class Kramdown::Parser::Kramdown

# File lib/kramdown/parser/kramdown.rb, line 327
def self.define_parser(name, start_re, span_start = nil, meth_name = "parse_#{name}")
  raise "A parser with the name #{name} already exists!" if @@parsers.key?(name)
  @@parsers[name] = Data.new(name, start_re, span_start, meth_name)
end

# File lib/kramdown/parser/kramdown.rb, line 338
def self.has_parser?(name)
  @@parsers.key?(name)
end

# File lib/kramdown/parser/kramdown.rb, line 333
def self.parser(name = nil)
  @@parsers[name]
end

# File lib/kramdown/parser/kramdown/link.rb, line 38
def add_link(el, href, title, alt_text = nil, ial = nil)
  el.options[:ial] = ial
  update_attr_with_ial(el.attr, ial) if ial
  if el.type == :a
    el.attr['href'] = href
  else
    el.attr['src'] = href
    el.attr['alt'] = alt_text
    el.children.clear
  end
  el.attr['title'] = title if title
  @tree.children << el
end

# File lib/kramdown/parser/kramdown/block_boundary.rb, line 20
def after_block_boundary?
  last_child = @tree.children.last
  !last_child || last_child.type == :blank ||
    (last_child.type == :eob && last_child.value.nil?) || @block_ial
end

# File lib/kramdown/parser/kramdown/block_boundary.rb, line 27
def before_block_boundary?
  @src.check(self.class::BLOCK_BOUNDARY)
end

# File lib/kramdown/parser/kramdown/abbreviation.rb, line 33
def correct_abbreviations_attributes
  @root.options[:abbrev_attr].keys.each do |k|
    @root.options[:abbrev_attr][k] = @root.options[:abbrev_attr][k].attr
  end
end

# File lib/kramdown/parser/kramdown/extensions.rb, line 95
def handle_extension(name, opts, body, type, line_no = nil)
  case name
  when 'comment'
    if body.kind_of?(String)
      @tree.children << Element.new(:comment, body, nil, category: type, location: line_no)
    end
    true
  when 'nomarkdown'
    if body.kind_of?(String)
      @tree.children << Element.new(:raw, body, nil, category: type,
                                    location: line_no, type: opts['type'].to_s.split(/\s+/))
    end
    true
  when 'options'
    opts.select do |k, v|
      k = k.to_sym
      if Kramdown::Options.defined?(k)
        if @options[:forbidden_inline_options].include?(k) ||
            k == :forbidden_inline_options
          warning("Option #{k} may not be set inline")
          next false
        end

        begin
          val = Kramdown::Options.parse(k, v)
          @options[k] = val
          (@root.options[:options] ||= {})[k] = val
        rescue StandardError
        end
        false
      else
        true
      end
    end.each do |k, _v|
      warning("Unknown kramdown option '#{k}'")
    end
    @tree.children << new_block_el(:eob, :extension) if type == :block
    true
  else
    false
  end
end

# File lib/kramdown/parser/kramdown/html.rb, line 24
def handle_kramdown_html_tag(el, closed, handle_body)
  if @block_ial
    el.options[:ial] = @block_ial
    @block_ial = nil
  end

  content_model = if @tree.type != :html_element || @tree.options[:content_model] != :raw
                    (@options[:parse_block_html] ? HTML_CONTENT_MODEL[el.value] : :raw)
                  else
                    :raw
                  end
  if (val = HTML_MARKDOWN_ATTR_MAP[el.attr.delete('markdown')])
    content_model = (val == :default ? HTML_CONTENT_MODEL[el.value] : val)
  end

  @src.scan(TRAILING_WHITESPACE) if content_model == :block
  el.options[:content_model] = content_model
  el.options[:is_closed] = closed

  if !closed && handle_body
    if content_model == :block
      unless parse_blocks(el)
        warning("Found no end tag for '#{el.value}' (line #{el.options[:location]}) - auto-closing it")
      end
    elsif content_model == :span
      curpos = @src.pos
      if @src.scan_until(/(?=<\/#{el.value}\s*>)/mi)
        add_text(extract_string(curpos...@src.pos, @src), el)
        @src.scan(HTML_TAG_CLOSE_RE)
      else
        add_text(@src.rest, el)
        @src.terminate
        warning("Found no end tag for '#{el.value}' (line #{el.options[:location]}) - auto-closing it")
      end
    else
      parse_raw_html(el, &method(:handle_kramdown_html_tag))
    end
    unless @tree.type == :html_element && @tree.options[:content_model] == :raw
      @src.scan(TRAILING_WHITESPACE)
    end
  end
end

# File lib/kramdown/parser/kramdown/link.rb, line 16
def normalize_link_id(id)
  id.gsub(/[\s]+/, ' ').downcase
end

# File lib/kramdown/parser/kramdown/paragraph.rb, line 55
def paragraph_end
  self.class::PARAGRAPH_END
end

# File lib/kramdown/parser/kramdown.rb, line 87
def parse
  configure_parser
  parse_blocks(@root, adapt_source(source))
  update_tree(@root)
  correct_abbreviations_attributes
  replace_abbreviations(@root)
  @footnotes.each do |_name, data|
    update_tree(data[:content])
    replace_abbreviations(data[:content])
  end
  footnote_count = 0
  @footnotes.each do |name, data|
    (footnote_count += 1; next) if data.key?(:marker)
    line = data[:content].options[:location]
    warning("Footnote definition for '#{name}' on line #{line} is unreferenced - ignoring")
  end
  @root.options[:footnote_count] = footnote_count
end

# File lib/kramdown/parser/kramdown/abbreviation.rb, line 16
def parse_abbrev_definition
  start_line_number = @src.current_line_number
  @src.pos += @src.matched_size
  abbrev_id, abbrev_text = @src[1], @src[2]
  abbrev_text.strip!
  if @root.options[:abbrev_defs][abbrev_id]
    warning("Duplicate abbreviation ID '#{abbrev_id}' on line #{start_line_number} " \
            "- overwriting")
  end
  @tree.children << new_block_el(:eob, :abbrev_def)
  @root.options[:abbrev_defs][abbrev_id] = abbrev_text
  @root.options[:abbrev_attr][abbrev_id] = @tree.children.last
  true
end

# File lib/kramdown/parser/kramdown/extensions.rb, line 17
def parse_attribute_list(str, opts)
  return if str.strip.empty? || str.strip == ':'
  attrs = str.scan(ALD_TYPE_ANY)
  attrs.each do |key, sep, val, ref, id_and_or_class, _, _|
    if ref
      (opts[:refs] ||= []) << ref
    elsif id_and_or_class
      id_and_or_class.scan(ALD_TYPE_ID_OR_CLASS).each do |id_attr, class_attr|
        if class_attr
          opts[IAL_CLASS_ATTR] = "#{opts[IAL_CLASS_ATTR]} #{class_attr}".lstrip
        else
          opts['id'] = id_attr
        end
      end
    else
      val.gsub!(/\\(\}|#{sep})/, "\\1")
      opts[key] = val
    end
  end
  warning("No or invalid attributes found in IAL/ALD content: #{str}") if attrs.empty?
end

# File lib/kramdown/parser/kramdown/header.rb, line 31
def parse_atx_header
  return false unless after_block_boundary?
  text, id = parse_header_contents
  text.sub!(/(?<!\\)#+\z/, '') && text.rstrip!
  return false if text.empty?
  add_header(@src["level"].length, text, id)
  true
end

# File lib/kramdown/parser/kramdown/autolink.rb, line 18
def parse_autolink
  start_line_number = @src.current_line_number
  @src.pos += @src.matched_size
  href = (@src[2].nil? ? "mailto:#{@src[1]}" : @src[1])
  el = Element.new(:a, nil, {'href' => href}, location: start_line_number)
  add_text(@src[1].sub(/^mailto:/, ''), el)
  @tree.children << el
end

# File lib/kramdown/parser/kramdown/blank_line.rb, line 16
def parse_blank_line
  @src.pos += @src.matched_size
  if (last_child = @tree.children.last) && last_child.type == :blank
    last_child.value << @src.matched
  else
    @tree.children << new_block_el(:blank, @src.matched)
  end
  true
end

# File lib/kramdown/parser/kramdown/extensions.rb, line 163
def parse_block_extensions
  if @src.scan(ALD_START)
    parse_attribute_list(@src[2], @alds[@src[1]] ||= {})
    @tree.children << new_block_el(:eob, :ald)
    true
  elsif @src.check(EXT_BLOCK_START)
    parse_extension_start_tag(:block)
  elsif @src.scan(IAL_BLOCK_START)
    if (last_child = @tree.children.last) && last_child.type != :blank &&
        (last_child.type != :eob ||
         [:link_def, :abbrev_def, :footnote_def].include?(last_child.value))
      parse_attribute_list(@src[1], last_child.options[:ial] ||= {})
      @tree.children << new_block_el(:eob, :ial) unless @src.check(IAL_BLOCK_START)
    else
      parse_attribute_list(@src[1], @block_ial ||= {})
    end
    true
  else
    false
  end
end

# File lib/kramdown/parser/kramdown/html.rb, line 70
def parse_block_html
  line = @src.current_line_number
  if (result = @src.scan(HTML_COMMENT_RE))
    @tree.children << Element.new(:xml_comment, result, nil, category: :block, location: line)
    @src.scan(TRAILING_WHITESPACE)
    true
  else
    if @src.check(/^#{OPT_SPACE}#{HTML_TAG_RE}/o) && !HTML_SPAN_ELEMENTS.include?(@src[1].downcase)
      @src.pos += @src.matched_size
      handle_html_start_tag(line, &method(:handle_kramdown_html_tag))
      Kramdown::Parser::Html::ElementConverter.convert(@root, @tree.children.last) if @options[:html_to_native]
      true
    elsif @src.check(/^#{OPT_SPACE}#{HTML_TAG_CLOSE_RE}/o) && !HTML_SPAN_ELEMENTS.include?(@src[1].downcase)
      name = @src[1].downcase

      if @tree.type == :html_element && @tree.value == name
        @src.pos += @src.matched_size
        throw :stop_block_parsing, :found
      else
        false
      end
    else
      false
    end
  end
end

# File lib/kramdown/parser/kramdown/math.rb, line 18
def parse_block_math
  start_line_number = @src.current_line_number
  if !after_block_boundary?
    return false
  elsif @src[1]
    @src.scan(/^#{OPT_SPACE}\\/o) if @src[3]
    return false
  end

  saved_pos = @src.save_pos
  @src.pos += @src.matched_size
  data = @src[2].strip
  if before_block_boundary?
    @tree.children << new_block_el(:math, data, nil, category: :block, location: start_line_number)
    true
  else
    @src.revert_pos(saved_pos)
    false
  end
end

# File lib/kramdown/parser/kramdown/blockquote.rb, line 20
def parse_blockquote
  start_line_number = @src.current_line_number
  result = @src.scan(PARAGRAPH_MATCH)
  until @src.match?(self.class::LAZY_END)
    result << @src.scan(PARAGRAPH_MATCH)
  end
  result.gsub!(BLOCKQUOTE_START, '')

  el = new_block_el(:blockquote, nil, nil, location: start_line_number)
  @tree.children << el
  parse_blocks(el, result)
  true
end

# File lib/kramdown/parser/kramdown/codeblock.rb, line 22
def parse_codeblock
  start_line_number = @src.current_line_number
  data = @src.scan(self.class::CODEBLOCK_MATCH)
  data.gsub!(/\n( {0,3}\S)/, ' \\1')
  data.gsub!(INDENT, '')
  @tree.children << new_block_el(:codeblock, data, nil, location: start_line_number)
  true
end

# File lib/kramdown/parser/kramdown/codeblock.rb, line 36
def parse_codeblock_fenced
  if @src.check(self.class::FENCED_CODEBLOCK_MATCH)
    start_line_number = @src.current_line_number
    @src.pos += @src.matched_size
    el = new_block_el(:codeblock, @src[5], nil, location: start_line_number, fenced: true)
    lang = @src[3].to_s.strip
    unless lang.empty?
      el.options[:lang] = lang
      el.attr['class'] = "language-#{@src[4]}"
    end
    @tree.children << el
    true
  else
    false
  end
end

# File lib/kramdown/parser/kramdown/codespan.rb, line 16
def parse_codespan
  start_line_number = @src.current_line_number
  result = @src.scan(CODESPAN_DELIMITER)
  simple = (result.length == 1)
  saved_pos = @src.save_pos

  if simple && @src.pre_match =~ /\s\Z|\A\Z/ && @src.match?(/\s/)
    add_text(result)
    return
  end

  # assign static regex to avoid allocating the same on every instance
  # where +result+ equals a single-backtick. Interpolate otherwise.
  if result == '`'
    scan_pattern = /`/
    str_sub_pattern = /`\Z/
  else
    scan_pattern = /#{result}/
    str_sub_pattern = /#{result}\Z/
  end

  if (text = @src.scan_until(scan_pattern))
    text.sub!(str_sub_pattern, '')
    unless simple
      text = text[1..-1] if text[0..0] == ' '
      text = text[0..-2] if text[-1..-1] == ' '
    end
    @tree.children << Element.new(:codespan, text, nil, {
                                    codespan_delimiter: result,
                                    location: start_line_number
                                  })

  else
    @src.revert_pos(saved_pos)
    add_text(result)
  end
end

# File lib/kramdown/parser/kramdown/list.rb, line 152
def parse_definition_list
  children = @tree.children
  if !children.last || (children.length == 1 && children.last.type != :p) ||
      (children.length >= 2 && children[-1].type != :p &&
       (children[-1].type != :blank || children[-1].value != "\n" || children[-2].type != :p))
    return false
  end

  first_as_para = false
  deflist = new_block_el(:dl)
  para = @tree.children.pop
  if para.type == :blank
    para = @tree.children.pop
    first_as_para = true
  end
  # take location from preceding para which is the first definition term
  deflist.options[:location] = para.options[:location]
  para.children.first.value.split(/\n/).each do |term|
    el = Element.new(:dt, nil, nil, location: @src.current_line_number)
    term.sub!(self.class::LIST_ITEM_IAL) do
      parse_attribute_list($1, el.options[:ial] ||= {})
      ''
    end
    el.options[:raw_text] = term
    el.children << Element.new(:raw_text, term)
    deflist.children << el
  end
  deflist.options[:ial] = para.options[:ial]

  item = nil
  content_re, lazy_re, indent_re = nil
  def_start_re = DEFINITION_LIST_START
  last_is_blank = false
  until @src.eos?
    start_line_number = @src.current_line_number
    if @src.scan(def_start_re)
      item = Element.new(:dd, nil, nil, location: start_line_number)
      item.options[:first_as_para] = first_as_para
      item.value, indentation, content_re, lazy_re, indent_re =
        parse_first_list_line(@src[1].length, @src[2])
      deflist.children << item

      item.value.sub!(self.class::LIST_ITEM_IAL) do |_match|
        parse_attribute_list($1, item.options[:ial] ||= {})
        ''
      end

      def_start_re = fetch_pattern(:dl, indentation)
      first_as_para = false
      last_is_blank = false
    elsif @src.check(EOB_MARKER)
      break
    elsif (result = @src.scan(content_re)) || (!last_is_blank && (result = @src.scan(lazy_re)))
      result.sub!(/^(\t+)/) { " " * ($1 ? 4 * $1.length : 0) }
      result.sub!(indent_re, '')
      item.value << result
      first_as_para = false
      last_is_blank = false
    elsif (result = @src.scan(BLANK_LINE))
      first_as_para = true
      item.value << result
      last_is_blank = true
    else
      break
    end
  end

  last = nil
  deflist.children.each do |it|
    next if it.type == :dt

    parse_blocks(it, it.value)
    it.value = nil
    it_children = it.children
    next if it_children.empty?

    last = (it_children.last.type == :blank ? it_children.pop : nil)

    if it_children.first && it_children.first.type == :p && !it.options.delete(:first_as_para)
      it_children.first.children.first.value << "\n" if it_children.size > 1
      it_children.first.options[:transparent] = true
    end
  end

  children = @tree.children
  if children.length >= 1 && children.last.type == :dl
    children[-1].children.concat(deflist.children)
  elsif children.length >= 2 && children[-1].type == :blank &&
      children[-2].type == :dl
    children.pop
    children[-1].children.concat(deflist.children)
  else
    children << deflist
  end

  children << last if last

  true
end

# File lib/kramdown/parser/kramdown/emphasis.rb, line 16
def parse_emphasis
  start_line_number = @src.current_line_number
  saved_pos = @src.save_pos

  result = @src.scan(EMPHASIS_START)
  element = (result.length == 2 ? :strong : :em)
  type = result[0..0]

  if (type == '_' && @src.pre_match =~ /[[:alpha:]]-?[[:alpha:]]*\z/) || @src.check(/\s/) ||
      @tree.type == element || @stack.any? {|el, _| el.type == element }
    add_text(result)
    return
  end

  sub_parse = lambda do |delim, elem|
    el = Element.new(elem, nil, nil, location: start_line_number)
    stop_re = /#{Regexp.escape(delim)}/
    found = parse_spans(el, stop_re) do
      (@src.pre_match[-1, 1] !~ /\s/) &&
        (elem != :em || !@src.match?(/#{Regexp.escape(delim * 2)}(?!#{Regexp.escape(delim)})/)) &&
        (type != '_' || !@src.match?(/#{Regexp.escape(delim)}[[:alnum:]]/)) && !el.children.empty?
    end
    [found, el, stop_re]
  end

  found, el, stop_re = sub_parse.call(result, element)
  if !found && element == :strong && @tree.type != :em
    @src.revert_pos(saved_pos)
    @src.pos += 1
    found, el, stop_re = sub_parse.call(type, :em)
  end
  if found
    @src.scan(stop_re)
    @tree.children << el
  else
    @src.revert_pos(saved_pos)
    @src.pos += result.length
    add_text(result)
  end
end

# File lib/kramdown/parser/kramdown/eob.rb, line 16
def parse_eob_marker
  @src.pos += @src.matched_size
  @tree.children << new_block_el(:eob)
  true
end

# File lib/kramdown/parser/kramdown/escaped_chars.rb, line 16
def parse_escaped_chars
  @src.pos += @src.matched_size
  add_text(@src[1])
end

# File lib/kramdown/parser/kramdown/extensions.rb, line 53
def parse_extension_start_tag(type)
  saved_pos = @src.save_pos
  start_line_number = @src.current_line_number
  @src.pos += @src.matched_size

  error_block = lambda do |msg|
    warning(msg)
    @src.revert_pos(saved_pos)
    add_text(@src.getch) if type == :span
    false
  end

  if @src[4] || @src.matched == '{:/}'
    name = (@src[4] ? "for '#{@src[4]}' " : '')
    return error_block.call("Invalid extension stop tag #{name} found on line " \
                            "#{start_line_number} - ignoring it")
  end

  ext = @src[1]
  opts = {}
  body = nil
  parse_attribute_list(@src[2] || '', opts)

  unless @src[3]
    stop_re = (type == :block ? /#{EXT_BLOCK_STOP_STR % ext}/ : /#{EXT_STOP_STR % ext}/)
    if (result = @src.scan_until(stop_re))
      body = result.sub!(stop_re, '')
      body.chomp! if type == :block
    else
      return error_block.call("No stop tag for extension '#{ext}' found on line " \
                              "#{start_line_number} - ignoring it")
    end
  end

  if !handle_extension(ext, opts, body, type, start_line_number)
    error_block.call("Invalid extension with name '#{ext}' specified on line " \
                     "#{start_line_number} - ignoring it")
  else
    true
  end
end

# File lib/kramdown/parser/kramdown/list.rb, line 31
def parse_first_list_line(indentation, content)
  if content =~ self.class::LIST_ITEM_IAL_CHECK
    indentation = 4
  else
    while content =~ /^ *\t/
      temp = content.scan(/^ */).first.length + indentation
      content.sub!(/^( *)(\t+)/) { $1 << " " * (4 - (temp % 4) + ($2.length - 1) * 4) }
    end
    indentation += content[/^ */].length
  end
  content.sub!(/^\s*/, '')

  [content, indentation, *PARSE_FIRST_LIST_LINE_REGEXP_CACHE[indentation]]
end

# File lib/kramdown/parser/kramdown/footnote.rb, line 20
def parse_footnote_definition
  start_line_number = @src.current_line_number
  @src.pos += @src.matched_size

  el = Element.new(:footnote_def, nil, nil, location: start_line_number)
  parse_blocks(el, @src[2].gsub(INDENT, ''))
  if @footnotes[@src[1]]
    warning("Duplicate footnote name '#{@src[1]}' on line #{start_line_number} - overwriting")
  end
  @tree.children << new_block_el(:eob, :footnote_def)
  (@footnotes[@src[1]] = {})[:content] = el
  @footnotes[@src[1]][:eob] = @tree.children.last
  true
end

# File lib/kramdown/parser/kramdown/footnote.rb, line 39
def parse_footnote_marker
  start_line_number = @src.current_line_number
  @src.pos += @src.matched_size
  fn_def = @footnotes[@src[1]]
  if fn_def
    if fn_def[:eob]
      update_attr_with_ial(fn_def[:eob].attr, fn_def[:eob].options[:ial] || {})
      fn_def[:attr] = fn_def[:eob].attr
      fn_def[:options] = fn_def[:eob].options
      fn_def.delete(:eob)
    end
    fn_def[:marker] ||= []
    fn_def[:marker].push(Element.new(:footnote, fn_def[:content], fn_def[:attr],
                                     fn_def[:options].merge(name: @src[1], location: start_line_number)))
    @tree.children << fn_def[:marker].last
  else
    warning("Footnote definition for '#{@src[1]}' not found on line #{start_line_number}")
    add_text(@src.matched)
  end
end

# File lib/kramdown/parser/kramdown/horizontal_rule.rb, line 16
def parse_horizontal_rule
  start_line_number = @src.current_line_number
  @src.pos += @src.matched_size
  @tree.children << new_block_el(:hr, nil, nil, location: start_line_number)
  true
end

# File lib/kramdown/parser/kramdown/html_entity.rb, line 16
def parse_html_entity
  start_line_number = @src.current_line_number
  @src.pos += @src.matched_size
  begin
    value = ::Kramdown::Utils::Entities.entity(@src[1] || (@src[2]&.to_i) || @src[3].hex)
    @tree.children << Element.new(:entity, value,
                                  nil, original: @src.matched, location: start_line_number)
  rescue ::Kramdown::Error
    @tree.children << Element.new(:entity, ::Kramdown::Utils::Entities.entity('amp'),
                                  nil, location: start_line_number)
    add_text(@src.matched[1..-1])
  end
end

# File lib/kramdown/parser/kramdown/math.rb, line 43
def parse_inline_math
  start_line_number = @src.current_line_number
  @src.pos += @src.matched_size
  @tree.children << Element.new(:math, @src[1].strip, nil, category: :span, location: start_line_number)
end

# File lib/kramdown/parser/kramdown/line_break.rb, line 16
def parse_line_break
  @tree.children << Element.new(:br, nil, nil, location: @src.current_line_number)
  @src.pos += @src.matched_size
end

# File lib/kramdown/parser/kramdown/link.rb, line 60
def parse_link
  start_line_number = @src.current_line_number
  result = @src.scan(LINK_START)
  cur_pos = @src.pos
  saved_pos = @src.save_pos

  link_type = (result =~ /^!/ ? :img : :a)

  # no nested links allowed
  if link_type == :a && (@tree.type == :img || @tree.type == :a ||
                         @stack.any? {|t, _| t && (t.type == :img || t.type == :a) })
    add_text(result)
    return
  end
  el = Element.new(link_type, nil, nil, location: start_line_number)

  count = 1
  found = parse_spans(el, LINK_BRACKET_STOP_RE) do
    count += (@src[1] ? -1 : 1)
    count - el.children.select {|c| c.type == :img }.size == 0
  end
  unless found
    @src.revert_pos(saved_pos)
    add_text(result)
    return
  end
  alt_text = extract_string(cur_pos...@src.pos, @src).gsub(ESCAPED_CHARS, '\1')
  @src.scan(LINK_BRACKET_STOP_RE)

  # reference style link or no link url
  if @src.scan(LINK_INLINE_ID_RE) || !@src.check(/\(/)
    emit_warning = !@src[1]
    link_id = normalize_link_id(@src[1] || alt_text)
    if @link_defs.key?(link_id)
      link_def = @link_defs[link_id]
      add_link(el, link_def[0], link_def[1], alt_text,
               link_def[2] && link_def[2].options[:ial])
    else
      if emit_warning
        warning("No link definition for link ID '#{link_id}' found on line #{start_line_number}")
      end
      @src.revert_pos(saved_pos)
      add_text(result)
    end
    return
  end

  # link url in parentheses
  if @src.scan(/\(<(.*?)>/)
    link_url = @src[1]
    if @src.scan(/\)/)
      add_link(el, link_url, nil, alt_text)
      return
    end
  else
    link_url = +''
    nr_of_brackets = 0
    while (temp = @src.scan_until(LINK_PAREN_STOP_RE))
      link_url << temp
      if @src[2]
        nr_of_brackets -= 1
        break if nr_of_brackets == 0
      elsif @src[1]
        nr_of_brackets += 1
      else
        break
      end
    end
    link_url = link_url[1..-2]
    link_url.strip!

    if nr_of_brackets == 0
      add_link(el, link_url, nil, alt_text)
      return
    end
  end

  if @src.scan(LINK_INLINE_TITLE_RE)
    add_link(el, link_url, @src[2], alt_text)
  else
    @src.revert_pos(saved_pos)
    add_text(result)
  end
end

# File lib/kramdown/parser/kramdown/link.rb, line 23
def parse_link_definition
  return false if @src[3].to_s =~ /[ \t]+["']/
  @src.pos += @src.matched_size
  link_id, link_url, link_title = normalize_link_id(@src[1]), @src[2] || @src[3], @src[5]
  if @link_defs[link_id]
    warning("Duplicate link ID '#{link_id}' on line #{@src.current_line_number} - overwriting")
  end
  @tree.children << new_block_el(:eob, :link_def)
  @link_defs[link_id] = [link_url, link_title, @tree.children.last]
  true
end

# File lib/kramdown/parser/kramdown/list.rb, line 53
def parse_list
  start_line_number = @src.current_line_number
  type, list_start_re = (@src.check(LIST_START_UL) ? [:ul, LIST_START_UL] : [:ol, LIST_START_OL])
  list = new_block_el(type, nil, nil, location: start_line_number)

  item = nil
  content_re, lazy_re, indent_re = nil
  eob_found = false
  nested_list_found = false
  last_is_blank = false
  until @src.eos?
    start_line_number = @src.current_line_number
    if last_is_blank && @src.check(HR_START)
      break
    elsif @src.scan(EOB_MARKER)
      eob_found = true
      break
    elsif @src.scan(list_start_re)
      list.options[:first_list_marker] ||= @src[1].strip
      item = Element.new(:li, nil, nil, location: start_line_number)
      item.value, indentation, content_re, lazy_re, indent_re =
        parse_first_list_line(@src[1].length, @src[2])
      list.children << item

      item.value.sub!(self.class::LIST_ITEM_IAL) do
        parse_attribute_list($1, item.options[:ial] ||= {})
        ''
      end

      list_start_re = fetch_pattern(type, indentation)
      nested_list_found = (item.value =~ LIST_START)
      last_is_blank = false
      item.value = [item.value]
    elsif (result = @src.scan(content_re)) || (!last_is_blank && (result = @src.scan(lazy_re)))
      result.sub!(/^(\t+)/) { " " * 4 * $1.length }
      indentation_found = result.sub!(indent_re, '')
      if !nested_list_found && indentation_found && result =~ LIST_START
        item.value << +''
        nested_list_found = true
      elsif nested_list_found && !indentation_found && result =~ LIST_START
        result = " " * (indentation + 4) << result
      end
      item.value.last << result
      last_is_blank = false
    elsif (result = @src.scan(BLANK_LINE))
      nested_list_found = true
      last_is_blank = true
      item.value.last << result
    else
      break
    end
  end

  @tree.children << list

  last = nil
  list.children.each do |it|
    temp = Element.new(:temp, nil, nil, location: it.options[:location])

    env = save_env
    location = it.options[:location]
    it.value.each do |val|
      @src = ::Kramdown::Utils::StringScanner.new(val, location)
      parse_blocks(temp)
      location = @src.current_line_number
    end
    restore_env(env)

    it.children = temp.children
    it.value = nil

    it_children = it.children
    next if it_children.empty?

    # Handle the case where an EOB marker is inserted by a block IAL for the first paragraph
    it_children.delete_at(1) if it_children.first.type == :p &&
      it_children.length >= 2 && it_children[1].type == :eob && it_children.first.options[:ial]

    if it_children.first.type == :p &&
        (it_children.length < 2 || it_children[1].type != :blank ||
        (it == list.children.last && it_children.length == 2 && !eob_found)) &&
        (list.children.last != it || list.children.size == 1 ||
        list.children[0..-2].any? {|cit| !cit.children.first || cit.children.first.type != :p || cit.children.first.options[:transparent] })
      it_children.first.children.first.value << "\n" if it_children.size > 1 && it_children[1].type != :blank
      it_children.first.options[:transparent] = true
    end

    last = (it_children.last.type == :blank ? it_children.pop : nil)
  end

  @tree.children << last if !last.nil? && !eob_found

  true
end

# File lib/kramdown/parser/kramdown/paragraph.rb, line 30
def parse_paragraph
  pos = @src.pos
  start_line_number = @src.current_line_number
  result = @src.scan(PARAGRAPH_MATCH)
  until @src.match?(paragraph_end)
    result << @src.scan(PARAGRAPH_MATCH)
  end
  result.rstrip!
  if (last_child = @tree.children.last) && last_child.type == :p
    last_item_in_para = last_child.children.last
    if last_item_in_para && last_item_in_para.type == @text_type
      joiner = (extract_string((pos - 3)...pos, @src) == "  \n" ? "  \n" : "\n")
      last_item_in_para.value << joiner << result
    else
      add_text(result, last_child)
    end
  else
    @tree.children << new_block_el(:p, nil, nil, location: start_line_number)
    result.lstrip!
    add_text(result, @tree.children.last)
  end
  true
end

# File lib/kramdown/parser/kramdown/header.rb, line 19
def parse_setext_header
  return false unless after_block_boundary?
  text, id = parse_header_contents
  return false if text.empty?
  add_header(@src["level"] == '-' ? 2 : 1, text, id)
  true
end

# File lib/kramdown/parser/kramdown/smart_quotes.rb, line 157
def parse_smart_quotes
  start_line_number = @src.current_line_number
  substs = SQ_RULES.find {|reg, _subst| @src.scan(reg) }[1]
  substs.each do |subst|
    if subst.kind_of?(Integer)
      add_text(@src[subst])
    else
      val = SQ_SUBSTS[[subst, @src[subst.to_s[-1, 1].to_i]]] || subst
      @tree.children << Element.new(:smart_quote, val, nil, location: start_line_number)
    end
  end
end

# File lib/kramdown/parser/kramdown/extensions.rb, line 191
def parse_span_extensions
  if @src.check(EXT_SPAN_START)
    parse_extension_start_tag(:span)
  elsif @src.check(IAL_SPAN_START)
    if (last_child = @tree.children.last) && last_child.type != :text
      @src.pos += @src.matched_size
      attr = {}
      parse_attribute_list(@src[1], attr)
      update_ial_with_ial(last_child.options[:ial] ||= {}, attr)
      update_attr_with_ial(last_child.attr, attr)
    else
      warning("Found span IAL after text - ignoring it")
      add_text(@src.getch)
    end
  else
    add_text(@src.getch)
  end
end

# File lib/kramdown/parser/kramdown/html.rb, line 101
def parse_span_html
  line = @src.current_line_number
  if (result = @src.scan(HTML_COMMENT_RE))
    @tree.children << Element.new(:xml_comment, result, nil, category: :span, location: line)
  elsif (result = @src.scan(HTML_TAG_CLOSE_RE))
    warning("Found invalidly used HTML closing tag for '#{@src[1]}' on line #{line}")
    add_text(result)
  elsif (result = @src.scan(HTML_TAG_RE))
    tag_name = @src[1]
    tag_name.downcase! if HTML_ELEMENT[tag_name.downcase]
    if HTML_BLOCK_ELEMENTS.include?(tag_name)
      warning("Found block HTML tag '#{tag_name}' in span-level text on line #{line}")
      add_text(result)
      return
    end

    attrs = parse_html_attributes(@src[2], line, HTML_ELEMENT[tag_name])
    attrs.each_value {|value| value.gsub!(/\n+/, ' ') unless value.empty? }

    do_parsing = if HTML_CONTENT_MODEL[tag_name] == :raw || @tree.options[:content_model] == :raw
                   false
                 else
                   @options[:parse_span_html]
                 end
    if (val = HTML_MARKDOWN_ATTR_MAP[attrs.delete('markdown')])
      if val == :block
        warning("Cannot use block-level parsing in span-level HTML tag (line #{line}) " \
                "- using default mode")
      elsif val == :span
        do_parsing = true
      elsif val == :default
        do_parsing = HTML_CONTENT_MODEL[tag_name] != :raw
      elsif val == :raw
        do_parsing = false
      end
    end

    el = Element.new(:html_element, tag_name, attrs, category: :span, location: line,
                     content_model: (do_parsing ? :span : :raw), is_closed: !!@src[4])
    @tree.children << el
    stop_re = /<\/#{Regexp.escape(tag_name)}\s*>/
    stop_re = Regexp.new(stop_re.source, Regexp::IGNORECASE) if HTML_ELEMENT[tag_name]
    if !@src[4] && !HTML_ELEMENTS_WITHOUT_BODY.include?(el.value)
      if parse_spans(el, stop_re, (do_parsing ? nil : [:span_html]))
        @src.scan(stop_re)
      else
        warning("Found no end tag for '#{el.value}' (line #{line}) - auto-closing it")
        add_text(@src.rest, el)
        @src.terminate
      end
    end
    Kramdown::Parser::Html::ElementConverter.convert(@root, el) if @options[:html_to_native]
  else
    add_text(@src.getch)
  end
end

# File lib/kramdown/parser/kramdown/table.rb, line 24
def parse_table
  return false unless after_block_boundary?

  saved_pos = @src.save_pos
  orig_pos = @src.pos
  table = new_block_el(:table, nil, nil, alignment: [], location: @src.current_line_number)
  leading_pipe = (@src.check(TABLE_LINE) =~ /^\s*\|/)
  @src.scan(TABLE_SEP_LINE)

  rows = []
  has_footer = false
  columns = 0

  add_container = lambda do |type, force|
    if !has_footer || type != :tbody || force
      cont = Element.new(type)
      cont.children, rows = rows, []
      table.children << cont
    end
  end

  until @src.eos?
    break unless @src.check(TABLE_LINE)
    if @src.scan(TABLE_SEP_LINE)
      if rows.empty?
        # nothing to do, ignoring multiple consecutive separator lines
      elsif table.options[:alignment].empty? && !has_footer
        add_container.call(:thead, false)
        table.options[:alignment] = @src[1].scan(TABLE_HSEP_ALIGN).map do |left, right|
          (left.empty? && right.empty? && :default) || (right.empty? && :left) ||
            (left.empty? && :right) || :center
        end
      else # treat as normal separator line
        add_container.call(:tbody, false)
      end
    elsif @src.scan(TABLE_FSEP_LINE)
      add_container.call(:tbody, true) unless rows.empty?
      has_footer = true
    elsif @src.scan(TABLE_ROW_LINE)
      trow = Element.new(:tr)

      # parse possible code spans on the line and correctly split the line into cells
      env = save_env
      cells = []
      @src[1].split(/(<code.*?>.*?<\/code>)/).each_with_index do |str, i|
        if i.odd?
          (cells.empty? ? cells : cells.last) << str
        else
          reset_env(src: Kramdown::Utils::StringScanner.new(str, @src.current_line_number))
          root = Element.new(:root)
          parse_spans(root, nil, [:codespan])

          root.children.each do |c|
            if c.type == :raw_text
              f, *l = c.value.split(/(?<!\\)\|/, -1).map {|t| t.gsub(/\\\|/, '|') }
              (cells.empty? ? cells : cells.last) << f
              cells.concat(l)
            else
              delim = (c.value.scan(/`+/).max || '') + '`'
              tmp = +"#{delim}#{' ' if delim.size > 1}#{c.value}#{' ' if delim.size > 1}#{delim}"
              (cells.empty? ? cells : cells.last) << tmp
            end
          end
        end
      end
      restore_env(env)

      cells.shift if leading_pipe && cells.first.strip.empty?
      cells.pop if cells.last.strip.empty?
      cells.each do |cell_text|
        tcell = Element.new(:td)
        tcell.children << Element.new(:raw_text, cell_text.strip)
        trow.children << tcell
      end
      columns = [columns, cells.length].max
      rows << trow
    else
      break
    end
  end

  unless before_block_boundary?
    @src.revert_pos(saved_pos)
    return false
  end

  # Parse all lines of the table with the code span parser
  env = save_env
  l_src = ::Kramdown::Utils::StringScanner.new(extract_string(orig_pos...(@src.pos - 1), @src),
                                               @src.current_line_number)
  reset_env(src: l_src)
  root = Element.new(:root)
  parse_spans(root, nil, [:codespan, :span_html])
  restore_env(env)

  # Check if each line has at least one unescaped pipe that is not inside a code span/code
  # HTML element
  # Note: It doesn't matter that we parse *all* span HTML elements because the row splitting
  # algorithm above only takes <code> elements into account!
  pipe_on_line = false
  while (c = root.children.shift)
    next unless (lines = c.value)
    lines = lines.split("\n")
    if c.type == :codespan
      if lines.size > 2 || (lines.size == 2 && !pipe_on_line)
        break
      elsif lines.size == 2 && pipe_on_line
        pipe_on_line = false
      end
    else
      break if lines.size > 1 && !pipe_on_line && lines.first !~ /^#{TABLE_PIPE_CHECK}/o
      pipe_on_line = (lines.size > 1 ? false : pipe_on_line) || (lines.last =~ /^#{TABLE_PIPE_CHECK}/o)
    end
  end
  @src.revert_pos(saved_pos) and return false unless pipe_on_line

  add_container.call(has_footer ? :tfoot : :tbody, false) unless rows.empty?

  if table.children.none? {|el| el.type == :tbody }
    warning("Found table without body on line #{table.options[:location]} - ignoring it")
    @src.revert_pos(saved_pos)
    return false
  end

  # adjust all table rows to have equal number of columns, same for alignment defs
  table.children.each do |kind|
    kind.children.each do |row|
      (columns - row.children.length).times do
        row.children << Element.new(:td)
      end
    end
  end
  if table.options[:alignment].length > columns
    table.options[:alignment] = table.options[:alignment][0...columns]
  else
    table.options[:alignment] += [:default] * (columns - table.options[:alignment].length)
  end

  @tree.children << table

  true
end

# File lib/kramdown/parser/kramdown/typographic_symbol.rb, line 21
def parse_typographic_syms
  start_line_number = @src.current_line_number
  @src.pos += @src.matched_size
  val = TYPOGRAPHIC_SYMS_SUBST[@src.matched]
  if val.kind_of?(Symbol)
    @tree.children << Element.new(:typographic_sym, val, nil, location: start_line_number)
  elsif @src.matched == '\\<<'
    @tree.children << Element.new(:entity, ::Kramdown::Utils::Entities.entity('lt'),
                                  nil, location: start_line_number)
    @tree.children << Element.new(:entity, ::Kramdown::Utils::Entities.entity('lt'),
                                  nil, location: start_line_number)
  else
    @tree.children << Element.new(:entity, ::Kramdown::Utils::Entities.entity('gt'),
                                  nil, location: start_line_number)
    @tree.children << Element.new(:entity, ::Kramdown::Utils::Entities.entity('gt'),
                                  nil, location: start_line_number)
  end
end

# File lib/kramdown/parser/kramdown/abbreviation.rb, line 40
def replace_abbreviations(el, regexps = nil)
  return if @root.options[:abbrev_defs].empty?
  unless regexps
    sorted_abbrevs = @root.options[:abbrev_defs].keys.sort {|a, b| b.length <=> a.length }
    regexps = [Regexp.union(*sorted_abbrevs.map {|k| /#{Regexp.escape(k)}/ })]
    regexps << /(?=(?:\W|^)#{regexps.first}(?!\w))/ # regexp should only match on word boundaries
  end
  el.children.map! do |child|
    if child.type == :text && el.options[:content_model] != :raw
      if child.value =~ regexps.first
        result = []
        strscan = Kramdown::Utils::StringScanner.new(child.value, child.options[:location])
        text_lineno = strscan.current_line_number
        while (temp = strscan.scan_until(regexps.last))
          abbr_lineno = strscan.current_line_number
          abbr = strscan.scan(regexps.first) # begin of line case of abbr with \W char as first one
          if abbr.nil?
            temp << strscan.scan(/\W|^/)
            abbr = strscan.scan(regexps.first)
          end
          result << Element.new(:text, temp, nil, location: text_lineno)
          result << Element.new(:abbreviation, abbr, nil, location: abbr_lineno)
          text_lineno = strscan.current_line_number
        end
        result << Element.new(:text, strscan.rest, nil, location: text_lineno)
      else
        child
      end
    else
      replace_abbreviations(child, regexps)
      child
    end
  end.flatten!
end

# File lib/kramdown/parser/kramdown/extensions.rb, line 40
def update_ial_with_ial(ial, opts)
  (ial[:refs] ||= []).concat(opts[:refs]) if opts.key?(:refs)
  opts.each do |k, v|
    if k == IAL_CLASS_ATTR
      ial[k] = "#{ial[k]} #{v}".lstrip
    elsif k.kind_of?(String)
      ial[k] = v
    end
  end
end

# File lib/kramdown/parser/kramdown/header.rb, line 58
def add_header(level, text, id)
  start_line_number = @src.current_line_number
  @src.pos += @src.matched_size
  el = new_block_el(:header, nil, nil, level: level, raw_text: text, location: start_line_number)
  add_text(text, el)
  el.attr['id'] = id if id
  @tree.children << el
end

# File lib/kramdown/parser/kramdown.rb, line 120
def configure_parser
  @parsers = {}
  (@block_parsers + @span_parsers).each do |name|
    if self.class.has_parser?(name)
      @parsers[name] = self.class.parser(name)
    else
      raise Kramdown::Error, "Unknown parser: #{name}"
    end
  end
  @span_start, @span_start_re = span_parser_regexps
end

# File lib/kramdown/parser/kramdown.rb, line 304
def new_block_el(*args)
  el = Element.new(*args)
  if @block_ial
    el.options[:ial] = @block_ial
    @block_ial = nil
  end
  el
end

# File lib/kramdown/parser/kramdown.rb, line 139
def parse_blocks(el, text = nil)
  @stack.push([@tree, @src, @block_ial])
  @tree, @block_ial = el, nil
  @src = (text.nil? ? @src : ::Kramdown::Utils::StringScanner.new(text, el.options[:location]))

  status = catch(:stop_block_parsing) do
    until @src.eos?
      @block_parsers.any? do |name|
        if @src.check(@parsers[name].start_re)
          send(@parsers[name].method)
        else
          false
        end
      end || begin
        warning('Warning: this should not occur - no block parser handled the line')
        add_text(@src.scan(/.*\n/))
      end
    end
  end

  @tree, @src, @block_ial = *@stack.pop
  status
end

# File lib/kramdown/parser/kramdown/header.rb, line 46
def parse_header_contents
  text = @src["contents"]
  text.rstrip!
  id_match = HEADER_ID.match(text)
  if id_match
    id = id_match["id"]
    text = text[0...-id_match[0].length]
    text.rstrip!
  end
  [text, id]
end

# File lib/kramdown/parser/kramdown.rb, line 213
def parse_spans(el, stop_re = nil, parsers = nil, text_type = @text_type)
  @stack.push([@tree, @text_type]) unless @tree.nil?
  @tree, @text_type = el, text_type

  span_start = @span_start
  span_start_re = @span_start_re
  span_start, span_start_re = span_parser_regexps(parsers) if parsers
  parsers ||= @span_parsers

  used_re = (stop_re.nil? ? span_start_re : span_pattern_cache(stop_re, span_start))
  stop_re_found = false
  while !@src.eos? && !stop_re_found
    if (result = @src.scan_until(used_re))
      add_text(result)
      if stop_re && @src.check(stop_re)
        stop_re_found = (block_given? ? yield : true)
      end
      processed = parsers.any? do |name|
        if @src.check(@parsers[name].start_re)
          send(@parsers[name].method)
          true
        else
          false
        end
      end unless stop_re_found
      add_text(@src.getch) if !processed && !stop_re_found
    else
      (add_text(@src.rest); @src.terminate) unless stop_re
      break
    end
  end

  @tree, @text_type = @stack.pop

  stop_re_found
end

# File lib/kramdown/parser/kramdown.rb, line 252
def reset_env(opts = {})
  opts = {text_type: :raw_text, stack: []}.merge(opts)
  @src = opts[:src]
  @tree = opts[:tree]
  @block_ial = opts[:block_ial]
  @stack = opts[:stack]
  @text_type = opts[:text_type]
end

# File lib/kramdown/parser/kramdown.rb, line 267
def restore_env(env)
  @src, @tree, @block_ial, @stack, @text_type = *env
end

# File lib/kramdown/parser/kramdown.rb, line 262
def save_env
  [@src, @tree, @block_ial, @stack, @text_type]
end

# File lib/kramdown/parser/kramdown.rb, line 133
def span_parser_regexps(parsers = @span_parsers)
  span_start = /#{parsers.map {|name| @parsers[name].span_start }.join('|')}/
  [span_start, /(?=#{span_start})/]
end

# File lib/kramdown/parser/kramdown.rb, line 273
def update_attr_with_ial(attr, ial)
  ial[:refs]&.each do |ref|
    update_attr_with_ial(attr, ref) if (ref = @alds[ref])
  end
  ial.each do |k, v|
    if k == IAL_CLASS_ATTR
      attr[k] = "#{attr[k]} #{v}".lstrip
    elsif k.kind_of?(String)
      attr[k] = v
    end
  end
end

# File lib/kramdown/parser/kramdown.rb, line 115
def update_link_definitions(link_defs)
  link_defs.each {|k, v| @link_defs[normalize_link_id(k)] = v }
end

# File lib/kramdown/parser/kramdown.rb, line 287
def update_raw_text(item)
  raw_text = +''

  append_text = lambda do |child|
    if child.type == :text
      raw_text << child.value
    else
      child.children.each {|c| append_text.call(c) }
    end
  end

  append_text.call(item)
  item.options[:raw_text] = raw_text
end

# File lib/kramdown/parser/kramdown.rb, line 165
def update_tree(element)
  last_blank = nil
  element.children.map! do |child|
    if child.type == :raw_text
      last_blank = nil
      reset_env(src: ::Kramdown::Utils::StringScanner.new(child.value, element.options[:location]),
                text_type: :text)
      parse_spans(child)
      child.children
    elsif child.type == :eob
      update_attr_with_ial(child.attr, child.options[:ial]) if child.options[:ial]
      []
    elsif child.type == :blank
      if last_blank
        last_blank.value << child.value
        []
      else
        last_blank = child
        child
      end
    else
      last_blank = nil
      update_tree(child)
      update_attr_with_ial(child.attr, child.options[:ial]) if child.options[:ial]
      # DEPRECATED: option auto_id_stripping will be removed in 2.0 because then this will be
      # the default behaviour
      if child.type == :dt || (child.type == :header && @options[:auto_id_stripping])
        update_raw_text(child)
      end
      child
    end
  end.flatten!
end