StateMachine => AASM

migration.md

included do
  # STATES: :draft | :published | :deleted
  
  state_machine :state, initial: TheCommentsBase.config.default_state do
    # events
    event :to_draft do
      transition all - :draft => :draft
    end

    event :to_published do
      transition all - :published => :published
    end

    event :to_deleted do
      transition any - :deleted => :deleted
    end

    # transition callbacks
    after_transition any => any do |comment|
      @comment     = comment
      @owner       = comment.user
      @holder      = comment.holder
      @commentable = comment.commentable
    end

    # between delete, draft and published
    after_transition [ :deleted, :draft, :published ] => [ :draft, :published ] do |comment, transition|
      from = transition.from_name
      to   = transition.to_name

      if from.to_s == 'deleted'
        comment.mark_as_ham
        @owner.try :recalculate_my_comments_counter!
      end

      if @holder
        @holder.update_columns({
          "#{ to }_comcoms_count"   => @holder.send("#{ to }_comcoms_count")   + 1,
          "#{ from }_comcoms_count" => @holder.send("#{ from }_comcoms_count") - 1
        })
      end

      if @commentable
        @commentable.update_columns({
          "#{ to }_comments_count"   => @commentable.send("#{ to }_comments_count")   + 1,
          "#{ from }_comments_count" => @commentable.send("#{ from }_comments_count") - 1
        })
      end
    end

    # to deleted (cascade like query)
    after_transition [ :draft, :published ] => :deleted do |comment|
      ids = comment.self_and_descendants.map(&:id)
      ::Comment.where(id: ids).update_all(state: :deleted)

      @owner.try       :recalculate_my_comments_counter!
      @holder.try      :recalculate_comcoms_counters!
      @commentable.try :recalculate_comments_counters!
    end
  end
end

class_methods do
  COMMENT_STATES = %i[ draft published deleted ]
end

included do
  include ::AASM

  scope :with_state, ->(states) { where state: Array.wrap(states) }

  aasm column: :state, whiny_transitions: true do
    # state :draft,     initial: true
    # state :published, initial: false
    # state :deleted,   initial: false
    ::Comment::COMMENT_STATES.each do |_state|
      state _state, initial: _state == TheCommentsBase.config.default_state.to_sym
    end

    # event: to_draft
    # event: to_published
    # event: to_deleted
    ::Comment::COMMENT_STATES.each do |_state|
      event "to_#{ _state }" do
        before do
          @from = state.to_sym
          @from = TheCommentsBase.config.default_state.to_sym if @from.blank?
        end

        after do
          @to = state.to_sym
        end

        after do
          define_common_aasm_variables

          # between delete, draft and published
          if %i[ draft published deleted ].include?(@from) && %i[ draft published ].include?(@to)
            move_from_any_to_draft_or_published
          end

          # to deleted (cascade like query)
          if %i[ draft published ].include?(@from) && @to == :deleted
            move_from_draft_or_published_to_deleted
          end
        end

        transitions \
          from: ::Comment::COMMENT_STATES - [_state],
          to: _state
      end
    end
  end

  def define_common_aasm_variables
    @comment     = self
    @owner       = @comment.user
    @holder      = @comment.holder
    @commentable = @comment.commentable
  end

  def move_from_any_to_draft_or_published
    if @from.to_s == 'deleted'
      @comment.mark_as_ham
      @owner.try :recalculate_my_comments_counter!
    end

    if @holder
      @holder.update_columns({
        "#{ @to }_comcoms_count"   => @holder.send("#{ @to }_comcoms_count")   + 1,
        "#{ @from }_comcoms_count" => @holder.send("#{ @from }_comcoms_count") - 1
      })
    end

    if @commentable
      @commentable.update_columns({
        "#{ @to }_comments_count"   => @commentable.send("#{ @to }_comments_count")   + 1,
        "#{ @from }_comments_count" => @commentable.send("#{ @from }_comments_count") - 1
      })
    end
  end

  def move_from_draft_or_published_to_deleted
    ids = @comment.self_and_descendants.map(&:id)
    ::Comment.where(id: ids).update_all(state: :deleted)

    @owner.try       :recalculate_my_comments_counter!
    @holder.try      :recalculate_comcoms_counters!
    @commentable.try :recalculate_comments_counters!
  end
end