# -----------------------------------------------------------------------------
# Copyright (c) 2012 - 2021, Anaconda, Inc., and Bokeh Contributors.
# All rights reserved.
#
# The full license is in the file LICENSE.txt, distributed with this software.
# -----------------------------------------------------------------------------
""" Thoroughly document Bokeh enumerations

The ``bokeh-enum`` directive generates useful documentation for enumerations,
including all the allowable values. If the number of values is large, the full
list is put in a collapsible code block.

This directive takes the name of a Bokeh enum variable as the argument and the
module name as an option. An optional description may be added as content:

.. code-block:: rest

    .. bokeh-enum:: baz
        :module: bokeh.sphinxext.sample

        Specify a baz style

Examples
--------

The directive above will generate the following output:

    .. bokeh-enum:: baz
        :module: bokeh.sphinxext.sample

        Specify a baz style

Although ``bokeh-enum`` may be used explicitly, it is more often convenient in
conjunction with the :ref:`bokeh.sphinxext.bokeh_autodoc` extension. Together,
the same output above will be generated directly from the following code:

.. code-block:: python

    #: Specify a baz style
    baz = enumeration("a", "b", "c")

"""

# -----------------------------------------------------------------------------
# Boilerplate
# -----------------------------------------------------------------------------
from __future__ import annotations

import logging  # isort:skip

log = logging.getLogger(__name__)

# -----------------------------------------------------------------------------
# Imports
# -----------------------------------------------------------------------------

# Standard library imports
import importlib
import textwrap

# External imports
from docutils.parsers.rst.directives import unchanged
from sphinx.errors import SphinxError

# Bokeh imports
from . import PARALLEL_SAFE
from .bokeh_directive import BokehDirective
from .templates import ENUM_DETAIL

# -----------------------------------------------------------------------------
# Globals and constants
# -----------------------------------------------------------------------------

__all__ = (
    "BokehEnumDirective",
    "setup",
)

# -----------------------------------------------------------------------------
# General API
# -----------------------------------------------------------------------------

# -----------------------------------------------------------------------------
# Dev API
# -----------------------------------------------------------------------------


class BokehEnumDirective(BokehDirective):

    has_content = True
    required_arguments = 1
    option_spec = {
        "module": unchanged,
        "noindex": lambda x: True,  # directives.flag weirdly returns None
    }

    def run(self):
        enum_name = self.arguments[0]
        module_name = self.options["module"]

        try:
            module = importlib.import_module(module_name)
        except ImportError:
            raise SphinxError(f"Could not generate reference docs for {enum_name!r}: could not import module {module_name}")

        enum = getattr(module, enum_name, None)

        fullrepr = repr(enum)
        if len(fullrepr) > 180:
            shortrepr = f"{fullrepr[:40]} .... {fullrepr[-40:]}"
            fullrepr = _wrapper.wrap(fullrepr)
        else:
            shortrepr = fullrepr
            fullrepr = None

        rst_text = ENUM_DETAIL.render(
            name=enum_name,
            module=self.options["module"],
            noindex=self.options.get("noindex", False),
            content=self.content,
            shortrepr=shortrepr,
            fullrepr=fullrepr,
        )

        return self.parse(rst_text, "<bokeh-enum>")


def setup(app):
    """ Required Sphinx extension setup function. """
    app.add_directive_to_domain("py", "bokeh-enum", BokehEnumDirective)

    return PARALLEL_SAFE

# -----------------------------------------------------------------------------
# Private API
# -----------------------------------------------------------------------------

_wrapper = textwrap.TextWrapper(subsequent_indent="    ")

# -----------------------------------------------------------------------------
# Code
# -----------------------------------------------------------------------------