#---------------------------------------------------------------------------------------
# Copyright (c) 2001-2011 by PDFTron Systems Inc. All Rights Reserved.
# Consult legal.txt regarding legal and license information.
#---------------------------------------------------------------------------------------

require '../../../Lib/PDFNetRuby'
include PDFNetRuby

#---------------------------------------------------------------------------------------
# The sample code shows how to edit the page display list and how to modify graphics state 
# attributes on existing Elements. In particular the sample program strips all images from 
# the page and changes text color to blue. 
#---------------------------------------------------------------------------------------

def ProcessElements(reader, writer)
	element = reader.Next()	 # Read page contents
	while !element.nil? do
		type = element.GetType()
		case type
		when Element::E_image
		# remove all images by skipping them
		when Element::E_inline_image	
			# remove all images by skipping them
		when Element::E_text	# Process text strings...
			# Set all text to blue color.
			gs = element.GetGState()
			gs.SetFillColorSpace(ColorSpace.CreateDeviceRGB())
			cp = ColorPt.new(0, 0, 1)
			gs.SetFillColor(cp)
			writer.WriteElement(element)
		when Element::E_form	# Recursively process form XObjects
			reader.FormBegin()
			ProcessElements(reader, writer)
			reader.End()
		else
			writer.WriteElement(element)
		end
		element = reader.Next()
	end
end

	PDFNet.Initialize()
	
	# Relative path to the folder containing the test files.
	input_path = "../../TestFiles/"
	output_path = "../../TestFiles/Output/"
	input_filename = "newsletter.pdf"
	output_filename = "newsletter_edited.pdf"
	
	puts "-------------------------------------------------"
	
	# Open the test file
	puts "Opening the input file..."
	doc = PDFDoc.new(input_path + input_filename)
	doc.InitSecurityHandler()
	
	writer = ElementWriter.new()
	reader = ElementReader.new()
	
	itr = doc.GetPageIterator()
	
	while itr.HasNext() do
		page = itr.Current()
		reader.Begin(page)
		writer.Begin(page, ElementWriter::E_replacement, false)
		ProcessElements(reader, writer)
		writer.End()
		reader.End()
		itr.Next()
	end
		
	doc.Save(output_path + output_filename, SDFDoc::E_remove_unused)
	doc.Close()
	puts "Done. Result saved in " + output_filename + "..."