#!/usr/bin/env ruby

##
# Recursively deletes files from a directory (relative to the cache directory)
# if they are older than the specified date.
#
# Author: Nikhil Gupte <nikhil AT aurigalogic DOT com>
#
# This file should be kept in RAILS_ROOT/scripts
# USAGE: cachedel [dir-relative-to-cache-dir] <age-in-minutes>
##

RAILS_ROOT = File.join(File.dirname(__FILE__), '..')

# change this if your cache dir is elsewhere.
# WARNING: This should only be used if you have a dir exclusively for caching
CACHE_DIR = File.expand_path('public/cache', RAILS_ROOT)

############# You don't need to modify anything below this line ##########################
class Fixnum
  def minutes() self * 60 end
  def ago() Time.now - self end
end

def del_old_files(dir_path, max_age)
  Dir.foreach(dir_path) do |file|
    unless file == '.' || file == '..'
      file = "#{dir_path}/#{file}"
      if deletable?(file, max_age)
        print "- #{file} [#{File.ctime(file)}].\n"
        #File.delete(file)
      else
        print "+ #{file} [#{File.ctime(file)}].\n"
      end  
      del_old_files(file, max_age) if File.directory?(file)
    end  
  end  
end

def deletable?(file, max_age)
  !File.directory?(file) && File.ctime(file) < max_age.ago
end

if ARGV.size > 0 && ARGV[0] != 'help'
  begin
    dir = File.expand_path(ARGV[0], CACHE_DIR)
    raise "path-to-directory must be a sub directory of #{CACHE_DIR}" unless dir.index(CACHE_DIR) == 0
    max_age = (ARGV[1] || 10).to_i
    print "Deleting files from \"#{dir}\" older than #{max_age} minutes\n"
    del_old_files(dir, max_age.minutes);
  rescue Exception => err
    print err.to_s + "\n"
    exit(1)
  end
else
  print "Deletes files older than the specified max age from the specified directory relative to the cache directory
SYNTAX:
    cachedel [path-to-directory] <max-age-in-minutes>
  WHERE:
    path-to-directory is relative to #{CACHE_DIR}
    max-age-in-minutes defaults to 10
EXAMPLE:
    cachedel home 20
    will delete files from #{CACHE_DIR}/home
"
  exit(0)
end