//---------------------------------------------------------------------------------------
// Copyright (c) 2001-2012 by PDFTron Systems Inc. All Rights Reserved.
// Consult legal.txt regarding legal and license information.
//---------------------------------------------------------------------------------------

#import <OBJC/PDFNetOBJC.h>
#import <Foundation/Foundation.h>

//---------------------------------------------------------------------------------------
// 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. 
//---------------------------------------------------------------------------------------

static void ProcessElements(ElementReader *reader, ElementWriter *writer) 
{
	Element *element;	
	while (element = [reader Next]) 	// Read page contents
	{
		switch ([element GetType])
		{		
		case e_image: 
		case e_inline_image: 
			// remove all images by skipping them			
			break;
		case e_text_obj:// Process text strings...
			{
				// Set all text to blue color.
				GState *gs = [element GetGState];
				[gs SetFillColorSpace: [ColorSpace CreateDeviceRGB]];
				ColorPt *cp = [[ColorPt alloc] initWithX: 0 y: 0 z: 1 w: 0];
				[gs SetFillColorWithColorPt: cp];
				[writer WriteElement: element];
				break;
			}
		case e_form:// Recursively process form XObjects
			{
				[reader FormBegin];
                ProcessElements(reader, writer);
				[reader End]; 				
				break; 
			}
		default:
                [writer WriteElement: element];
		}
	}
}

int main(int argc, char *argv[])
{
	NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
	
	int ret = 0;
	[PDFNet Initialize: 0];

	@try 
	{
		NSLog(@"-------------------------------------------------");

		// Open the test file
		NSLog(@"Opening the input file...");
		PDFDoc *doc = [[PDFDoc alloc] initWithFilepath: @"../../TestFiles/newsletter.pdf"];
		[doc InitSecurityHandler];

		ElementWriter *writer = [[ElementWriter alloc] init];
		ElementReader *reader = [[ElementReader alloc] init];

		PageIterator *itr = [doc GetPageIterator: 1];

		while ([itr HasNext])
		{
			Page *page = [itr Current];
			[reader ReaderBeginWithPage: page ocg_context: 0];
			[writer Begin: page placement: e_replacement page_coord_sys: NO];
			ProcessElements(reader, writer);
			[writer End];
			[reader End];
			[itr Next];
		}

        [doc SaveToFile: @"../../TestFiles/Output/newsletter_edited.pdf" flags: e_remove_unused];		
        NSLog(@"Done. Result saved in newsletter_edited.pdf...");
	}
	@catch(NSException *e)
	{
		NSLog(@"Caught PDFNet exception: %@", [e reason]);
		ret = 1;
	}
	
	[pool release];
    return ret;
}