#-- copyright
# OpenProject is a project management system.
# Copyright (C) 2012-2014 the OpenProject Foundation (OPF)
#
# 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) 2006-2013 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 doc/COPYRIGHT.rdoc for more details.
#++

# This capsulates permissions a user has for a work package.  It caches based
# on the work package's project and is thus optimized for the context menu.
#
# This is no conern but it was placed here so that it will be removed together
# with the rest of the experimental API.

module Api
  module Experimental
    module Concerns
      class Can
        attr_accessor :user

        def initialize(user)
          self.user = user
        end

        def actions(wp)
          cache[wp].each_with_object([]) { |(k, v), a| a << k if v }
        end

        def allowed?(work_package, action)
          cache[work_package][action]
        end

        private

        def cache
          @cache ||= Hash.new do |hash, work_package|
            # copy checks for the move_work_packages permission. This makes
            # sense only because the work_packages/moves controller handles
            # copying multiple work packages.
            hash[work_package] = {
              :edit => edit_allowed?(work_package),
              :log_time => log_time_allowed?(work_package),
              :move => move_allowed?(work_package),
              :copy => move_allowed?(work_package),
              :duplicate => copy_allowed?(work_package), # duplicating is another form of copying
              :delete => delete_allowed?(work_package)
            }
          end
        end

        def edit_allowed?(work_package)
          @edit_cache ||= Hash.new do |hash, project|
            hash[project] = user.allowed_to?(:edit_work_packages, project)
          end

          @edit_cache[work_package.project] || work_package.new_statuses_allowed_to(user).present?
        end

        def log_time_allowed?(work_package)
          @log_time_cache ||= Hash.new do |hash, project|
            hash[project] = user.allowed_to?(:log_time, project)
          end

          @log_time_cache[work_package.project]
        end

        def move_allowed?(work_package)
          @move_cache ||= Hash.new do |hash, project|
            hash[project] = user.allowed_to?(:move_work_packages, project)
          end

          @move_cache[work_package.project]
        end

        def copy_allowed?(work_package)
          type_active_in_project?(work_package) && add_allowed?(work_package)
        end

        def delete_allowed?(work_package)
          @delete_cache ||= Hash.new do |hash, project|
            hash[project] = user.allowed_to?(:delete_work_packages, project)
          end

          @delete_cache[work_package.project]
        end

        def add_allowed?(work_package)
          @add_cache ||= Hash.new do |hash, project|
            hash[project] = user.allowed_to?(:add_work_packages, project)
          end

          @add_cache[work_package.project]
        end

        def type_active_in_project?(work_package)
          @type_active_cache ||= Hash.new do |hash, project|
            hash[project] = project.types.pluck(:id)
          end

          @type_active_cache[work_package.project].include?(work_package.type_id)
        end
      end
    end
  end
end