rename2exiftime

#! /usr/bin/env ruby

require 'rubygems'
require 'extexif'
require 'optparse'

def main
   simulation = nil
   quiet = nil
   help = nil

   OptionParser.new{|opt|
      opt.on('-s') { simulation = true }
      opt.on('-q', '--quiet') { quiet = true }
      opt.on('-h', '--help') { help = true }
   }.parse!(ARGV)

   if help
      usage
      exit
   end

   ARGV.each do |f|
      next unless(File.file?(f))

      begin
         img = ExtExif.new(f)
         new_name = img['DateTimeOriginal'].gsub(/:/, '.').gsub(/\s/, '_')

         if(new_name !~ /^[\d\._]+$/)
            raise f + ": Could not read exif data."
         end

         new_name = File.join(File.dirname(f), new_name + File.extname(f))
         if(File.exists?(new_name))
            raise f + ": " + new_name + ' is already exists.'
         end

         puts f + ' to ' + new_name if(quiet.nil?)
         File.rename(f, new_name) if(simulation.nil?)
      rescue => err
         puts err
      end
   end
end

def usage
   puts <<-EOF
-h,--help   show this message.
-q,--quiet  quiet mode.
-s          only simulation.
EOF
end

main