# encoding: utf-8

module Backup
  module Cleaner
    class << self

      ##
      # Logs warnings if any temporary files still exist
      # from the last time this model/trigger was run,
      # then removes the files.
      def prepare(model)
        @model = model

        messages = []
        if packaging_folder_dirty?
          messages << <<-EOS
            The temporary backup folder still contains files!
            '#{ File.join(Config.tmp_path, @model.trigger) }'
            These files will now be removed.
          EOS
          FileUtils.rm_rf(File.join(Config.tmp_path, @model.trigger))
        end

        package_files = tmp_path_package_files
        unless package_files.empty?
          # the chances that tmp_path would be dirty
          # AND package files exist are practically nil
          messages << ('-' * 74) unless messages.empty?

          messages << <<-EOS
            The temporary backup folder '#{ Config.tmp_path }'
            appears to contain the package files from the previous backup!
            #{ package_files.join("\n") }
            These files will now be removed.
          EOS
          package_files.each {|file| FileUtils.rm_f(file) }
        end

        unless messages.empty?
          Logger.warn Errors::CleanerError.new(<<-EOS)
            Cleanup Warning
            #{ messages.join("\n") }
            Please check the log for messages and/or your notifications
            concerning this backup: '#{ @model.label } (#{ @model.trigger })'
            The temporary files which had to be removed should not have existed.
          EOS
        end
      end

      ##
      # Remove the temporary folder used during packaging
      def remove_packaging(model)
        Logger.info "Cleaning up the temporary files..."
        FileUtils.rm_rf(File.join(Config.tmp_path, model.trigger))
      end

      ##
      # Remove the final package files from tmp_path
      # Note: 'force' is used, since a Local Storage may *move* these files.
      def remove_package(package)
        Logger.info "Cleaning up the package files..."
        package.filenames.each do |file|
          FileUtils.rm_f(File.join(Config.tmp_path, file))
        end
      end

      ##
      # Logs warnings if any temporary files still exist
      # when errors occur during the backup
      def warnings(model)
        @model = model

        messages = []
        if packaging_folder_dirty?
          messages << <<-EOS
            The temporary backup folder still contains files!
            '#{ File.join(Config.tmp_path, @model.trigger) }'
            This folder may contain completed Archives and/or Database backups.
          EOS
        end

        package_files = tmp_path_package_files
        unless package_files.empty?
          # the chances that tmp_path would be dirty
          # AND package files exist are practically nil
          messages << ('-' * 74) unless messages.empty?

          messages << <<-EOS
            The temporary backup folder '#{ Config.tmp_path }'
            appears to contain the backup files which were to be stored:
            #{ package_files.join("\n") }
          EOS
        end

        unless messages.empty?
          Logger.warn Errors::CleanerError.new(<<-EOS)
            Cleanup Warning
            #{ messages.join("\n") }
            Make sure you check these files before the next scheduled backup for
            '#{ @model.label } (#{ @model.trigger })'
            These files will be removed at that time!
          EOS
        end
      end

      private

      def packaging_folder_dirty?
        !Dir[File.join(Config.tmp_path, @model.trigger, '*')].empty?
      end

      def tmp_path_package_files
        Dir[File.join(
          Config.tmp_path,
          "????.??.??.??.??.??.#{ @model.trigger }.tar{,[.-]*}"
        )]
      end

    end
  end
end