hexsha}"

sys.path.insert(0, str(PROJECT_ROOT.absolute()))

# The full version, including alpha/beta/rc tags
release = version = tomli.loads(
    (PROJECT_ROOT / "pyproject.toml").read_text(encoding="utf-8")
)["tool"]["poetry"]["version"]

# -- General configuration ---------------------------------------------------

add_module_names = False

# Add any Sphinx extension module names here, as strings. They can be
# extensions coming with Sphinx (named "sphinx.ext.*") or your custom
# ones.
extensions = [
    "sphinx.ext.extlinks",
    "sphinx.ext.intersphinx",
    "sphinx.ext.autodoc",
    "sphinx.ext.todo",
    "sphinx.ext.napoleon",
    "sphinx_autodoc_typehints",
    "releases",
    "sphinx.ext.linkcode",
    "sphinx.ext.githubpages",
]

# Add any paths that contain templates here, relative to this directory.
templates_path = ["_templates"]

# List of patterns, relative to source directory, that match files and
# directories to ignore when looking for source files.
# This pattern also affects html_static_path and html_extra_path.
exclude_patterns = []


# -- Options for HTML output -------------------------------------------------

# The theme to use for HTML and HTML Help pages.  See the documentation for
# a list of builtin themes.
#
html_theme = "furo"

html_theme_options = {
    "light_css_variables": {
        "color-api-name": "var(--color-link)",
    },
}

# Add any paths that contain custom static files (such as style sheets) here,
# relative to this directory. They are copied after the builtin static files,
# so a file named "default.css" will overwrite the builtin "default.css".
html_static_path = ["_static"]
html_title = f"{project} v{version}"
html_short_title = project

html_logo = "https://raw.githubusercontent.com/python-discord/branding/main/logos/logo_full/logo_full.min.svg"
html_favicon = html_logo

html_css_files = [
    "changelog.css",
    "logo.css",
]

html_js_files = [
    "changelog.js",
]


# -- Autodoc cleanup ---------------------------------------------------------
# Clean up the output generated by autodoc to produce a nicer documentation tree
# This is kept in a function to avoid polluting the namespace
def __cleanup() -> None:
    for file in (PROJECT_ROOT / "docs" / "output").iterdir():
        if file.name == "modules.rst":
            # We only have one module, so this is redundant
            # Remove it and flatten out the tree
            file.unlink()
            continue

        elif file.name in ("botcore.rst", "botcore.exts.rst"):
            content = file.read_text(encoding="utf-8").splitlines(keepends=True)

            # Rename the extension to be less wordy
            # Example: botcore.exts -> Botcore Exts
            title = content[0].split()[0].strip().replace("botcore.", "").replace(".", " ").title()
            title = f"{title}\n{'=' * len(title)}\n\n"
            content[0:2] = title

            file.write_text("".join(content), encoding="utf-8")

        else:
            # Clean up the submodule name so it's just the name without the top level module name
            # example: `botcore.regex module` -> `regex`
            lines = file.read_text(encoding="utf-8").splitlines(keepends=True)
            lines[0] = lines[0].replace("module", "").strip().split(".")[-1] + "\n"
            file.write_text("".join(lines))

        # Take the opportunity to configure autodoc
        content = file.read_text(encoding="utf-8").replace("undoc-members", "special-members")
        file.write_text(content, encoding="utf-8")


__cleanup()


def skip(*args) -> bool:
    """Things that should be skipped by the autodoc generation."""
    name = args[2]
    would_skip = args[4]

    if name in (
        "__weakref__",
    ):
        return True
    return would_skip


def setup(app: Sphinx) -> None:
    """Add extra hook-based autodoc configuration."""
    app.connect("autodoc-skip-member", skip)


# -- Extension configuration -------------------------------------------------

# -- Options for todo extension ----------------------------------------------

# If true, `todo` and `todoList` produce output, else they produce nothing.
todo_include_todos = True


# -- Options for napoleon extension ------------------------------------------
napoleon_google_docstring = True
napoleon_numpy_docstring = False
napoleon_attr_annotations = True


# -- Options for releases extension ------------------------------------------
releases_github_path = REPO_LINK.removeprefix("https://github.com/")


# -- Options for extlinks extension ------------------------------------------
extlinks = {
    "repo-file": (f"{REPO_LINK}/blob/main/%s", "repo-file %s")
}


# -- Options for intersphinx extension ---------------------------------------
intersphinx_mapping = {
    "python": ("https://docs.python.org/3", None),
    "discord": ("https://discordpy.readthedocs.io/en/master/", None),
}


# -- Options for the linkcode extension --------------------------------------
def linkcode_resolve(domain: str, info: dict[str, str]) -> typing.Optional[str]:
    """
    Function called by linkcode to get the URL for a given resource.

    See for more details:
    https://www.sphinx-doc.org/en/master/usage/extensions/linkcode.html#confval-linkcode_resolve
    """
    if domain != "py":
        raise Exception("Unknown domain passed to linkcode function.")

    symbol_name = info["fullname"]

    module = importlib.import_module(info["module"])

    symbol = [module]
    for name in symbol_name.split("."):
        symbol.append(getattr(symbol[-1], name))
        symbol_name = name

    try:
        lines, start = inspect.getsourcelines(symbol[-1])
        end = start + len(lines)
    except TypeError:
        # Find variables by parsing the ast
        source = ast.parse(inspect.getsource(symbol[-2]))
        while isinstance(source.body[0], ast.ClassDef):
            source = source.body[0]

        for ast_obj in source.body:
            if isinstance(ast_obj, ast.Assign):
                names = []
                for target in ast_obj.targets:
                    if isinstance(target, ast.Tuple):
                        names.extend([name.id for name in target.elts])
                    else:
                        names.append(target.id)

                if symbol_name in names:
                    start, end = ast_obj.lineno, ast_obj.end_lineno
                    break
        else:
            raise Exception(f"Could not find symbol `{symbol_name}` in {module.__name__}.")

        _, offset = inspect.getsourcelines(symbol[-2])
        if offset != 0:
            offset -= 1
        start += offset
        end += offset

    file = Path(inspect.getfile(module)).relative_to(PROJECT_ROOT).as_posix()

    url = f"{SOURCE_FILE_LINK}/{file}#L{start}"
    if end != start:
        url += f"-L{end}"

    return url