# encoding: UTF-8
module Publishr
  class HtmlProcessor
    def initialize(markup='',inpath='',metadata={},rails_resources_url='')
      @markup = markup
      @lines = markup.split("\n")
      @line = ''
      @inpath = inpath
      @metadata = metadata
      @rails_resources_url = rails_resources_url

      @custom_fixes = File.open(File.join(@inpath,'html_postprocessing.rb'), 'r').read if File.exists?(File.join(@inpath,'html_postprocessing.rb'))

      @depth = 0
      @quotetype = nil
      @add_footnote = false
      @process_footnotes = false
      @footnote_number = 0
      @footnote_reference = ''
    end

    def self.sanitize(html)
      Sanitize.clean(html, :elements => ['b','i','em','strong','code','br','var','p','blockquote','img','span'], :attributes => { 'img' => ['src', 'alt'] })
    end

    def degrade
      processed_lines = []
      @lines.each do |l|
        @line = l
        process_line
        processed_lines << @line
      end
      processed_lines.join("\n")
    end

    def process_line
      @process_footnotes = true if @line.include?('<div class="footnotes">')
      @process_footnotes = false if @process_footnotes == true and @line.include?('</div>')
      @add_footnote = true and @footnote_number += 1 if @line.include?('<li id="fn')

      eval(@custom_fixes, binding) if @custom_fixes

      annotate_blockquote
      improve_typography
      make_uppercase
      change_footnote_references
      mark_merge_conflicts
      change_resources_url_for_rails unless @rails_resources_url.to_s.empty?
      process_footnotes if @process_footnotes == true
      add_footnote if @add_footnote == true and @line.include?('<p>')
      make_footnote_paragraph if @process_footnotes == true and @line.include?('<p')
    end

    def improve_typography
      @line.gsub!(/title\((.*?)\)/,'<cite>\1</cite>')
      @line.gsub!(/name\((.*?)\)/,'<var>\1</var>')
      @line.gsub!(/(\(\w\))/,'<i>\1</i>')
    end


    # Kindle doesn't recognize <blockquote>, so add class to p tags depending on the blockquote depth
    def annotate_blockquote
      if @line.include?('<blockquote')
        @depth += 1
        @quotetype = /<blockquote class="(.*?)">/.match(@line) if @depth == 1
      end
      if @line.include?('</blockquote')
        @depth -= 1
        @quotetype = nil if @depth.zero?
      end
      @line.gsub!(/<p/,"<p class=\"blockquote_#{ @quotetype[1] if @quotetype }_#{ @depth }\"") unless @depth.zero?
    end

    # Kindle doesn't recognize text-transform: uppercase;
    def make_uppercase
      @line.gsub!(/<var>(.*?)<\/var>/){ "<cite>#{ $1.upcase }</cite>" }
      @line.gsub!(/<h1(.*?)>(.*?)<\/h1>/){ "<h1#{ $1 }>#{ $2.upcase }</h1><hr />" }
    end

    def change_footnote_references
      @line.gsub! /<sup id="fnref:.*?">/, ''
      @line.gsub! '</sup>', ''
      @line.gsub! /rel="footnote">(.*?)<\/a>/, '> [\1]</a>'
      @line.gsub!(/(<div class=.footnotes.>)/){ "<br style='page-break-before:always;'>#{ $1 }<h4>#{ @metadata['footnote_heading'] }</h4>" }
    end

    def process_footnotes
      @line.gsub!(/<p(.*?)>/){ "<p>" }
      @footnote_reference = /<li (id="fn.*")/.match(@line)[1] if @line.include?('<li id="fn')
      @line.gsub! /<li id="fn.*>/, ''
      @line.gsub! /<\/li>/, ''
      @line.gsub! /<ol>/, ''
      @line.gsub! /<\/ol>/, ''
      @line.gsub! /<a href="#fnref.*<\/a>/, ''
    end

    # Kindle doesn't display <ol> list numbers when jumping to a footnote, so replace them with conventional text
    def add_footnote
      @line.gsub! /<p>/, "<hr><p #{ @footnote_reference }><b>[#{ @footnote_number }]</b>: "
      @add_footnote = false
    end

    def make_footnote_paragraph
      @line.gsub! /<p/, "<p class='footnote' "
    end

    def change_resources_url_for_rails
     @line.gsub!(/href="(.*?.css)/){ "href=\"#{ @rails_resources_url }#{ $1 }" }
     @line.gsub!(/src="(.*?.jpg)/){ "src=\"#{ @rails_resources_url }#{ $1 }" }
    end

    def mark_merge_conflicts
     @line.gsub! /«««.*$/, '<span style="color:red;">'
     @line.gsub! '=======', '</span></p><p><span style="color:orange;">'
     @line.gsub! /»»».*$/, '</span></p>'
    end
  end
end