#-- encoding: UTF-8
#-- copyright
# OpenProject is an open source project management software.
# Copyright (C) 2012-2020 the OpenProject GmbH
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License version 3.
#
# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
# Copyright (C) 2006-2017 Jean-Philippe Lang
# Copyright (C) 2010-2013 the ChiliProject Team
#
# This program 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 2
# 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
#
# See docs/COPYRIGHT.rdoc for more details.
#++

class Group < Principal
  has_and_belongs_to_many :users,
                          join_table:   "#{table_name_prefix}group_users#{table_name_suffix}",
                          before_add: :fail_add,
                          after_remove: :user_removed

  acts_as_customizable

  before_destroy :remove_references_before_destroy

  alias_attribute(:groupname, :lastname)
  validates_presence_of :groupname
  validate :uniqueness_of_groupname
  validates_length_of :groupname, maximum: 30

  # HACK: We want to have the :preference association on the Principal to allow
  # for eager loading preferences.
  # However, the preferences are currently very user specific.  We therefore
  # remove the methods added by
  #   has_one :preference
  # to avoid accidental assignment and usage of preferences on groups.
  undef_method :preference,
               :preference=,
               :build_preference,
               :create_preference,
               :create_preference!

  prepend Destroy

  def to_s
    lastname.to_s
  end

  alias :name :to_s

  def user_removed(user)
    member_roles = MemberRole
                   .includes(member: :member_roles)
                   .where(inherited_from: members.joins(:member_roles).select('member_roles.id'))
                   .where(members: { user_id: user.id })

    project_ids = member_roles.map { |mr| mr.member.project_id }

    member_roles.each do |member_role|
      member_role.member.remove_member_role_and_destroy_member_if_last(member_role,
                                                                       prune_watchers: false)
    end

    Watcher.prune(user: user, project_id: project_ids)
  end

  # adds group members
  # meaning users that are members of the group
  def add_members!(users)
    user_ids = Array(users).map { |user_or_id| user_or_id.is_a?(Integer) ? user_or_id : user_or_id.id }

    ::Groups::AddUsersService
      .new(self, current_user: User.current)
      .call(user_ids)
  end

  private

  # Removes references that are not handled by associations
  def remove_references_before_destroy
    return if id.nil?

    deleted_user = DeletedUser.first

    WorkPackage.where(assigned_to_id: id).update_all(assigned_to_id: deleted_user.id)

    Journal::WorkPackageJournal.where(assigned_to_id: id)
      .update_all(assigned_to_id: deleted_user.id)
  end

  def uniqueness_of_groupname
    groups_with_name = Group.where('lastname = ? AND id <> ?', groupname, id ? id : 0).count
    if groups_with_name > 0
      errors.add :groupname, :taken
    end
  end

  def fail_add
    fail "Do not add users through association, use `group.add_members!` instead."
  end
end