import datetime
import os
import yaml

############################
# LXD custom initializations #
############################

import sys
import subprocess
from git import Repo
import filecmp
import ast
import re
import shutil

sys.path.insert(0, os.path.abspath('.'))
from redirects import redirects  # noqa: F401 (used by sphinx_reredirects via conf.py namespace)

sys.path.append('.sphinx/')

# Set global version variable used in objects.inv to numeric version defined in flex.go
with open("../shared/version/flex.go") as fd:
    match = re.search(r'var Version = "([^"]+)"', fd.read())
    version = match.group(1) if match else "unknown"


#######################
# Project information #
#######################

# Project name
project = 'LXD'
author = 'LXD contributors'

# Sidebar documentation title; best kept reasonably short
# To disable the title, set to an empty string.
html_title = project + ' documentation ' + version

# Copyright string; shown at the bottom of the page
copyright = '2014-%s AGPL-3.0, %s' % (datetime.date.today().year, author)

# Documentation website URL

# Use RTD canonical URL to ensure duplicate pages have a single canonical URL
# that includes the version (such as /latest/); helps SEO.
# See: https://docs.readthedocs.com/platform/stable/canonical-urls.html and
# https://www.sphinx-doc.org/en/master/usage/configuration.html#confval-html_baseurl
# Second argument is for local builds where READTHEDOCS_CANONICAL_URL is not available
html_baseurl = os.environ.get('READTHEDOCS_CANONICAL_URL', '/')

# NOTE: The Open Graph Protocol (OGP) enhances page display in a social graph
#       and is used by social media platforms; see https://ogp.me/
ogp_site_url = html_baseurl

# Preview name of the documentation website
ogp_site_name = html_title

# Preview image URL
ogp_image = 'https://documentation.ubuntu.com/lxd/latest/_static/lxd_tag.png'

# Product favicon; shown in bookmarks, browser tabs, etc.
html_favicon = '_static/favicon.ico'

# Dictionary of values to pass into the Sphinx context for all pages:
# https://www.sphinx-doc.org/en/master/usage/configuration.html#confval-html_context
html_context = {
    # Product page URL; can be different from product docs URL
    'product_page': 'canonical.com/lxd',

    # Product tag image; the orange part of your logo, shown in the page header
    'product_tag': '_static/lxd_tag.png',

    # Your Discourse instance URL
    # NOTE: If set, adding ':discourse: 123' to an .rst file
    #       will add a link to Discourse topic 123 at the bottom of the page.
    'discourse': 'https://discourse.ubuntu.com/c/lxd/',

    # LXD docs refer to two different Discourse instances
    'discourse_prefix': {
        'ubuntu': 'https://discourse.ubuntu.com/t/',
        'lxc': 'https://discuss.linuxcontainers.org/t/'
    },

    # Your Mattermost channel URL
    'mattermost': '',

    # Your Matrix channel URL
    'matrix': 'https://matrix.to/#/#documentation:ubuntu.com',

    # Your documentation GitHub repository URL
    # NOTE: If set, links for viewing the documentation source files
    #       and creating GitHub issues are added at the bottom of each page.
    'github_url': 'https://github.com/canonical/lxd',

    # Docs branch in the repo; used in links for viewing the source files
    'repo_default_branch': 'main',

    # Docs location in the repo; used in links for viewing the source files
    'repo_folder': '/doc/',

    # Enables the Previous / Next buttons at the bottom of pages
    # NOTE: Valid options are none, prev, next, both
    'sequential_nav': 'both',

    # Enables listing contributors on individual pages
    # This feature is deprecated and will be removed in the future
    'display_contributors': False,

    # Required for feedback button
    'github_issues': 'enabled',
}

html_extra_path = ['_extra']

# Enables the pencil icon to edit pages on GitHub, shown at the top of each page
html_theme_options = {
    'source_edit_link': html_context['github_url']
}

# Project slug
# Required if your project is hosted on documentation.ubuntu.com
slug = 'lxd'

#######################
# Sitemap configuration: https://sphinx-sitemap.readthedocs.io/
#######################

# sphinx-sitemap uses html_baseurl (set earlier in this file) to generate the full URL for each page:

sitemap_url_scheme = '{link}'

# Include `lastmod` dates in the sitemap:
sitemap_show_lastmod = True

# Exclude generated pages from the sitemap:
sitemap_excludes = [
    '404/',
    'genindex/',
    'search/',
]

# TODO: Add more pages to sitemap_excludes if needed. Wildcards are supported.
#       For example, to exclude module pages generated by autodoc, add '_modules/*'.

#######################
# Template and asset locations
#######################

html_static_path = ['_static']
templates_path = ['_templates']


#############
# Redirects #
#############

# To set up redirects in the Read the Docs project dashboard:
# https://docs.readthedocs.io/en/stable/guides/redirects.html

# redirects = {}
# NOTE: The above line is commented out because LXD imports redirects from redirects.py
# instead of setting it here


###########################
# Link checker exceptions #
###########################

# A regex list of URLs that are ignored by 'make linkcheck'

# Always ignore these links
linkcheck_ignore = [
    r"https?://localhost.*",
    r"https?://127\.0\.0\.1.*",
    r"^/.*/api/",
    # These links often/always fail both locally and in GitHub CI
    r"https://ceph\.io.*",
    r"https://.*\.sourceforge\.net.*",
    r"https://www\.gnu\.org.*",
    # These links often fail due to infra issues
    r"https://.*\.canonical\.com.*",
    r"https://snapcraft\.io.*",
    r"https://ubuntu\.com.*",
    r"https://.*\.launchpad\.net.*",
    # Ignore so that we can refer to an unpublished release when preparing release notes
    r"https://github\.com/canonical/lxd/compare.*",
    r"https://github\.com/canonical/lxd/releases/tag/lxd-.*",
    r'https://kubernetes\.io/.*',
]

# Ignore these links in GitHub CI due to site restrictions causing failures
# In local checks, they are not ignored and should pass
if os.environ.get('CI') == 'true':
    linkcheck_ignore.extend([
        r"https://www\.hpe\.com.*",
        r"https://www\.schlachter\.tech.*",
        r"https://www\.dell\.com.*",
    ])

# Pages on which to ignore anchors
# (This list will be appended to linkcheck_anchors_ignore_for_url)
linkcheck_anchors_ignore_for_url = [
    r'https://github\.com/.*',
    r'https://snapcraft\.io/docs/.*',
    'https://docs.docker.com/network/packet-filtering-firewalls/'
]

linkcheck_exclude_documents = [r'.*/manpages/.*']

# Increase linkcheck rate limit timeout max; default when unset is 300
# https://www.sphinx-doc.org/en/master/usage/configuration.html#confval-linkcheck_timeout
linkcheck_rate_limit_timeout = 600

# Increase linkcheck retries; default when unset is 1
# https://www.sphinx-doc.org/en/master/usage/configuration.html#confval-linkcheck_retries
linkcheck_retries = 3

########################
# Configuration extras #
########################

extensions = [
    'canonical_sphinx',
    'notfound.extension',
    'sphinx_design',
    'sphinx_reredirects',
    'sphinx_tabs.tabs',
    'sphinxcontrib.jquery',
    'sphinxext.opengraph',
    'sphinx_config_options',
    'sphinx_related_links',
    'sphinx_roles',
    'sphinx_terminal',
    'sphinx_youtube_links',
    'sphinxcontrib.cairosvgconverter',
    'sphinx_last_updated_by_git',
    'sphinx.ext.intersphinx',
    'sphinx_sitemap',
    'sphinx_remove_toctrees',
    'myst_parser',
]

# Additional MyST syntax
myst_enable_extensions = {
    'substitution',
    'deflist',
    'linkify',
    'attrs_block',
}

# Exclude from processing
exclude_patterns = [
    'html',
    'README.md',
    'config_options_cheat_sheet.md',
    'reference/release-notes/release-notes-template.md',
]

# Adds custom CSS files, located under 'html_static_path' or from external link
html_css_files = [
    'lxd_custom.css',
    'https://assets.ubuntu.com/v1/d86746ef-cookie_banner.css',
]

# Adds custom JavaScript files, located under 'html_static_path' or from external link
html_js_files = [
    'https://assets.ubuntu.com/v1/287a5e8f-bundle.js',
]

# Feedback button at the top; enabled by default
# To disable the button, uncomment the line below:

# disable_feedback_button = True

# Specifies a reST snippet to be prepended to each .rst file
# Defines a :center: role that centers table cell content.
# Defines a :h2: role that styles content for use with PDF generation.
# Defines woke-ignore and vale-ignore roles that can be used to mark content to be
# ignored by vale and woke checks
rst_prolog = """
.. role:: center
   :class: align-center
.. role:: h2
    :class: hclass2
.. role:: woke-ignore
    :class: woke-ignore
.. role:: vale-ignore
    :class: vale-ignore
"""


############################################################
### Misc LXD custom configuration
############################################################

# Use custom 404 page text
notfound_context = {
    'title': 'Page not found',
    'body': '<h1>Page not found</h1>\n\n<p><strong>Sorry, but the documentation page that you are looking for was not found.</strong></p>\n\n<p>Documentation changes over time, and pages are moved around. We try to redirect you to the updated content where possible, but unfortunately, that didn\'t work this time (maybe because the content you were looking for does not exist in this version of the documentation).</p>\n<p>You can try to use the navigation to locate the content you\'re looking for, or search for a similar page.</p>\n',
}

# Prevents making links from URLs that do not start with a protocol
myst_linkify_fuzzy_links = False
# Auto-generate HTML anchors down to heading level 7
# https://myst-parser.readthedocs.io/en/latest/syntax/optional.html#auto-generated-header-anchors
myst_heading_anchors = 7

myst_substitutions = {}
if os.path.exists('./substitutions.yaml'):
    with open('./substitutions.yaml', 'r') as fd:
        myst_substitutions.update(yaml.safe_load(fd.read()))
if os.path.exists('./related_topics.yaml'):
    with open('./related_topics.yaml', 'r') as fd:
        myst_substitutions.update(yaml.safe_load(fd.read()))

# Add configuration for intersphinx mapping
intersphinx_mapping = {
    'cloud-init': ('https://cloudinit.readthedocs.io/en/latest/', None),
    'imagebuilder': ('https://canonical-lxd-imagebuilder.readthedocs-hosted.com/en/latest/', None),
    'snap': ('https://snapcraft.io/docs/', None),
}

if ('LOCAL_SPHINX_BUILD' in os.environ) and (os.environ['LOCAL_SPHINX_BUILD'] == 'True'):
    swagger_url_scheme = '/api/#{{path}}'
else:
    swagger_url_scheme = '/lxd/latest/api/#{{path}}'

myst_url_schemes = {
    'http': None,
    'https': None,
    'swagger': swagger_url_scheme,
}

remove_from_toctrees = ['reference/manpages/lxc/*.md']

# Download and link swagger-ui files
if not os.path.isdir('.sphinx/deps/swagger-ui'):
    Repo.clone_from('https://github.com/swagger-api/swagger-ui', '.sphinx/deps/swagger-ui', depth=1)

os.makedirs('_static/swagger-ui/', exist_ok=True)

if not os.path.islink('_static/swagger-ui/swagger-ui-bundle.js'):
    os.symlink('../../.sphinx/deps/swagger-ui/dist/swagger-ui-bundle.js', '_static/swagger-ui/swagger-ui-bundle.js')
if not os.path.islink('_static/swagger-ui/swagger-ui-standalone-preset.js'):
    os.symlink('../../.sphinx/deps/swagger-ui/dist/swagger-ui-standalone-preset.js', '_static/swagger-ui/swagger-ui-standalone-preset.js')
if not os.path.islink('_static/swagger-ui/swagger-ui.css'):
    os.symlink('../../.sphinx/deps/swagger-ui/dist/swagger-ui.css', '_static/swagger-ui/swagger-ui.css')

### MAN PAGES ###

# Find path to lxc client (different for local builds and on RTD)

if os.environ.get('LOCAL_SPHINX_BUILD') == 'True':
    path = str(subprocess.check_output(['go', 'env', 'GOPATH'], encoding='utf-8').strip())
    lxc = os.path.join(path, 'bin', 'lxc')
    if os.path.isfile(lxc):
        print('Using ' + lxc + ' to generate man pages.')
    else:
        print('Cannot find lxc in ' + lxc)
        sys.exit(2)
else:
    lxc = '../lxc.bin'

# Generate man pages content

os.makedirs('.sphinx/deps/manpages', exist_ok=True)
if os.path.isfile(lxc):
    subprocess.run([lxc, 'manpage', '.sphinx/deps/manpages/', '--format=md'],
                   check=True)
else:
    print('No man page content generated.')

# Preprocess man pages content

for page in [x for x in os.listdir('.sphinx/deps/manpages')
             if os.path.isfile(os.path.join('.sphinx/deps/manpages/', x))]:

    # replace underscores with slashes to create a directory structure
    pagepath = page.replace('_', '/')

    # for each generated page, add an anchor, fix the title, and adjust the
    # heading levels
    with open(os.path.join('.sphinx/deps/manpages/', page), 'r') as mdfile:
        content = mdfile.readlines()

    os.makedirs(os.path.dirname(os.path.join('.sphinx/deps/manpages/', pagepath)),
                exist_ok=True)

    with open(os.path.join('.sphinx/deps/manpages/', pagepath), 'w') as mdfile:
        mdfile.write('(' + page + ')=\n')
        in_code_block = False
        for line in content:
            if line.startswith('###### Auto generated'):
                continue
            elif line.startswith('## '):
                mdfile.write('# `' + line[3:].rstrip() + '`\n')
            elif line.startswith('##'):
                mdfile.write(line[1:])
            elif line.startswith('```'):
                if not in_code_block and line.rstrip() == '```':
                    mdfile.write('```none\n')
                else:
                    mdfile.write(line)

                in_code_block = not in_code_block
            else:
                mdfile.write(line)

    # remove the input page (unless the file path doesn't change)
    if '_' in page:
        os.remove(os.path.join('.sphinx/deps/manpages/', page))

# Complete and copy man pages content

for folder, subfolders, files in os.walk('.sphinx/deps/manpages'):

    # for each subfolder, add toctrees to the parent page that
    # include the subpages
    for subfolder in subfolders:
        with open(os.path.join(folder, subfolder + '.md'), 'a') as parent:
            parent.write('```{toctree}\n:titlesonly:\n:glob:\n:hidden:\n\n' +
                         subfolder + '/*\n```\n')

    # for each file, if the content is different to what has been generated
    # before, copy the file to the reference/manpages folder
    # (copying all would mess up the incremental build)
    for f in files:
        sourcefile = os.path.join(folder, f)
        targetfile = os.path.join('reference/manpages/',
                                  os.path.relpath(folder,
                                                  '.sphinx/deps/manpages'),
                                  f)

        if (not os.path.isfile(targetfile) or
            not filecmp.cmp(sourcefile, targetfile, shallow=False)):

            os.makedirs(os.path.dirname(targetfile), exist_ok=True)
            shutil.copy2(sourcefile, targetfile)

### End MAN PAGES ###

############################################################
### Custom PDF/LaTeX configuration
############################################################

# Use LXD's custom LaTeX template because the one from canonical-sphinx introduces
# a bug with white-on-white text on most pages

with open(".sphinx/latex_elements_template.txt", "rt") as file:
    latex_config = file.read()

latex_elements = ast.literal_eval(latex_config.replace("$PROJECT", project))


###########################################
### Prevent indexing of older docs versions
###########################################

# Add RTD docs version slugs for versions that should not be indexed by search engines
noindex_versions = {"stable-5.0", "stable-4.0"}

rtd_version = os.environ.get("READTHEDOCS_VERSION", "")
html_context["seo_noindex"] = rtd_version in noindex_versions
