# This profiler run simulates Shopify.
# We are looking in the tests directory for liquid files and render them within the designated layout file.
# We will also export a substantial database to liquid which the templates can render values of. 
# All this is to make the benchmark as non syntetic as possible. All templates and tests are lifted from
# direct real-world usage and the profiler measures code that looks very similar to the way it looks in 
# Shopify which is likely the biggest user of liquid in the world which something to the tune of several 
# million Template#render calls a day. 

require 'rubygems'
require 'active_support'
require 'yaml'
require 'digest/md5'
require File.dirname(__FILE__) + '/shopify/liquid'
require File.dirname(__FILE__) + '/shopify/database.rb'

require "ruby-prof" rescue fail("install ruby-prof extension/gem")

class ThemeProfiler
  
  # Load all templates into memory, do this now so that 
  # we don't profile IO. 
  def initialize
    @tests = Dir[File.dirname(__FILE__) + '/tests/**/*.liquid'].collect do |test|
      next if File.basename(test) == 'theme.liquid'
      
      theme_path = File.dirname(test) + '/theme.liquid'
      
      [File.read(test), (File.file?(theme_path) ? File.read(theme_path) : nil), test]
    end.compact
  end  
  
  
  def profile
    RubyProf.measure_mode = RubyProf::WALL_TIME
    
    # Dup assigns because will make some changes to them
    assigns = Database.tables.dup
    
    @tests.each do |liquid, layout, template_name|
      
      # Compute page_tempalte outside of profiler run, uninteresting to profiler
      html = nil
      page_template = File.basename(template_name, File.extname(template_name))
      
      # Profile compiling and rendering both
      RubyProf.resume { html = compile_and_render(liquid, layout, assigns, page_template) }
      
      # return the result and the MD5 of the content, this can be used to detect regressions between liquid version
      $stdout.puts "* rendered template %s, content: %s" % [template_name, Digest::MD5.hexdigest(html)]
      
      # Uncomment to dump html files to /tmp so that you can inspect for errors
      # File.open("/tmp/#{File.basename(template_name)}.html", "w+") { |fp| fp <<html}
    end
  
    RubyProf.stop    
  end
  
  def compile_and_render(template, layout, assigns, page_template)    
    tmpl = Liquid::Template.new
    tmpl.assigns['page_title'] = 'Page title'
    tmpl.assigns['template'] = page_template
    
    content_for_layout = tmpl.parse(template).render(assigns)
    
    if layout
      assigns['content_for_layout'] = content_for_layout      
      tmpl.parse(layout).render(assigns)
    else
      content_for_layout
    end    
  end
end


  profiler = ThemeProfiler.new

  puts 'Running profiler...'

  results  = profiler.profile
  
  puts 'Success'
  puts

[RubyProf::FlatPrinter, RubyProf::GraphPrinter, RubyProf::GraphHtmlPrinter, RubyProf::CallTreePrinter].each do |klass|
  filename = (ENV['TMP'] || '/tmp') + (klass.name.include?('Html') ? "/liquid.#{klass.name.downcase}.html" : "/liquid.#{klass.name.downcase}.txt")
  filename.gsub!(/:+/, '_')
  File.open(filename, "w+") { |fp| klass.new(results).print(fp) }
  $stderr.puts "wrote #{klass.name} output to #{filename}"
end