Bank Management System (C++)

Project Overview

This project is a robust Bank Management System implemented in C++. It utilizes Object-Oriented Programming (OOP) principles to provide a secure and structured environment for managing bank clients, users, and financial transactions. The system includes advanced features such as user access control, data persistence, and a dedicated currency exchange service.

The primary goal of this system is to offer a comprehensive solution for bank operations, including client account management (deposit, withdrawal, transfer), user administration, and detailed logging of system activities.

Key Features

The system is designed with a rich set of functionalities to cover essential banking and administrative tasks:

Feature Category	Features	Description
Client Management	Client List, Add New Client, Update Client, Delete Client, Find Client	Full CRUD (Create, Read, Update, Delete) operations for managing bank client records.
Transactions	Deposit, Withdraw, Transfer, Total Balance	Core financial operations, including inter-account transfers and calculation of the total bank balance.
User Administration	User List, Add New User, Update User, Delete User, Find User	Full CRUD operations for managing system users with different access levels.
Security & Logging	Secure Login, Access Permissions, Login Register, Transfer Log	Implements a robust security model with encrypted passwords, granular permissions, and detailed logging of all login attempts and financial transfers.
Currency Exchange	Currencies List, Find Currency, Update Rate, Currency Calculator	A dedicated module for managing currency exchange rates and performing conversions between different currencies.

Object-Oriented Programming (OOP) Implementation

The project is built upon a strong OOP foundation, leveraging key principles to ensure code reusability, maintainability, and logical separation of concerns.

1. Inheritance

The system employs a clear inheritance hierarchy, starting with a base class for common attributes:

Base Class	Derived Classes	Description
clsPerson	clsBankClient, clsUser	clsPerson serves as the base class, encapsulating common personal details (FirstName, LastName, Email, Phone). Both clsBankClient and clsUser inherit these properties, promoting code reuse.

2. Encapsulation

All class data members are declared as private (e.g., _FirstName, _Password, _AccountBalance). Access and modification are strictly controlled through public methods (SetFirstName(), GetFirstName()) and C++ property wrappers (__declspec(property)) where applicable, ensuring data integrity.

3. Abstraction

The system uses abstraction to hide complex file handling and data conversion logic from the main application flow.

• Data Persistence: Private static methods like _LoadUsersDataFromFile() and _ConvertLineToUserObject() handle the intricate details of reading from and writing to text files (Users.txt, Clients.txt, etc.).
• Business Logic: Public methods like Save(), Delete(), Deposit(), and Transfer() provide a simple, clean interface for the user and client management screens, abstracting away the underlying file I/O and data validation.

Advanced System Modules

1. Access Permissions and Control

User access is managed through a comprehensive permissions system, ensuring that only authorized users can perform specific actions.

• Permission Enumeration: An enum enPermissions in clsUser defines distinct access rights using bitwise flags (e.g., pShowClientsList = 1, pAddNewClient = 2, pManageUsers = 64).
• Bitwise Permissions: Each user is assigned a single integer value (_Permission) which is a sum of their allowed permissions. The CheckAccessPermission() method uses bitwise AND (&) to efficiently verify if a user has a specific right.
• Administrator Access: The eAll permission (-1 or all bits set) grants full administrative control.

2. Data Persistence and Logging

The system maintains data integrity and audit trails by persisting all critical information to dedicated text files.

Log File	Purpose	Key Data Points
Users.txt	Stores all system user accounts.	Encrypted Password, Permission Level.
Clients.txt	Stores all bank client accounts.	Account Number, PIN Code, Account Balance.
LoginRegister.txt	Login Persistence	Logs every successful login attempt with Date and Time, Username, and Permission Level.
TransferLog.txt	Transaction Logging	Records every money transfer with Date and Time, Source/Destination Account Numbers, Transfer Amount, and the Responsible User's Name.

3. Currency Exchange Service

A dedicated clsCurrency class manages currency data and facilitates exchange operations.

• Currency Management: Allows listing, finding, and updating the exchange rate for any currency.
• Conversion Logic: The class provides methods to convert any amount to USD (ExchangeToUSD()) and then from USD to any other currency (ExchangeToOtherCurrency()), ensuring a standardized conversion pipeline.

4. User and Client Management Operations

The system provides robust methods for managing both system users and bank clients:

• Add/Update/Delete Client: Handled by the clsBankClient class, using internal file manipulation methods (_AddNew(), _Update(), Delete()) to ensure data consistency.
• Add/Update/Delete User: Handled by the clsUser class, with similar internal file management logic. Passwords are encrypted before being stored in Users.txt using clsUtil::TextEncryption().

Project Structure

The project is organized into logical directories for clarity and maintainability:

.
├── Core/
│   ├── clsBankClient.h
│   ├── clsCurrency.h
│   ├── clsPerson.h
│   └── clsUser.h
├── Lib/
│   ├── clsDate.h
│   ├── clsInputValidate.h
│   ├── clsString.h
│   └── clsUtil.h
├── Screens/
│   ├── Client/
│   ├── Currencies/
│   ├── User/
│   ├── clsMainScreen.h
│   └── clsScreen.h
├── txt files/ (Data Files)
│   ├── Clients.txt
│   ├── Currencies.txt
│   ├── LoginRegister.txt
│   ├── TransferLog.txt
│   └── Users.txt
└── RunProject.cpp (Main execution file)

Technologies Used

• Language: C++
• Data Storage: Flat File System (Text Files)

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