AyBay

A powerful and lightweight Android application for tracking income, expenses, budgets, savings, loans, and more.

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Features

• Comprehensive Tracking: Track income, expenses, savings, budgets, and loans/debts.
• Smart AI Assistant: "Walleo" - Built-in AI chatbot for personalized financial guidance and suggestions.
• Data Visualization: View clean statistics to understand your financial health.
• Search & Filter: Easily find transactions by date, type, or specific queries.
• Backup & Restore: Secure cloud backup via Google Drive and local storage options.
• Offline First: Fully functional offline with robust SQLite local storage.
• Modern UI: Clean, fast, and responsive user interface.

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Installation

You can install AyBay from:

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Architecture & Design Patterns

AyBay is built using a Pattern-Oriented MVC Architecture, leveraging standard GoF design patterns to ensure scalability, maintainability, and clean code.

Data Flow Diagram

graph TD
    subgraph "UI Layer"
        UI_Trans[Transaction Activities]
        UI_Auth[Login/Signup Activities]
        UI_Chat[Walleo Chatbot]
    end

    subgraph "Facade Layer"
        FinMgr[FinanceManager]
        AuthMgr[AuthFacade]
    end

    subgraph "Repository / Strategy Layer"
        Repo[DatabaseRepository]
        Strategy[Expense/Income Strategy]
    end

    subgraph "Business Logic / Patterns"
        Command[DeleteCommand]
        Memento[TransactionMemento]
        Observer[TransactionObserver]
        Factory[TransactionFactory]
    end

    subgraph "Data Layer"
        DB[DatabaseHelper]
        ExtAPI[Gemini API]
    end

    %% Transaction Flow
    UI_Trans -->|Calls| FinMgr
    FinMgr -->|Delegates to| Repo
    Repo -->|Uses| Strategy
    Strategy -->|Persists Insert Update| DB

    FinMgr -->|Executes| Command
    FinMgr -->|Uses| Factory
    FinMgr -->|Registers| Observer

    Command -->|Uses| Memento
    Command -->|Modifies Delete Restore| DB

    DB -->|Notifies| Observer
    Observer -->|Updates| UI_Trans

    %% Authentication Flow
    UI_Auth -->|Calls| AuthMgr
    AuthMgr -->|Queries/Updates| DB

    %% Chatbot Flow
    UI_Chat -->|Streams| ExtAPI
    UI_Chat -->|Saves History| DB

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Implemented Patterns:

• Facade Pattern: FinanceManager acts as a unified interface to the complex subsystem of data repositories and logic.
• Strategy Pattern: DataOperationStrategy interfaces with concrete implementations like ExpenseOperationStrategy and IncomeOperationStrategy to handle different transaction types dynamically.
• Observer Pattern: TransactionObserver allows the UI (ShowExpense, ShowIncome) to react automatically to data changes in the repository.
• Command Pattern: DeleteCommand encapsulates delete requests, enabling features like Undo operations.
• Composite Pattern: CategoryComposite treats individual transactions and groups of categories uniformly for calculating totals.
• Iterator Pattern: TransactionIterator provides a standard way to traverse collections of transactions without exposing underlying representations.
• Factory Pattern: TransactionFactory handles the creation of complex Transaction objects.
• Adapter Pattern: CurrencyAdapter and DateAdapter transform data formats to be compatible with UI requirements.
• Memento Pattern: Support for capturing and restoring object state (e.g., for Undo functionality).
• Singleton Pattern: Ensures crucial classes like FinanceManager and DatabaseHelper have a single shared instance.

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Built With

• Language: Java (Android SDK)
• Database: SQLite (Custom DatabaseHelper)
• Testing: JUnit 5, Mockito
• Networking: OkHttp (for AI Chatbot)

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Screenshots

   

   

   

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⚠️ Disclaimer

This app is for educational and personal finance management purposes only.
It is not associated with any banking or financial institution.