# encoding: utf-8
module Mongoid
  module Threaded

    # This module contains convenience methods for document lifecycle that
    # resides on thread locals.
    module Lifecycle
      extend ActiveSupport::Concern

      private

      # Begin the assignment of attributes. While in this block embedded
      # documents will not autosave themselves in order to allow the document to
      # be in a valid state.
      #
      # @example Execute the assignment.
      #   _assigning do
      #     person.attributes = { :addresses => [ address ] }
      #   end
      #
      # @return [ Object ] The yielded value.
      #
      # @since 2.2.0
      def _assigning
        Threaded.begin("assign")
        yield
      ensure
        Threaded.exit("assign")
      end

      # Is the current thread in assigning mode?
      #
      # @example Is the current thread in assigning mode?
      #   proxy._assigning?
      #
      # @return [ true, false ] If the thread is assigning.
      #
      # @since 2.1.0
      def _assigning?
        Threaded.executing?("assign")
      end

      # Execute a block in binding mode.
      #
      # @example Execute in binding mode.
      #   binding do
      #     relation.push(doc)
      #   end
      #
      # @return [ Object ] The return value of the block.
      #
      # @since 2.1.0
      def _binding
        Threaded.begin("bind")
        yield
      ensure
        Threaded.exit("bind")
      end

      # Is the current thread in binding mode?
      #
      # @example Is the current thread in binding mode?
      #   proxy.binding?
      #
      # @return [ true, false ] If the thread is binding.
      #
      # @since 2.1.0
      def _binding?
        Threaded.executing?("bind")
      end

      # Execute a block in building mode.
      #
      # @example Execute in building mode.
      #   _building do
      #     relation.push(doc)
      #   end
      #
      # @return [ Object ] The return value of the block.
      #
      # @since 2.1.0
      def _building
        Threaded.begin("build")
        yield
      ensure
        Threaded.exit("build")
      end

      # Is the current thread in building mode?
      #
      # @example Is the current thread in building mode?
      #   proxy._building?
      #
      # @return [ true, false ] If the thread is building.
      #
      # @since 2.1.0
      def _building?
        Threaded.executing?("build")
      end

      # Is the current thread in creating mode?
      #
      # @example Is the current thread in creating mode?
      #   proxy.creating?
      #
      # @return [ true, false ] If the thread is creating.
      #
      # @since 2.1.0
      def _creating?
        Threaded.executing?("create")
      end

      # Execute a block in loading mode.
      #
      # @example Execute in loading mode.
      #   _loading do
      #     relation.push(doc)
      #   end
      #
      # @return [ Object ] The return value of the block.
      #
      # @since 2.3.2
      def _loading
        Threaded.begin("load")
        yield
      ensure
        Threaded.exit("load")
      end

      # Is the current thread in loading mode?
      #
      # @example Is the current thread in loading mode?
      #   proxy._loading?
      #
      # @return [ true, false ] If the thread is loading.
      #
      # @since 2.3.2
      def _loading?
        Threaded.executing?("load")
      end

      # Execute a block in loading revision mode.
      #
      # @example Execute in loading revision mode.
      #   _loading_revision do
      #     load_revision
      #   end
      #
      # @return [ Object ] The return value of the block.
      #
      # @since 2.3.4
      def _loading_revision
        Threaded.begin("load_revision")
        yield
      ensure
        Threaded.exit("load_revision")
      end

      module ClassMethods

        # Execute a block in creating mode.
        #
        # @example Execute in creating mode.
        #   creating do
        #     relation.push(doc)
        #   end
        #
        # @return [ Object ] The return value of the block.
        #
        # @since 2.1.0
        def _creating
          Threaded.begin("create")
          yield
        ensure
          Threaded.exit("create")
        end

        # Is the current thread in loading revision mode?
        #
        # @example Is the current thread in loading revision mode?
        #   proxy._loading_revision?
        #
        # @return [ true, false ] If the thread is loading a revision.
        #
        # @since 2.3.4
        def _loading_revision?
          Threaded.executing?("load_revision")
        end
      end
    end
  end
end