# Copyright (c) 2013 Mirantis Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
# implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import os

import flask
from oslo.config import cfg

from dashboard import memory_storage
from stackalytics.openstack.common import log as logging
from stackalytics.processor import runtime_storage
from stackalytics.processor import utils


LOG = logging.getLogger(__name__)


def get_vault():
    vault = getattr(flask.current_app, 'stackalytics_vault', None)
    if not vault:
        try:
            vault = {}
            runtime_storage_inst = runtime_storage.get_runtime_storage(
                cfg.CONF.runtime_storage_uri)
            vault['runtime_storage'] = runtime_storage_inst
            vault['memory_storage'] = memory_storage.get_memory_storage(
                memory_storage.MEMORY_STORAGE_CACHED)

            init_releases(vault)

            flask.current_app.stackalytics_vault = vault
        except Exception as e:
            LOG.critical('Failed to initialize application: %s', e)
            LOG.exception(e)
            flask.abort(500)

    if not getattr(flask.request, 'stackalytics_updated', None):
        flask.request.stackalytics_updated = True
        memory_storage_inst = vault['memory_storage']
        have_updates = memory_storage_inst.update(
            vault['runtime_storage'].get_update(os.getpid()))

        if have_updates:
            init_releases(vault)
            init_module_groups(vault)

    return vault


def get_memory_storage():
    return get_vault()['memory_storage']


def init_releases(vault):
    runtime_storage_inst = vault['runtime_storage']
    releases = runtime_storage_inst.get_by_key('releases')
    releases_map = {}

    if releases:
        vault['start_date'] = releases[0]['end_date']
        vault['end_date'] = releases[-1]['end_date']
        start_date = releases[0]['end_date']
        for r in releases[1:]:
            r['start_date'] = start_date
            start_date = r['end_date']
        releases_map = dict((r['release_name'].lower(), r)
                            for r in releases[1:])

    vault['releases'] = releases_map


def init_module_groups(vault):
    runtime_storage_inst = vault['runtime_storage']
    memory_storage_inst = vault['memory_storage']

    module_index = {}
    module_id_index = {}
    module_groups = runtime_storage_inst.get_by_key('module_groups') or []

    module_groups.append({'module_group_name': 'All',
                          'modules': set(memory_storage_inst.get_modules())})

    for module_group in module_groups:
        module_group_name = module_group['module_group_name']
        module_group_id = module_group_name.lower()

        module_id_index[module_group_id] = {
            'group': True,
            'id': module_group_id,
            'text': module_group_name,
            'modules': [m.lower() for m in module_group['modules']],
        }

        modules = module_group['modules']
        for module in modules:
            if module in module_index:
                module_index[module].add(module_group_id)
            else:
                module_index[module] = set([module_group_id])

    for module in memory_storage_inst.get_modules():
        module_id_index[module] = {
            'id': module.lower(),
            'text': module,
            'modules': [module.lower()],
        }

    vault['module_group_index'] = module_index
    vault['module_id_index'] = module_id_index
    vault['module_groups'] = module_groups


def get_release_options():
    runtime_storage_inst = get_vault()['runtime_storage']
    releases = (runtime_storage_inst.get_by_key('releases') or [None])[1:]
    releases.append({'release_name': 'all'})
    releases.reverse()
    return releases


def get_user_from_runtime_storage(user_id):
    runtime_storage_inst = get_vault()['runtime_storage']
    return utils.load_user(runtime_storage_inst, user_id)


def resolve_modules(module_ids):
    module_id_index = get_vault().get('module_id_index') or {}
    modules = set()
    for module_id in module_ids:
        if module_id in module_id_index:
            modules |= set(module_id_index[module_id]['modules'])
    return modules