require 'open-uri'
require 'json'

class Convert

  def process
    get_less_files.each do |name|
      unless ['bootstrap.less', 'responsive.less'].include?(name)
        file = open_git_file("https://raw.github.com/twitter/bootstrap/master/less/#{name}")
        file = convert(file) 

        if name == 'progress-bars.less'
          file = fix_progress_bar(file)
        end

        if name == 'variables.less'
          file = insert_default_vars(file)
        end

        save_file(name, file) unless name == 'mixins.less'
      end
    end

    self.create_sass_files
  end
  
  def create_sass_files
    puts 'Creating sass files for testing'

    scss_files = 'stylesheets'

    Dir.glob(scss_files+'/*').each do |dir|
      file_or_dir = File.open dir

      if File.file? file_or_dir
        convert_scss(file_or_dir)
      else
        Dir.open(file_or_dir).each do |filename|
          file = File.open("#{file_or_dir.path}/#{filename}")
          next unless File.fnmatch? '**.scss', file
          convert_scss(file, 'compass_twitter_bootstrap/')
        end
      end
    end
  end

private

  # Get the sha of less branch
  def get_tree_sha
    sha = nil
    trees = open('https://api.github.com/repos/twitter/bootstrap/git/trees/master').read
    trees = JSON.parse trees

    trees['tree'].select do |t|
      if t['path'] == 'less'
        sha = t['sha']
      end
    end

    sha
  end

  def get_less_files
    file_list = []
    files = open("https://api.github.com/repos/twitter/bootstrap/git/trees/#{get_tree_sha}").read
    files = JSON.parse files
    files['tree'].each{|f| file_list << f['path']}

    file_list
  end


  def convert(file)
    file = replace_vars(file)
    file = replace_fonts(file)
    file = replace_font_family(file)
    file = replace_grads(file)
    file = replace_mixins(file)
    file = replace_less_extend(file)
    file = replace_includes(file)
    file = replace_spin(file)
    file = replace_opacity(file)
    file = replace_image_urls(file)

    file
  end

  def open_git_file(file)
    open(file).read
  end

  def save_file(name, content)
    name = name.gsub(/\.less/, '')
    f = File.open("stylesheets/compass_twitter_bootstrap/_#{name}.scss", "w+")
    f.write(content)
    f.close
    puts "Converted #{name}\n"
  end

  def replace_vars(less)
    less.gsub(/@/, '$')
  end

  def fix_progress_bar(less)
    less = less.gsub(/(\$)(-webkit-keyframes progress-bar-stripes)/, '@\2')
    less = less.gsub(/(\$)(-moz-keyframes)/, '@\2')
    less = less.gsub(/(\$)(keyframes progress-bar-stripes)/, '@\2')
  end

  def replace_fonts(less)
    less.gsub(/#font \> \.([\w-]+)/, '@include font-\1')
  end

  def replace_font_family(less)
    less.gsub(/#font \> #family \> \.([\w-]+)/, '@include font-family-\1')
  end

  def replace_grads(less)
    less.gsub(/#gradient \> \.([\w-]+)/, '@include gradient-\1')
  end

  def replace_mixins(less)
    less.gsub(/^\.([\w-]*)(\(.*\))([\s\{]+)$/, '@mixin \1\2\3')
  end

  def replace_includes(less)
    less.gsub(/\.([\w-]*)(\(.*\));?/, '@include \1\2;')
  end

  def replace_less_extend(less)
    less.gsub(/\#(\w+) \> \.([\w-]*)(\(.*\));?/, '@include \1-\2\3;')
  end

  def replace_spin(less)
    less.gsub(/spin/, 'adjust-hue')
  end

  def replace_opacity(scss)
    scss.gsub(/\@include opacity\((\d+)\)/) {|s| "@include opacity(#{$1.to_f / 100})"}
  end

  def replace_image_urls(less)
    less.gsub(/background-image: url\((.*)\);/) {|s| "background-image: image-url(\"#{$1.gsub('../img/','')}\");" }
  end

  def insert_default_vars(scss)
    scss.gsub(/^(\$.+);$/, '\1 !default;')
  end

  def convert_scss(file, folder='')
    sass_files = 'stylesheets_sass'
    system("sass-convert #{file.path} #{sass_files}/#{folder}#{File.basename(file, 'scss')}sass")
  end

end

Convert.new.process