# encoding: utf-8
=begin

 * Name: SiSU

 * Description: a framework for document structuring, publishing and search

 * Author: Ralph Amissah

 * Copyright: (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
   2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015 Ralph Amissah,
   All Rights Reserved.

 * License: GPL 3 or later:

   SiSU, a framework for document structuring, publishing and search

   Copyright (C) Ralph Amissah

   This program is free software: you can redistribute it and/or modify it
   under the terms of the GNU General Public License as published by the Free
   Software Foundation, either version 3 of the License, or (at your option)
   any later version.

   This program is distributed in the hope that it will be useful, but WITHOUT
   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
   more details.

   You should have received a copy of the GNU General Public License along with
   this program. If not, see <http://www.gnu.org/licenses/>.

   If you have Internet connection, the latest version of the GPL should be
   available at these locations:
   <http://www.fsf.org/licensing/licenses/gpl.html>
   <http://www.gnu.org/licenses/gpl.html>

   <http://www.sisudoc.org/sisu/en/manifest/gpl.fsf.html>

 * SiSU uses:
   * Standard SiSU markup syntax,
   * Standard SiSU meta-markup syntax, and the
   * Standard SiSU object citation numbering and system

 * Hompages:
   <http://www.jus.uio.no/sisu>
   <http://www.sisudoc.org>

 * Git
   <http://git.sisudoc.org/gitweb/?p=code/sisu.git;a=summary>
   <http://git.sisudoc.org/gitweb/?p=code/sisu.git;a=blob;f=lib/sisu/v5/plaintext_markdown.rb;hb=HEAD>

 * Ralph Amissah
   <ralph@amissah.com>
   <ralph.amissah@gmail.com>

 ** Description: plaintext (smarttext) generation, markdown

=end
module SiSU_Txt_Markdown
  require_relative 'ao'                                 # ao.rb
  require_relative 'se'                                 # se.rb
    include SiSU_Env
  require_relative 'shared_metadata'                    # shared_metadata.rb
  require_relative 'generic_parts'                      # generic_parts.rb
  require_relative 'txt_shared'                         # txt_shared.rb
  include SiSU_Param
  @@alt_id_count,@@alt_id_count,@@tablehead,@@number_of_cols=0,0,0,0
  @@tablefoot=''
  class Source
    def initialize(opt)
      @opt=opt
      unless @opt.fns =~/(.+?)\.(?:-|ssm\.)?sst$/
        puts "#{sf} not a processed file type"
      end
    end
    def read
      begin
        md=SiSU_Param::Parameters.new(@opt).get
        env=SiSU_Env::InfoEnv.new(@opt.fns)
        unless @opt.act[:quiet][:set]==:on
          tool=(@opt.act[:verbose][:set]==:on \
          || @opt.act[:verbose_plus][:set]==:on \
          || @opt.act[:maintenance][:set]==:on) \
          ? "#{env.program.text_editor} #{md.file.output_path.markdown.dir}/#{md.file.base_filename.markdown}"
          : "[#{@opt.f_pth[:lng_is]}] #{@opt.fno}"
          (@opt.act[:verbose][:set]==:on \
          || @opt.act[:verbose_plus][:set]==:on \
          || @opt.act[:maintenance][:set]==:on) \
          ? SiSU_Screen::Ansi.new(
              @opt.act[:color_state][:set],
              'Markdown (plaintext utf-8)',
              tool
            ).green_hi_blue
          : SiSU_Screen::Ansi.new(
              @opt.act[:color_state][:set],
              'Markdown (plaintext utf-8)',
              tool
            ).green_title_hi
          if (@opt.act[:verbose_plus][:set]==:on \
          || @opt.act[:maintenance][:set]==:on)
            SiSU_Screen::Ansi.new(
              @opt.act[:color_state][:set],
              @opt.fns,"#{md.file.output_path.markdown.dir}/#{md.file.base_filename.markdown}"
            ).flow
          end
        end
        ao_array=SiSU_AO::Source.new(@opt).get # ao file drawn here
        wrap_width=if defined? md.make.plaintext_wrap \
        and md.make.plaintext_wrap
          md.make.plaintext_wrap
        elsif defined? env.plaintext_wrap \
        and env.plaintext_wrap
          env.plaintext_wrap
        else 78
        end
        #wrap_width=(defined? md.make.plaintext_wrap) ? md.make.plaintext_wrap : 78
        SiSU_Txt_Markdown::Source::Scroll.new(md,ao_array,wrap_width).songsheet
      rescue
        SiSU_Errors::Rescued.new($!,$@,@opt.selections.str,@opt.fns).location do
          __LINE__.to_s + ':' + __FILE__
        end
      ensure
      end
    end
    private
    class Scroll <Source
      include SiSU_Parts_Generic
      include SiSU_TextUtils
      @@endnotes={ para: [], end: [] }
      def initialize(md,data,wrap_width)
        @md,@data,@wrap_width=md,data,wrap_width
        @env=SiSU_Env::InfoEnv.new(@md.fns)
        @tab="\t"
        @@endnotes_=case md.opt.selections.str
        when /--footnote/ then false
        when /--endnote/  then true
        else                   true
        end
        @plaintext={ body: [], open: [], close: [], head: [], metadata: [], tail: [] }
      end
      def songsheet
        plaintext=markup(@data)
        publish(plaintext)
      end
      def break_line
        "\n"
      end
      # Used for extraction of endnotes from paragraphs
      def extract_endnotes(dob='')
        notes=dob.obj.scan(/(?:#{Mx[:en_a_o]}|#{Mx[:en_b_o]})([\d*+]+\s+.+?)(?:#{Mx[:en_a_c]}|#{Mx[:en_b_c]})/)
        @n=[]
        notes.flatten.each do |n| #high cost to deal with <br> appropriately within plaintext, consider
          n=n.dup.to_s
          if n =~/#{Mx[:br_line]}|#{Mx[:br_nl]}/
            fix = n.split(/#{Mx[:br_line]}|#{Mx[:br_nl]}/) #watch #added
            fix.each do |x|
              unless x.empty?; @n << x
              end
            end
          else                 @n << n
          end
        end
        notes=@n.flatten
        notes.each do |e|
          util=(e.to_s =~/^\[[\d*+]+\]:/) \
          ? (SiSU_TextUtils::Wrap.new(e.to_s,@wrap_width,4,1))
          : (SiSU_TextUtils::Wrap.new(e.to_s,@wrap_width,1,1))
          wrap=util.line_wrap
          wrap=if wrap =~ /^\s*[\d*+]+\s+.+?\s*\Z/m
            wrap.gsub(/^(\s*)([\d*+]+)\s+(.+?)\s*\Z/m, <<-GSUB
\\1[\\2]: \\3
              GSUB
            )
          else
            wrap.gsub(/^(.+)\Z/m, <<-GSUB
\\1
              GSUB
            )
          end
          @@endnotes[:para] << "-#{wrap}"
          @@endnotes[:end] << '' << wrap
        end
        @@endnotes
      end
      def plaintext_metadata
        array=SiSU_Metadata::Summary.new(@md).plaintext.metadata
        array.each do |meta|
          tag,inf=meta.scan(/^.+?:\s|.+/)
          if tag and inf
            util=SiSU_TextUtils::Wrap.new(inf,@wrap_width,15,1)
            txt=util.line_wrap
            @plaintext[:metadata] <<<<WOK

#{@tab}#{tag}#{txt}
WOK
          end
        end
      end
      def plaintext_tail
#       env=SiSU_Env::InfoEnv.new(@md.fns)
        generator="Generated by: #{@md.sisu_version[:project]} #{@md.sisu_version[:version]} of #{@md.sisu_version[:date_stamp]} (#{@md.sisu_version[:date]})"  if @md.sisu_version[:version]
        lastdone="Last Generated on: #{Time.now}"
        rubyv="Ruby version: #{@md.ruby_version}"
        sc=if @md.sc_info
          "Source file:    #{@md.sc_filename}#{break_line}Version number: #{@md.sc_number}#{break_line}Version date:   #{@md.sc_date}#{break_line}"
        else ''
        end
        @plaintext[:tail] <<<<WOK
#{break_line}
plaintext (plain text):
   #{@md.file.output_path.markdown.url}/#{@md.file.base_filename.markdown}#{break_line}
Other versions of this document: #{break_line}
manifest:
   #{@md.file.output_path.manifest.url}/#{@md.file.base_filename.manifest}#{break_line}
at:
   #{@md.file.output_path.base.url}#{break_line}

#{sc}
* #{generator}
* #{rubyv}
* #{lastdone}
* SiSU #{the_url.sisu_txt}
WOK
      end
      def decorate
        def heading
          def inline                   #atx
            def l0
              '#'
            end
            def l1
              '##'
            end
            def l2
              '###'
            end
            def l3
              '####'
            end
            def l4
              '#####'
            end
            def l5
              '######'
            end
            self
          end
          def underscore               #Setext
            def l1
              '='
            end
            def l2
              '-'
            end
            def l3
              ''
            end
            def l4
              ''
            end
            def l5
              ''
            end
            def l6
              ''
            end
            self
          end
          self
        end
        def bold
          def open
            '**'
          end
          def close
            '**'
          end
          self
        end
        def italics
          def open
            '*'
          end
          def close
            '*'
          end
          self
        end
        def underscore
          def open
            '_'
          end
          def close
            '_'
          end
          self
        end
       #def emphasis
       #  def open
       #    ''
       #  end
       #  def close
       #    ''
       #  end
       #  self
       #end
        def cite
          def open
            '"'
          end
          def close
            '"'
          end
          self
        end
        def insert
          def open
            '+'
          end
          def close
            '+'
          end
          self
        end
        def strike
          def open
            '-'
          end
          def close
            '-'
          end
          self
        end
        def superscript
          def open
            '^'
          end
          def close
            '^'
          end
          self
        end
        def subscript
          def open
            '['
          end
          def close
            ']'
          end
          self
        end
        def hilite
          def open
            '**'
          end
          def close
            '**'
          end
          self
        end
        def monospace
          def open
            '`'
          end
          def close
            '`'
          end
          self
        end
        self
      end
      def heading_decorated_inline(dob)
        if dob.is==:heading
          heading_inline = case dob.lc
          when 0 then decorate.heading.inline.l0
          when 1 then decorate.heading.inline.l1
          when 2 then decorate.heading.inline.l2
          when 3 then decorate.heading.inline.l3
          when 4 then decorate.heading.inline.l4
          when 5 then decorate.heading.inline.l5
          when 6 then decorate.heading.inline.l6
          end
          heading_inline + ' ' +  dob.obj + ' ' + heading_inline
        end
      end
      def heading_decorated_underscore(dob,times,p_num)
        if dob.is==:heading
          #times=@wrap_width if times > @wrap_width
          case dob.lc
          when 0 then decorate.heading.underscore.l0*times + p_num << break_line*2
          when 1 then decorate.heading.underscore.l1*times + p_num << break_line*2
          when 2 then decorate.heading.underscore.l2*times + p_num << break_line*2
          when 3 then decorate.heading.underscore.l3*times + p_num << break_line*2
          when 4 then decorate.heading.underscore.l4*times + p_num << break_line*2
          when 5 then decorate.heading.underscore.l5*times + p_num << break_line*2
          when 6 then decorate.heading.underscore.l6*times + p_num << break_line*2
          end
        end
      end
      def plaintext_structure(dob='',p_num='') #% Used to extract the structure of a document
        heading_decoration=:inline #(:inline|:underscore) #switch heading decoration between inline & underscore options
        util=nil
        wrapped=if dob.is==:para \
        || dob.is==:heading
          if dob.is==:heading
            util=(heading_decoration== :inline) \
            ? (SiSU_TextUtils::Wrap.new(heading_decorated_inline(dob),@wrap_width,0))
            : (SiSU_TextUtils::Wrap.new(dob.obj,@wrap_width,0))
          elsif dob.is==:para
            if dob.hang \
            and dob.hang =~/[0-9]/ \
            and dob.indent != dob.hang
              util=SiSU_TextUtils::Wrap.new(dob.obj,@wrap_width,dob.indent.to_i*2,dob.hang.to_i*2)
              #util=SiSU_TextUtils::Wrap.new(dob.obj,@wrap_width,dob.hang.to_i*2,0)
            elsif dob.indent =~/[1-9]/
              util=if dob.bullet_
                SiSU_TextUtils::Wrap.new("* #{dob.obj}",@wrap_width,dob.indent.to_i*2)
              else SiSU_TextUtils::Wrap.new(dob.obj,@wrap_width,dob.indent.to_i*2)
              end
            else
              util=if dob.bullet_
                SiSU_TextUtils::Wrap.new("* #{dob.obj}",@wrap_width,0)
              else SiSU_TextUtils::Wrap.new(dob.obj,@wrap_width,0)
              end
            end
          else util=SiSU_TextUtils::Wrap.new(dob.obj,@wrap_width,0)
          end
          dob.is==:heading ? util.no_wrap_no_breaks : util.line_wrap
        end
        if heading_decoration== :underscore \
        and dob.is==:heading
          @plaintext[:body] << wrapped + p_num # main text, contents, body KEEP
          @plaintext[:body] << heading_decorated_underscore(dob,wrapped.length,p_num)
        else
          @plaintext[:body] << wrapped + p_num << break_line # main text, contents, body KEEP
        end
        if @@endnotes[:para] \
        and not @@endnotes_
          @@endnotes[:para].each {|e| @plaintext[:body] << e << break_line}
        elsif @@endnotes[:para] \
        and @@endnotes_
        end
        @@endnotes[:para]=[]
      end
      def markup(data)                                                       # Used for major markup instructions
        SiSU_Env::InfoEnv.new(@md.fns)
        @data_mod,@endnotes,@level,@cont,@copen,@plaintext_contents_close=Array.new(6){[]}
        (0..6).each { |x| @cont[x]=@level[x]=false }
        (4..6).each { |x| @plaintext_contents_close[x]='' }
        plaintext_tail #($1,$2)
        plaintext_metadata
        table_message='[table conversion awaited, see other document formats]'
        data.each do |dob|
          dob.obj=dob.obj.gsub(/#{Mx[:gr_o]}Th?#{Mx[:tc_p]}.+/um,"#{break_line}#{table_message}"). #fix
            gsub(/.+?#{Mx[:gl_o]}-##{Mx[:gl_c]}/,'').                              # remove dummy headings (used by html) #check also [~-]#
            gsub(/#{Mx[:fa_bold_o]}(.+?)#{Mx[:fa_bold_c]}/,
              "#{decorate.bold.open}\\1#{decorate.bold.close}").
            gsub(/#{Mx[:fa_italics_o]}(.+?)#{Mx[:fa_italics_c]}/,
              "#{decorate.italics.open}\\1#{decorate.italics.close}").
            gsub(/#{Mx[:fa_underscore_o]}(.+?)#{Mx[:fa_underscore_c]}/,
              "#{decorate.underscore.open}\\1#{decorate.underscore.close}").
            gsub(/#{Mx[:fa_subscript_o]}(.+?)#{Mx[:fa_subscript_c]}/,
              "#{decorate.subscript.open}\\1#{decorate.subscript.close}").
            gsub(/#{Mx[:fa_superscript_o]}(.+?)#{Mx[:fa_superscript_c]}/,
              "#{decorate.superscript.open}\\1#{decorate.superscript.close}").
            gsub(/#{Mx[:fa_insert_o]}(.+?)#{Mx[:fa_insert_c]}/,
              "#{decorate.insert.open}\\1#{decorate.insert.close}").
            gsub(/#{Mx[:fa_cite_o]}(.+?)#{Mx[:fa_cite_c]}/,
              "#{decorate.cite.open}\\1#{decorate.cite.close}").
            gsub(/#{Mx[:fa_strike_o]}(.+?)#{Mx[:fa_strike_c]}/,
              "#{decorate.strike.open}\\1#{decorate.strike.close}").
            gsub(/#{Mx[:fa_monospace_o]}(.+?)#{Mx[:fa_monospace_c]}/,
              "#{decorate.monospace.open}\\1#{decorate.monospace.close}")
          unless dob.is==:code
            dob.obj=dob.obj.gsub(/#{Mx[:lnk_o]}(.+?)#{Mx[:lnk_c]}#{Mx[:rel_o]}\S+?#{Mx[:rel_c]}/,'\1').
              gsub(/#{Mx[:url_o]}_(\S+?)#{Mx[:url_c]}/,'\1').
              gsub(/#{Mx[:lnk_o]}(.+?)#{Mx[:lnk_c]}#{Mx[:url_o]}(\S+?)#{Mx[:url_c]}/,'\1 [link: <\2>]').
              gsub(/#{Mx[:lnk_o]}(.+?)#{Mx[:lnk_c]}image/,'\1 [link: local image]').
              gsub(/#{Mx[:url_o]}(\S+?)#{Mx[:url_c]}/,"#{the_text.url_open}\\1#{the_text.url_close}")
            extract_endnotes(dob)
            dob.obj=dob.obj.gsub(/#{Mx[:en_a_o]}([\d*+]+)\s+(?:.+?)#{Mx[:en_a_c]}/,'[^\1]'). # endnote marker marked up
              gsub(/#{Mx[:en_b_o]}([\d*+]+)\s+(?:.+?)#{Mx[:en_b_c]}/,'[^\1]'). # endnote marker marked up
              gsub(/#{Mx[:gl_o]}(?:#lt|#060)#{Mx[:gl_c]}/,'<').
              gsub(/#{Mx[:gl_o]}(?:#gt|#062)#{Mx[:gl_c]}/,'>').
              gsub(/#{Mx[:gl_o]}#(?:038|amp)#{Mx[:gl_c]}/,'&').
              gsub(/#{Mx[:gl_o]}#033#{Mx[:gl_c]}/,'!').
              gsub(/#{Mx[:gl_o]}#035#{Mx[:gl_c]}/,'#').
              gsub(/#{Mx[:gl_o]}#042#{Mx[:gl_c]}/,'*').
              gsub(/#{Mx[:gl_o]}#045#{Mx[:gl_c]}/,'-').
              gsub(/#{Mx[:gl_o]}#047#{Mx[:gl_c]}/,'/').
              gsub(/#{Mx[:gl_o]}#095#{Mx[:gl_c]}/,'_').
              gsub(/#{Mx[:gl_o]}#123#{Mx[:gl_c]}/,'{').
              gsub(/#{Mx[:gl_o]}#125#{Mx[:gl_c]}/,'}').
              gsub(/#{Mx[:gl_o]}#126#{Mx[:gl_c]}/,'~').
              gsub(/#{Mx[:gl_o]}#169#{Mx[:gl_c]}/,'©').
              gsub(/#{Mx[:gl_o]}#092#{Mx[:gl_c]}/,'\\')
          end
          dob.obj=if dob.of==:block                                   # watch
            dob.obj.gsub(/#{Mx[:gl_o]}●#{Mx[:gl_c]}/m,"* ").
              gsub(/\n?#{Mx[:br_line]}\n?|\n?#{Mx[:br_nl]}\n?/m,break_line)
          else dob.obj.gsub(/\n?#{Mx[:br_line]}\n?|\n?#{Mx[:br_nl]}\n?/m,break_line*2)
          end
          if dob.is==:code
            dob.obj=dob.obj.gsub(/(^|[^}])_([<>])/m,'\1\2'). # _> _<
              gsub(/(^|[^}])_([<>])/m,'\1\2') # _<_<
          end
          dob.obj=dob.obj.gsub(/#{Mx[:url_o]}_(\S+?)#{Mx[:url_c]}/,'\1').
            gsub(/<a href=".+?">(.+?)<\/a>/m,'\1').
            gsub(/#{Mx[:mk_o]}:name#(\S+?)#{Mx[:mk_c]}/,'').                       # remove name links
            gsub(/&nbsp;|#{Mx[:nbsp]}/,' ').                                       # decide on
            gsub(/(?:^|[^_\\])#{Mx[:lnk_o]}(\S+?\.(?:png|jpg|gif)) .+?#{Mx[:lnk_c]}#{Mx[:url_o]}\S+?#{Mx[:url_c]}/,'    [ \1 ]'). #"[ #{dir.url.images_local}\/\\1 ]")
            gsub(/(?:^|[^_\\])#{Mx[:lnk_o]}(\S+?\.(?:png|jpg|gif)) .+?#{Mx[:lnk_c]}image/,'    [ \1 ]').
            gsub(/(?:^|[^_\\])\{\s*\S+?\.(?:png|jpg|gif)\s+.+?"(.*?)"\s*\}\S+/,'[image: "\1"]')
          if dob.obj !~/(^#{Rx[:meta]}|#{Mx[:br_eof]}|#{Mx[:br_endnotes]})/
            p_num=''
            #ocn
            if dob.is==:heading \
            or dob.is==:para
              plaintext_structure(dob,p_num)
            elsif dob.is==:group \
            or dob.is==:block \
            or dob.is==:verse \
            or dob.is==:code \
            or dob.is==:table
              @plaintext[:body] << dob.obj + p_num << break_line
            elsif dob.is==:break
              sp=' '
              ln='-'
              @plaintext[:body] <<=if dob.obj==Mx[:br_page] \
              or dob.obj==Mx[:br_page_new] \
              or dob.obj==Mx[:br_page_line]
                "#{break_line}#{ln*40}#{break_line*2}"
              elsif dob.obj ==Mx[:br_obj]
                "#{break_line}#{sp*20}*  *  *#{break_line*2}"
              end # following empty line (break_line) missing, fix
            end
            dob='' if (dob.obj =~/<a name="n\d+">/ \
              and dob.obj =~/^(-\{{2}~\d+|<!e[:_]\d+!>)/) # -endnote
            if dob ## Clean Prepared Text
              dob.obj=dob.obj.gsub(/<!.+!>/,' ').
                gsub(/<:\S+>/,' ')
            end
          end
        end
        @plaintext
      end
      def publish(plaintext)
        divider='='
        content=[]
        content << plaintext[:open]
        content << plaintext[:head]
        content << plaintext[:body]
        content << @@endnotes[:end] if @@endnotes_
        content << "#{break_line}#{divider*@wrap_width}#{break_line}"
        content << plaintext[:metadata]
        content << "#{break_line}#{divider*@wrap_width}#{break_line}" if @md.stmp =~/\w+/ #not used?
        content << plaintext[:tail]
        Output.new(content,@md).markdown
        @@endnotes={ para: [], end: [] }
      end
    end
    class Output <Source
      include SiSU_Param
      include SiSU_Env
      def initialize(content,md)
        @content,@md=content,md
      end
      def markdown
        file_plaintext=SiSU_Env::FileOp.new(@md).write_file.markdown
        @sisu=[]
        emptyline=0
        @content.each do |para|                                                # this is a hack
          if para.is_a?(Array) \
          and para.length > 0
            para.each do |line|
              if line
                line=line.gsub(/[ \t]+$/m,'').
                  gsub(/^\A[ ]*\Z/m,'')
                (line=~/^\A\Z/) \
                ? (emptyline+=1)
                : emptyline=0
                if emptyline < 2                     #remove additional empty lines
                  file_plaintext.puts line
                end
              end
            end
          else file_plaintext.puts para          #unix plaintext # /^([*=-]|\.){5}/
          end
        end
        file_plaintext.close
      end
    end
  end
end
__END__