# -*- coding: utf-8 -*-

# Copyright (C) 2017-2018 RhodeCode GmbH
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License, version 3
# (only), as published by the Free Software Foundation.
#
# This program 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 Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
# This program is dual-licensed. If you wish to learn more about the
# RhodeCode Enterprise Edition, including its added features, Support services,
# and proprietary license terms, please see https://rhodecode.com/licenses/
import pytz
import logging

from pyramid.view import view_config
from pyramid.response import Response
from webhelpers.feedgenerator import Rss201rev2Feed, Atom1Feed

from rhodecode.apps._base import RepoAppView
from rhodecode.lib import audit_logger
from rhodecode.lib import rc_cache
from rhodecode.lib import helpers as h
from rhodecode.lib.auth import (
    LoginRequired, HasRepoPermissionAnyDecorator)
from rhodecode.lib.diffs import DiffProcessor, LimitedDiffContainer
from rhodecode.lib.utils2 import str2bool, safe_int, md5_safe
from rhodecode.model.db import UserApiKeys, CacheKey

log = logging.getLogger(__name__)


class RepoFeedView(RepoAppView):
    def load_default_context(self):
        c = self._get_local_tmpl_context()


        self._load_defaults()
        return c

    def _get_config(self):
        import rhodecode
        config = rhodecode.CONFIG

        return {
            'language': 'en-us',
            'feed_ttl': '5',  # TTL of feed,
            'feed_include_diff':
                str2bool(config.get('rss_include_diff', False)),
            'feed_items_per_page':
                safe_int(config.get('rss_items_per_page', 20)),
            'feed_diff_limit':
                # we need to protect from parsing huge diffs here other way
                # we can kill the server
                safe_int(config.get('rss_cut_off_limit', 32 * 1024)),
        }

    def _load_defaults(self):
        _ = self.request.translate
        config = self._get_config()
        # common values for feeds
        self.description = _('Changes on %s repository')
        self.title = self.title = _('%s %s feed') % (self.db_repo_name, '%s')
        self.language = config["language"]
        self.ttl = config["feed_ttl"]
        self.feed_include_diff = config['feed_include_diff']
        self.feed_diff_limit = config['feed_diff_limit']
        self.feed_items_per_page = config['feed_items_per_page']

    def _changes(self, commit):
        diff_processor = DiffProcessor(
            commit.diff(), diff_limit=self.feed_diff_limit)
        _parsed = diff_processor.prepare(inline_diff=False)
        limited_diff = isinstance(_parsed, LimitedDiffContainer)

        return diff_processor, _parsed, limited_diff

    def _get_title(self, commit):
        return h.shorter(commit.message, 160)

    def _get_description(self, commit):
        _renderer = self.request.get_partial_renderer(
            'rhodecode:templates/feed/atom_feed_entry.mako')
        diff_processor, parsed_diff, limited_diff = self._changes(commit)
        filtered_parsed_diff, has_hidden_changes = self.path_filter.filter_patchset(parsed_diff)
        return _renderer(
            'body',
            commit=commit,
            parsed_diff=filtered_parsed_diff,
            limited_diff=limited_diff,
            feed_include_diff=self.feed_include_diff,
            diff_processor=diff_processor,
            has_hidden_changes=has_hidden_changes
        )

    def _set_timezone(self, date, tzinfo=pytz.utc):
        if not getattr(date, "tzinfo", None):
            date.replace(tzinfo=tzinfo)
        return date

    def _get_commits(self):
        return list(self.rhodecode_vcs_repo[-self.feed_items_per_page:])

    def uid(self, repo_id, commit_id):
        return '{}:{}'.format(md5_safe(repo_id), md5_safe(commit_id))

    @LoginRequired(auth_token_access=[UserApiKeys.ROLE_FEED])
    @HasRepoPermissionAnyDecorator(
        'repository.read', 'repository.write', 'repository.admin')
    @view_config(
        route_name='atom_feed_home', request_method='GET',
        renderer=None)
    def atom(self):
        """
        Produce an atom-1.0 feed via feedgenerator module
        """
        self.load_default_context()

        cache_namespace_uid = 'cache_repo_instance.{}_{}'.format(
            self.db_repo.repo_id, CacheKey.CACHE_TYPE_FEED)
        invalidation_namespace = CacheKey.REPO_INVALIDATION_NAMESPACE.format(
            repo_id=self.db_repo.repo_id)

        region = rc_cache.get_or_create_region('cache_repo_longterm',
                                               cache_namespace_uid)

        condition = not self.path_filter.is_enabled

        @region.conditional_cache_on_arguments(namespace=cache_namespace_uid,
                                               condition=condition)
        def generate_atom_feed(repo_id, _repo_name, _feed_type):
            feed = Atom1Feed(
                title=self.title % _repo_name,
                link=h.route_url('repo_summary', repo_name=_repo_name),
                description=self.description % _repo_name,
                language=self.language,
                ttl=self.ttl
            )

            for commit in reversed(self._get_commits()):
                date = self._set_timezone(commit.date)
                feed.add_item(
                    unique_id=self.uid(repo_id, commit.raw_id),
                    title=self._get_title(commit),
                    author_name=commit.author,
                    description=self._get_description(commit),
                    link=h.route_url(
                        'repo_commit', repo_name=_repo_name,
                        commit_id=commit.raw_id),
                    pubdate=date,)

            return feed.mime_type, feed.writeString('utf-8')

        inv_context_manager = rc_cache.InvalidationContext(
            uid=cache_namespace_uid, invalidation_namespace=invalidation_namespace)
        with inv_context_manager as invalidation_context:
            args = (self.db_repo.repo_id, self.db_repo.repo_name, 'atom',)
            # re-compute and store cache if we get invalidate signal
            if invalidation_context.should_invalidate():
                mime_type, feed = generate_atom_feed.refresh(*args)
            else:
                mime_type, feed = generate_atom_feed(*args)

            log.debug('Repo ATOM feed computed in %.3fs',
                      inv_context_manager.compute_time)

        response = Response(feed)
        response.content_type = mime_type
        return response

    @LoginRequired(auth_token_access=[UserApiKeys.ROLE_FEED])
    @HasRepoPermissionAnyDecorator(
        'repository.read', 'repository.write', 'repository.admin')
    @view_config(
        route_name='rss_feed_home', request_method='GET',
        renderer=None)
    def rss(self):
        """
        Produce an rss2 feed via feedgenerator module
        """
        self.load_default_context()

        cache_namespace_uid = 'cache_repo_instance.{}_{}'.format(
            self.db_repo.repo_id, CacheKey.CACHE_TYPE_FEED)
        invalidation_namespace = CacheKey.REPO_INVALIDATION_NAMESPACE.format(
            repo_id=self.db_repo.repo_id)
        region = rc_cache.get_or_create_region('cache_repo_longterm',
                                               cache_namespace_uid)

        condition = not self.path_filter.is_enabled

        @region.conditional_cache_on_arguments(namespace=cache_namespace_uid,
                                               condition=condition)
        def generate_rss_feed(repo_id, _repo_name, _feed_type):
            feed = Rss201rev2Feed(
                title=self.title % _repo_name,
                link=h.route_url('repo_summary', repo_name=_repo_name),
                description=self.description % _repo_name,
                language=self.language,
                ttl=self.ttl
            )

            for commit in reversed(self._get_commits()):
                date = self._set_timezone(commit.date)
                feed.add_item(
                    unique_id=self.uid(repo_id, commit.raw_id),
                    title=self._get_title(commit),
                    author_name=commit.author,
                    description=self._get_description(commit),
                    link=h.route_url(
                        'repo_commit', repo_name=_repo_name,
                        commit_id=commit.raw_id),
                    pubdate=date,)

            return feed.mime_type, feed.writeString('utf-8')

        inv_context_manager = rc_cache.InvalidationContext(
            uid=cache_namespace_uid, invalidation_namespace=invalidation_namespace)
        with inv_context_manager as invalidation_context:
            args = (self.db_repo.repo_id, self.db_repo.repo_name, 'rss',)
            # re-compute and store cache if we get invalidate signal
            if invalidation_context.should_invalidate():
                mime_type, feed = generate_rss_feed.refresh(*args)
            else:
                mime_type, feed = generate_rss_feed(*args)
            log.debug(
                'Repo RSS feed computed in %.3fs', inv_context_manager.compute_time)

        response = Response(feed)
        response.content_type = mime_type
        return response