#
#    Copyright (C) 2017 SUSE LLC.
#
# This file is part of cloud-init. See LICENSE file for license information.

"""zypper_add_repo: Add zyper repositories to the system"""

import configobj
import os
from textwrap import dedent

from cloudinit.config.schema import get_schema_doc
from cloudinit import log as logging
from cloudinit.settings import PER_ALWAYS
from cloudinit import util

distros = ['opensuse', 'sles']

schema = {
    'id': 'cc_zypper_add_repo',
    'name': 'ZypperAddRepo',
    'title': 'Configure zypper behavior and add zypper repositories',
    'description': dedent("""\
        Configure zypper behavior by modifying /etc/zypp/zypp.conf. The
        configuration writer is "dumb" and will simply append the provided
        configuration options to the configuration file. Option settings
        that may be duplicate will be resolved by the way the zypp.conf file
        is parsed. The file is in INI format.
        Add repositories to the system. No validation is performed on the
        repository file entries, it is assumed the user is familiar with
        the zypper repository file format."""),
    'distros': distros,
    'examples': [dedent("""\
        zypper:
          repos:
            - id: opensuse-oss
              name: os-oss
              baseurl: http://dl.opensuse.org/dist/leap/v/repo/oss/
              enabled: 1
              autorefresh: 1
            - id: opensuse-oss-update
              name: os-oss-up
              baseurl: http://dl.opensuse.org/dist/leap/v/update
              # any setting per
              # https://en.opensuse.org/openSUSE:Standards_RepoInfo
              # enable and autorefresh are on by default
          config:
            reposdir: /etc/zypp/repos.dir
            servicesdir: /etc/zypp/services.d
            download.use_deltarpm: true
            # any setting in /etc/zypp/zypp.conf
    """)],
    'frequency': PER_ALWAYS,
    'type': 'object',
    'properties': {
        'zypper': {
            'type': 'object',
            'properties': {
                'repos': {
                    'type': 'array',
                    'items': {
                        'type': 'object',
                        'properties': {
                            'id': {
                                'type': 'string',
                                'description': dedent("""\
                                    The unique id of the repo, used when
                                     writing
                                    /etc/zypp/repos.d/<id>.repo.""")
                            },
                            'baseurl': {
                                'type': 'string',
                                'format': 'uri',   # built-in format type
                                'description': 'The base repositoy URL'
                            }
                        },
                        'required': ['id', 'baseurl'],
                        'additionalProperties': True
                    },
                    'minItems': 1
                },
                'config': {
                    'type': 'object',
                    'description': dedent("""\
                        Any supported zypo.conf key is written to
                        /etc/zypp/zypp.conf'""")
                }
            },
            'required': [],
            'minProperties': 1,  # Either config or repo must be provided
            'additionalProperties': False,  # only repos and config allowed
        }
    }
}

__doc__ = get_schema_doc(schema)  # Supplement python help()

LOG = logging.getLogger(__name__)


def _canonicalize_id(repo_id):
    repo_id = repo_id.replace(" ", "_")
    return repo_id


def _format_repo_value(val):
    if isinstance(val, bool):
        # zypp prefers 1/0
        return 1 if val else 0
    if isinstance(val, (list, tuple)):
        return "\n    ".join([_format_repo_value(v) for v in val])
    if not isinstance(val, str):
        return str(val)
    return val


def _format_repository_config(repo_id, repo_config):
    to_be = configobj.ConfigObj()
    to_be[repo_id] = {}
    # Do basic translation of the items -> values
    for (k, v) in repo_config.items():
        # For now assume that people using this know the format
        # of zypper repos  and don't verify keys/values further
        to_be[repo_id][k] = _format_repo_value(v)
    lines = to_be.write()
    return "\n".join(lines)


def _write_repos(repos, repo_base_path):
    """Write the user-provided repo definition files
    @param repos: A list of repo dictionary objects provided by the user's
        cloud config.
    @param repo_base_path: The directory path to which repo definitions are
        written.
    """

    if not repos:
        return
    valid_repos = {}
    for index, user_repo_config in enumerate(repos):
        # Skip on absent required keys
        missing_keys = set(['id', 'baseurl']).difference(set(user_repo_config))
        if missing_keys:
            LOG.warning(
                "Repo config at index %d is missing required config keys: %s",
                index, ",".join(missing_keys))
            continue
        repo_id = user_repo_config.get('id')
        canon_repo_id = _canonicalize_id(repo_id)
        repo_fn_pth = os.path.join(repo_base_path, "%s.repo" % (canon_repo_id))
        if os.path.exists(repo_fn_pth):
            LOG.info("Skipping repo %s, file %s already exists!",
                     repo_id, repo_fn_pth)
            continue
        elif repo_id in valid_repos:
            LOG.info("Skipping repo %s, file %s already pending!",
                     repo_id, repo_fn_pth)
            continue

        # Do some basic key formatting
        repo_config = dict(
            (k.lower().strip().replace("-", "_"), v)
            for k, v in user_repo_config.items()
            if k and k != 'id')

        # Set defaults if not present
        for field in ['enabled', 'autorefresh']:
            if field not in repo_config:
                repo_config[field] = '1'

        valid_repos[repo_id] = (repo_fn_pth, repo_config)

    for (repo_id, repo_data) in valid_repos.items():
        repo_blob = _format_repository_config(repo_id, repo_data[-1])
        util.write_file(repo_data[0], repo_blob)


def _write_zypp_config(zypper_config):
    """Write to the default zypp configuration file /etc/zypp/zypp.conf"""
    if not zypper_config:
        return
    zypp_config = '/etc/zypp/zypp.conf'
    zypp_conf_content = util.load_file(zypp_config)
    new_settings = ['# Added via cloud.cfg']
    for setting, value in zypper_config.items():
        if setting == 'configdir':
            msg = 'Changing the location of the zypper configuration is '
            msg += 'not supported, skipping "configdir" setting'
            LOG.warning(msg)
            continue
        if value:
            new_settings.append('%s=%s' % (setting, value))
    if len(new_settings) > 1:
        new_config = zypp_conf_content + '\n'.join(new_settings)
    else:
        new_config = zypp_conf_content
    util.write_file(zypp_config, new_config)


def handle(name, cfg, _cloud, log, _args):
    zypper_section = cfg.get('zypper')
    if not zypper_section:
        LOG.debug(("Skipping module named %s,"
                   " no 'zypper' relevant configuration found"), name)
        return
    repos = zypper_section.get('repos')
    if not repos:
        LOG.debug(("Skipping module named %s,"
                   " no 'repos' configuration found"), name)
        return
    zypper_config = zypper_section.get('config', {})
    repo_base_path = zypper_config.get('reposdir', '/etc/zypp/repos.d/')

    _write_zypp_config(zypper_config)
    _write_repos(repos, repo_base_path)

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