🍕 LazyPizza - Modern Pizza Ordering Android App

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• 繁體中文 (Traditional Chinese)
• 日本語 (Japanese)

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LazyPizza is a modern, high-performance pizza ordering application for Android built to showcase production-ready mobile development best practices. Adopting Clean Architecture, MVI/MVVM design patterns, Jetpack Compose (Material 3), and an Offline-First sync strategy, LazyPizza provides a beautiful, fluid, and robust user experience.

Important

This application leverages Firebase Services heavily as its serverless backend, integrating authentication, cloud database, asset storage, and cloud messaging systems into a cohesive real-time mobile experience.

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📸 Screenshots

🔑 Login	💬 Phone Sign-In	🍕 Menu

🛒 Order Menu	🔎 Product Details	🛍 Shopping Cart

📅 Date Picker	🕒 Time Picker	🎉 Order Placed

📜 Order History	🔔 Push Notification

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🔥 Heavy Firebase Integration

This project is built serverless, utilizing a suite of Firebase services to manage identity, data, media assets, and push messaging:

• 🔒 Firebase Authentication (Credential Manager API)
  • Frictionless Google Sign-In with modern CredentialManager.
  • SMS OTP login for phone numbers, utilizing Google's libphonenumber library for client-side formatting and international standards.
  • Support for guest checkout via Anonymous Authentication.
• 🗄️ Firebase Firestore (Cloud NoSQL)
  • Serves as the primary cloud database hosting categories, pizza menus, toppings, and order histories.
  • Enables Offline-First Synchronization by caching all incoming Firestore documents in Room DB, automatically resolving merge conflicts when the device goes back online.
• 📁 Firebase Cloud Storage
  • Stores and dynamically streams high-resolution product and topping cover images, which are efficiently cached locally via Coil 3.
• 🔔 Firebase Cloud Messaging (FCM)
  • Receives real-time push notifications regarding order status updates.
  • Integrates with Android's system notification channels, providing custom deep-link entry points directly into the app (lazypizza://history).

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✨ Features

• 🔐 Unified Login
  • Seamless identity management with Google Sign-In, Firebase SMS Verification, and guest access.
• 📦 Offline-First Synchronization
  • Robust local persistence ensuring the menu, toppings, and past orders are accessible and interactable even when offline.
• 🍕 Rich Product Customization & Ordering
  • Dynamic sizing and extra topping configurations with immediate UI state and pricing calculations.
• 📅 Custom Delivery/Pickup Scheduling
  • Highly polished, custom drumroll wheel pickers for Date and Time selections.
• 🔔 Deep Linking Route Dispatcher
  • Allows direct routing to products (lazypizza://product/{pizzaId}) or history (lazypizza://history) from push notification clicks or web URLs.

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🛠 Tech Stack

• UI/Presentation:
  • Jetpack Compose: Declarative UI layout framework.
  • Material 3 (1.5.0-alpha21): Modern styling tokens and dynamic theme behaviors.
  • Coil 3 (3.4.0): Asynchronous image loader utilizing OkHttp network caching.
  • Navigation Compose (2.9.8): Strictly Type-Safe navigation utilizing Kotlin Serialization.
• Dependency Injection & State Control:
  • Koin (4.0.2): Pragmatic, lightweight dependency injection framework.
  • Kotlinx Coroutines & Flow: Reactive streams for state propagation and structured concurrency.
• Data & Network Core:
  • Room Database (2.7.0): SQLite abstraction layer with KSP compiler code generation.
  • Preferences DataStore (1.1.2): Secure, asynchronous local preference caching.
  • Firebase SDK: Auth (SMS/Google), Firestore (NoSQL Db), Cloud Storage, Cloud Messaging (FCM).

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🏗 Architecture & Codebase Design

The project strictly follows Clean Architecture principles and divides concerns into three main layers:

graph TD
    UI[Presentation Layer: Compose, ViewModels, States] --> Domain[Domain Layer: Entities, Use Cases, Interfaces]
    Data[Data Layer: Repositories, DAOs, Firestore DataSources] --> Domain

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• Domain Layer: Pure Kotlin layer containing business rules, entities (Product, Order), and repository interfaces. Completely independent of Android frameworks.
• Data Layer: Responsible for retrieving and storing data. Implements the repository interfaces by orchestrating the Room local database and the Firebase Remote DataSource.
• Presentation Layer: Composed of Jetpack Compose components. Uses the MVI/MVVM pattern where ViewModels process Actions and expose UiStates through unidirectional flows.

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🚀 Getting Started

Prerequisites

• Android Studio Ladybug (2024.2.1) or newer.
• JDK 17.
• A Firebase project.

Configuration Steps

1. Firebase Integration:

   • Create a project in the Firebase Console.
   • Add an Android app with package name com.lihan.lazypizza.
   • Download the google-services.json file and place it in the app/ directory.
   • Enable Phone Authentication and Google Sign-In in the Firebase Auth settings.

2. Google Cloud Console Setup:

   • In the Google Cloud Console corresponding to your Firebase project, copy the Web client ID (under APIs & Services -> Credentials -> OAuth 2.0 Client IDs).
   • Add this value into your project resources: app/src/main/res/values/strings.xml (or map to default_web_client_id).

3. Local SHA-1 Registration:

   • Generate your local debug key SHA-1:

     ./gradlew signingReport

   • Add the outputted SHA-1 and SHA-256 fingerprints to your Firebase/Google Developer Console app settings.

4. Run the Project:

   • Sync Gradle and run the :app configuration on your emulator or physical device.

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📝 License

This project is licensed under the MIT License - see the LICENSE file for details.