💰 Expense Tracker

A modern, Splitwise-like expense tracker built with React. Track expenses, split bills with friends, and manage balances with a beautiful, responsive interface.

✨ Features

• 📊 Dashboard Overview - See your balance and recent activity at a glance
• 👥 Friend Management - Add and manage friends with individual balance tracking
• 💰 Expense Tracking - Add expenses with categories and detailed descriptions
• ⚖️ Smart Splitting - Split expenses equally or with custom amounts
• 📱 Responsive Design - Works perfectly on desktop and mobile devices
• 💾 Local Storage - Your data is saved locally in your browser
• 🎨 Modern UI - Beautiful gradient design with smooth animations

🚀 Getting Started

Prerequisites

• Node.js (version 14 or higher)
• npm or yarn
• Supabase account (free)

Installation

1. Install dependencies:

   npm install

2. Set up Supabase backend:

   • Follow the complete setup guide in SUPABASE_SETUP.md
   • Create a Supabase project
   • Run the database schema
   • Configure environment variables

3. Start the development server:

   npm run dev

4. Open your browser: Navigate to http://localhost:3000 to see the app in action!

📱 How to Use

Adding Friends

1. Click "Manage Friends" from the dashboard
2. Click "Add Friend" and enter their name
3. Friends will appear in your friends list with their current balance

Adding Expenses

1. Click "Add Expense" from the dashboard
2. Fill in the expense details:
   • Description: What the expense was for
   • Amount: The total cost
   • Date: When the expense occurred
   • Category: Choose from predefined categories
   • Paid by: Who paid for this expense
   • Split with: Select who should split this expense
3. Choose split type:
   • Equal Split: Automatically divides the amount equally
   • Custom Amounts: Manually specify how much each person pays
4. Click "Add Expense" to save

Viewing Balances

• Dashboard: See your personal balance and recent expenses
• Balances Tab: View all friends' balances
• Friends Page: Detailed view of each friend's balance

Creating Groups

1. Click "Groups" from the dashboard
2. Click "Create Group"
3. Add group name, description, and select members
4. Groups help organize expenses with specific people

🛠️ Built With

• React 18 - Modern React with hooks
• React Router - Client-side routing
• Vite - Fast build tool and dev server
• Supabase - Backend as a Service (Database, Auth, Real-time)
• Lucide React - Beautiful icons
• Date-fns - Date formatting utilities
• CSS3 - Custom styling with gradients and animations

📁 Project Structure

src/
├── components/
│   ├── Dashboard.jsx      # Main dashboard with overview
│   ├── AddExpense.jsx     # Expense creation form
│   ├── Friends.jsx        # Friend management
│   └── Groups.jsx         # Group management
├── App.jsx               # Main app with routing and state
├── main.jsx              # React entry point
└── index.css             # Global styles

🎯 Key Features Explained

Multi-User Authentication

• Email/Password - Traditional signup and login
• Google OAuth - One-click sign in with Google
• Secure Sessions - JWT-based authentication with Supabase

Real-Time Data Sync

• Live Updates - Changes appear instantly across all users
• Offline Support - Works even when temporarily offline
• Conflict Resolution - Handles simultaneous edits gracefully

Balance Calculation

The app automatically calculates balances by:

1. Adding the full expense amount to who paid
2. Subtracting each person's share from their balance
3. Positive balance = you're owed money
4. Negative balance = you owe money

Smart Splitting

• Equal Split: Automatically divides the total by the number of people
• Custom Split: Manually specify amounts, with validation to ensure they add up to the total

Data Security

• Row Level Security (RLS) - Users can only access their own data
• Friend Relationships - Share expenses only with approved friends
• Encrypted Storage - All data is encrypted at rest

🎨 Design Features

• Gradient Background: Beautiful purple gradient theme
• Card-based Layout: Clean, organized information display
• Responsive Design: Works on all screen sizes
• Smooth Animations: Hover effects and transitions
• Color-coded Balances: Green for positive, red for negative balances

🔧 Development

Available Scripts

• npm run dev - Start development server
• npm run build - Build for production
• npm run preview - Preview production build

Adding New Features

The app is built with a modular component structure, making it easy to add new features:

1. Create new components in src/components/
2. Add routes in App.jsx
3. Update state management as needed
4. Add styles to index.css

🤝 Contributing

Feel free to fork this project and add your own features! Some ideas:

• Export expenses to CSV
• Multiple currency support
• Expense categories with icons
• Recurring expenses
• Payment tracking

📄 License

This project is open source and available under the MIT License.

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Happy expense tracking! 💰 "# Expense_tracker"