# ActsAsPermissible
module NoamBenAri
  module Acts #:nodoc:
    module Permissible #:nodoc:

      def self.included(base)
        base.extend ClassMethods  
      end

      module ClassMethods
        def acts_as_permissible
          has_many :<%= table_name %>, :as => :permissible, :dependent => :destroy
          <% unless options[:skip_roles] %>
          has_many :<%= role_membership_model_file_name.pluralize %>, :as => :roleable, :dependent => :destroy
          has_many :<%= role_model_file_name.pluralize %>, :through => :<%= role_membership_model_file_name.pluralize %>, :source => :<%= role_model_file_name %>
          <% end %>
          include NoamBenAri::Acts::Permissible::InstanceMethods
          extend NoamBenAri::Acts::Permissible::SingletonMethods
          
          alias_method :full_permissions_hash, :permissions_hash
        end
      end
      
      # This module contains class methods
      module SingletonMethods
        
        # Helper method to lookup for permissions for a given object.
        # This method is equivalent to obj.permissions.
        def find_permissions_for(obj)
          permissible = ActiveRecord::Base.send(:class_name_of_active_record_descendant, self).to_s
         
          <%= class_name %>.find(:all,
            :conditions => ["permissible_id = ? and permissible_type = ?", obj.id, permissible]
          )
        end
      end
      
      # This module contains instance methods
      module InstanceMethods
        
        # returns permissions in hash form
        # from all levels recursively
        def permissions_hash
          @permissions_hash ||= lambda do
            @permissions_hash = <%= table_name %>.inject({}) { |hsh,perm| hsh.merge(perm.to_hash) }.symbolize_keys!
            <% unless options[:skip_roles] -%><%= role_model_file_name %>s.each do |<%= role_model_file_name %>|
              merge_permissions!(<%= role_model_file_name %>.permissions_hash)
            end
            <% end -%>@permissions_hash
          end.call()
        end
        
        # accepts a permission identifier string or an array of permission identifier strings
        # and return true if the user has all of the permissions given by the parameters
        # false if not.
        def has_permission?(*perms)
          perms.all? {|perm| permissions_hash.include?(perm.to_sym) && (permissions_hash[perm.to_sym] == true) }
        end
        
        # accepts a permission identifier string or an array of permission identifier strings
        # and return true if the user has any of the permissions given by the parameters
        # false if none.
        def has_any_permission?(*perms)
          perms.any? {|perm| permissions_hash.include?(perm.to_sym) && (permissions_hash[perm.to_sym] == true) }
        end
        
        # Merges another permissible object's permissions into this permissible's permissions hash
        # In the case of identical keys, a false value wins over a true value.
        def merge_permissions!(other_permissions_hash)
          permissions_hash.merge!(other_permissions_hash) {|key,oldval,newval| oldval.nil? ? newval : oldval && newval}
        end

        # Resets permissions and then loads them.
        def reload_permissions!
          reset_permissions!
          permissions_hash
        end
        <% unless options[:skip_roles] %>
        def <%= role_model_file_name %>s_list
          list = []
          <%= role_model_file_name %>s.inject(list) do |list,<%= role_model_file_name %>|
             list << <%= role_model_file_name %>.name
             <%= role_model_file_name %>.<%= role_model_file_name.pluralize %>_list.inject(list) {|list,<%= role_model_file_name %>| list << <%= role_model_file_name %>}
          end
          list.uniq
        end
        
        def in_<%= role_model_file_name %>?(*<%= role_model_file_name %>_names)
          <%= role_model_file_name %>_names.all? {|<%= role_model_file_name %>| <%= role_model_file_name %>s_list.include?(<%= role_model_file_name %>) }
        end
        
        def in_any_<%= role_model_file_name %>?(*<%= role_model_file_name %>_names)
          <%= role_model_file_name %>_names.any? {|<%= role_model_file_name %>| <%= role_model_file_name %>s_list.include?(<%= role_model_file_name %>) }
        end

        <% end %>
        private
        # Nilifies permissions_hash instance variable.
        def reset_permissions!
          @permissions_hash = nil
        end
          
      end
    end
  end
end