Fixes

Gemfile

@@ -7,11 +7,3 @@ group :development, :test do
   gem 'rspec', '>= 3'
   gem 'tilt'
 end
-
-group :coderay do
-  gem 'coderay'
-end
-
-group :pygments do
-  gem 'pygments.rb'
-end

lib/org-ruby/headline.rb

@@ -45,14 +45,15 @@ class Headline < Line
     # This matches a headline marked as COMMENT
     CommentHeadlineRegexp = /^COMMENT\s+/
 
-    def initialize(line, parser = nil, offset=0)
+    def initialize(line, parser = nil, offset = 0)
       super(line, parser)
       @body_lines = []
       @tags = []
       @export_state = :exclude
       @property_drawer = { }
       if (@line =~ LineRegexp) then
-        @level = $&.strip.length + offset
+        new_offset = (parser && parser.title?) ? offset + 1 : offset
+        @level = $&.strip.length + new_offset
         @headline_text = $'.strip
         if (@headline_text =~ TagsRegexp) then
           @tags = $&.split(/:/)              # split tag text on semicolon
@@ -88,6 +89,11 @@ def paragraph_type
       :"heading#{@level}"
     end
 
+    def headline_level
+      title_offset = (parser && parser.title?) ? 1 : 0
+      level - title_offset
+    end
+
     ######################################################################
     private
 

lib/org-ruby/highlighter.rb

@@ -0,0 +1,61 @@
+module Orgmode
+  # Highlight code
+  module Highlighter
+    def self.highlight(code, lang)
+      highlighter = guess_highlighter
+      highlighter.highlight(code, lang)
+    end
+
+    def self.guess_highlighter
+      return RougeHighliter if gem_present?('rouge')
+      return PygmentsHighliter if gem_present?('pygments.rb')
+      return CodeRayHighliter if gem_present?('coderay')
+
+      DefaultHighliter
+    end
+
+    def self.gem_present?(gem)
+      Gem::Specification.find_all_by_name(gem).any?
+    end
+
+    # Default highliter does nothing to code
+    class DefaultHighliter
+      def self.highlight(buffer, _lang)
+        buffer
+      end
+    end
+
+    # Pygments wrapper
+    class PygmentsHighliter
+      def self.highlight(buffer, lang)
+        require 'pygments'
+        if Pygments::Lexer.find_by_alias(lang)
+          Pygments.highlight(buffer, lexer: lang)
+        else
+          Pygments.highlight(buffer, lexer: 'text')
+        end
+      end
+    end
+
+    # CodeRay wrapper
+    class CodeRayHighliter
+      def self.highlight(buffer, lang)
+        require 'coderay'
+        CodeRay.scan(buffer, lang).html(wrap: nil, css: :style)
+      rescue ArgumentError => _e
+        CodeRay.scan(buffer, 'text').html(wrap: nil, css: :style)
+      end
+    end
+
+    # Rouge wrapper
+    class RougeHighliter
+      def self.highlight(buffer, lang)
+        require 'rouge'
+        formatter = Rouge::Formatters::HTMLLegacy.new
+        lexer = Rouge::Lexer.find_fancy(lang, buffer) ||
+                Rouge::Lexers::PlainText
+        formatter.format(lexer.lex(buffer.strip))
+      end
+    end
+  end
+end