# -*- ruby -*-

#encoding: utf-8

require 'pdf-reader'

require 'strelka'

require 'thingfish' unless defined?( Thingfish )

require 'thingfish/processor' unless defined?( Thingfish::Processor )

# Attach PDF metadata to the Adobe Portable Document Format.

class Thingfish::Processor::PDF < Thingfish::Processor

	extend Loggability

	# Package version

	VERSION = '0.1.0'

	# Version control revision

	REVISION = %q$Revision$

	# Loggability API -- log to the :thingfish logger

	log_to :thingfish

	# The list of handled types

	handled_types 'application/pdf'

	### Synchronous processor API -- extract metadata from uploaded PDFs

	###

	def on_request( request )

		reader   = ::PDF::Reader.new( request.body )

		metadata = self.extract_pdf_metadata( reader )

		request.add_metadata( metadata )

	end

	#########

	protected

	#########

	### Normalize metadata from the PDFReader object and return it as a hash.

	###

	def extract_pdf_metadata( reader )

		self.log.debug "Extracting PDF metadata..."

		pdf_metadata = {

			'pdf:version'   => reader.pdf_version,

			'pdf:pagecount' => reader.page_count,

		}.reject {|_,v| v.nil? }

		reader.info.each_pair do |key, val|

			pdf_metadata[ "pdf:#{key}" ] = val unless val.is_a?( ::PDF::Reader::Reference )

		end

		self.log.debug "  raw PDF metadata: %p" % [ pdf_metadata ]

		return pdf_metadata

	end

end # class Thingfish::Processor::PDF