🏦 NexusBank-CLI

A robust, dual-application core banking system simulation built entirely in C++20.

---

📖 Overview

NexusBank-CLI is a complete banking system simulation consisting of two standalone console applications that work together:

Application	Purpose	Target User
NexusBank Manager	Administrative operations and client management	Bank Staff / Administrators
NexusBank ATM	Self-service banking transactions	Bank Clients

Both applications share a common flat-file database (Data/), enabling seamless data persistence and real-time synchronization between staff and client operations.

---

✨ Features

🖥️ NexusBank Manager (Admin Panel)

Category	Features
Client Management	Full CRUD operations: List, Add, Update, Delete, and Find clients
User Management	Manage system users with granular permission controls
Permissions System	Bitwise permission flags (List, Add, Delete, Update, Find, Transactions, Manage Users)
Transactions	Process deposits, withdrawals, and view total bank balances
Security	Role-based access control with login authentication

🏧 NexusBank ATM (Client Self-Service)

Feature	Description
Quick Withdraw	Pre-set withdrawal amounts ($20, $50, $100, $200, $400, $600, $800, $1000)
Normal Withdraw	Custom withdrawal amounts (multiples of 5)
Deposit	Add funds to account balance
Balance Inquiry	View current account balance
Secure Login	Account Number + PIN authentication

---

🛠️ Tech Stack

Technology	Usage
C++20	Core language standard
STL Containers	std::vector for in-memory data processing
File I/O	std::fstream for persistent storage
Modular Design	Procedural architecture with clearly separated concerns

Architecture Highlights

• Custom Serialization/Deserialization — Records are converted to/from delimited strings
• In-Memory Processing — Data loaded into vectors for efficient manipulation
• Flat-File Database — Human-readable .txt files with custom delimiter

---

📁 Data Format

The system uses a custom flat-file database with #//# as the field delimiter.

Data/Clients.txt

AccountNumber#//#PinCode#//#Name#//#Phone#//#Balance

Example:

A001#//#1234#//#John Doe#//#555-0100#//#5000.00
A002#//#5678#//#Jane Smith#//#555-0200#//#12500.50

Data/Users.txt

Username#//#Password#//#Permissions

Example:

Admin#//#Admin#//#-1
Teller01#//#pass123#//#35

Note: Permission value -1 grants full access. Other values use bitwise flags: 1 = List Clients | 2 = Add Client | 4 = Delete Client | 8 = Update Client | 16 = Find Client | 32 = Transactions | 64 = Manage Users

---

🚀 Setup & Compilation

Prerequisites

• C++20 compatible compiler (GCC 10+, Clang 10+, or MSVC 2019+)
• Windows OS (uses system("cls") and system("pause"))

Option 1: Visual Studio (Recommended for Windows)

1. Open NexusBank_CLI/NexusBank_CLI.slnx or NexusBank_ATM/NexusBank_ATM.slnx
2. Set configuration to Debug or Release
3. Build the solution (Ctrl+Shift+B)
4. Run with F5 or Ctrl+F5

Important: Ensure the Data folder is located two levels up from the executable (..\..\Data\).

Option 2: Command Line (g++)

# Compile NexusBank Manager
g++ -std=c++20 -o NexusBank_Manager.exe NexusBank_CLI/NexusBank_CLI.cpp

# Compile NexusBank ATM
g++ -std=c++20 -o NexusBank_ATM.exe NexusBank_ATM/NexusBank_ATM.cpp

Option 3: Command Line (MSVC)

:: Compile NexusBank Manager
cl /std:c++20 /EHsc NexusBank_CLI\NexusBank_CLI.cpp /Fe:NexusBank_Manager.exe

:: Compile NexusBank ATM
cl /std:c++20 /EHsc NexusBank_ATM\NexusBank_ATM.cpp /Fe:NexusBank_ATM.exe

---

🔐 Default Credentials

Application	Username/Account	Password/PIN
Manager	Admin	Admin
ATM	Admin	Admin

---

📂 Project Structure

NexusBank-CLI/
├── Data/
│   ├── Clients.txt          # Client database
│   └── Users.txt            # User/admin database
├── NexusBank_ATM/
│   ├── NexusBank_ATM.cpp    # ATM application source
│   └── *.vcxproj            # Visual Studio project files
├── NexusBank_CLI/
│   ├── NexusBank_CLI.cpp    # Manager application source
│   └── *.vcxproj            # Visual Studio project files
└── README.md

---

📄 License

This project is available for educational purposes.

---

NexusBank-CLI — Banking made simple. 💳