(Objective-C) Generate TOTP using Base32 Secret (6 Digits, Time-based, 30-second period)

Generates a 6-digit time-based TOTP code using a base32 secret with a 30-second time period.

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#import <CkoCrypt2.h>
#import <NSString.h>
#import <CkoStringBuilder.h>

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.
// 
CkoCrypt2 *crypt = [[CkoCrypt2 alloc] init];

// Base32 secret key:
NSString *secretKey = @"oebf ytfl qmzb p4xd 2ztf zyz4 hjrw 3uyo";

CkoStringBuilder *sbKey = [[CkoStringBuilder alloc] init];
BOOL success = [sbKey Append: secretKey];

// Remove SPACE chars.
int numRemoved = [[sbKey Replace: @" " replacement: @""] intValue];

// Note: A new token is generated every 30 seconds.  You must generate within the same 30 second interval to get the same result.

// Generate 6 digits.
int numDigits = 6;
// 30 second time period.
int timePeriod = 30;
NSLog(@"%@%@",@"Your token is: ",[crypt Totp: [sbKey GetAsString] secretEnc: @"base32" t0: @"0" tNow: @"" tStep: [NSNumber numberWithInt: timePeriod] numDigits: [NSNumber numberWithInt: numDigits] truncOffset: [NSNumber numberWithInt: -1] hashAlg: @"sha1"]);