#!/usr/bin/env python3
# -*- coding: utf-8 -*-
#
# LightGBM documentation build configuration file, created by
# sphinx-quickstart on Thu May  4 14:30:58 2017.
#
# This file is execfile()d with the current directory set to its
# containing dir.
#
# Note that not all possible configuration values are present in this
# autogenerated file.
#
# All configuration values have a default; values that are commented out
# serve to show the default.

# If extensions (or modules to document with autodoc) are in another directory,
# add these directories to sys.path here. If the directory is relative to the
# documentation root, use os.path.abspath to make it absolute.
"""Sphinx configuration file."""
import datetime
import os
import sys
import sphinx

from distutils.dir_util import copy_tree
from docutils.parsers.rst import Directive
from sphinx.errors import VersionRequirementError
from subprocess import PIPE, Popen

CURR_PATH = os.path.abspath(os.path.dirname(__file__))
LIB_PATH = os.path.join(CURR_PATH, os.path.pardir, 'python-package')
sys.path.insert(0, LIB_PATH)

# -- mock out modules
try:
    from unittest.mock import Mock  # Python 3.x
except ImportError:
    from mock import Mock  # Python 2.x

MOCK_MODULES = ['numpy', 'scipy', 'scipy.sparse',
                'sklearn', 'matplotlib', 'pandas', 'graphviz']
for mod_name in MOCK_MODULES:
    sys.modules[mod_name] = Mock()


class IgnoredDirective(Directive):
    """Stub for unknown directives."""

    has_content = True

    def run(self):
        """Do nothing."""
        return []


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

os.environ['LIGHTGBM_BUILD_DOC'] = '1'
C_API = os.environ.get('C_API', '').lower().strip() != 'no'
RTD = bool(os.environ.get('READTHEDOCS', ''))

# If your documentation needs a minimal Sphinx version, state it here.
needs_sphinx = '1.3'  # Due to sphinx.ext.napoleon
if needs_sphinx > sphinx.__version__:
    message = 'This project needs at least Sphinx v%s' % needs_sphinx
    raise VersionRequirementError(message)

# 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.autodoc',
    'sphinx.ext.autosummary',
    'sphinx.ext.todo',
    'sphinx.ext.viewcode',
    'sphinx.ext.napoleon',
]

autodoc_default_flags = ['members', 'inherited-members', 'show-inheritance']
autodoc_default_options = {
    "members": True,
    "inherited-members": True,
    "show-inheritance": True,
}

# Generate autosummary pages. Output should be set with: `:toctree: pythonapi/`
autosummary_generate = ['Python-API.rst']

# Only the class' docstring is inserted.
autoclass_content = 'class'

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

# The master toctree document.
master_doc = 'index'

# General information about the project.
project = 'LightGBM'
copyright = '%s, Microsoft Corporation' % str(datetime.datetime.now().year)
author = 'Microsoft Corporation'

# The version info for the project you're documenting, acts as replacement for
# |version| and |release|, also used in various other places throughout the
# built documents.
with open(os.path.join(CURR_PATH, os.path.pardir, 'VERSION.txt'), 'r') as f:
    # The short X.Y version.
    version = f.read().strip()

    # The full version, including alpha/beta/rc tags.
    release = version

# The language for content autogenerated by Sphinx. Refer to documentation
# for a list of supported languages.
#
# This is also used if you do content translation via gettext catalogs.
# Usually you set "language" from the command line for these cases.
language = None

# List of patterns, relative to source directory, that match files and
# directories to ignore when looking for source files.
# This patterns also effect to html_static_path and html_extra_path
exclude_patterns = ['_build', 'Thumbs.db', '.DS_Store']

# The name of the Pygments (syntax highlighting) style to use.
pygments_style = 'default'

# -- Configuration for C API docs generation ------------------------------

if C_API:
    extensions.extend([
        'breathe',
    ])
    breathe_projects = {
        "LightGBM": os.path.join(CURR_PATH, 'doxyoutput', 'xml')
    }
    breathe_default_project = "LightGBM"
    breathe_domain_by_extension = {
        "h": "c",
    }
    breathe_show_define_initializer = True

# -- 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 = 'sphinx_rtd_theme'

# Theme options are theme-specific and customize the look and feel of a theme
# further.  For a list of options available for each theme, see the
# documentation.
html_theme_options = {
    'includehidden': False,
}

# 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']

# -- Options for HTMLHelp output ------------------------------------------

# Output file base name for HTML help builder.
htmlhelp_basename = 'LightGBMdoc'


def generate_doxygen_xml(app):
    """Generate XML documentation for C API by Doxygen.

    Parameters
    ----------
    app : object
        The application object representing the Sphinx process.
    """
    doxygen_args = [
        "INPUT={}".format(os.path.join(CURR_PATH, os.path.pardir,
                                       'include', 'LightGBM', 'c_api.h')),
        "OUTPUT_DIRECTORY={}".format(os.path.join(CURR_PATH, 'doxyoutput')),
        "GENERATE_HTML=NO",
        "GENERATE_LATEX=NO",
        "GENERATE_XML=YES",
        "XML_OUTPUT=xml",
        "XML_PROGRAMLISTING=YES",
        r'ALIASES="rst=\verbatim embed:rst:leading-asterisk"',
        r'ALIASES+="endrst=\endverbatim"',
        "ENABLE_PREPROCESSING=YES",
        "MACRO_EXPANSION=YES",
        "EXPAND_ONLY_PREDEF=NO",
        "SKIP_FUNCTION_MACROS=NO",
        "SORT_BRIEF_DOCS=YES",
        "WARN_AS_ERROR=YES",
    ]
    doxygen_input = '\n'.join(doxygen_args)
    is_py3 = sys.version[0] == "3"
    if is_py3:
        doxygen_input = bytes(doxygen_input, "utf-8")
    if not os.path.exists(os.path.join(CURR_PATH, 'doxyoutput')):
        os.makedirs(os.path.join(CURR_PATH, 'doxyoutput'))
    try:
        # Warning! The following code can cause buffer overflows on RTD.
        # Consider suppressing output completely if RTD project silently fails.
        # Refer to https://github.com/svenevs/exhale
        # /blob/fe7644829057af622e467bb529db6c03a830da99/exhale/deploy.py#L99-L111
        process = Popen(["doxygen", "-"],
                        stdin=PIPE, stdout=PIPE, stderr=PIPE)
        stdout, stderr = process.communicate(doxygen_input)
        output = '\n'.join([i.decode('utf-8') if is_py3 else i
                            for i in (stdout, stderr) if i is not None])
        if process.returncode != 0:
            raise RuntimeError(output)
        else:
            print(output)
    except BaseException as e:
        raise Exception("An error has occurred while executing Doxygen\n" + str(e))


def generate_r_docs(app):
    """Generate documentation for R-package.

    Parameters
    ----------
    app : object
        The application object representing the Sphinx process.
    """
    commands = """
    echo 'options(repos = "https://cran.rstudio.com")' > $HOME/.Rprofile
    /home/docs/.conda/bin/conda create -q -y -n r_env \
        r-base=3.5.1=h1e0a451_2 \
        r-devtools=1.13.6=r351h6115d3f_0 \
        r-data.table=1.11.4=r351h96ca727_0 \
        r-jsonlite=1.5=r351h96ca727_0 \
        r-matrix=1.2_14=r351h96ca727_0 \
        r-testthat=2.0.0=r351h29659fb_0 \
        cmake=3.14.0=h52cb24c_0 \
        ca-certificates=2019.11.27=0
    /home/docs/.conda/bin/conda install -q -y -n r_env -c conda-forge \
        r-pkgdown=1.3.0=r35h6115d3f_1001 \
        r-roxygen2=6.1.1=r35h0357c0b_1001
    source /home/docs/.conda/bin/activate r_env
    export TAR=/bin/tar
    cd {0}
    sed -i'.bak' '/# Build the package (do not touch this line!)/q' build_r.R
    Rscript build_r.R
    Rscript build_r_site.R
    """.format(os.path.join(CURR_PATH, os.path.pardir))
    try:
        # Warning! The following code can cause buffer overflows on RTD.
        # Consider suppressing output completely if RTD project silently fails.
        # Refer to https://github.com/svenevs/exhale
        # /blob/fe7644829057af622e467bb529db6c03a830da99/exhale/deploy.py#L99-L111
        process = Popen(['/bin/bash'],
                        stdin=PIPE, stdout=PIPE, stderr=PIPE,
                        universal_newlines=True)
        stdout, stderr = process.communicate(commands)
        output = '\n'.join([i for i in (stdout, stderr) if i is not None])
        if process.returncode != 0:
            raise RuntimeError(output)
        else:
            print(output)
    except BaseException as e:
        raise Exception("An error has occurred while generating documentation for R-package\n" + str(e))


def setup(app):
    """Add new elements at Sphinx initialization time.

    Parameters
    ----------
    app : object
        The application object representing the Sphinx process.
    """
    first_run = not os.path.exists(os.path.join(CURR_PATH, '_FIRST_RUN.flag'))
    if first_run and RTD:
        open(os.path.join(CURR_PATH, '_FIRST_RUN.flag'), 'w').close()
    if C_API:
        app.connect("builder-inited", generate_doxygen_xml)
    else:
        app.add_directive('doxygenfile', IgnoredDirective)
    if RTD:  # build R docs only on Read the Docs site
        if first_run:
            app.connect("builder-inited", generate_r_docs)
        app.connect("build-finished",
                    lambda app, exception: copy_tree(os.path.join(CURR_PATH, os.path.pardir, "lightgbm_r", "docs"),
                                                     os.path.join(app.outdir, "R"), verbose=0))
    add_js_file = getattr(app, 'add_js_file', False) or app.add_javascript
    add_js_file("js/script.js")
