BitBuilders Invoice System (GUI Edition)

A professional and modular invoice generator built for the BitBuilders Fun Code Race.

Key Features

• Graphical User Interface (GUI): An intuitive window built with Tkinter for easy data entry.
• Multi-Currency Support: Switch between USD and MXN with automatic exchange rate handling.
• Smart Discount Logic: Automatically applies a 10% discount on orders over $500.
• File Persistence: Exports every invoice as a formatted .txt file with unique timestamps.

Project Architecture

The system follows the Single Responsibility Principle (SRP):

• invoice_manager.py: The "Brain". Handles all math, taxes, and discounts.
• exporter.py: The "Writer". Formats and saves the data to the disk.
• main.py: The "Face". Reuses the logic to provide a visual experience.

How to Run

1. Ensure you have Python 3 installed.
2. (Linux only) Install Tkinter: sudo apt-get install python3-tk
3. Run the GUI:

   python main.py