# -*- coding: utf-8; -*-
#
# gfm_style.rb: "GitHub Flavored Markdown" (GFM) style for tDiary 2.x format.
#
# if you want to use this style, add @style into tdiary.conf below:
#
#    @style = 'GFM'
#
# Copyright (C) 2003, TADA Tadashi <sho@spc.gr.jp>
# Copyright (C) 2004, MoonWolf <moonwolf@moonwolf.com>
# Copyright (C) 2012, kdmsnr <kdmsnr@gmail.com>
# Copyright (C) 2013, hsbt <shibata.hiroshi@gmail.com>
# You can distribute this under GPL.
#

require 'redcarpet'
require 'pygments'
require 'twitter-text'

class HTMLwithPygments < Redcarpet::Render::HTML
	def block_code(code, language)
		Pygments.highlight(code, :lexer => language)
	rescue Exception
		<<-HTML
<div class="highlight"><pre>#{CGI.escapeHTML(code)}</pre></div>
		HTML
	end
end

module TDiary
	module Style
		class GfmSection
			include BaseSection
			include Twitter::Autolink

			def initialize(fragment, author = nil)
				@author = author
				@subtitle, @body = fragment.split(/\n/, 2)
				@subtitle.sub!(/^\#\s*/,'')
				@body ||= ''

				@categories = get_categories
				@stripped_subtitle = strip_subtitle

				@subtitle_to_html = @subtitle ? to_html('# ' + @subtitle).gsub(/\A<h\d>|<\/h\d>\z/io, '') : nil
				@stripped_subtitle_to_html = @stripped_subtitle ? to_html('# ' + @stripped_subtitle).gsub(/\A<h\d>|<\/h\d>\z/io, '') : nil
				@body_to_html = to_html(@body)
			end

			def subtitle=(subtitle)
				@subtitle = (subtitle || '').sub(/^# /,"\##{categories_to_string} ")
				@strip_subtitle = strip_subtitle
			end

			def categories=(categories)
				@subtitle = "#{categories_to_string} " + (strip_subtitle || '')
				@strip_subtitle = strip_subtitle
			end

			def to_src
				r = ''
				r << "\# #{@subtitle}\n" if @subtitle
				r << @body
			end

			def do_html4(date, idx, opt)
				subtitle = to_html('# ' + @subtitle)
				subtitle.sub!( %r!<h3>(.+?)</h3>!m ) do
					"<h3><%= subtitle_proc( Time.at( #{date.to_i} ), #{$1.dump.gsub( /%/, '\\\\045' )} ) %></h3>"
				end
				if opt['multi_user'] and @author then
					subtitle.sub!(/<\/h3>/,%Q|[#{@author}]</h3>|)
				end
				r = subtitle
				r << @body_to_html
			end

			private

			def to_html(string)
				renderer = HTMLwithPygments.new(:hard_wrap => true)
				extensions = {:fenced_code_blocks => true, :tables => true, :no_intra_emphasis => true}
				r = Redcarpet::Markdown.new(renderer, extensions).render(string)

				# Twitter Autolink
				r = auto_link(r)

				if r =~ /(<pre>|<code>)/
					r.gsub!(/<a class=\"tweet-url username\" href=\".*?\">(.*?)<\/a>/){ $1 }
				end

				# except url autolink in plugin block
				if r =~ /\{\{.+?\}\}/
					r.gsub!(/<a href=\"(.*?)\" rel=\"nofollow\">.*?<\/a>/){ $1 }
					r.gsub!(/\{\{(.+?)\}\}/) { "<%=#{CGI.unescapeHTML($1).gsub(/&#39;/, "'").gsub(/&quot;/, '"')}%>" }
				end

				# ignore duplicate autolink
				if r =~ /<a href="<a href="/
					r.gsub!(/<a href="<a href=".*?" rel="nofollow">(.*?)<\/a>"(.*?)>(.*?)<\/a>/) do
						"<a href=\"#{$1}\" rel=\"nofollow\"#{$2}>#{$3}</a>"
					end
				end
				# ignore auto imagelink
				if r =~ /<img src="<a href="/
					r.gsub!(/<img src="<a href=".*?" rel="nofollow">(.*?)<\/a>"(?: alt="(.*?)")?>/){ "<img src=\"#{$1}\" alt=\"#{$2}\">" }
				end

				# emoji
				r = r.emojify

				# diary anchor
				r.gsub!(/<h(\d)/) { "<h#{$1.to_i + 2}" }
				r.gsub!(/<\/h(\d)/) { "</h#{$1.to_i + 2}" }

				# my syntax
				r.gsub!(/<a href="(\d{4}|\d{6}|\d{8}|\d{8}-\d+)[^\d]*?#?([pct]\d+)?">(.*?)<\/a>/) {
					unless $3.empty?
						%Q|<%=my "#{$1}#{$2}", "#{$3}" %>|
					else
						%Q|<%=my "#{$1}#{$2}", "#{$1}#{$2}" %>|
					end
				}

				r
			end

			def get_categories
				return [] unless @subtitle
				cat = /(\\?\[([^\[]+?)\\?\])+/.match(@subtitle).to_a[0]
				return [] unless cat
				cat.scan(/\\?\[(.*?)\\?\]/).collect do |c|
					c[0].split(/,/)
				end.flatten
			end

			def strip_subtitle
				return nil unless @subtitle
				r = @subtitle.sub(/^((\\?\[[^\[]+?\]\\?)+\s+)?/, '')
				if r.empty?
					nil
				else
					r
				end
			end
		end

		class GfmDiary
			include BaseDiary
			include CategorizableDiary

			def initialize(date, title, body, modified = Time.now)
				init_diary
				replace( date, title, body )
				@last_modified = modified
			end

			def style
				'GFM'
			end

			def append(body, author = nil)
				section = nil
				body.each_line do |l|
					case l
					when /^\#[^\#]/
						@sections << GfmSection.new(section, author) if section
						section = l
					else
						section = '' unless section
						section << l
					end
				end
				if section
					section << "\n" unless section =~ /\n\n\z/
					@sections << GfmSection.new(section, author)
				end
				@last_modified = Time.now
				self
			end

			def add_section(subtitle, body)
				@sections = GfmSection.new("\# #{subtitle}\n\n#{body}")
				@sections.size
			end
		end
	end
end

# Local Variables:
# mode: ruby
# indent-tabs-mode: t
# tab-width: 3
# ruby-indent-level: 3
# End: