Pixel Pairs (Android Memory Card Matching Game)

An Android application where users fetch images from the web and play a memory card matching game. Built with Kotlin (Android) and ASP.NET Core (.NET backend). Developed in collaboration with the team.

Features

• User Authentication -- Login system backed by a MySQL database via .NET REST API.
• Image Fetching -- Enter a URL (e.g. StockSnap.io) to scrape and download up to 20 images, displayed in a grid with a progress bar.
• Image Selection -- Select exactly 6 images from the fetched results to use as card faces.
• Memory Card Game -- A 3x4 grid card-matching game with flip animations, timer, and pause/resume functionality.
• Leaderboard -- Completion times are submitted as scores; top 5 players are displayed.
• Ad Support -- Free-tier users see ads during gameplay; paid users do not.
• Background Music -- Music service plays during login and gameplay.

Tech Stack

Layer	Technology
Android	Kotlin, Coroutines, View Binding, Glide, OkHttp, Jsoup
Backend	ASP.NET Core (.NET 10), MySQL, MySqlConnector
Architecture	Activities + Fragments, REST API, MVC

Screenshots

In order:

1. Login
2. Image fetch screen
3. Mid fetch
4. Fetch completed, select 6 images to play
5. First pair that matches
6. All pairs matched, game completed.
7. Leaderboard with play button that goes back to fetch

Prerequisites

• Android Studio (Arctic Fox or later)
• .NET 10 SDK
• MySQL Server (e.g. MySQL 8.x)
• Android Emulator or physical device (min SDK 29 / Android 10)

How to Run

1. Database Setup

1. Install and start MySQL Server.
2. Create the database and required tables:

CREATE DATABASE AndroidCA;
USE AndroidCA;

CREATE TABLE Users (
    Username VARCHAR(255) PRIMARY KEY,
    Password VARCHAR(255) NOT NULL
);

CREATE TABLE UserDetails (
    Id BIGINT AUTO_INCREMENT PRIMARY KEY,
    Username VARCHAR(255) NOT NULL,
    UserType VARCHAR(50) NOT NULL
);

CREATE TABLE Scores (
    Id BIGINT AUTO_INCREMENT PRIMARY KEY,
    UserDetailId BIGINT NOT NULL,
    Score BIGINT NOT NULL,
    FOREIGN KEY (UserDetailId) REFERENCES UserDetails(Id)
);

3. Insert sample users:

INSERT INTO Users (Username, Password) VALUES ('player1', 'password123');
INSERT INTO UserDetails (Username, UserType) VALUES ('player1', 'Free');

INSERT INTO Users (Username, Password) VALUES ('player2', 'password123');
INSERT INTO UserDetails (Username, UserType) VALUES ('player2', 'Paid');

2. Backend (.NET API)

1. Open a terminal in the DotNetBackend/DotNetBackend/ directory.
2. Update the connection string in Data/Constants.cs with your MySQL credentials:
public static string CONNECTION_STRING = @"server=localhost;uid=root;pwd=YOUR_PASSWORD;database=AndroidCA";
3. Run the backend:
dotnet run
4. The API will start on http://localhost:5119. Verify by visiting http://localhost:5119/api/scores/leaderboard.
5. Start my SQL DB as necessary.

3. Android App

1. Open the android/ folder in Android Studio.
2. Wait for Gradle sync to complete.
3. If using the Android Emulator, the backend URL http://10.0.2.2:5119 (already configured) maps to your host
machine's localhost:5119.
  - If using a physical device, update the base URL in LoginActivity.kt to your machine's local IP (e.g.
http://192.168.x.x:5119).
4. Run the app on the emulator or device (min API 29).

4. Using the App

1. Log in with a valid username and password. For testing purposes: (johndoe, 12345)
2. Enter a StockSnap.io URL (e.g. https://stocksnap.io/search/nature) in the fetch screen.
3. Wait for up to 20 images to load.
4. Tap to select exactly 6 images, then press Start Playing.
5. Match all 6 pairs as fast as possible -- your time is your score!

Project Structure

android/                # Android application (Kotlin)
  adapters/             # ImageAdapter, CardAdapter, LeaderboardAdapter
  fragments/            # LeaderboardFragment, LoadingFragment
  models/               # ImageItem, LeaderboardEntry, Users
  services/             # MusicService
  FetchActivity.kt      # Fetch images from URL
  PlayActivity.kt       # Memory card matching game
  LoginActivity.kt      # User authentication
  LeaderboardActivity.kt

DotNetBackend/          # .NET backend API
  Controllers/          # AuthController, ScoresController
  Models/               # Score, Leaderboard DTOs
  Data/                 # ScoresDAO, Constants (DB connection)

API Endpoints

┌────────┬─────────────────────────────┬─────────────────────────┐
│ Method │          Endpoint           │       Description       │
├────────┼─────────────────────────────┼─────────────────────────┤
│ POST   │ /api/auth/login             │ Authenticate user       │
├────────┼─────────────────────────────┼─────────────────────────┤
│ POST   │ /api/scores/submit          │ Submit a game score     │
├────────┼─────────────────────────────┼─────────────────────────┤
│ GET    │ /api/scores/leaderboard     │ Get top 5 scores        │
├────────┼─────────────────────────────┼─────────────────────────┤
│ GET    │ /api/scores/user/{username} │ Get a user's best score │
└────────┴─────────────────────────────┴─────────────────────────┘