#
# Created by Eric Lindvall <eric@sevenscale.com>
#
# Please note: The numbers provided are of self and children, meaning, you
# won't be able to add them all up to get the total memory usage of the app.
#
# It also does not take into account memory that was allocated and then freed.
#
# It is intended to give a simple overview of allocations to track down gross
# offenders, not give an exact view of your memory usage.
#

if GC.respond_to?(:enable_stats)
  module RequireTracking
    def require(*args)
      start_allocated_size = GC.allocated_size
      super
    ensure
      $require_stats[args.first] += (GC.allocated_size - start_allocated_size)
    end
    
    def numeric_thousands_indicators(number)
      number.to_s.gsub(/(\d)(?=\d{3}+(?:\.|$))(\d{3}\..*)?/,'\1,\2')
    end
  end

  Object.send(:include, RequireTracking)
  Kernel.send(:include, RequireTracking)
  
  $require_stats = Hash.new { |h,k| h[k] = 0 }
  GC.enable_stats
  GC.clear_stats
  
  at_exit do
    puts "Memory used by file:"
    puts " %40s %s" % [ 'File', 'KB' ]
    puts " %40s %s" % [ '-------------', '--------' ]
    $require_stats.sort_by { |k,v| -v }.slice(0, $require_stats_top || 20).each do |(k,v)|
      puts "%40s: %s" % [ k, numeric_thousands_indicators(v / 1024) ]
    end
  end
else
  puts "Warning: Not running with an interpreter with GC statistics"
end