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|
# -*- coding: utf-8; frozen_string_literal: true -*-
#
#--
# Copyright (C) 2009-2026 Thomas Leitner <t_leitner@gmx.at>
#
# This file is part of kramdown which is licensed under the MIT.
#++
#
require 'kramdown/converter'
require 'kramdown/utils'
module Kramdown
module Converter
# Converts an element tree to the kramdown format.
class Kramdown < Base
# :stopdoc:
include ::Kramdown::Utils::Html
def initialize(root, options)
super
@linkrefs = []
@footnotes = []
@abbrevs = []
@stack = []
@list_indent = @options[:list_indent]
@list_spacing = ' ' * (@list_indent - 2)
end
def convert(el, opts = {indent: 0})
res = send("convert_#{el.type}", el, opts)
res = res.dup if res.frozen?
if ![:html_element, :li, :dt, :dd, :td].include?(el.type) && (ial = ial_for_element(el))
res << ial
res << "\n\n" if el.block?
elsif [:ul, :dl, :ol, :codeblock].include?(el.type) && opts[:next] &&
([el.type, :codeblock].include?(opts[:next].type) ||
(opts[:next].type == :blank && opts[:nnext] &&
[el.type, :codeblock].include?(opts[:nnext].type)))
res << "^\n\n"
elsif el.block? &&
![:li, :dd, :dt, :td, :th, :tr, :thead, :tbody, :tfoot, :blank].include?(el.type) &&
(el.type != :html_element || @stack.last.type != :html_element) &&
(el.type != :p || !el.options[:transparent]) &&
!([:ul, :dl, :ol].include?(el.type) && @stack.last.type == :li)
res << "\n"
end
res
end
def inner(el, opts = {indent: 0})
@stack.push(el)
result = +''
el.children.each_with_index do |inner_el, index|
options = opts.dup
options[:index] = index
options[:prev] = (index == 0 ? nil : el.children[index - 1])
options[:pprev] = (index <= 1 ? nil : el.children[index - 2])
options[:next] = (index == el.children.length - 1 ? nil : el.children[index + 1])
options[:nnext] = (index >= el.children.length - 2 ? nil : el.children[index + 2])
result << convert(inner_el, options)
end
@stack.pop
result
end
def convert_blank(_el, _opts)
""
end
ESCAPED_CHAR_RE = /(\$\$|[\\*_`\[\]{"'|])|^ {0,3}(:)/
def convert_text(el, opts)
if opts[:raw_text] || (@stack.last.type == :html_element && @stack.last.options[:content_model] == :raw)
el.value
else
result = el.value.gsub(/\A\n/) do
opts[:prev] && opts[:prev].type == :br ? '' : "\n"
end
result.gsub!(/\s+/, ' ') unless el.options[:cdata]
result.gsub!(ESCAPED_CHAR_RE) do
$1 || !opts[:prev] || opts[:prev].type == :br ? "\\#{$1 || $2}" : $&
end
result
end
end
def convert_p(el, opts)
w = @options[:line_width] - opts[:indent].to_s.to_i
first, second, *rest = inner(el, opts).strip.gsub(/(.{1,#{w}})( +|$\n?)/, "\\1\n").split(/\n/)
first&.gsub!(/^(?:(#|>)|(\d+)\.(\s)|([+-]\s))/) { $1 || $4 ? "\\#{$1 || $4}" : "#{$2}\\.#{$3}" }
second&.gsub!(/^([=-]+\s*?)$/, "\\\1")
res = [first, second, *rest].compact.join("\n") + "\n"
res.gsub!(/^ {0,3}:/, "\\:")
if el.children.length == 1 && el.children.first.type == :math
res = "\\#{res}"
elsif res.start_with?('\$$') && res.end_with?("\\$$\n")
res.sub!(/^\\\$\$/, '\$\$')
end
res
end
def convert_codeblock(el, _opts)
el.value.split("\n").map {|l| l.empty? ? " " : " #{l}" }.join("\n") + "\n"
end
def convert_blockquote(el, opts)
opts[:indent] += 2
inner(el, opts).chomp.split("\n").map {|l| "> #{l}" }.join("\n") << "\n"
end
def convert_header(el, opts)
opts[:in_header] = true
res = +''
res << "#{'#' * output_header_level(el.options[:level])} #{inner(el, opts)}"
res[-1, 1] = "\\#" if res[-1] == '#'
res << " {##{el.attr['id']}}" if el.attr['id'] && !el.attr['id'].strip.empty?
res << "\n"
end
def convert_hr(_el, _opts)
"* * *\n"
end
def convert_ul(el, opts)
inner(el, opts).sub(/\n+\Z/, "\n")
end
alias convert_ol convert_ul
alias convert_dl convert_ul
def convert_li(el, opts)
sym, width = if @stack.last.type == :ul
['* ' + @list_spacing, el.children.first && el.children.first.type == :codeblock ? 4 : @list_indent]
else
["#{opts[:index] + 1}.".ljust(4), 4]
end
if (ial = ial_for_element(el))
sym << ial << " "
end
opts[:indent] += width
text = inner(el, opts)
newlines = text.scan(/\n*\Z/).first
first, *last = text.split("\n")
last = last.map {|l| " " * width + l }.join("\n")
text = (first.nil? ? "\n" : first + (last.empty? ? "" : "\n") + last + newlines)
if el.children.first && el.children.first.type == :p && !el.children.first.options[:transparent]
res = +"#{sym}#{text}"
res << "^\n" if el.children.size == 1 && @stack.last.children.last == el &&
(@stack.last.children.any? {|c| !c.children.first || c.children.first.type != :p } || @stack.last.children.size == 1)
res
elsif el.children.first && el.children.first.type == :codeblock
"#{sym}\n #{text}"
else
"#{sym}#{text}"
end
end
def convert_dd(el, opts)
sym, width = ": " + @list_spacing, (el.children.first && el.children.first.type == :codeblock ? 4 : @list_indent)
if (ial = ial_for_element(el))
sym << ial << " "
end
opts[:indent] += width
text = inner(el, opts)
newlines = text.scan(/\n*\Z/).first
first, *last = text.split("\n")
last = last.map {|l| " " * width + l }.join("\n")
text = first.to_s + (last.empty? ? "" : "\n") + last + newlines
text.chomp! if text =~ /\n\n\Z/ && opts[:next] && opts[:next].type == :dd
text << "\n" if text !~ /\n\n\Z/ && opts[:next] && opts[:next].type == :dt
text << "\n" if el.children.empty?
if el.children.first && el.children.first.type == :p && !el.children.first.options[:transparent]
"\n#{sym}#{text}"
elsif el.children.first && el.children.first.type == :codeblock
"#{sym}\n #{text}"
else
"#{sym}#{text}"
end
end
def convert_dt(el, opts)
result = +''
if (ial = ial_for_element(el))
result << ial << " "
end
result << inner(el, opts) << "\n"
end
HTML_TAGS_WITH_BODY = %w[div script iframe textarea th td]
HTML_ELEMENT_TYPES = [:entity, :text, :html_element].freeze
private_constant :HTML_ELEMENT_TYPES
def convert_html_element(el, opts)
markdown_attr = el.options[:category] == :block && el.children.any? do |c|
c.type != :html_element &&
(c.type != :p || !c.options[:transparent] ||
c.children.any? {|t| !HTML_ELEMENT_TYPES.member?(t.type) }) &&
c.block?
end
opts[:force_raw_text] = true if %w[script pre code].include?(el.value)
opts[:raw_text] = opts[:force_raw_text] || opts[:block_raw_text] || \
(el.options[:category] != :span && !markdown_attr)
opts[:block_raw_text] = true if el.options[:category] == :block && opts[:raw_text]
res = inner(el, opts)
if el.options[:category] == :span
"<#{el.value}#{html_attributes(el.attr)}" + \
(!res.empty? || HTML_TAGS_WITH_BODY.include?(el.value) ? ">#{res}</#{el.value}>" : " />")
else
output = +''
attr = el.attr.dup
attr['markdown'] = '1' if markdown_attr
output << "<#{el.value}#{html_attributes(attr)}"
if !res.empty? && el.options[:content_model] != :block
output << ">#{res}</#{el.value}>"
elsif !res.empty?
output << ">\n#{res}" << "</#{el.value}>"
elsif HTML_TAGS_WITH_BODY.include?(el.value)
output << "></#{el.value}>"
else
output << " />"
end
output << "\n" if @stack.last.type != :html_element || @stack.last.options[:content_model] != :raw
output
end
end
def convert_xml_comment(el, _opts)
if el.options[:category] == :block &&
(@stack.last.type != :html_element || @stack.last.options[:content_model] != :raw)
el.value + "\n"
else
el.value.dup
end
end
alias convert_xml_pi convert_xml_comment
def convert_table(el, opts)
opts[:alignment] = el.options[:alignment]
inner(el, opts)
end
def convert_thead(el, opts)
rows = inner(el, opts)
if opts[:alignment].all?(:default)
"#{rows}|#{'-' * 10}\n"
else
"#{rows}| " + opts[:alignment].map do |a|
case a
when :left then ":-"
when :right then "-:"
when :center then ":-:"
when :default then "-"
end
end.join(' ') << "\n"
end
end
def convert_tbody(el, opts)
res = +''
res << inner(el, opts)
res << '|' << '-' * 10 << "\n" if opts[:next] && opts[:next].type == :tbody
res
end
def convert_tfoot(el, opts)
"|#{'=' * 10}\n#{inner(el, opts)}"
end
def convert_tr(el, opts)
"| #{el.children.map {|c| convert(c, opts) }.join(' | ')} |\n"
end
def convert_td(el, opts)
inner(el, opts)
end
def convert_comment(el, _opts)
if el.options[:category] == :block
"{::comment}\n#{el.value}\n{:/}\n"
else
"{::comment}#{el.value}{:/}"
end
end
def convert_br(_el, opts)
opts[:in_header] ? "<br />" : " \n"
end
def convert_a(el, opts)
if el.attr['href'].empty?
"[#{inner(el, opts)}]()"
elsif el.attr['href'] =~ /^(?:http|ftp)/ || el.attr['href'].count("()") > 0
index = if (link_el = @linkrefs.find {|c| c.attr['href'] == el.attr['href'] })
@linkrefs.index(link_el) + 1
else
@linkrefs << el
@linkrefs.size
end
"[#{inner(el, opts)}][#{index}]"
else
title = parse_title(el.attr['title'])
"[#{inner(el, opts)}](#{el.attr['href']}#{title})"
end
end
def convert_img(el, _opts)
alt_text = el.attr['alt'].to_s.gsub(ESCAPED_CHAR_RE) { $1 ? "\\#{$1}" : $2 }
src = el.attr['src'].to_s
if src.empty?
"![#{alt_text}]()"
else
title = parse_title(el.attr['title'])
link = if src.count("()") > 0
"<#{src}>"
else
src
end
""
end
end
def convert_codespan(el, _opts)
delim = (el.value.scan(/`+/).max || '') + '`'
"#{delim}#{' ' if delim.size > 1}#{el.value}#{' ' if delim.size > 1}#{delim}"
end
def convert_footnote(el, _opts)
@footnotes << [el.options[:name], el.value]
"[^#{el.options[:name]}]"
end
def convert_raw(el, _opts)
attr = (el.options[:type] || []).join(' ')
attr = " type=\"#{attr}\"" unless attr.empty?
if @stack.last.type == :html_element
el.value
elsif el.options[:category] == :block
"{::nomarkdown#{attr}}\n#{el.value}\n{:/}\n"
else
"{::nomarkdown#{attr}}#{el.value}{:/}"
end
end
def convert_em(el, opts)
"*#{inner(el, opts)}*" +
(opts[:next] && [:em, :strong].include?(opts[:next].type) && !ial_for_element(el) ? '{::}' : '')
end
def convert_strong(el, opts)
"**#{inner(el, opts)}**" +
(opts[:next] && [:em, :strong].include?(opts[:next].type) && !ial_for_element(el) ? '{::}' : '')
end
def convert_entity(el, _opts)
entity_to_str(el.value, el.options[:original])
end
TYPOGRAPHIC_SYMS = {
mdash: '---', ndash: '--', hellip: '...',
laquo_space: '<< ', raquo_space: ' >>',
laquo: '<<', raquo: '>>'
}
def convert_typographic_sym(el, _opts)
TYPOGRAPHIC_SYMS[el.value]
end
def convert_smart_quote(el, _opts)
el.value.to_s.match?(/[rl]dquo/) ? "\"" : "'"
end
def convert_math(el, _opts)
"$$#{el.value}$$" + (el.options[:category] == :block ? "\n" : '')
end
def convert_abbreviation(el, _opts)
el.value
end
def convert_root(el, opts)
res = inner(el, opts)
res << create_link_defs
res << create_footnote_defs
res << create_abbrev_defs
res
end
def create_link_defs
res = +''
res << "\n\n" unless @linkrefs.empty?
@linkrefs.each_with_index do |el, i|
title = parse_title(el.attr['title'])
res << "[#{i + 1}]: #{el.attr['href']}#{title}\n"
end
res
end
def create_footnote_defs
res = +''
@footnotes.each do |name, data|
res << "[^#{name}]:\n"
res << inner(data).chomp.split("\n").map {|l| " #{l}" }.join("\n") + "\n\n"
end
res
end
def create_abbrev_defs
return '' unless @root.options[:abbrev_defs]
res = +''
@root.options[:abbrev_defs].each do |name, text|
res << "*[#{name}]: #{text}\n"
res << ial_for_element(Element.new(:unused, nil, @root.options[:abbrev_attr][name])).to_s << "\n\n"
end
res
end
# Return the IAL containing the attributes of the element +el+.
def ial_for_element(el)
res = el.attr.map do |k, v|
next if [:img, :a].include?(el.type) && ['href', 'src', 'alt', 'title'].include?(k)
next if el.type == :header && k == 'id' && !v.strip.empty?
if v.nil?
''
elsif k == 'class' && !v.empty? && !v.index(/[.#]/)
" " + v.split(/\s+/).map {|w| ".#{w}" }.join(" ")
elsif k == 'id' && !v.strip.empty?
" ##{v}"
else
" #{k}=\"#{v}\""
end
end.compact.join
res = "toc" + (res.strip.empty? ? '' : " #{res}") if (el.type == :ul || el.type == :ol) &&
el.options.dig(:ial, :refs)&.include?('toc')
res = "footnotes" + (res.strip.empty? ? '' : " #{res}") if (el.type == :ul || el.type == :ol) &&
el.options.dig(:ial, :refs)&.include?('footnotes')
if el.type == :dl && el.options[:ial] && el.options[:ial][:refs]
auto_ids = el.options[:ial][:refs].select {|ref| ref.start_with?('auto_ids') }.join(" ")
res = auto_ids << (res.strip.empty? ? '' : " #{res}") unless auto_ids.empty?
end
res.strip.empty? ? nil : "{:#{res}}"
end
def parse_title(attr)
attr.to_s.empty? ? '' : ' "' + attr.gsub(/"/, '"') + '"'
end
# :startdoc:
end
end
end
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