module EY
  module Backup
    class BackupSet < Struct.new(:name, :keys)
      include EY::Backup::Logging
      extend  EY::Backup::Logging

      attr_accessor :files

      MULTIPART_EXTENSION = /\.part\d+/

      def self.parse(objects)
        objects.map {|o| new(o[:name], o[:keys]) }
      end

      def self.from(database, file)
        backup = new(File.basename(file), [])
        backup.files = [file]
        backup
      end

      def self.cleanup(database, keep)
        say "Cleanup for #{database}"
        backups_for(database)[0...(-keep)].each do |backup|
          say "deleting: #{backup.name}"
          backup.delete!
        end
      end

      def self.list_all
        list('all', backups)
      end

      def self.backups
        EY::Backup.config.databases.map {|db| backups_for(db) }.flatten
      end

      def self.list(database, backups = backups_for(database))
        info "Listing database backups for #{database}"

        info "#{backups.size} backup(s) found"

        backups.each_with_index do |db, i|
          info "#{i}:#{database} #{db.normalized_name}"
        end

        backups
      end

      def self.backups_for(database_name)
        s3_objects = EY::Backup.bucket_minder.list(:prefix => "#{EY::Backup.config.environment}.#{database_name}", :print => false)
        parse(s3_objects).sort
      end

      def self.upload(database, file)
        EY::Backup.bucket_minder.name = "#{EY::Backup.config.environment}.#{database}/#{File.basename(file)}"
        EY::Backup.bucket_minder.upload_object(file, false)
      end

      def self.download(database, index)
        fatal "You didn't specify a database name: e.g. 1:rails_production" if database.empty? || index.empty?

        backup = backups_for(database)[index.to_i]

        fatal "No backup found for database #{database}: requested index: #{index}" unless backup

        backup.download!

        backup
      end

      def initialize(*)
        super

        @files = []
      end

      def parts
        [keys.size, files.size].max
      end

      def normalized_name
        normalize(name)
      end

      def upload!(database)
        files.each do |file|
          EY::Backup.bucket_minder.name = "#{EY::Backup.config.environment}.#{database}/#{File.basename(file)}"
          EY::Backup.bucket_minder.upload_object(file, false)
          info "successful upload: #{file}"
        end
      end

      def download!
        keys.each do |key|
          info "Downloading #{key}"
          filename = File.join(EY::Backup.base_path, normalize(key))
          File.open(filename, 'wb') do |f|
            EY::Backup.bucket_minder.stream(key) do |chunk|
              f << chunk
            end
          end

          files << filename
        end
      end

      def delete!
        keys.each do |key|
          EY::Backup.bucket_minder.remove_object(key)
        end
      end

      def rm!
        files.each do |file|
          FileUtils.rm(file)
        end
      end

      def normalize(o)
        o.gsub(/^.*?\//, '')
      end

      def <=>(o)
        self.name <=> o.name
      end
    end
  end
end