class PrettyDiff::LineGenerator
  
  attr_reader :line
  
  def initialize(line)
    @line = line
  end
  
  def generate
    if line.added?
      added_html(content)
    elsif line.deleted?
      deleted_html(content)
    else
      not_modified_html(content)
    end
  end
  
private

  def content
    @_content ||= line.format
  end
  
  def wrapper_html
    %Q[<div>] +
    yield +
    %Q[</div>]
  end

  def added_html(text)
    wrapper_html { %Q[<span class="gi">#{text}</span>] }
  end

  def deleted_html(text)
    wrapper_html { %Q[<span class="gd">#{text}</span>] }
  end

  def not_modified_html(text)
    wrapper_html { %Q[#{text}] }
  end
  
end