#!/usr/bin/env python
# (c) 2012, Jan-Piet Mens <jpmens () gmail.com>
# (c) 2012-2014, Michael DeHaan <michael@ansible.com> and others
# (c) 2017 Ansible Project
#
# This file is part of Ansible
#
# Ansible is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Ansible is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Ansible.  If not, see <http://www.gnu.org/licenses/>.

from __future__ import absolute_import, division, print_function
__metaclass__ = type


import datetime
import glob
import optparse
import os
import re
import sys
import warnings
from collections import defaultdict
from distutils.version import LooseVersion
from pprint import PrettyPrinter

try:
    from html import escape as html_escape
except ImportError:
    # Python-3.2 or later
    import cgi

    def html_escape(text, quote=True):
        return cgi.escape(text, quote)

import jinja2
import yaml
from jinja2 import Environment, FileSystemLoader
from six import iteritems, string_types

from ansible.errors import AnsibleError
from ansible.module_utils._text import to_bytes, to_text
from ansible.plugins.loader import fragment_loader
from ansible.utils import plugin_docs
from ansible.utils.display import Display


#####################################################################################
# constants and paths

# if a module is added in a version of Ansible older than this, don't print the version added information
# in the module documentation because everyone is assumed to be running something newer than this already.
TOO_OLD_TO_BE_NOTABLE = 1.3

# Get parent directory of the directory this script lives in
MODULEDIR = os.path.abspath(os.path.join(
    os.path.dirname(os.path.realpath(__file__)), os.pardir, 'lib', 'ansible', 'modules'
))

# The name of the DOCUMENTATION template
EXAMPLE_YAML = os.path.abspath(os.path.join(
    os.path.dirname(os.path.realpath(__file__)), os.pardir, 'examples', 'DOCUMENTATION.yml'
))

_ITALIC = re.compile(r"I\(([^)]+)\)")
_BOLD = re.compile(r"B\(([^)]+)\)")
_MODULE = re.compile(r"M\(([^)]+)\)")
_URL = re.compile(r"U\(([^)]+)\)")
_LINK = re.compile(r"L\(([^)]+),([^)]+)\)")
_CONST = re.compile(r"C\(([^)]+)\)")
_RULER = re.compile(r"HORIZONTALLINE")

DEPRECATED = b" (D)"

pp = PrettyPrinter()
display = Display()


# kludge_ns gives us a kludgey way to set variables inside of loops that need to be visible outside
# the loop.  We can get rid of this when we no longer need to build docs with less than Jinja-2.10
# http://jinja.pocoo.org/docs/2.10/templates/#assignments
# With Jinja-2.10 we can use jinja2's namespace feature, restoring the namespace template portion
# of: fa5c0282a4816c4dd48e80b983ffc1e14506a1f5
NS_MAP = {}


def to_kludge_ns(key, value):
    NS_MAP[key] = value
    return ""


def from_kludge_ns(key):
    return NS_MAP[key]


# The max filter was added in Jinja2-2.10.  Until we can require that version, use this
def do_max(seq):
    return max(seq)


def rst_ify(text):
    ''' convert symbols like I(this is in italics) to valid restructured text '''

    try:
        t = _ITALIC.sub(r"*\1*", text)
        t = _BOLD.sub(r"**\1**", t)
        t = _MODULE.sub(r":ref:`\1 <\1_module>`", t)
        t = _LINK.sub(r"`\1 <\2>`_", t)
        t = _URL.sub(r"\1", t)
        t = _CONST.sub(r"``\1``", t)
        t = _RULER.sub(r"------------", t)
    except Exception as e:
        raise AnsibleError("Could not process (%s) : %s" % (text, e))

    return t


def html_ify(text):
    ''' convert symbols like I(this is in italics) to valid HTML '''

    if not isinstance(text, string_types):
        text = to_text(text)

    t = html_escape(text)
    t = _ITALIC.sub(r"<em>\1</em>", t)
    t = _BOLD.sub(r"<b>\1</b>", t)
    t = _MODULE.sub(r"<span class='module'>\1</span>", t)
    t = _URL.sub(r"<a href='\1'>\1</a>", t)
    t = _LINK.sub(r"<a href='\2'>\1</a>", t)
    t = _CONST.sub(r"<code>\1</code>", t)
    t = _RULER.sub(r"<hr/>", t)

    return t.strip()


def rst_fmt(text, fmt):
    ''' helper for Jinja2 to do format strings '''

    return fmt % (text)


def rst_xline(width, char="="):
    ''' return a restructured text line of a given length '''

    return char * width


def write_data(text, output_dir, outputname, module=None):
    ''' dumps module output to a file or the screen, as requested '''

    if output_dir is not None:
        if module:
            outputname = outputname % module

        if not os.path.exists(output_dir):
            os.makedirs(output_dir)
        fname = os.path.join(output_dir, outputname)
        fname = fname.replace(".py", "")
        with open(fname, 'wb') as f:
            f.write(to_bytes(text))
    else:
        print(text)


def get_plugin_info(module_dir, limit_to=None, verbose=False):
    '''
    Returns information about plugins and the categories that they belong to

    :arg module_dir: file system path to the top of the plugin directory
    :kwarg limit_to: If given, this is a list of plugin names to
        generate information for.  All other plugins will be ignored.
    :returns: Tuple of two dicts containing module_info, categories, and
        aliases and a set listing deprecated modules:

        :module_info: mapping of module names to information about them.  The fields of the dict are:

            :path: filesystem path to the module
            :deprecated: boolean.  True means the module is deprecated otherwise not.
            :aliases: set of aliases to this module name
            :metadata: The modules metadata (as recorded in the module)
            :doc: The documentation structure for the module
            :examples: The module's examples
            :returndocs: The module's returndocs

        :categories: maps category names to a dict.  The dict contains at
            least one key, '_modules' which contains a list of module names in
            that category.  Any other keys in the dict are subcategories with
            the same structure.

    '''

    categories = dict()
    module_info = defaultdict(dict)

    # * windows powershell modules have documentation stubs in python docstring
    #   format (they are not executed) so skip the ps1 format files
    # * One glob level for every module level that we're going to traverse
    files = (
        glob.glob("%s/*.py" % module_dir) +
        glob.glob("%s/*/*.py" % module_dir) +
        glob.glob("%s/*/*/*.py" % module_dir) +
        glob.glob("%s/*/*/*/*.py" % module_dir)
    )

    for module_path in files:
        # Do not list __init__.py files
        if module_path.endswith('__init__.py'):
            continue

        # Do not list blacklisted modules
        module = os.path.splitext(os.path.basename(module_path))[0]
        if module in plugin_docs.BLACKLIST['MODULE'] or module == 'base':
            continue

        # If requested, limit module documentation building only to passed-in
        # modules.
        if limit_to is not None and module.lower() not in limit_to:
            continue

        deprecated = False
        if module.startswith("_"):
            if os.path.islink(module_path):
                # Handle aliases
                source = os.path.splitext(os.path.basename(os.path.realpath(module_path)))[0]
                module = module.replace("_", "", 1)
                aliases = module_info[source].get('aliases', set())
                aliases.add(module)
                # In case we just created this via get()'s fallback
                module_info[source]['aliases'] = aliases
                continue
            else:
                # Handle deprecations
                module = module.replace("_", "", 1)
                deprecated = True

        #
        # Regular module to process
        #

        category = categories

        # Start at the second directory because we don't want the "vendor"
        mod_path_only = os.path.dirname(module_path[len(module_dir):])

        module_categories = []
        # build up the categories that this module belongs to
        for new_cat in mod_path_only.split('/')[1:]:
            if new_cat not in category:
                category[new_cat] = dict()
                category[new_cat]['_modules'] = []
            module_categories.append(new_cat)
            category = category[new_cat]

        category['_modules'].append(module)

        # the category we will use in links (so list_of_all_plugins can point to plugins/action_plugins/*'
        if module_categories:
            primary_category = module_categories[0]

        # use ansible core library to parse out doc metadata YAML and plaintext examples
        doc, examples, returndocs, metadata = plugin_docs.get_docstring(module_path, fragment_loader, verbose=verbose)

        # save all the information
        module_info[module] = {'path': module_path,
                               'source': os.path.relpath(module_path, module_dir),
                               'deprecated': deprecated,
                               'aliases': module_info[module].get('aliases', set()),
                               'metadata': metadata,
                               'doc': doc,
                               'examples': examples,
                               'returndocs': returndocs,
                               'categories': module_categories,
                               'primary_category': primary_category,
                               }

    # keep module tests out of becoming module docs
    if 'test' in categories:
        del categories['test']

    return module_info, categories


def generate_parser():
    ''' generate an optparse parser '''

    p = optparse.OptionParser(
        version='%prog 1.0',
        usage='usage: %prog [options] arg1 arg2',
        description='Generate module documentation from metadata',
    )

    p.add_option("-A", "--ansible-version", action="store", dest="ansible_version", default="unknown", help="Ansible version number")
    p.add_option("-M", "--module-dir", action="store", dest="module_dir", default=MODULEDIR, help="Ansible library path")
    p.add_option("-P", "--plugin-type", action="store", dest="plugin_type", default='module', help="The type of plugin (module, lookup, etc)")
    p.add_option("-T", "--template-dir", action="store", dest="template_dir", default="hacking/templates", help="directory containing Jinja2 templates")
    p.add_option("-t", "--type", action='store', dest='type', choices=['rst'], default='rst', help="Document type")
    p.add_option("-o", "--output-dir", action="store", dest="output_dir", default=None, help="Output directory for module files")
    p.add_option("-I", "--includes-file", action="store", dest="includes_file", default=None, help="Create a file containing list of processed modules")
    p.add_option("-l", "--limit-to-modules", '--limit-to', action="store", dest="limit_to", default=None,
                 help="Limit building module documentation to comma-separated list of plugins. Specify non-existing plugin name for no plugins.")
    p.add_option('-V', action='version', help='Show version number and exit')
    p.add_option('-v', '--verbose', dest='verbosity', default=0, action="count", help="verbose mode (increase number of 'v's for more)")
    return p


def jinja2_environment(template_dir, typ, plugin_type):

    env = Environment(loader=FileSystemLoader(template_dir),
                      variable_start_string="@{",
                      variable_end_string="}@",
                      trim_blocks=True)
    env.globals['xline'] = rst_xline

    # Can be removed (and template switched to use namespace) when we no longer need to build
    # with <Jinja-2.10
    env.globals['to_kludge_ns'] = to_kludge_ns
    env.globals['from_kludge_ns'] = from_kludge_ns
    if 'max' not in env.filters:
        # Jinja < 2.10
        env.filters['max'] = do_max

    templates = {}
    if typ == 'rst':
        env.filters['convert_symbols_to_format'] = rst_ify
        env.filters['html_ify'] = html_ify
        env.filters['fmt'] = rst_fmt
        env.filters['xline'] = rst_xline
        templates['plugin'] = env.get_template('plugin.rst.j2')

        if plugin_type == 'module':
            name = 'modules'
        else:
            name = 'plugins'

        templates['category_list'] = env.get_template('%s_by_category.rst.j2' % name)
        templates['support_list'] = env.get_template('%s_by_support.rst.j2' % name)
        templates['list_of_CATEGORY_modules'] = env.get_template('list_of_CATEGORY_%s.rst.j2' % name)
    else:
        raise Exception("Unsupported format type: %s" % typ)

    return templates


def too_old(added):
    if not added:
        return False
    try:
        added_tokens = str(added).split(".")
        readded = added_tokens[0] + "." + added_tokens[1]
        added_float = float(readded)
    except ValueError as e:
        warnings.warn("Could not parse %s: %s" % (added, str(e)))
        return False
    return added_float < TOO_OLD_TO_BE_NOTABLE


def process_plugins(module_map, templates, outputname, output_dir, ansible_version, plugin_type):
    for module in module_map:

        display.display("rendering: %s" % module)
        fname = module_map[module]['path']
        display.vvvvv(pp.pformat(('process_plugins info: ', module_map[module])))

        # crash if module is missing documentation and not explicitly hidden from docs index
        if module_map[module]['doc'] is None:
            display.error("%s MISSING DOCUMENTATION" % (fname,))
            _doc = {plugin_type: module,
                    'version_added': '2.4',
                    'filename': fname}
            module_map[module]['doc'] = _doc
            # continue

        # Going to reference this heavily so make a short name to reference it by
        doc = module_map[module]['doc']
        display.vvvvv(pp.pformat(('process_plugins doc: ', doc)))

        # add some defaults for plugins that dont have most of the info
        doc['module'] = doc.get('module', module)
        doc['version_added'] = doc.get('version_added', 'historical')

        doc['plugin_type'] = plugin_type

        if module_map[module]['deprecated'] and 'deprecated' not in doc:
            display.warning("%s PLUGIN MISSING DEPRECATION DOCUMENTATION: %s" % (fname, 'deprecated'))

        required_fields = ('short_description',)
        for field in required_fields:
            if field not in doc:
                display.warning("%s PLUGIN MISSING field '%s'" % (fname, field))

        not_nullable_fields = ('short_description',)
        for field in not_nullable_fields:
            if field in doc and doc[field] in (None, ''):
                print("%s: WARNING: MODULE field '%s' DOCUMENTATION is null/empty value=%s" % (fname, field, doc[field]))

        if 'version_added' not in doc:
            display.error("*** ERROR: missing version_added in: %s ***\n" % module)

        #
        # The present template gets everything from doc so we spend most of this
        # function moving data into doc for the template to reference
        #

        if module_map[module]['aliases']:
            doc['aliases'] = module_map[module]['aliases']

        # don't show version added information if it's too old to be called out
        added = 0
        if doc['version_added'] == 'historical':
            del doc['version_added']
        else:
            added = doc['version_added']

        # Strip old version_added for the module
        if too_old(added):
            del doc['version_added']

        option_names = []

        if 'options' in doc and doc['options']:
            for (k, v) in iteritems(doc['options']):
                # Error out if there's no description
                if 'description' not in doc['options'][k]:
                    raise AnsibleError("Missing required description for option %s in %s " % (k, module))

                # Error out if required isn't a boolean (people have been putting
                # information on when something is required in here.  Those need
                # to go in the description instead).
                required_value = doc['options'][k].get('required', False)
                if not isinstance(required_value, bool):
                    raise AnsibleError("Invalid required value '%s' for option '%s' in '%s' (must be truthy)" % (required_value, k, module))

                # Strip old version_added information for options
                if 'version_added' in doc['options'][k] and too_old(doc['options'][k]['version_added']):
                    del doc['options'][k]['version_added']

                # Make sure description is a list of lines for later formatting
                if not isinstance(doc['options'][k]['description'], list):
                    doc['options'][k]['description'] = [doc['options'][k]['description']]

                option_names.append(k)

        option_names.sort()

        doc['option_keys'] = option_names
        doc['filename'] = fname
        doc['source'] = module_map[module]['source']
        doc['docuri'] = doc['module'].replace('_', '-')
        doc['now_date'] = datetime.date.today().strftime('%Y-%m-%d')
        doc['ansible_version'] = ansible_version

        # check the 'deprecated' field in doc. We expect a dict potentially with 'why', 'version', and 'alternative' fields
        # examples = module_map[module]['examples']
        # print('\n\n%s: type of examples: %s\n' % (module, type(examples)))
        # if examples and not isinstance(examples, (str, unicode, list)):
        #    raise TypeError('module %s examples is wrong type (%s): %s' % (module, type(examples), examples))

        # use 'examples' for 'plainexamples' if 'examples' is a string
        if isinstance(module_map[module]['examples'], string_types):
            doc['plainexamples'] = module_map[module]['examples']  # plain text
        else:
            doc['plainexamples'] = ''

        doc['metadata'] = module_map[module]['metadata']

        display.vvvvv(pp.pformat(module_map[module]))
        if module_map[module]['returndocs']:
            try:
                doc['returndocs'] = yaml.safe_load(module_map[module]['returndocs'])
            except Exception as e:
                print("%s:%s:yaml error:%s:returndocs=%s" % (fname, module, e, module_map[module]['returndocs']))
                doc['returndocs'] = None
        else:
            doc['returndocs'] = None

        doc['author'] = doc.get('author', ['UNKNOWN'])
        if isinstance(doc['author'], string_types):
            doc['author'] = [doc['author']]

        display.v('about to template %s' % module)
        display.vvvvv(pp.pformat(doc))
        text = templates['plugin'].render(doc)
        if LooseVersion(jinja2.__version__) < LooseVersion('2.10'):
            # jinja2 < 2.10's indent filter indents blank lines.  Cleanup
            text = re.sub(' +\n', '\n', text)

        write_data(text, output_dir, outputname, module)


def process_categories(plugin_info, categories, templates, output_dir, output_name, plugin_type):
    for category in sorted(categories.keys()):
        module_map = categories[category]
        category_filename = output_name % category

        display.display("*** recording category %s in %s ***" % (category, category_filename))

        # start a new category file

        category_name = category.replace("_", " ")
        category_title = category_name.title()

        subcategories = dict((k, v) for k, v in module_map.items() if k != '_modules')
        template_data = {'title': category_title,
                         'category_name': category_name,
                         'category': module_map,
                         'subcategories': subcategories,
                         'module_info': plugin_info,
                         'plugin_type': plugin_type
                         }

        text = templates['list_of_CATEGORY_modules'].render(template_data)
        write_data(text, output_dir, category_filename)


def process_support_levels(plugin_info, templates, output_dir, plugin_type):
    supported_by = {'Ansible Core Team': {'slug': 'core_supported',
                                          'modules': [],
                                          'output': 'core_maintained.rst',
                                          'blurb': "These are :doc:`modules maintained by the"
                                                   " Ansible Core Team<core_maintained>` and will always ship"
                                                   " with Ansible itself."},
                    'Ansible Network Team': {'slug': 'network_supported',
                                             'modules': [],
                                             'output': 'network_maintained.rst',
                                             'blurb': "These are :doc:`modules maintained by the"
                                                      " Ansible Network Team<network_maintained>` in"
                                                      " a relationship similar to how the Ansible Core Team"
                                                      " maintains the Core modules."},
                    'Ansible Partners': {'slug': 'partner_supported',
                                         'modules': [],
                                         'output': 'partner_maintained.rst',
                                         'blurb': """
Some examples of :doc:`Certified Modules<partner_maintained>` are those submitted by other
companies. Maintainers of these types of modules must watch for any issues reported or pull requests
raised against the module.

The Ansible Core Team will review all modules becoming certified.  Core committers will review
proposed changes to existing Certified Modules once the community maintainers of the module have
approved the changes. Core committers will also ensure that any issues that arise due to Ansible
engine changes will be remediated.  Also, it is strongly recommended (but not presently required)
for these types of modules to have unit tests.

These modules are currently shipped with Ansible, but might be shipped separately in the future.
"""},
                    'Ansible Community': {'slug': 'community_supported',
                                          'modules': [],
                                          'output': 'community_maintained.rst',
                                          'blurb': """
These are :doc:`modules maintained by the Ansible Community<community_maintained>`.  They **are
not** supported by the Ansible Core Team or by companies/partners associated to the module.

They are still fully usable, but the response rate to issues is purely up to the community.  Best
effort support will be provided but is not covered under any support contracts.

These modules are currently shipped with Ansible, but will most likely be shipped separately in the future.
                                          """},
                    }

    # only gen support pages for modules for now, need to split and namespace templates and generated docs
    if plugin_type == 'plugins':
        return
    # Separate the modules by support_level
    for module, info in plugin_info.items():
        if not info.get('metadata', None):
            display.warning('no metadata for %s' % module)
            continue
        if info['metadata']['supported_by'] == 'core':
            supported_by['Ansible Core Team']['modules'].append(module)
        elif info['metadata']['supported_by'] == 'network':
            supported_by['Ansible Network Team']['modules'].append(module)
        elif info['metadata']['supported_by'] == 'certified':
            supported_by['Ansible Partners']['modules'].append(module)
        elif info['metadata']['supported_by'] == 'community':
            supported_by['Ansible Community']['modules'].append(module)
        else:
            raise AnsibleError('Unknown supported_by value: %s' % info['metadata']['supported_by'])

    # Render the module lists
    for maintainers, data in supported_by.items():
        template_data = {'maintainers': maintainers,
                         'modules': data['modules'],
                         'slug': data['slug'],
                         'module_info': plugin_info,
                         'plugin_type': plugin_type
                         }
        text = templates['support_list'].render(template_data)
        write_data(text, output_dir, data['output'])


def validate_options(options):
    ''' validate option parser options '''

    if not options.module_dir:
        sys.exit("--module-dir is required", file=sys.stderr)
    if not os.path.exists(options.module_dir):
        sys.exit("--module-dir does not exist: %s" % options.module_dir, file=sys.stderr)
    if not options.template_dir:
        sys.exit("--template-dir must be specified")


def main():

    # INIT
    p = generate_parser()
    (options, args) = p.parse_args()
    validate_options(options)
    display.verbosity = options.verbosity
    plugin_type = options.plugin_type

    # prep templating
    templates = jinja2_environment(options.template_dir, options.type, plugin_type)

    # set file/directory structure
    if plugin_type == 'module':
        # trim trailing s off of plugin_type for plugin_type=='modules'. ie 'copy_module.rst'
        outputname = '%s_' + '%s.rst' % plugin_type
        output_dir = options.output_dir
    else:
        # for plugins, just use 'ssh.rst' vs 'ssh_module.rst'
        outputname = '%s.rst'
        output_dir = '%s/plugins/%s' % (options.output_dir, plugin_type)

    display.vv('output name: %s' % outputname)
    display.vv('output dir: %s' % output_dir)

    # Convert passed-in limit_to to None or list of modules.
    if options.limit_to is not None:
        options.limit_to = [s.lower() for s in options.limit_to.split(",")]

    plugin_info, categories = get_plugin_info(options.module_dir, limit_to=options.limit_to, verbose=(options.verbosity > 0))

    categories['all'] = {'_modules': plugin_info.keys()}

    display.vvv(pp.pformat(categories))
    display.vvvvv(pp.pformat(plugin_info))

    # Transform the data
    if options.type == 'rst':
        display.v('Generating rst')
        for key, record in plugin_info.items():
            display.vv(key)
            display.vvvvv(pp.pformat(('record', record)))
            if record.get('doc', None):
                short_desc = record['doc']['short_description']
                if short_desc is None:
                    display.warning('short_description for %s is None' % key)
                    short_desc = ''
                record['doc']['short_description'] = rst_ify(short_desc)

    if plugin_type == 'module':
        display.v('Generating Categories')
        # Write module master category list
        category_list_text = templates['category_list'].render(categories=sorted(categories.keys()))
        category_index_name = '%ss_by_category.rst' % plugin_type
        write_data(category_list_text, output_dir, category_index_name)

    # Render all the individual plugin pages
    display.v('Generating plugin pages')
    process_plugins(plugin_info, templates, outputname, output_dir, options.ansible_version, plugin_type)

    # Render all the categories for modules
    if plugin_type == 'module':
        display.v('Generating Category lists')
        category_list_name_template = 'list_of_%s_' + '%ss.rst' % plugin_type
        process_categories(plugin_info, categories, templates, output_dir, category_list_name_template, plugin_type)

        # Render all the categories for modules
        process_support_levels(plugin_info, templates, output_dir, plugin_type)


if __name__ == '__main__':
    main()