# Calendar.social
# Copyright (C) 2018  Gergely Polonkai
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# 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 Affero 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 <https://www.gnu.org/licenses/>.

"""Group related endpoints for Calendar.social
"""

from flask import Blueprint, abort, redirect, render_template, url_for
from flask_security import current_user, login_required

from calsocial.utils import RoutedMixin


class GroupBlueprint(Blueprint, RoutedMixin):
    def __init__(self):
        Blueprint.__init__(self, 'group', __name__)

        self.app = None

        RoutedMixin.register_routes(self)

    def init_app(self, app, url_prefix=None):
        """Initialise the blueprint, registering it with ``app``.
        """

        self.app = app

        app.register_blueprint(self, url_prefix=url_prefix)

    @staticmethod
    @RoutedMixin.route('/')
    def list_groups():
        """View to list all public groups known by this instance
        """

        from calsocial.models import db, Group, GroupMembership, GroupVisibility

        groups = Group.query

        if current_user.is_authenticated:
            groups = groups.outerjoin(GroupMembership) \
                           .filter(db.or_(Group.visibility == GroupVisibility.public,
                                          GroupMembership.profile == current_user.profile))
        else:
            groups = groups.filter(Group.visibility == GroupVisibility.public)

        return render_template('group/list.html', groups=groups)

    @staticmethod
    @login_required
    @RoutedMixin.route('/create', methods=['GET', 'POST'])
    def create():
        from datetime import datetime

        from .forms import GroupForm
        from .models import db, Group, GroupMemberLevel, GroupMembership

        form = GroupForm()

        if form.validate_on_submit():
            group = Group(created_by=current_user.profile)
            form.populate_obj(group)
            db.session.add(group)

            member = GroupMembership(group=group,
                                     profile=current_user.profile,
                                     level=GroupMemberLevel.admin,
                                     accepted_at=datetime.utcnow(),
                                     accepted_by=current_user.profile)
            db.session.add(member)

            db.session.commit()

            return redirect(url_for('group.list'))

        return render_template('group/create.html', form=form)

    @staticmethod
    @RoutedMixin.route('/<fqn>')
    def display(fqn):
        from .models import Group

        group = Group.get_by_fqn(fqn)

        if not group.visible_to(current_user.profile):
            abort(404)

        return render_template('group/display.html', group=group)