Added main logic for trivia file support

Added main logic for trivia file support and renamed exception class `InvalidTriviaFormatException`.

app/src/main/java/com/luca0n/joguitos/pluck/activities/MainActivity.java

@@ -23,9 +23,12 @@ Contact us at <joguitos+pluck@luca0n.com>.
 
 package com.luca0n.joguitos.pluck.activities;
 
+import android.app.Activity;
 import android.content.Intent;
+import android.content.SharedPreferences;
 import android.os.Build;
 import android.os.Bundle;
+import android.preference.PreferenceManager;
 import android.widget.ArrayAdapter;
 import android.widget.Button;
 import android.widget.Spinner;
@@ -33,6 +36,7 @@ import androidx.appcompat.app.AlertDialog;
 
 import butterknife.BindView;
 import butterknife.ButterKnife;
+
 import com.luca0n.joguitos.pluck.R;
 import com.luca0n.joguitos.pluck.trivia.TriviaSource;
 import com.luca0n.joguitos.pluck.trivia.TriviaCategory;
@@ -52,6 +56,8 @@ public class MainActivity extends BaseActivity {
 	@BindView(R.id.spinner_difficulty)
 	Spinner spinnerDifficulty;
 
+	private static final int REQUEST_OPEN_DOCUMENT = 0;
+
 	@Override
 	protected void onCreate(Bundle savedInstanceState) {
 		super.onCreate(savedInstanceState);
@@ -64,6 +70,9 @@ public class MainActivity extends BaseActivity {
 				// Check the Android version.
 				if (Build.VERSION.SDK_INT >= 19){
 					// TODO: Show the open document dialog and read the trivia file.
+					Intent i = new Intent(Intent.ACTION_OPEN_DOCUMENT);
+					i.setType("*/*");
+					startActivityForResult(i, REQUEST_OPEN_DOCUMENT);
 					return;
 				} else {
 					// Unsupported version.
@@ -80,12 +89,28 @@ public class MainActivity extends BaseActivity {
 			TriviaCategory category = (TriviaCategory) spinnerCategory.getSelectedItem();
 			TriviaDifficulty difficulty = (TriviaDifficulty) spinnerDifficulty.getSelectedItem();
 
+			// Put the server address in the TriviaQuery object.	
+			SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
+			String serverKey = getResources().getString(R.string.pref_network_server);
+			// Load default server URL in case the player did not specify a custom server URL.
+			String defaultServer = getResources().getString(R.string.pref_network_server_default);
+			String base = sp.getString(serverKey, defaultServer) + "?"; // append "?" to the end of the URL so we can specify GET parameters.
+
+			// Check if the custom server URL preference was empty. If it was, change it to the default URL.
+			if (base.equals("?")){
+				base = defaultServer + "?";
+				sp.edit().putString(serverKey, defaultServer).commit();
+			}
+
 			TriviaQuery query = new TriviaQuery.Builder(amount)
 				.category(category)
 				.difficulty(difficulty)
+				.base(base)
 				.build();
 
+			// Launch the trivia game activity.
 			Intent intent = new Intent(getApplicationContext(), TriviaGameActivity.class);
+			intent.putExtra(TriviaGameActivity.EXTRA_TRIVIA_SOURCE, TriviaSource.SERVER.getName()); // Specify the trivia source.
 			intent.putExtra(TriviaGameActivity.EXTRA_TRIVIA_QUERY, query);
 			startActivity(intent);
 		});
@@ -112,4 +137,33 @@ public class MainActivity extends BaseActivity {
 				new ArrayAdapter<>(
 					this, android.R.layout.simple_list_item_1, TriviaDifficulty.values()));
 	}
+
+	@Override
+	public void onActivityResult(int requestCode, int resultCode, Intent extras){
+		switch (requestCode){
+			case REQUEST_OPEN_DOCUMENT:
+				// Was the request executed successfully?
+				if (resultCode == Activity.RESULT_OK){
+					// Check if the user canceled the operation.
+					if (extras == null)
+						break;
+
+					Intent intent = new Intent(getApplicationContext(), TriviaGameActivity.class);
+					intent.putExtra(TriviaGameActivity.EXTRA_TRIVIA_SOURCE, TriviaSource.FILE.getName()); // Specify the trivia source.
+					intent.putExtra(TriviaGameActivity.EXTRA_TRIVIA_SOURCE_DATA, extras.getData()); // Specify the trivia source data. In this case, since the user chose the "File" source option, we should put the file Uri object here.
+					startActivity(intent);
+				} else {
+					new AlertDialog.Builder(this)
+						.setIcon(android.R.drawable.ic_dialog_alert)
+						.setTitle(R.string.error)
+						.setMessage(R.string.error_trivia_file_fetch_unknown)
+						.setPositiveButton(android.R.string.ok, null)
+						.show();
+				}
+				break;
+			default:
+				super.onActivityResult(requestCode, resultCode, extras);
+				break;
+		}
+	}
 }

app/src/main/java/com/luca0n/joguitos/pluck/activities/TriviaGameActivity.java

@@ -23,7 +23,6 @@ Contact us at <joguitos+pluck@luca0n.com>.
 
 package com.luca0n.joguitos.pluck.activities;
 
-import android.app.AlertDialog;
 import android.content.Intent;
 import android.content.res.ColorStateList;
 import android.graphics.PorterDuff;
@@ -32,6 +31,7 @@ import android.os.AsyncTask;
 import android.os.Build;
 import android.os.Bundle;
 import android.os.Handler;
+import android.net.Uri;
 import android.view.View;
 import android.view.MenuItem;
 import android.widget.Button;
@@ -40,30 +40,40 @@ import android.widget.ProgressBar;
 import android.widget.TextView;
 
 import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.io.Reader;
+import java.io.InputStreamReader;
+import java.io.InputStream;
+import java.io.BufferedReader;
 
 import androidx.appcompat.app.ActionBar;
+import androidx.appcompat.app.AlertDialog;
 import androidx.fragment.app.Fragment;
 import androidx.fragment.app.FragmentTransaction;
 import butterknife.BindView;
 import butterknife.ButterKnife;
 import com.luca0n.joguitos.pluck.R;
 import com.luca0n.joguitos.pluck.exceptions.NoTriviaResultsException;
-import com.luca0n.joguitos.pluck.exceptions.InvalidServerResponseException;
+import com.luca0n.joguitos.pluck.exceptions.InvalidTriviaFormatException;
 import com.luca0n.joguitos.pluck.fragments.TriviaGameErrorFragment;
 import com.luca0n.joguitos.pluck.fragments.TriviaQuestionFragment;
 import com.luca0n.joguitos.pluck.interfaces.IDownloadTriviaQuestionReceiver;
 import com.luca0n.joguitos.pluck.trivia.TriviaGame;
 import com.luca0n.joguitos.pluck.trivia.TriviaQuery;
 import com.luca0n.joguitos.pluck.trivia.TriviaQuestion;
+import com.luca0n.joguitos.pluck.trivia.TriviaSource;
 import com.luca0n.joguitos.pluck.util.ApiUtil;
 import com.luca0n.joguitos.pluck.util.SoundUtil;
 
 public class TriviaGameActivity extends BaseActivity
 	implements IDownloadTriviaQuestionReceiver {
 	static final String EXTRA_TRIVIA_QUERY = "extra_trivia_query";
+	static final String EXTRA_TRIVIA_SOURCE = "extra_trivia_source";
+	static final String EXTRA_TRIVIA_SOURCE_DATA = "extra_trivia_source_data";
 	private final String STATE_TRIVIA_GAME = "state_trivia_game";
 
 	private TriviaGame game;
+	private TriviaSource source;
 
 	@BindView(R.id.progress_bar)
 	ProgressBar progressBar;
@@ -96,22 +106,34 @@ public class TriviaGameActivity extends BaseActivity
 			progressBar.setVisibility(View.VISIBLE);
 
 			// Gather information about the trivia location.
-			/*String triviaLocation;
+			String sourceData;
-
+			source = TriviaSource.get(bundle.getString(EXTRA_TRIVIA_SOURCE));
-			switch (triviaLocation){
+			switch (source){
-				case "GET_FROM_URL":*/
+				case SERVER:
 					DownloadTriviaQuestionsTask task = new DownloadTriviaQuestionsTask();
 					task.setReceiver(this);
-					task.execute(query);/*
+					task.execute(query);
 					break;
-				case "GET_FROM_FILE":
+				case FILE:
-
+					// Attempt to open the trivia file specified by the player.
+					// Read the file as a plain text JSON trivia file.
+					StringBuilder sb = new StringBuilder();
+					try {
+						InputStream is = getContentResolver().openInputStream((Uri) bundle.get(EXTRA_TRIVIA_SOURCE_DATA));
+						Reader in = new BufferedReader(new InputStreamReader(is, StandardCharsets.UTF_8));
+						for (int c; (c = in.read()) >= 0;)
+							sb.append((char) c);
+					} catch (IOException e){
+						onException(e);
+						return;
+					}
+					onTriviaQuestionsDownloaded(sb.toString());
 					break;
 				default:
-					// Unknown specified trivia location.
+					// Unknown trivia source.
 					// TODO: Show error message to the user about this internal error.
 					break;
-			}*/
+			}
 		}
 	}
 
@@ -159,6 +181,8 @@ public class TriviaGameActivity extends BaseActivity
 				this.game = new TriviaGame(ApiUtil.jsonToQuestionArray(json));
 			} catch (Exception e) {
 				//onNoTriviaResults();
+				new AlertDialog.Builder(this)
+					.setMessage(e.toString()).show();
 				onException(e);
 				return;
 			}
@@ -214,12 +238,19 @@ public class TriviaGameActivity extends BaseActivity
 		// Hide the progress bar.
 		progressBar.setVisibility(View.GONE);
 		String msg;
+		int id;
 		if (e instanceof NoTriviaResultsException)
-			msg = getResources().getString(R.string.error_no_trivia_results);
+			id = R.string.error_no_trivia_results;
-		else if (e instanceof InvalidServerResponseException)
+		else if (e instanceof InvalidTriviaFormatException)
-			msg = getResources().getString(R.string.error_server_response_invalid);
+			// Check the trivia source type.
+			if (source == TriviaSource.SERVER)
+				id = R.string.error_server_response_invalid;
+			else
+				id = R.string.error_trivia_file_invalid;
 		else 
-			msg = getResources().getString(R.string.error_unknown);
+			id = R.string.error_unknown;
+
+		msg = getResources().getString(id);
 
 		Fragment errorFragment = TriviaGameErrorFragment.newInstance(msg);
 

app/src/main/java/com/luca0n/joguitos/pluck/exceptions/InvalidTriviaFormatException.java

@@ -0,0 +1,35 @@
+/*
+Pluck: an open source trivia game for Android
+
+Copyright (C) 2021 Joguitos do luca0N!
+
+This program is free software: you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free Software
+Foundation, either version 3 of the License, or (at your option) any later
+version.
+
+This program is distributed in the hope that it will be useful, but WITHOUT
+ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License along with
+this program. If not, see <https://www.gnu.org/licenses/>.
+
+This game is a fork of LibreTrivia, and its source code is available at
+<https://github.com/tryton-vanmeer/LibreTrivia>.
+
+Contact us at <joguitos+pluck@luca0n.com>.
+*/
+
+package com.luca0n.joguitos.pluck.exceptions;
+
+import java.lang.Throwable;
+
+public class InvalidTriviaFormatException extends Exception {
+	public InvalidTriviaFormatException(){
+		super();
+	}
+	public InvalidTriviaFormatException(Throwable cause){
+		super(cause);
+	}
+}

app/src/main/java/com/luca0n/joguitos/pluck/trivia/TriviaQuery.java

@@ -23,15 +23,8 @@ Contact us at <joguitos+pluck@luca0n.com>.
 
 package com.luca0n.joguitos.pluck.trivia;
 
-import com.luca0n.joguitos.pluck.PluckApplication;
-import com.luca0n.joguitos.pluck.R;
-
 import java.io.Serializable;
 
-import android.content.Context;
-import android.content.SharedPreferences;
-import android.preference.PreferenceManager;
-
 public class TriviaQuery implements Serializable {
 	private static final int DEFAULT_AMOUNT = 10;
 
@@ -39,11 +32,13 @@ public class TriviaQuery implements Serializable {
 	private final TriviaCategory category;
 	private final TriviaDifficulty difficulty;
 	private final TriviaType type;
+	private final String base;
 
 	private TriviaQuery(Builder builder) {
 		this.amount = builder.amount;
 		this.category = builder.category;
 		this.difficulty = builder.difficulty;
+		this.base = builder.base;
 		this.type = builder.type;
 	}
 
@@ -52,6 +47,7 @@ public class TriviaQuery implements Serializable {
 		private TriviaCategory category;
 		private TriviaDifficulty difficulty;
 		private TriviaType type;
+		private String base;
 
 		public Builder() {
 			this.amount = DEFAULT_AMOUNT;
@@ -80,6 +76,11 @@ public class TriviaQuery implements Serializable {
 			return this;
 		}
 
+		public Builder base(String base){
+			this.base = base;
+			return this;
+		}
+
 		public TriviaQuery build() {
 			return new TriviaQuery(this);
 		}
@@ -89,20 +90,6 @@ public class TriviaQuery implements Serializable {
 	public String toString() {
 		StringBuilder url = new StringBuilder();
 
-		// Load custom server URL.
-		Context c = PluckApplication.getAppContext();
-		SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(c);
-		String serverKey = c.getResources().getString(R.string.pref_network_server);
-		// Load default server URL in case the player did not specify a custom server URL.
-		String defaultServer = c.getResources().getString(R.string.pref_network_server_default);
-		String base = sp.getString(serverKey, defaultServer) + "?"; // append "?" to the end of the URL so we can specify GET parameters.
-
-		// Check if the custom server URL preference was empty. If it was, change it to the default URL.
-		if (base.equals("?")){
-			base = defaultServer + "?";
-			sp.edit().putString(serverKey, defaultServer).commit();
-		}
-
 		url.append(base);
 		url.append("amount=").append(this.amount);
 

app/src/main/java/com/luca0n/joguitos/pluck/util/ApiUtil.java

@@ -47,7 +47,7 @@ import java.util.ArrayList;
 import com.luca0n.joguitos.pluck.R;
 import com.luca0n.joguitos.pluck.PluckApplication;
 import com.luca0n.joguitos.pluck.exceptions.NoTriviaResultsException;
-import com.luca0n.joguitos.pluck.exceptions.InvalidServerResponseException;
+import com.luca0n.joguitos.pluck.exceptions.InvalidTriviaFormatException;
 import com.luca0n.joguitos.pluck.trivia.TriviaQuery;
 import com.luca0n.joguitos.pluck.trivia.TriviaQuestion;
 import com.luca0n.joguitos.pluck.trivia.TriviaQuestionBoolean;
@@ -105,13 +105,13 @@ public class ApiUtil {
 	}
 
 	public static ArrayList<TriviaQuestion> jsonToQuestionArray(String json)
-			throws NoTriviaResultsException, InvalidServerResponseException {
+			throws NoTriviaResultsException, InvalidTriviaFormatException {
 		JsonObject jsonObject;
 		try{
 			jsonObject = new JsonParser().parse(json).getAsJsonObject();
 		} catch (JsonSyntaxException e){
 			// Unknown server response.
-			throw new InvalidServerResponseException();
+			throw new InvalidTriviaFormatException(e);
 		}
 
 		if (jsonObject.get("response_code").getAsInt() == 1) {

app/src/main/res/layout/activity_main.xml

@@ -44,6 +44,16 @@ Contact us at <joguitos+pluck@luca0n.com>.
 			app:layout_constraintBottom_toBottomOf="parent"
 			app:layout_constraintTop_toTopOf="parent">
 
+			<!-- Trivia Source -->
+			<TextView
+				style="@style/TextLabel"
+				android:labelFor="@id/spinner_source"
+				android:text="@string/ui_source" />
+
+			<Spinner
+				android:id="@+id/spinner_source"
+				style="@style/Spinner" />
+
 			<!-- Select Amount -->
 			<TextView
 				style="@style/TextLabel"

app/src/main/res/values/strings.xml

@@ -95,6 +95,8 @@ Contact us at <joguitos+pluck@luca0n.com>.
 		<string name="error_server_response_invalid"><b>Server response error!</b>\n\nCould not parse the server response. The server response may be in a unsupported version. If you are using a custom server, make sure the server address points to a valid address and then try again.</string>
 		<string name="error_unknown"><b>An unknown error occurred!</b></string>
 		<string name="error_source_file_android_version_unsupported">Trivia files are not supported in this version of Android.</string>
+		<string name="error_trivia_file_invalid"><b>Invalid trivia file!</b>\n\nTrivia files should be in a plain text JSON format.</string>
+		<string name="error_trivia_file_fetch_unknown">An unknown error occurred while attempting to read the opened file.</string>
 
     <string name="title_activity_settings">Settings</string>