Search PDF files for text in C++

//---------------------------------------------------------------------------------------
// Copyright (c) 2001-2023 by Apryse Software Inc. All Rights Reserved.
// Consult legal.txt regarding legal and license information.
//---------------------------------------------------------------------------------------

// This sample shows how to use pdftron.PDF.TextSearch to search text on PDF pages
// using regular expressions. TextSearch utility class builds on functionality 
// available in TextExtractor to simplify most common search operations.

#include <PDF/PDFNet.h>
#include <PDF/PDFDoc.h>
#include <PDF/TextSearch.h>
#include <PDF/Annot.h>
#include <iostream>
#include "../../LicenseKey/CPP/LicenseKey.h"

using namespace std;
using namespace pdftron;
using namespace PDF;
using namespace SDF;
using namespace Common;

#undef max
#undef min
#include <algorithm>

int main(int argc, char *argv[])
{
	int ret = 0;
	PDFNet::Initialize(LicenseKey);
	std::string input_path =  "../../TestFiles/credit card numbers.pdf";
	const char* filein = argc>1 ? argv[1] : input_path.c_str();

	try
	{
		PDFDoc doc(filein);
		doc.InitSecurityHandler();

		TextSearch txt_search;
		TextSearch::Mode mode = TextSearch::e_whole_word | TextSearch::e_page_stop;
		UString pattern( "joHn sMiTh" );

		//call Begin() method to initialize the text search.
		txt_search.Begin( doc, pattern, mode );

		int step = 0;
	
		//call Run() method iteratively to find all matching instances.
		while ( true )
		{
			SearchResult result = txt_search.Run();

			if ( result )
			{
				if ( step == 0 )
				{	// Step 0: found "John Smith"
					// note that, here, 'ambient_string' and 'hlts' are not written to, 
					// as 'e_ambient_string' and 'e_highlight' are not set.

					cout << result.GetMatch() << "'s credit card number is: " << endl;

					//now switch to using regular expressions to find John's credit card number
					mode = txt_search.GetMode();
					mode |= TextSearch::e_reg_expression | TextSearch::e_highlight;
					txt_search.SetMode(mode);
					pattern = "\\d{4}-\\d{4}-\\d{4}-\\d{4}"; //or "(\\d{4}-){3}\\d{4}"
					txt_search.SetPattern(pattern);

					++step;
				}
				else if ( step == 1 )
				{
					//step 1: found John's credit card number
					cout << "  " << result.GetMatch() << endl;

					//note that, here, 'hlts' is written to, as 'e_highlight' has been set.
					//output the highlight info of the credit card number.
					Highlights hlts = result.GetHighlights();
					hlts.Begin(doc);
					while ( hlts.HasNext() )
					{
						cout << "The current highlight is from page: " << hlts.GetCurrentPageNumber() << endl;
						hlts.Next();
					}

					//see if there is an AMEX card number
					pattern = "\\d{4}-\\d{6}-\\d{5}";
					txt_search.SetPattern(pattern);

					++step;
				}
				else if ( step == 2 )
				{
					//found an AMEX card number
					cout << "\nThere is an AMEX card number:\n  " << result.GetMatch() << endl;

					//change mode to find the owner of the credit card; supposedly, the owner's
					//name proceeds the number
					mode = txt_search.GetMode();
					mode |= TextSearch::e_search_up;
					txt_search.SetMode(mode);
					pattern = "[A-z]++ [A-z]++";
					txt_search.SetPattern(pattern);

					++step;
				}
				else if ( step == 3 )
				{
					//found the owner's name of the AMEX card
					cout << "Is the owner's name:\n  " << result.GetMatch() << "?\n" << flush;

					//add a link annotation based on the location of the found instance
					Highlights hlts = result.GetHighlights();
					hlts.Begin(doc);
					while ( hlts.HasNext() )
					{
						Page cur_page= doc.GetPage(hlts.GetCurrentPageNumber());
						const double *quads;
						int quad_count = hlts.GetCurrentQuads(quads);
						for ( int i = 0; i < quad_count; ++i )
						{
							//assume each quad is an axis-aligned rectangle
							const double *q = &quads[8*i];
							double x1 = min(min(min(q[0], q[2]), q[4]), q[6]);
							double x2 = max(max(max(q[0], q[2]), q[4]), q[6]);
							double y1 = min(min(min(q[1], q[3]), q[5]), q[7]);
							double y2 = max(max(max(q[1], q[3]), q[5]), q[7]);
							Annots::Link hyper_link = Annots::Link::Create(doc, Rect(x1, y1, x2, y2), Action::CreateURI(doc, "http://www.pdftron.com"));
							cur_page.AnnotPushBack(hyper_link);
						}
						hlts.Next();
					}
					std::string output_path = "../../TestFiles/Output/";
					doc.Save((output_path + "credit card numbers_linked.pdf").c_str(), SDFDoc::e_linearized, 0);
					break;
				}
			}
			else if ( result.IsPageEnd() )
			{
				//you can update your UI here, if needed
			}
			else  
			{
				assert (result.IsDocEnd());
				break;
			}
		}
	}
	catch(Exception& e)
	{
		cout << e << endl;
		ret = 1;
	}
	catch(...)
	{
		cout << "Unknown Exception" << endl;
		ret = 1;
	}

	PDFNet::Terminate();
	return ret;
}