class Asciidoctor::AbstractBlock

def <<(block)
  # parent assignment pending refactor
  #block.parent = self
  @blocks << block
end

def assign_caption(caption = nil, key = nil)
  return unless title? || !@caption
  if caption
    @caption = caption
  else
    if (value = @document.attributes['caption'])
      @caption = value
    elsif title?
      key ||= @context.to_s
      caption_key = "#{key}-caption"
      if (caption_title = @document.attributes[caption_key])
        caption_num = @document.counter_increment("#{key}-number", self)
        @caption = "#{caption_title} #{caption_num}. "
      end
    end
  end
  nil
end

def assign_index(section)
  section.index = @next_section_index
  @next_section_index += 1
  if section.sectname == 'appendix'
    appendix_number = @document.counter 'appendix-number', 'A'
    section.number = appendix_number if section.numbered
    if (caption = @document.attr 'appendix-caption', '') != ''
      section.caption = %(#{caption} #{appendix_number}: )
    else
      section.caption = %(#{appendix_number}. )
    end
  elsif section.numbered
    # chapters in a book doctype should be sequential even when divided into parts
    if (section.level == 1 || (section.level == 0 && section.special)) && @document.doctype == 'book'
      section.number = @document.counter('chapter-number', 1)
    else
      section.number = @next_section_number
      @next_section_number += 1
    end
  end
end

def block?
  true
end

def blocks?
  !@blocks.empty?
end

def captioned_title
  %(#{@caption}#{title})
end

def content
  @blocks.map {|b| b.convert } * EOL
end

def context=(context)
  @context = context
  @node_name = context.to_s
end

def convert
  @document.playback_attributes @attributes
  converter.convert self
end

def file
  @source_location ? @source_location.file : nil
end

def find_by selector = {}, &block
  result = []
  if ((any_context = !(context_selector = selector[:context])) || context_selector == @context) &&
      (!(style_selector = selector[:style]) || style_selector == @style) &&
      (!(role_selector = selector[:role]) || has_role?(role_selector)) &&
      (!(id_selector = selector[:id]) || id_selector == @id)
    if id_selector
      return [(block_given? && yield(self) ? self : self)]
    else
      result << (block_given? && yield(self) ? self : self)
    end
  end
  # process document header as a section if present
  if @context == :document && (any_context || context_selector == :section) && header?
    result.concat(@header.find_by(selector, &block) || [])
  end
  # yuck, dlist is a special case
  unless context_selector == :document # optimization
    if @context == :dlist
      if any_context || context_selector != :section # optimization
        @blocks.flatten.each do |li|
          result.concat(li.find_by(selector, &block) || [])
        end
      end
    elsif
      @blocks.each do |b|
        next if (context_selector == :section && b.context != :section) # optimization
        result.concat(b.find_by(selector, &block) || [])
      end
    end
  end
  result.empty? ? nil : result
end

def initialize parent, context, opts = {}
  super
  @content_model = :compound
  @subs = []
  @default_subs = nil
  @blocks = []
  @id = nil
  @title = nil
  @caption = nil
  @style = nil
  @level = if context == :document
    0
  elsif parent && context != :section
    parent.level
  end
  @next_section_index = 0
  @next_section_number = 1
  @source_location = nil
end

def inline?
  false
end

def lineno
  @source_location ? @source_location.lineno : nil
end

def reindex_sections
  @next_section_index = 0
  @next_section_number = 0
  @blocks.each {|block|
    if block.context == :section
      assign_index(block)
      block.reindex_sections
    end
  }
end

def remove_sub sub
  @subs.delete sub
  nil
end

def sections
  @blocks.select {|block| block.context == :section }
end

def sub? name
  @subs.include? name
end

def title
  # prevent substitutions from being applied multiple times
  if defined?(@subbed_title)
    @subbed_title
  elsif @title
    @subbed_title = apply_title_subs(@title)
  else
    @title
  end
end

def title?
  !@title.nil_or_empty?
end