Search PDF files for text in Obj-C

//---------------------------------------------------------------------------------------
// Copyright (c) 2001-2021 by PDFTron Systems Inc. All Rights Reserved.
// Consult legal.txt regarding legal and license information.
//---------------------------------------------------------------------------------------

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

// This sample illustrates the basic text search capabilities of PDFNet.

int main(int argc, char *argv[])
{
    @autoreleasepool {

        int ret = 0;
        [PTPDFNet Initialize: 0];
        NSString *input_path = @"../../TestFiles/credit card numbers.pdf";

        @try
        {
            PTPDFDoc *doc = [[PTPDFDoc alloc] initWithFilepath: input_path];
            [doc InitSecurityHandler];

            PTTextSearch *txt_search = [[PTTextSearch alloc] init];
            unsigned int mode = e_ptwhole_word | e_ptpage_stop;
            NSString *pattern = @"joHn sMiTh";

            //call Begin() method to initialize the text search.
            [txt_search Begin: doc pattern: pattern mode: mode start_page: -1 end_page: -1];

            int step = 0;
            
            //call Run() method iteratively to find all matching instances.
            while ( YES )
            {
                PTSearchResult *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.

                        NSLog(@"%@'s credit card number is: ", [result GetMatch]);
                        //now switch to using regular expressions to find John's credit card number
                        mode = [txt_search GetMode];
                        mode |= e_ptreg_expression | e_pthighlight;
                        [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
                        NSLog(@"  %@", [result GetMatch]);

                        //note that, here, 'hlts' is written to, as 'e_highlight' has been set.
                        //output the highlight info of the credit card number.
                        PTHighlights *hlts = [result GetHighlights];
                        [hlts Begin: doc];
                        while ( [hlts HasNext] )
                        {
                            NSLog(@"The current highlight is from page: %d", [hlts GetCurrentPageNumber]);
                            [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
                        NSLog(@"\nThere is an AMEX card number:\n  %@", [result GetMatch]);

                        //change mode to find the owner of the credit card; supposedly, the owner's
                        //name proceeds the number
                        mode = [txt_search GetMode];
                        mode |= e_ptsearch_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
                        NSLog(@"Is the owner's name:\n  %@?\n", [result GetMatch]);

                        //add a link annotation based on the location of the found instance
                        PTHighlights *hlts = [result GetHighlights];
                        [hlts Begin: doc];
                        while ( [hlts HasNext] )
                        {
                            PTPage *cur_page = [doc GetPage: [hlts GetCurrentPageNumber]];
                            PTVectorQuadPoint *quads = [hlts GetCurrentQuads];
                            int i = 0;
                            for ( ; i < [quads size]; ++i )
                            {
                                //assume each quad is an axis-aligned rectangle
                                PTQuadPoint *q = [quads get: i];
                                double x1 = MIN(MIN(MIN([[q getP1] getX], [[q getP2] getX]), [[q getP3] getX]), [[q getP4] getX]);
                                double x2 = MAX(MAX(MAX([[q getP1] getX], [[q getP2] getX]), [[q getP3] getX]), [[q getP4] getX]);
                                double y1 = MIN(MIN(MIN([[q getP1] getY], [[q getP2] getY]), [[q getP3] getY]), [[q getP4] getY]);
                                double y2 = MAX(MAX(MAX([[q getP1] getY], [[q getP2] getY]), [[q getP3] getY]), [[q getP4] getY]);
                                PTPDFRect * rect = [[PTPDFRect alloc] initWithX1: x1 y1: y1 x2: x2 y2: y2];
                                PTAction *action = [PTAction CreateURI: [doc GetSDFDoc] uri: @"http://www.pdftron.com"];

                                PTLink *hyper_link = [PTLink CreateWithAction: [doc GetSDFDoc] pos: rect action: action];
                                [cur_page AnnotPushBack: hyper_link];
                            }
                            [hlts Next];
                        }
                        [doc SaveToFile: @"../../TestFiles/Output/credit card numbers_linked.pdf" flags: e_ptlinearized];

                        break;
                    }
                }

                else if ( [result IsPageEnd] )
                {
                    //you can update your UI here, if needed
                }

                else
                {
                    break;
                }
            }
        }

        @catch(NSException *e)
        {
            NSLog(@"%@", e.reason);
            ret = 1;
        }
        [PTPDFNet Terminate: 0];
        return ret;
    }
}