gistfile1.rb

require 'zip/zip'
require 'zip/zipfilesystem'
require 'guid'

class AlbumZipImporter
  attr_accessor :file, :photos, :album, :guid, :unzip_dir

  def initialize album_name, file
    @file = file
    @photos = []
    @album = Album.find_or_create_by_name album_name
    @guid = Guid.new.hexdigest
    @unzip_dir = "#{RAILS_ROOT}/tmp/#{@guid}"

    # Extract the files into a tmp directory based on @guid
    set_photos

    # Remove everything from the album and replace it with the files, in the
    # order they appear in the zip file
    create_album

    # Destroy the tmp/guid directory recursively
    destroy_tmp_files
  end

  def destroy_tmp_files
    puts "in destroy_tmp_files"
    `rm -fr #{@unzip_dir}`
  end

  def set_photos
    puts "in set_photos"
    ordered_files = []
    Zip::ZipFile.open(@file){|zf|
      zf.each{|file|
        ordered_files << file
      }
      ordered_files = ordered_files.sort_by{|file| file.name}
      ordered_files.each{|file|
        puts file.name
        fpath = File.join(@unzip_dir, file.name)
        FileUtils.mkdir_p(File.dirname(fpath))
        # unzip the file into the tmp dir, then add its path into the photos array
        zf.extract(file, fpath)
        @photos << fpath
      }
    }
  end

  def create_album
    @album.photos.map(&:destroy)
    @photos.each do |photo|
      p = Photo.new
      p.image = File.open(photo)
      @album.photos << p
    end
    album.save
  end
end