C++ file

#include<stdio.h>
#include<iostream>
#include<string.h>
#include<fstream>
#include<random>
#include <cstdlib> 
#include <cstring> 
#include <set>
#include<regex>
#include<ctime>
using namespace std;
class transaction{
	public: char name[20];
	char phone[11];
	char acc_no[12];
	const char* age;
	char dob[10];
	std::string type;
	char buffer[150];
	char secretPIN[5];
	char amount[5];
	char total[5];
	char email[20];
	std::string admin_id;
	std::string password;
	transaction(){
	
	admin_id = "OurBank@Ifrit";
	password = "RA@LLss2024*";}
bool isValidDate(const std::string& date){
    regex dateRegex(R"(^(0[1-9]|[1-2][0-9]|3[0-1])/(0[1-9]|1[0-2])/((19|20)\d{2})$)");

    return std::regex_match(date, dateRegex);}
    
    bool isValidEmail(const std::string& email) {
    regex emailRegex(R"(^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$)");

    return regex_match(email, emailRegex);    
}
	bool isAccountNumberExist(const std::string& accNo){
    std::ifstream inputFile("AccountNew.txt");
    std::string line;
    while (std::getline(inputFile, line)){
        std::istringstream iss(line);
        std::string accNoFromFile;
        std::getline(iss, accNoFromFile, '|');
        if (accNoFromFile == accNo) {
            inputFile.close();
            return true;
        }
    }
    inputFile.close();
    return false;
}

bool isSecretPINUnique(const std::string& filename, const char* secretPIN) {
    std::ifstream file(filename);
    if (!file) {
        return true;
    }

    std::string line;
    while (std::getline(file, line)) {
        std::string storedSecretPIN = line.substr(line.find_last_of('|') + 1);
        if (storedSecretPIN == secretPIN) {
            file.close();
            return false; // Found a duplicate secret PIN
        }
    }
    file.close();
    return true; // Secret PIN is unique
}
    int calculateAge(const std::string& dateOfBirth){
    // Get the current time
    std::time_t currentTime = std::time(nullptr);
    std::tm* now = std::localtime(&currentTime);

    // Parse the date of birth
    std::tm dob = {};
    std::istringstream(dateOfBirth.substr(0, 2)) >> dob.tm_mday;
    std::istringstream(dateOfBirth.substr(3, 2)) >> dob.tm_mon;
    std::istringstream(dateOfBirth.substr(6, 4)) >> dob.tm_year;

    // Adjust month and year values
    dob.tm_mon -= 1;  // Month is zero-based
    dob.tm_year -= 1900;  // Years since 1900

    // Calculate the age
    int age = now->tm_year - dob.tm_year;
    if (now->tm_mon < dob.tm_mon || (now->tm_mon == dob.tm_mon && now->tm_mday < dob.tm_mday)) {
        age--;
    }

    return age;
}
}rec[20];
fstream file;
transaction t;
std::set<unsigned int> generatedNumbers; 
void newuser(){
	file.open("AccountNew.txt",ios::app);
	if(!file){
		std::cout<<"Couldn't open";
		exit(1);
	}
	std::cout<<"Enter your name";
	std::cin>>t.name;
	
	std::cout<<"Enter your phone number:";
	cin>>t.phone;
    if(strlen(t.phone)>10){
    	std::cout<<"Invalid number";
    	exit(0);
	}
    
    std::cout<<"Enter your date of birth:";
    std::cin>>t.dob;
    if (t.isValidDate(t.dob)) {
        std::cout << "Valid date." << std::endl;
    } else {
        std::cout << "Invalid date." << std::endl;
        return;
    }
      int Charage = t.calculateAge(t.dob);
     std::ostringstream oss;
        oss << Charage;
        std::string ageStr = oss.str();
         t.age = ageStr.c_str();
    std::cout<<"Your age is:"<<t.age<<"\n";
    std::cout<<"Enter the type of account (e.g., savings, current)\n";
    std::cout<<"s-savings,c-current\n";
    std::cin>>t.type;
    if(t.type=="s"|| t.type=="S"||t.type=="c"||t.type=="C"){
    	if(t.type=="s"||t.type=="S"){
    		std::cout<<"You have opted Saving account!"<<std::endl;
		}
		else{
			std::cout<<"You have opted Current Account!"<<std::endl;
		}
	}
	else{
		std::cout<<"You must opt saving(s) or current(c) account\n";
		return;
	}
    cout<<"Enter your email-Id";
    cin>>t.email;
    if (t.isValidEmail(t.email)) {
        std::cout << "Valid email address." << std::endl;
    } else {
        std::cout << "Invalid email address." << std::endl;
    }
	std::random_device rd;
    std::mt19937 generator(rd());
    std::uniform_int_distribution<unsigned int> dist(111111111111,999999999999);
    unsigned int randomAccNo;
//    unsigned int randomAccNo;
do {
    randomAccNo = dist(generator);
} while (generatedNumbers.count(randomAccNo) > 0 || t.isAccountNumberExist(std::to_string(randomAccNo)));

    generatedNumbers.insert(randomAccNo);

    std::string accNoStr = std::to_string(randomAccNo);
    std::strcpy(t.acc_no, accNoStr.c_str());

    std::cout << "Your Account number is generated: " << t.acc_no << std::endl;
    std::cout << "Enter secret PIN: ";
    std::cin >> t.secretPIN;
 while (!t.isSecretPINUnique("AccountNew.txt", t.secretPIN)) {
        std::cout << "Secret PIN already entered. Please enter a different PIN." << std::endl;
        std::cin >> t.secretPIN;
    }
    std::cout<<"please depoist intial amount!!"<<std::endl;
    std::cout<<"Please make sure that depoist is more than 1000 Rupees."<<std::endl;
    cin>>t.amount;
    if (std::stoi(t.amount) >= 1000) {
        std::strcpy(t.total, t.amount);
    } else {
        std::cout << "Please enter an amount greater than 1000 Rupees." << std::endl;
        return;
    }
    std::cout<<"Account Created Successfully!!"<<std::endl;
     file<<t.acc_no<<"|"<<t.name<<"|"<<t.type<<"|"<<t.dob<<"|"<<t.age<<"|"<<t.phone<<"|"<<t.email<<"|"<<t.total<<"|"<<t.secretPIN<<std::endl;
    file.close();
    
}

void deposit() {
    std::ifstream inputFile("AccountNew.txt");
    std::ofstream outputFile("temp.txt");

    if (!inputFile || !outputFile) {
        std::cout << "Couldn't open the files." << std::endl;
        exit(1);
    }

    std::string acc_number;
    std::cout << "Enter the account number: ";
    std::cin >> acc_number;

    std::string secretPIN;
    std::cout << "Enter the secret PIN: ";
    std::cin >> secretPIN;

    bool accountFound = false;

    std::string line;
    while (std::getline(inputFile, line)) {
        std::istringstream iss(line);
        std::string accNoFromFile;
        std::string name,type, age, phone, email, total,dob, secretPINFromFile;

        std::getline(iss, accNoFromFile, '|');
        std::getline(iss, name, '|');
        std::getline(iss,type,'|');
        std::getline(iss, age, '|');
        std::getline(iss,dob,'|');
        std::getline(iss, phone, '|');
        std::getline(iss, email, '|');
        std::getline(iss, total, '|');
        std::getline(iss, secretPINFromFile, '\n');

        if (accNoFromFile == acc_number && secretPINFromFile == secretPIN) {
            int depositAmount;
            std::cout << "Enter the amount you want to deposit: ";
            std::cin >> depositAmount;

            int currentTotal = std::stoi(total);
            int newTotal = currentTotal + depositAmount;
            total = std::to_string(newTotal);

            accountFound = true;
        }

        outputFile << accNoFromFile << "|" << name << "|"<<type<< "|"<< dob << "|"<<age<<"|"<< phone << "|"
                   << email << "|" << total << "|" << secretPINFromFile << std::endl;
    }
    inputFile.close();
    outputFile.close();

    if (accountFound) {
        std::remove("AccountNew.txt");
        std::rename("temp.txt", "AccountNew.txt");
        std::cout << "Deposit successful." << std::endl;
    } else {
        std::remove("temp.txt");
        std::cout << "Invalid account number or secret PIN." << std::endl;
    }
}

void withdraw() {
    std::ifstream inputFile("AccountNew.txt");
    std::ofstream outputFile("temp.txt");

    if (!inputFile || !outputFile) {
        std::cout << "Couldn't open the files." << std::endl;
        exit(1);
    }

    std::string acc_number;
    std::cout << "Enter the account number: ";
    std::cin >> acc_number;
    std::string secretPIN;
    std::cout<<"Enter the secret pin";
    std::cin>>secretPIN;

    std::string line;
    bool accountFound = false;

    while (std::getline(inputFile, line)) {
        std::istringstream iss(line);
        std::string accNoFromFile;
        std::string name,age,phone,type,email,total,dob,secretPINFromFile;
            std::getline(iss,accNoFromFile,'|');
		    std::getline(iss, name, '|');
            std::getline(iss,type,'|');
            std::getline(iss, age, '|');
            std::getline(iss,dob,'|');
            std::getline(iss, phone, '|');
            std::getline(iss, email, '|');
            std::getline(iss, total, '|');
            std::getline(iss, secretPINFromFile, '\n');

            if (accNoFromFile == acc_number && secretPINFromFile == secretPIN) {
            int withdrawAmount;
            std::cout << "Enter the amount you want to withdraw: ";
            std::cin >> withdrawAmount;

            int currentTotal = std::stoi(total);
            if (withdrawAmount <= currentTotal) {
                int newTotal = currentTotal - withdrawAmount;
                if(newTotal>=1000){
				
				total = std::to_string(newTotal);

                outputFile << accNoFromFile << "|" << name <<"|"<<type<< "|" << dob << "|"<<age<<"|" << phone << "|"
                           << email << "|" << total << "|" << secretPIN << std::endl;

                accountFound = true;
            } 
			else{
				std::cout<<"Your account must have a initial amount of 1000 rupees!";
			}}
			else {
                std::cout << "Insufficient funds." << std::endl;
                outputFile << line << std::endl; // Copy the line as it is to the temporary file
            }
        } else {
            outputFile << line << std::endl; // Copy the line as it is to the temporary file
        }
    }
    inputFile.close();
    outputFile.close();

    if (accountFound) {
        std::remove("AccountNew.txt");         // Remove the original file
        std::rename("temp.txt", "AccountNew.txt"); // Rename the temporary file to the original file name
        std::cout << "Withdrawal successful." << std::endl;
    } else {
        std::remove("temp.txt"); // Remove the temporary file if the account was not found
        std::cout << "Invalid Account number or Secret Pin." << std::endl;
    }
}

void retrieveRecord(const std::string& searchValue) {
    std::ifstream inputFile("AccountNew.txt");

    if (!inputFile) {
        std::cout << "Couldn't open the file." << std::endl;
        return;
    }

    std::string line;
    bool recordFound = false;

    while (std::getline(inputFile, line)) {
        std::istringstream iss(line);
        std::string accNoFromFile;
        std::getline(iss, accNoFromFile, '|');

        if (accNoFromFile == searchValue) {
            std::string name, age, phone,type, email, total,dob, secretPIN;
            std::getline(iss, name, '|');
            std::getline(iss,type,'|');
            std::getline(iss, age, '|');
            std::getline(iss,dob,'|');
            std::getline(iss, phone, '|');
            std::getline(iss, email, '|');
            std::getline(iss, total, '|');
            std::getline(iss, secretPIN, '\n');

            std::cout << "Record found:" << std::endl;
            std::cout<<"\n======Account Number\tName\ttype\tAge\tDOB\t\tPhone Number\t\tEmail-Id\tTotal Balance======";
            
            std::cout <<"\n"<<"       "<<accNoFromFile<<"\t"<<name<<"\t"<<type<<"\t"<<dob<<"\t"<<age<<"\t\t"<<phone<<"\t"<<email<<"\t"<<total;
            
            recordFound = true;
            break; // Stop searching after finding the record
        }
    }
    inputFile.close();

    if (!recordFound) {
        std::cout << "Record not found." << std::endl;
    }
}

void deleteRecord(const std::string& accNumber) {
    std::ifstream inputFile("AccountNew.txt");
    std::ofstream outputFile("temp.txt");

    if (!inputFile || !outputFile) {
        std::cout << "Couldn't open the files." << std::endl;
        return;
    }

    std::string line;
    bool recordFound = false;

    while (std::getline(inputFile, line)) {
        std::istringstream iss(line);
        std::string accNoFromFile;
        std::getline(iss, accNoFromFile, '|');

        if (accNoFromFile == accNumber) {
            // Skip writing this line to the temporary file
            recordFound = true;
        } else {
            // Write the line to the temporary file
            outputFile << line << std::endl;
        }
    }

    inputFile.close();
    outputFile.close();

    if (recordFound) {
        std::remove("AccountNew.txt");         // Remove the original file
        std::rename("temp.txt", "AccountNew.txt"); // Rename the temporary file to the original file name
        std::cout << "Record deleted successfully." << std::endl;
    } else {
        std::remove("temp.txt"); // Remove the temporary file if the record was not found
        std::cout << "Record not found." << std::endl;
    }
}


void updateRecord(const string& accNumber) {
        ifstream inputFile("AccountNew.txt");
        ofstream outputFile("temp.txt");

        if (!inputFile || !outputFile) {
            cout << "Couldn't open the files." << endl;
            return;
        }

        string line;
        bool recordFound = false;

        while (getline(inputFile, line)) {
            istringstream iss(line);
            string accNoFromFile;
            string name, age, phone,type, dob,secretPIN,email,total;

            getline(iss, accNoFromFile, '|');
            getline(iss, name, '|');
            getline(iss,type,'|');
            getline(iss, age, '|');
            getline(iss,dob,'|');
            getline(iss, phone, '|');
            getline(iss, email, '|');
            getline(iss,total,'|');
            getline(iss,secretPIN,'\n');
            if (accNoFromFile == accNumber) {
                // Update the record
                std::cout << "Enter the updated name: ";
                std::cin>>name;

                cout << "Enter the updated phone number: ";
                std::cin>>phone;

                cout << "Enter the updated date of birth (DD/MM/YYYY): ";
                std::cin>>dob;
                if (!t.isValidDate(dob)) {
                    cout << "Invalid date format. Please enter in the format DD/MM/YYYY." << endl;
                    return;
                }
                int Charage = t.calculateAge(dob);
                std::ostringstream oss;
                oss << Charage;
                std::string ageStr = oss.str();
                age = ageStr.c_str();
                std::cout<<"Your age is:"<<age<<"\n";
                cout<<"Enter the updated email";
                std::cin>>email;
                if (!t.isValidEmail(email)){
                	std::cout<<"Invalid format of email.Please enter email with \"@\" in it"<<endl;
                	return;
				}

                recordFound = true;
            }

            outputFile << accNoFromFile << "|" << name<<"|"<<type<< "|"<<dob<<"|" <<age<< "|" << phone << "|"<<email<<'|'
                       << total << "|"<<secretPIN<<"\n";
        }

        inputFile.close();
        outputFile.close();

        if (recordFound) {
            remove("AccountNew.txt");             // Remove the original file
            rename("temp.txt", "AccountNew.txt"); // Rename the temporary file to the original file name
            cout << "Record updated successfully." << endl;
        } else {
            remove("temp.txt"); // Remove the temporary file
            cout << "Record not found." << endl;
        }
    }
void displayRecords() {
    std::ifstream inputFile("AccountNew.txt");

    if (!inputFile) {
        std::cout << "Couldn't open the file." << std::endl;
        return;
    }

    std::string line;
    int recordCount = 0;
    std::cout<<"\nAcc_No\t\tName\tType\tDOB\t\tAge\tPhone\t\tEmail\t\tBalance"<<std::endl;
    while (std::getline(inputFile, line)) {
        std::istringstream iss(line);
        std::string field;
        int fieldCount = 0;
        
        while (std::getline(iss, field, '|')) {
            ++fieldCount;
            if (fieldCount < 9) {
                std::cout << field << "\t";
            }
        }

        std::cout << std::endl;
        ++recordCount;
    }

    inputFile.close();
}

int main() {
    int ch;
    while (1) {
    	std::cout<<"\n-------------------------------------------------------------------------------\n";
    	std::cout<<"\n=============================WELCOME TO YOUR BANK==============================\n";
    	std::cout<<"\n-------------------------------------------------------------------------------\n";
    	std::cout<<"Our services provided are...\n";
    	std::cout<<"1.Create an account\n";
    	std::cout<<"2.Deposit amount\n";
    	std::cout<<"3.Withdraw amount\n";
    	std::cout<<"4.Balance Enquiry\n";
    	std::cout<<"5.Delete Recordn\n";
    	std::cout<<"6.Update Record\n";
    	std::cout<<"7.Display All\n";
        std::cout <<"\nEnter your choice:";
        std::cin >> ch;
 
        switch (ch) {
            case 1:
                newuser();
                break;
            case 2:
                deposit();
                break;
            case 3:
			    withdraw();
            	break;
            case 4: {
                std::string searchValue;
                std::cout << "Enter the account number to retrieve the record: ";
                std::cin >> searchValue;
                retrieveRecord(searchValue);
                break;
            }
            case 5:{
            	std::string adminid;
            	std::string pass;
            	std::cout<<"Enter the Admin-Id";
            	std::cin>>adminid;
            	std::cout<<"Enter the admin password";
            	std::cin>>pass;
            	if(pass==t.password && adminid==t.admin_id){
            	 std::string acc;
                 std::cout << "Enter the account number to delete the record: ";
                 std::cin >> acc;
                 deleteRecord(acc);}
                 else
                 std::cout<<"The password is wrong";
                 break;
				 }
			case 6:{
				std::string adminid;
            	std::string pass;
            	std::cout<<"Enter the Admin-Id";
            	std::cin>>adminid;
            	std::cout<<"Enter the admin password";
            	std::cin>>pass;
            	if(pass==t.password && adminid==t.admin_id){
				std::string accNumber;

             std::cout << "Enter the account number of the record to update: ";
            std::cin>>accNumber;

    if (!t.isAccountNumberExist(accNumber)) {
        std::cout << "Record not found." << std::endl;
        return 0;
    }
    updateRecord(accNumber);
break;
}}
            case 7:{
				std::string adminid;
            	std::string pass;
            	std::cout<<"Enter the Admin-Id";
            	std::cin>>adminid;
            	std::cout<<"Enter the admin password";
            	std::cin>>pass;
            	if(pass==t.password && adminid==t.admin_id){
            	displayRecords();}
            	else{
            		std::cout<<"Wrong Admin ID or Password"<<std::endl;
				}
            	break;}
            case 8:
                return 0; 
            default:
                cout << "Invalid choice. Please try again.\n" << endl;
                break;
        }
    }
    return 0;
}