Resolve "Example connection to frontend"

backend/src/index.ts

@@ -26,7 +26,6 @@ app.listen(port, '0.0.0.0', () => {
   console.log(`Server started on port ${port}`);
 });
 
-
 // establish connection to firebase
 const admin = require('firebase-admin');
 const serviceAccount = path.join(__dirname, '../..', 'keys', 'fb-key.json');
@@ -99,7 +98,10 @@ app.get('/highscores', async (req, res) => {
   if (querySnapshot.empty) {
     res.status(204).send('No highscores found');
   } else {
-    const users = querySnapshot.docs.map((doc: any) => doc.data() as User);
+    const users = querySnapshot.docs.map((doc: any) => ({
+      id: doc.id,
+      ...doc.data(),
+    }));
     res.status(200).send(users);
   }
 });

frontend/android/AndroidManifest.xml

@@ -4,6 +4,7 @@
     package="com.game.tankwars">
 
     <uses-feature android:glEsVersion="0x00020000" android:required="true" />
+    <uses-permission android:name="android.permission.INTERNET" />
 
     <application
         android:allowBackup="true"
@@ -12,7 +13,8 @@
         android:isGame="true"
         android:appCategory="game"
         android:label="@string/app_name"
-        tools:ignore="UnusedAttribute">
+        tools:ignore="UnusedAttribute"
+        android:usesCleartextTraffic="true">
         <activity
             android:name="com.game.tankwars.AndroidLauncher"
             android:label="@string/app_name" 

frontend/core/src/com/game/tankwars/Callback.java

+package com.game.tankwars;
+
+public interface Callback {
+    // This interface defines two methods to handle the different responses from an HTTP request
+
+    // Method to handle a successful response
+    // Takes a String parameter containing the response body
+    void onResult(String result);
+
+    // Method to handle a failed response
+    // Takes a Throwable parameter containing the exception that caused the failure
+    void onFailed(Throwable t);
+}
\ No newline at end of file

frontend/core/src/com/game/tankwars/ReceiverHandler.java

+package com.game.tankwars;
+
+import com.badlogic.gdx.Net;
+import com.badlogic.gdx.Net.HttpResponse;
+import com.game.tankwars.controller.LeaderboardController;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.util.ArrayList;
+import java.util.List;
+
+public class ReceiverHandler implements Net.HttpResponseListener {
+    // This class handles the response from the HTTP request
+    // It uses the callback interface to handle the different responses
+
+    // Declare a Callback instance to handle the different responses
+    private final Callback callback;
+
+    // Constructor to initialize the Callback instance
+    public ReceiverHandler(Callback callback) {
+        this.callback = callback;
+    }
+
+    // Method called if the request was cancelled
+    public void cancelled() {
+        System.out.println("cancelled");
+    }
+
+    // Method called if the request failed
+    public void failed(Throwable t) {
+        // Call the onFailed() method of the Callback instance
+        callback.onFailed(t);
+        // Print the error to the console
+        System.err.println(t);
+    }
+
+    // Method called if the request was successful and a response was received
+    public void handleHttpResponse(HttpResponse httpResponse) {
+        // Call the onResult() method of the Callback instance
+        // Pass in the response body as a String
+        callback.onResult(httpResponse.getResultAsString());
+    }
+}
\ No newline at end of file

frontend/core/src/com/game/tankwars/controller/LeaderboardController.java

+package com.game.tankwars.controller;
+
+import com.badlogic.gdx.Gdx;
+import com.badlogic.gdx.Net;
+import com.badlogic.gdx.net.HttpRequestBuilder;
+import com.badlogic.gdx.utils.Array;
+import com.badlogic.gdx.utils.Json;
+import com.game.tankwars.Callback;
+import com.game.tankwars.ReceiverHandler;
+import com.game.tankwars.model.User;
+
+public class LeaderboardController {
+    Array<User> leaderboardUsers;
+    private int retries = 0;
+
+    public void fetchLeaderboard() {
+        // Create a new instance of the Callback interface to handle the response
+        Callback callback = new Callback() {
+            // Method called if the response is successful
+            @Override
+            public void onResult(String leaderboard) {
+                // Create a new Json instance to parse the response body
+                Json json = new Json();
+                // Convert the response body to an Array of User objects using the Json instance
+                leaderboardUsers = json.fromJson(Array.class, User.class, leaderboard);
+            }
+            // Method called if the response fails
+            @Override
+            public void onFailed(Throwable t){
+                // Increment the number of retries
+                retries += 1;
+            }
+        };
+        // Define the URL for the HTTP request
+        String url = "http://localhost:3000/highscores";
+        // Create a new HttpRequest using the HttpRequestBuilder class
+        Net.HttpRequest httpRequest = new HttpRequestBuilder()
+                .newRequest()
+                .method(Net.HttpMethods.GET)
+                .url(url)
+                .build();
+        // Send the HttpRequest and pass in the Callback instance to handle the response
+        Gdx.net.sendHttpRequest(httpRequest, new ReceiverHandler(callback));
+    }
+
+    public Array<User> getLeaderboard() {
+        if (retries < 5 && leaderboardUsers == null) {
+            fetchLeaderboard();
+        }
+        return leaderboardUsers;
+    }
+}

frontend/core/src/com/game/tankwars/controller/MainMenuController.java

@@ -7,6 +7,7 @@ import com.badlogic.gdx.utils.Array;
 import com.game.tankwars.TankWarsGame;
 import com.game.tankwars.model.MenuButton;
 import com.game.tankwars.view.GameScreen;
+import com.game.tankwars.view.LeaderboardScreen;
 
 public class MainMenuController {
 
@@ -41,11 +42,8 @@ public class MainMenuController {
                 touchPos.y >= menuButton.getY() && touchPos.y <= menuButton.getY() + menuButton.getHeight()) {
 
                 switch (i) {
-                    case 0:
-                        // TODO: Clear resource manager
-                        tankWarsGame.setScreen(new GameScreen(tankWarsGame));
-                        break;
-                    case 1: System.out.println("Leaderboard button: Not yet functional"); break;
+                    case 0: tankWarsGame.setScreen(new GameScreen(tankWarsGame)); break;
+                    case 1: tankWarsGame.setScreen(new LeaderboardScreen(tankWarsGame)); break;
                     case 2: System.out.println("Settings button: Not yet functional"); break;
                     case 3: System.out.println("Log out button: Not yet functional"); break;
                 }

frontend/core/src/com/game/tankwars/model/User.java

+package com.game.tankwars.model;
+
+public class User {
+    int games;
+    float highscore;
+    int losses;
+    public int wins;
+    public String username;
+    public String id;
+
+    public User(int games, float highscore, int losses, int wins, String username, String id) {
+        this.games = games;
+        this.highscore = highscore;
+        this.losses = losses;
+        this.wins = wins;
+        this.username = username;
+        this.id = id;
+    }
+
+    public User() {
+        // Initialize default values for the fields
+        games = 0;
+        highscore = 0.0f;
+        losses = 0;
+        wins = 0;
+        username = null;
+        id = null;
+    }
+
+    @Override
+    public String toString() {
+        return "User {" +
+                "games=" + games +
+                ", highscore=" + highscore +
+                ", losses=" + losses +
+                ", wins=" + wins +
+                ", username='" + username + '\'' +
+                ", id='" + id + '\'' +
+                '}';
+    }
+}

frontend/core/src/com/game/tankwars/view/LeaderboardScreen.java

+package com.game.tankwars.view;
+
+import com.badlogic.gdx.Gdx;
+import com.badlogic.gdx.Screen;
+import com.badlogic.gdx.graphics.Color;
+import com.badlogic.gdx.graphics.OrthographicCamera;
+import com.badlogic.gdx.graphics.g2d.BitmapFont;
+import com.badlogic.gdx.graphics.g2d.SpriteBatch;
+import com.badlogic.gdx.scenes.scene2d.ui.Table;
+import com.badlogic.gdx.utils.Array;
+import com.badlogic.gdx.utils.ScreenUtils;
+import com.game.tankwars.TankWarsGame;
+import com.game.tankwars.controller.LeaderboardController;
+import com.game.tankwars.model.User;
+
+import java.awt.Label;
+
+public class LeaderboardScreen implements Screen {
+
+    final TankWarsGame tankWarsGame;
+    OrthographicCamera camera;
+    SpriteBatch batch;
+    private BitmapFont font;
+
+    //LibGDX have tables or something, should be investigated
+    Table table;
+
+    private Array<User> leaderboardUsers;
+    LeaderboardController leaderboardController;
+
+
+
+    public LeaderboardScreen (final TankWarsGame tankWarsGame) {
+        this.tankWarsGame = tankWarsGame;
+        camera = new OrthographicCamera();
+        batch = new SpriteBatch();
+        font = new BitmapFont();
+        font.getData().setScale(3f);
+        font.setColor(Color.BLACK);
+
+        leaderboardController = new LeaderboardController();
+    }
+
+    @Override
+    public void render(float delta) {
+        ScreenUtils.clear(255, 255, 255, 1);
+        int height = Gdx.graphics.getHeight() - 75;
+        batch.begin();
+        leaderboardUsers = leaderboardController.getLeaderboard();
+
+        if (leaderboardUsers == null) {
+            font.draw(batch, "No connection", 50, height);
+        }
+        else if (leaderboardUsers.size > 0) {
+            for (User user : leaderboardUsers) {
+                font.draw(batch, user.username, (Gdx.graphics.getWidth() >> 1) - 300, height);
+                font.draw(batch, user.wins + "", (Gdx.graphics.getWidth() >> 1), height);
+                height = height - 75;
+            }
+        }
+        else {
+            font.draw(batch, "No users", 50, height);
+        }
+        batch.end();
+    }
+
+    @Override
+    public void dispose() {
+
+    }
+
+    @Override
+    public void show() {
+
+    }
+    @Override
+    public void resize(int width, int height) {
+
+    }
+
+    @Override
+    public void pause() {
+
+    }
+
+    @Override
+    public void resume() {
+
+    }
+
+    @Override
+    public void hide() {
+
+    }
+
+}

frontend/core/src/com/game/tankwars/view/MainMenuScreen.java

@@ -25,7 +25,6 @@ public class MainMenuScreen extends InputAdapter implements Screen {
     private final BitmapFont font;
     private final Viewport viewport;
     private final MainMenuController controller;
-
     private final Sprite logo;
     private final Texture welcomeBox;
     private final Texture background;