Removed SnakeYAML to prevent crashes on older devices (#302)

build.gradle

@@ -29,7 +29,6 @@ dependencies {
 	implementation 'androidx.preference:preference:1.2.0'
 	implementation 'androidx.room:room-runtime:2.5.1'
 	annotationProcessor 'androidx.room:room-compiler:2.5.1'
-	implementation 'org.yaml:snakeyaml:2.0'
 }
 
 repositories {

proguard-project.txt

@@ -24,11 +24,3 @@
 -keepclassmembers class io.github.sspanak.tt9.languages.LanguageDefinition {
    public *;
 }
-
-# SnakeYAML shall not complain. As resolved by Mozilla:
-# https://github.com/mozilla-mobile/focus-android/blob/main/app/proguard-rules.pro
--dontwarn java.beans.BeanInfo
--dontwarn java.beans.FeatureDescriptor
--dontwarn java.beans.IntrospectionException
--dontwarn java.beans.Introspector
--dontwarn java.beans.PropertyDescriptor

src/io/github/sspanak/tt9/languages/Language.java

@@ -61,7 +61,7 @@ public class Language {
 		lang.locale = definitionLocale;
 		lang.name = definition.name.isEmpty() ? lang.name : definition.name;
 
-		for (int key = 0; key <= 9 || key < definition.layout.size(); key++) {
+		for (int key = 0; key <= 9 && key < definition.layout.size(); key++) {
 			lang.layout.add(keyCharsFromDefinition(key, definition.layout.get(key)));
 		}
 

src/io/github/sspanak/tt9/languages/LanguageDefinition.java

@@ -2,13 +2,15 @@ package io.github.sspanak.tt9.languages;
 
 import android.content.res.AssetManager;
 
-import org.yaml.snakeyaml.Yaml;
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
 
 import java.io.BufferedReader;
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
+import java.util.Arrays;
 
 import io.github.sspanak.tt9.Logger;
 
@@ -23,12 +25,19 @@ public class LanguageDefinition {
 	public String locale = "";
 	public String name = "";
 
+
+	/**
+	 * getAllFiles
+	 * Returns a list of the paths of all language definition files in the assets folder or an empty list on error.
+	 */
 	public static ArrayList<String> getAllFiles(AssetManager assets) {
 		ArrayList<String> files = new ArrayList<>();
 		try {
 			for (String file : assets.list(definitionsDir)) {
 				files.add(definitionsDir + "/" + file);
 			}
+
+			Logger.d("LanguageDefinition", "Found: " + files.size() + " languages.");
 		} catch (IOException e) {
 			Logger.e("tt9.LanguageDefinition", "Failed reading language definitions from: '" + definitionsDir + "'. " + e.getMessage());
 		}
@@ -36,11 +45,144 @@ public class LanguageDefinition {
 		return files;
 	}
 
-	public static LanguageDefinition fromFile(AssetManager assets, String definitionFile) throws IOException {
-		BufferedReader reader = new BufferedReader(new InputStreamReader(assets.open(definitionFile), StandardCharsets.UTF_8));
-		return new Yaml().loadAs(reader, LanguageDefinition.class);
+
+	/**
+	 * fromFile
+	 * Takes the path to a language definition in the assets folder and parses that file into a LanguageDefinition
+	 * or throws an IOException on error.
+	 */
+	public static LanguageDefinition fromFile(AssetManager assetManager, String definitionFile) throws IOException {
+		return parse(load(assetManager, definitionFile));
 	}
 
+
+	/**
+	 * load
+	 * Loads a language definition file from the assets folder into a String or throws an IOException on error.
+	 */
+	private static ArrayList<String> load(AssetManager assetManager, String definitionFile) throws IOException {
+		BufferedReader reader = new BufferedReader(new InputStreamReader(assetManager.open(definitionFile), StandardCharsets.UTF_8));
+		ArrayList<String> fileContents = new ArrayList<>();
+		String line;
+		while ((line = reader.readLine()) != null) {
+			fileContents.add(line);
+		}
+
+		return fileContents;
+	}
+
+
+	/**
+	 * parse
+	 * Converts "yaml" to a LanguageDefinition object. All properties in the YAML are considered optional,
+	 * so the LanguageDefinition defaults will be used when some property is omitted.
+	 *
+	 * Had to write all this, because the only usable library, SnakeYAML, works fine on Android 10+,
+	 * but causes crashes on older devices.
+	 */
+	@NonNull
+	private static LanguageDefinition parse(ArrayList<String> yaml) {
+		LanguageDefinition definition = new LanguageDefinition();
+		String value;
+
+		value = getPropertyFromYaml(yaml, "absString");
+		definition.abcString = value != null ? value : definition.abcString;
+
+		value = getPropertyFromYaml(yaml, "dictionaryFile");
+		definition.dictionaryFile = value != null ? value : definition.dictionaryFile;
+
+		value = getPropertyFromYaml(yaml, "locale");
+		definition.locale = value != null ? value : definition.locale;
+
+		value = getPropertyFromYaml(yaml, "name");
+		definition.name = value != null ? value : definition.name;
+
+		definition.layout = getLayoutFromYaml(yaml);
+
+		value = getPropertyFromYaml(yaml, "hasUpperCase");
+		if (value != null) {
+			value = value.toLowerCase();
+			definition.hasUpperCase = value.equals("true") || value.equals("on") || value.equals("yes") || value.equals("y");
+		}
+
+		return definition;
+	}
+
+
+	/**
+	 * getPropertyFromYaml
+	 * Finds "property" in the "yaml" and returns its value.
+	 * Optional properties are allowed. NULL will be returned when they are missing.
+	 */
+	@Nullable
+	private static String getPropertyFromYaml(ArrayList<String> yaml, String property) {
+		for (String line : yaml) {
+			line = line.replaceAll("#.+$", "").trim();
+			String[] parts = line.split(":");
+			if (parts.length < 2) {
+				continue;
+			}
+
+			if (property.equals(parts[0].trim())) {
+				return parts[1].trim();
+			}
+		}
+
+		return null;
+	}
+
+
+	/**
+	 * getLayoutFromYaml
+	 * Finds and extracts the keypad layout. Less than 10 keys are accepted allowed leaving the ones up to 9-key empty.
+	 */
+	@NonNull
+	private static ArrayList<ArrayList<String>> getLayoutFromYaml(ArrayList<String> yaml) {
+		ArrayList<ArrayList<String>> layout = new ArrayList<>();
+
+		boolean inLayout = false;
+		for (int i = 0; i < yaml.size(); i++) {
+			if (yaml.get(i).contains("layout")) {
+				inLayout = true;
+				continue;
+			}
+
+			if (inLayout) {
+				ArrayList<String> lineChars = getLayoutEntryFromYamlLine(yaml.get(i));
+				if (lineChars != null) {
+					layout.add(lineChars);
+				} else {
+					break;
+				}
+			}
+		}
+
+		return layout;
+	}
+
+
+	/**
+	 * getLayoutEntryFromYamlLine
+	 * Validates a YAML line as an array and returns the character list to be assigned to a given key (a layout entry).
+	 * If the YAML line is invalid, NULL will be returned.
+	 */
+	@Nullable
+	private static ArrayList<String> getLayoutEntryFromYamlLine(String yamlLine) {
+		if (!yamlLine.contains("[") || !yamlLine.contains("]")) {
+			return null;
+		}
+
+		String line = yamlLine
+			.replaceAll("#.+$", "")
+			.replace('-', ' ')
+			.replace('[', ' ')
+			.replace(']', ' ')
+			.replace(" ", "");
+
+		return new ArrayList<>(Arrays.asList(line.split(",")));
+	}
+
+
 	public String getDictionaryFile() {
 		return languagesDir + "/dictionaries/" + dictionaryFile;
 	}