#
# Copyright Michael Orlitzky
#
# http://michael.orlitzky.com/
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# http://www.fsf.org/licensing/licenses/gpl.html
#

require 'open-uri'
require 'vendor/ruby-progressbar/progressbar'

# Just a couple of convenience methods for URIs.
# These could be monkey-patched in, but with only
# a few methods, that'd be asking (unnecessarily)
# for trouble.
class UriUtilities

  # Download the given URI object to <outfile_name>.
  # Should use the progress_proc parameter to show
  # a progress bar using the Ruby/ProgressBar library.
  def download_with_progress_bar(uri, outfile_name)
    # We wrap the whole thing in a begin/rescue so that
    # we can clean up afterwards in case of an error.
    begin
      File.open(outfile_name, 'wb') do |outfile|
        pbar = nil
        uri.open(:content_length_proc => lambda {|content_length|
                   if content_length && (0 < content_length)                   
                     pbar = ProgressBar.new("Download", content_length)
                     pbar.instance_eval { @bar_mark = '=' }
                     pbar.file_transfer_mode
                   end
                 },
                 :progress_proc => lambda {|size|
                   pbar.set(size) if pbar
                 }) do |video_file|
          outfile.write(video_file.read)
        end      
      end

      # Toss out an empty line to get rid of the progress bar.
      # Normally, it would remain on the shell's "current" line.
      puts ''

    rescue Errno::EACCES => e
      # Don't delete the file if it's unwritable.
      raise(e)
    rescue => e
      # Here we get rid of the output file if there was an error.
      # We test File.exists? first since the first line, the open()
      # call, could theoretically fail.
      File.delete(outfile_name) if File.exists?(outfile_name)
      raise(e)
    end
  end
  
end