TREZZA TERMINAL - Point of Sale (GPUI)

A modern, high-performance point of sale system built with Rust, GPUI, and PostgreSQL.

🚀 Features

• Modern UI: Built with GPUI for native performance and beautiful design
• Full-Stack Rust: Frontend (GPUI), Backend (Axum), and Shared types
• Real-time Inventory: Track stock levels with automatic reordering alerts
• Authentication: Secure JWT-based authentication for employees
• Order Management: Complete order lifecycle from cart to completion
• Receipt Printing: Generate professional receipts
• Database Migrations: Automated PostgreSQL schema management
• RESTful API: Clean API design with comprehensive endpoints

📦 Architecture

trezza-terminal/
├── frontend/          # GPUI-based desktop application
│   ├── src/
│   │   ├── main.rs    # Main UI and application logic
│   │   ├── api.rs     # API client for backend communication
│   │   ├── state.rs   # Application state management
│   │   └── receipt.rs # Receipt generation and printing
│   └── Cargo.toml
├── backend/           # Axum web server
│   ├── src/
│   │   ├── main.rs    # Server setup and routing
│   │   ├── auth.rs    # Authentication logic
│   │   ├── config.rs  # Configuration management
│   │   ├── db/        # Database models and queries
│   │   ├── routes/    # API route handlers
│   │   └── services/  # Business logic
│   ├── migrations/    # SQL migration files
│   └── Cargo.toml
└── shared/            # Shared types and utilities
    ├── src/
    │   ├── types.rs   # Common data structures
    │   ├── errors.rs  # Error types
    │   └── constants.rs
    └── Cargo.toml

🛠️ Setup

Prerequisites

• Rust (latest stable)
• PostgreSQL 14+
• Git

Database Setup

1. Install PostgreSQL and create a database:

createdb trezza_terminal

2. Copy the example environment file:

cd backend
cp .env.example .env

3. Edit .env and update the DATABASE_URL with your PostgreSQL credentials.

Running the Application

Terminal 1 - Backend Server

cd backend
cargo run --bin trezza-terminal-server

The server will:

• Run migrations automatically
• Start on http://127.0.0.1:3000
• Seed the database with sample data

Default admin credentials:

• Username: admin
• Password: admin123

Terminal 2 - Frontend Application

cd frontend
cargo run --bin trezza-terminal

📡 API Endpoints

Authentication

• POST /api/auth/login - User login

Products

• GET /api/products - List all products
• GET /api/products/:id - Get product by ID
• GET /api/products/search?q=query - Search products

Orders

• POST /api/orders - Create new order (requires auth)
• GET /api/orders/:id - Get order details
• POST /api/orders/:id/complete - Complete order (requires auth)
• POST /api/orders/:id/cancel - Cancel order (requires auth)

Inventory

• GET /api/inventory/:product_id - Get inventory for product
• GET /api/inventory/low-stock - Get low stock items
• POST /api/inventory/:product_id/restock - Restock product

🧪 Testing

Run all tests:

# Shared library tests
cd shared && cargo test

# Backend tests
cd backend && cargo test

# Frontend tests (when available)
cd frontend && cargo test

🎨 UI Features

• Product Catalog: Grid view with category filtering
• Shopping Cart: Real-time cart updates with add/remove
• Payment Processing: Multiple payment methods
• Receipt Generation: Automatic receipt creation and printing
• Error Handling: User-friendly error messages
• Loading States: Visual feedback for async operations

🔒 Security

• JWT-based authentication
• Password hashing (production-ready with bcrypt/argon2)
• SQL injection protection via SQLx
• CORS configuration
• Input validation

📊 Database Schema

The system includes comprehensive tables for:

• Users (employees with role-based access)
• Products and Categories
• Inventory tracking
• Orders and Order Items
• Sessions
• Audit Logs

See backend/migrations/ for the full schema.

🎯 Development Roadmap

• Add barcode scanning support
• Implement customer loyalty program
• Add sales analytics dashboard
• Multi-location support
• Mobile companion app
• Cloud backup and sync

📝 License

Copyright © 2025 TREZZA TERMINAL

🤝 Contributing

This is a private project. For questions or issues, contact the development team.

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Built with ❤️ using Rust, GPUI, Axum, and PostgreSQL